Mycobacterium smegmatis, which creates genome mosaicism in resulting strains and depends on an ESX-1 type VII secretion system. In contrast, only few data on interstrain DNA transfer are available for tuberculosis-causing mycobacteria, for which chromosomal DNA transfer between two Mycobacterium canettii strains was reported, a process which, however, was not observed for Mycobacterium tuberculosis strains. Here, we have studied a wide range of human- and animal-adapted members of the Mycobacterium tuberculosis complex (MTBC) using an optimized filter-based mating assay together with three selected strains of M. canettii that acted as DNA recipients. Unlike in previous approaches, we obtained a high yield of thousands of recombinants containing transferred chromosomal DNA fragments from various MTBC donor strains, as confirmed by whole-genome sequence analysis of 38 randomly selected clones. While the genome organizations of the obtained recombinants showed mosaicisms of donor DNA fragments randomly integrated into a recipient genome backbone, reminiscent of those described as being the result of ESX-1-mediated DCT in M. smegmatis, we observed similar transfer efficiencies when ESX-1-deficient donor and/or recipient mutants were used, arguing that in tubercle bacilli, HGT is an ESX-1-independent process. These findings provide new insights into the genetic events driving the pathoevolution of M. tuberculosis and radically change our perception of HGT in mycobacteria, particularly for those species that show recombinogenic population structures despite the natural absence of ESX-1 secretion systems.Current models of horizontal gene transfer (HGT) in mycobacteria are based on “distributive conjugal transfer” (DCT), an HGT type described in the fast-growing, saprophytic model organism  Mycobacterium smegmatis started to emerge decades ago  to a second strain (the recipient). This transfer probably originates from multiple transfer initiation sites, requiring recipient recombination functions as well as extended homology between the transferred donor DNA and the recipient chromosome  is a major factor in bacterial evolution, and it has shaped the genomes of many important pathogens , 2. In mades ago –5, and tdes ago –. From thromosome , 8. Thisromosome .M. smegmatis type VII (ESX) secretion systems in these processes was reported. Although only components of the transport machinery across the plasma membrane have been identified so far   segment in the 3′ region of the esx-1 locus, the replacement of which was linked to a switch from a recipient phenotype to a donor phenotype  , and a capsule, characterizing them functionally as diderm bacteria , 11. Howd so far –14, thes so far –, 16, witd ESX-4) . It was ficiency –20, leadiciency –, 22. Inthenotype . In tubein (BCG) , 24 and P Prague .Mycobacterium canettii, the only example to date of experimentally demonstrated chromosomal DNA transfer in slow-growing mycobacteria  evolved by clonal expansion into various lineages of human- and animal-adapted tubercle bacilli  and mutant strains of various tubercle bacilli, including representative MTBC members and M. canettii strain A (STB-A) (CIPT 140010059) to M. canettii strain L (STB-L) (CIPT 140070008)  with different degrees of relatedness to the MTBC   promptedescribed , and DsRanalysis . Interesanalysis . We obseanalysis , underlianalysis , 43. Whembinants . In folls donors . In contthe MTBC , were usesx-1 locus in M. smegmatis were reported to cause opposing effects on donor and recipient strains, whereby ESX-1 deficiency of the donor strain increased the transfer efficiency and ESX-1 deficiency in the recipient strain disabled transfer  of 1eccD, as expected, and a second one showing an additional, probably spontaneous, deletion of a 13.9-kb region starting 806 bp upstream of 1eccD, roughly coinciding with the RD1mic region deletion found in M. microti esx-1 locis H37Rv , an ESX-is H37Rv , and theF2122/97  as well F2122/97 , which aF2122/97 , 24.M. canettii donor mutants generated a higher DNA transfer efficiency than the corresponding WT strains  STB-L. Note the absence of reads for gene 1eccD (BN43_90410) in Δ1eccD strains as well as the lack of reads concerning an additional deletion affecting genes esxA and espI (BN43_90409). The absence of reads confirms the deletion of genes in the Δ1eccD recipient and recombinant that are essential for the function of the ESX-1 system. Download FIG S1, PDF file, 2.7 MB.Display of mapped Illumina sequencing reads generated from recipient strain STB-L ΔCopyright © 2021 Madacki et al.2021Madacki et al.https://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International license.This content is distributed under the terms of the de novo assembled from sequencing reads and compared against their corresponding donor and recipient genomes to distinguish donor-derived sequences from recipient sequences based on polymorphism signals detected between them. Bioinformatic analysis followed by visualization with the Artemis Comparison Tool (ACT)   revealedr genome . These sr genome , similarmegmatis . In one megmatis . This remegmatis .10.1128/mBio.00965-21.2FIG S21eccD was used as the recipient strain with the indicated donors. From the outer to the inner circle are (i) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and donor strains (orange), (ii) the donor strain reference genome (red), (iii) the best-scoring hits identified between the recombinant and donor strains (light red), (iv) the assembled recombinant genome , (v) the best-scoring hits identified between the recombinant and recipient strains (light blue), (vi) the recipient strain reference genome (blue), and (vii) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and recipient strains (purple). Black bars correspond to gap regions. Coordinates are indicated in megabases. Download FIG S2, PDF file, 2.0 MB.Circular representation of 21 selected genomes from recombinants (RCs) obtained when STB-L and/or STB-L ΔCopyright © 2021 Madacki et al.2021Madacki et al.https://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International license.This content is distributed under the terms of the 10.1128/mBio.00965-21.6TABLE S1Table S1, PDF file, 0.07 MB.List of recombinant strains that were subjected to WGS. Donor-derived sequences were identified based on polymorphism signals between the recombinant sequence and the recipient reference sequence. For each fragment, start and end positions on the recipient reference genome are given. M, regions of microcomplexity; DS, regions where additional donor-specific sequences are present inside the transferred fragment. For each of these fragments, start and end positions on the donor reference genome are also given. Download Copyright © 2021 Madacki et al.2021Madacki et al.https://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International license.This content is distributed under the terms of the plcABC and ppe38-ppe71 genes  or Pro-Pro-Glu (PPE) motifs, belonging to the PPE major polymorphic tandem repeat (PPE-MPTR) and PE polymorphic GC-rich-repetitive sequence (PE_PGRS) subfamilies, respectively, via the cognate ESX-5 type VII secretion system  to the STB-L recipient  the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and donor strains (orange), (ii) the donor strain reference genome (red), (iii) the best-scoring hits identified between the recombinant and donor strains (light red), (iv) the assembled recombinant genome , (v) the best-scoring hits identified between the recombinant and recipient strains (light blue), (vi) the recipient strain reference genome (blue), and (vii) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and recipient strains (purple). Black bars correspond to gap regions. Coordinates are indicated in megabases. RC, recombinant. Download Copyright © 2021 Madacki et al.2021Madacki et al.https://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International license.This content is distributed under the terms of the M. smegmatis , as well as recombinants STB-G/STB-K RC1 and STB-G/STB-E RC1, where the STB-G donor had received the pMRF1-dsRed plasmid and, in the case of STB-G/STB-E RC1, chromosomal DNA segments from the STB-E recipient (bottom right). From the outer to the inner circle are (i) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and donor strains (orange), (ii) the donor strain reference genome (red), (iii) the best-scoring hits identified between the recombinant and donor strains (light red), (iv) the assembled recombinant genome , (v) the best-scoring hits identified between the recombinant and recipient strains (light blue), (vi) the recipient strain reference genome (blue), and (vii) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and recipient strains (purple). Black bars correspond to gap regions. Coordinates are indicated in megabases. Each recombinant is denoted as the integrative vector-containing donor/DsRed-producing recipient. Download Copyright © 2021 Madacki et al.2021Madacki et al.https://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International license.This content is distributed under the terms of the Importantly, among donor strains that were able to provide recombinants with STB-G and STB-I recipients was strain STB-L, and an additional cross between the STB-G donor and the STB-L recipient also resulted in recombinants, suggesting that bidirectional transfer is possible between these two strains .10.1128/mBio.00965-21.5FIG S5FIG S5, PDF file, 1.0 MB.Circular representation of recombinants showing bidirectional transfer between the STB-G and STB-L strains. From the outer to the inner circle are (i) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and donor strains (orange), (ii) the donor strain reference genome (red), (iii) the best-scoring hits identified between the recombinant and donor strains (light red), (iv) the assembled recombinant genome , (v) the best-scoring hits identified between the recombinant and recipient strains (light blue), (vi) the recipient strain reference genome (blue), and (vii) the density of detected variants calculated in 5-kb nonoverlapping windows between the recombinant and recipient strains (purple). Black bars correspond to gap regions. Coordinates are indicated in megabases. RC, recombinant. Download Copyright © 2021 Madacki et al.2021Madacki et al.https://creativecommons.org/licenses/by/4.0/Creative Commons Attribution 4.0 International license.This content is distributed under the terms of the M. canettii clade depicting a recombinogenic population structure  out of six previously reported so-called mid (mating identity) genes (M. smegmatis isolates PM5/mc2874 and Jucho (Saccharomyces cerevisiae (A closer look shows that only three (y) genes  and thatrevisiae .M. smegmatis did not identify any transport proteins essential for this process, and rather paradoxically, a deletion in the type VII secretion system ESX-1 of the M. smegmatis donor was found to enhance transfer  catalyzed by Ku and DNA ligase D (LigD), the AdnAB helicase-nuclease, and single-strand annealing (SSA)  , 68. It plcABC and ppe38-ppe71 genes, which is characteristic of the M. bovis/M. bovis BCG  liquid medium or LB agar plates at 37°C. When required, the following antibiotics were added: kanamycin (25 μg/ml for mycobacteria other than M. kansasii and 50 μg/ml for E. coli and M. kansasii), hygromycin (50 μg/ml for mycobacteria and 200 μg/ml for E. coli), zeocin (25 μg/ml), and gentamicin (25 μg/ml).Mycobacterial strains  of 1.5. Five hundred microliters of donor and 500 μl of recipient cell suspensions were mixed, the mixture was passed through a 0.45-μm filter (Merck Millipore), and the filter was placed with the bacterial side up on a 7H11 agar plate without antibiotics, which was incubated for 7 days at 37°C. After incubation, bacteria were scraped off the filter and thoroughly resuspended in fresh liquid medium, and recombinants were selected on 7H11 plates containing kanamycin and hygromycin. For assays where the conjugation efficiency was to be determined, these bacterial suspensions were also plated on single-antibiotic-containing plates, and the efficiency was calculated as the number of recombinants per recovered donor or recipient cell. In order to exclude spontaneous resistance to hygromycin, recipient monocultures were also filtered and plated on double-antibiotic plates  and sacB as a counter-selective marker  AES, and recombinants were selected on plates containing kanamycin and zeocin at 37°C. Individual transformants were verified for 1eccD deletion by PCR, and once the correct deletion was confirmed, the pJV53 plasmid was cured by passaging on zeocin plates.In the case of STB-A, STB-D, and STB-K, each strain was first transformed with the plasmid pJV53 , and transformants were selected on kanamycin-containing plates at 37°C. The resulting strains were grown in 7H9 liquid medium supplemented with 0.2% succinate and 0.05% Tween 80 and induced at an ODsacB method, the linear AES was amplified using primers introducing end restriction sites for SpeI/XbaI  Each assembled recombinant genome was aligned against the reference genome of the corresponding donor and recipient strains  using NU+ v2.5.0+ ((ii) Each assembled recombinant genome was cut in 100-bp nonoverlapping windows and compared against the reference genome of the respective donor and recipient strains  using BL v2.5.0+   database under the study accession number


Multiparametric magnetic resonance imaging (MRI) is increasingly used to diagnose prostate cancer (PCa). It is not yet established whether all men with negative MRI (Prostate Imaging-Reporting and Data System version 2 score <3) should undergo prostate biopsy or not.To develop and validate a prediction model that uses clinical parameters to reduce unnecessary prostate biopsies by predicting PCa and clinically significant PCa (csPCa) for men with negative MRI findings who are at risk of harboring PCa.3, and/or suspicious digital rectal examination. The validation cohort included 182 men from another centre (University of Miami) with negative MRI who underwent systematic prostate biopsy with the same criteria.This was a retrospective analysis of 200 men with negative MRI at risk of PCa who underwent prostate biopsy (2014–2020) with prostate-specific antigen (PSA) >4 ng/ml, 4Kscore of >7%, PSA density ≥0.15 ng/ml/cmcsPCa was defined as Gleason grade group ≥2 on biopsy. Multivariable logistic regression analysis was performed using coefficients of logit function for predicting PCa and csPCa. Nomogram validation was performed by calculating the area under receiver operating characteristic curves (AUC) and comparing nomogram-predicted probabilities with actual rates of PCa and csPCa.Of 200 men in the development cohort, 18% showed PCa and 8% showed csPCa on biopsy. Of 182 men in the validation cohort, 21% showed PCa and 6% showed csPCa on biopsy. PSA density, 4Kscore, and family history of PCa were significant predictors for PCa and csPCa. The AUC was 0.80 and 0.87 for prediction of PCa and csPCa, respectively. There was agreement between predicted and actual rates of PCa in the validation cohort. Using the prediction model at threshold of 40, 47% of benign biopsies and 15% of indolent PCa cases diagnosed could be avoided, while missing 10% of csPCa cases. The small sample size and number of events are limitations of the study.Our prediction model can reduce the number of prostate biopsies among men with negative MRI without compromising the detection of csPCa.We developed a tool for selection of men with negative MRI (magnetic resonance imaging) findings for prostate cancer who should undergo prostate biopsy. This risk prediction tool safely reduces the number of men who need to undergo the procedure. Men with negative magnetic resonance imaging (MRI) findings pose a diagnostic challenge to physicians as they may have prostate cancer in the absence of accepted clinical predictors. Our model for selection of men with negative MRI findings for biopsy safely reduces the number of men who need to undergo a biopsy procedure. The introduction of mpMRI-targeted prostate biopsy has increased the detection of clinically significant disease and reduced the number of unnecessary biopsies and the detection of clinically indolent cancers 22.13, or suspicious digital rectal examination (DRE).This study was approved by the Institutional Review Board (GCO 19-1711) of the Icahn School of Medicine at Mount Sinai  within the Mount Sinai Health System. We retrospectively reviewed our institution’s prostate biopsy database to extract relevant patient records. Between January 2014 and December 2020, 2100 men underwent a 12-core systematic biopsy performed by a single expert surgeon (A.T.) with 20 yr of experience. The biopsies were performed with a spring-loaded biopsy gun and 18-gauge needles. An experienced genitourinary pathologist (K.H.) reviewed the biopsy samples. Indications for biopsy were one or more of the following: prostate-specific antigen (PSA) >4 ng/ml, a 4Kscore  of >7%, PSA density of ≥0.15 ng/ml/cm2.22.2.1All mpMRI scans were performed before the prostate biopsy procedure. A fasting period of 4 h was advised. Fleet enema was recommended before the examination.2.2.2Diagnostic mpMRI was conducted with the patient in the supine position.2.2.3Prostate evaluations were conducted using 3-T MRI systems equipped with a phased-array coil (development cohort) or a surface coil . The following sequences were obtained: multiplanar high-resolution T2 fast spin echo (FSE);, axial T1 FSE; axial diffusion-weighted imaging; axial T1 in and out of phase; and axial T1 perfusion before and after contrast injection (8 ml of Gadavist [gadobutrol] and 1 mg of glucagon via intramuscular injection). The mpMPI results were evaluated according to Prostate Imaging-Reporting and Data System version 2 (PI-RADS v2) 2.3n = 1740), mpMRI carried out after biopsy (n = 40), contraindication for 3-T mpMRI, inadequate image quality on mpMRI (n = 30), prior hormone therapy or radiation (n = 30), or missing information for clinical variables (n = 60). In total, 200 men were eligible for inclusion in the analysis. An external cohort of 182 men with negative MRI findings from the University of Miami  who underwent biopsy for PSA >4 ng/ml and had a 4Kscore of >7%, PSA density of ≥0.15 ng/ml/cm3, suspicious DRE, or a combination of these was used for validation.Patients were included in the study if they had negative MRI findings, defined as a PI-RADS v2 score of <3. Exclusion criteria were mpMRI results with a PI-RADS v2 score of ≥3  to evaluate the potential presence of substantial multicollinearity between these predictors in our model.For our model, the outcome for predicting PCa was defined as Gleason grade group ≥1 on biopsy. Men with this outcome were considered cases and men showing no cancer on biopsy were considered controls. The outcome for predicting csPCa was defined as Gleason grade group ≥2 on biopsy. Men with this outcome were considered cases and men who showed no cancer on biopsy or with Gleason grade group 1 were considered controls. Descriptive statistics for the two groups were collected. Results for continuous variables are reported as the median and interquartile range (IQR) and were compared using the Mann-Whitney Analysis of correlation coefficients between predictors, as well as the variance inflation index for the predictors, did not indicate the presence of strong collinearity between the 4Kscore and the other predictors in our model. There were no strong correlations (>0.8) between the 4Kscore and other predictors. Multivariable binary logistic regression analysis was performed for the presence of PCa and csPCa in the development cohort. The nomograms predicting PCa and csPCa were built using the coefficients of the logit function.p < 0.05.Nomogram validation was performed in the validation cohort in two stages. First, receiver operating characteristic curves were plotted for the presence of PCa and csPCa using the same variables used to build the nomogram. Second, calibration plots were generated by grouping cases into deciles according to their nomogram-predicted probability and then comparing the mean prediction for the group with the observed proportion of men with PCa or csPCa. Using nomogram-derived probability cutoffs, we calculated the number of biopsies that could be avoided without missing PCa or csPCa in the validation cohort. Statistical analyses were performed using STATA version 12  and SAS version 9.4 . All tests were two-tailed with a significance level of 33 (IQR 0.11–0.15) and 0.08 ng/ml/cm3 (IQR 0.06–0.09), and the median 4Kscore was 19 (IQR 13–28) and 9 (IQR 3–18) for men with PCa and men with benign biopsy, respectively. Of the 35 men with PCa, 19 (54%), 10 (28%), two (6%), two (6%), and two (6%) had Gleason grade group 1, 2, 3, 4, and 5, respectively. Of the 182 men in the validation cohort, 144 (79%) did not have PCa on biopsy. Of the remaining 38 men who had PCa in the validation cohort, 27 (71%), five (13%), one (3%), two (5%), and three (8%) had Gleason grade group 1, 2, 3, 4, and 5, respectively  were diagnosed with PCa and 165 (82%) were not. The median age was 66 yr (IQR 60–70) and 65 yr (IQR 59–69) for PCa and benign biopsies, respectively. The median PSA was 5.3 ng/ml (IQR 3.5–7.6) and 5.3 ng/ml (IQR 3.4–7.7), median PSAD was 0.13 ng/ml/cmectively .Table 1C3.1p < 0.05; In univariate analysis, family history of PCa, PSA density, and the 4Kscore emerged as significant predictors of PCa. In the multivariable analysis, family history of PCa, PSA density, and the 4Kscore were significantly associated with PCa and csPCa  for predicting PCa and csPCa was 0.80 and 0.87, respectively A,B. HereWe evaluated the nomogram calibration by comparing predicted and actual probabilities of PCa in the validation cohort. There was agreement between the predicted and actual rate of probabilities for PCa, as seen by points on the diagonal line in Using our model in the validation cohort, at a probability threshold of 10%, 10% of overall biopsies could be avoided without missing csPCa, avoiding 14% of benign biopsies . In addi4We developed a multivariable risk prediction tool for patients with negative MRI comprising age, family history of PCa, history of prior negative biopsy, 4Kscore, DRE finding, and PSA density to predict PCa and csPCa. Our model confers three key benefits. (1) The model can be used to avoid a significant number of biopsies among men with negative MRI without compromising detection of csPCa. (2) The model shows the efficacy of the 4Kscore, PSA density, and family history of PCa for predicting PCa and csPCa for men with negative MRI. (3) MRI misses 8% of csPCa cases. As diagnosis of csPCa is critical, the model addresses this gap.Our model results support the avoidance of a substantial number of biopsies without significantly missing csPCa among men with negative MRI. With the number of prostate biopsy procedures increasing every year, the complications associated with biopsy have attracted greater attention. Common nonfatal complications after biopsy include pain, bleeding, and voiding dysfunction. Postbiopsy fever and infection are less common, but can be potentially fatal complications 3) in men with negative MRI predicts csPCa A number of prediction calculators for diagnosing csPCa have been developed. Most of these tools include mpMRI as a variable, yet it remains unclear whether patients with negative MRI should undergo biopsy. Our findings show that men with elevated PSA density, elevated 4Kscore, and a family history of PCa should undergo prostate biopsy regardless of negative MRI findings. Elevated PSA density  and validation (11 csPCa cases) cohorts is a limitation of the study and may affect its applicability. Second, this is a retrospective, single-center study with a single biopsy expert and our outcomes may not be reproducible. In addition, the small number of events and the risk of overfitting for the proposed model with six variables may affect its generalizability and applicability. The 5We developed an easily accessible tool to help clinicians in biopsy decision-making and in counseling patients at risk of PCa with negative MRI. Use of this novel prediction model can significantly reduce the number of biopsies without markedly missing csPCa in men with a negative MRI examination. Our results show the significance of the 4Kscore, PSA density, and family history of PCa for predicting PCa and csPCa in men with negative MRI findings. The prediction model we have developed could provide valuable information for physicians and patients in assessing an individual’s risk for csPCa with negative MRI.Author contributions: Vinayak G. Wagaskar had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.Study concept and design: Tewari, Wagaskar.Acquisition of data: Wagaskar, Levy, Moody, Ratnani, Garcia.Analysis and interpretation of data: Wagaskar, Sobotka, Ratnani.Drafting of the manuscript: Wagaskar, Tewari, Wiklund, Levy, Punnen, Moody, Parekh, Pandav, Shukla, Pedraza, Prasad, Haines.Critical revision of the manuscript for important intellectual content: Wagaskar, Wiklund.Statistical analysis: Wagaskar, Ratnani, Sobotka.Obtaining funding: None.Administrative, technical, or material support: None.Supervision: Wagaskar.Other: None.Financial disclosures: Vinayak G. Wagaskar certifies that all conflicts of interest, including specific financial interests and relationships and affiliations relevant to the subject matter or materials discussed in the manuscript , are the following: None.Funding/Support and role of the sponsor: None.Acknowledgments: We thank Ms. Sima Rabinowitz for editorial assistance.Vinayak G. Wagaskar: Conceptualization, Methodology, Software, Writing - original draft. Micah Levy: Data curation, Writing - original draft. Parita Ratnani: Methodology, Software. Kate Moody: Data curation, Writing - original draft. Mariely Garcia: Data curation. Adriana M. Pedraza: Writing - original draft. Sneha Parekh: Writing - original draft. Krunal Pandav: Writing - original draft. Bhavya Shukla: Writing - original draft. Stanislaw Sobotka: Methodology, Software. Kenneth Haines: Data curation. Sanoj Punnen: Validation, Writing - review & editing. Peter Wiklund: Visualization, Investigation. Ash Tewari: Supervision, Investigation, Writing - review & editing.


Introduction: Stiffness following total knee arthroplasty (TKA) is a challenging complication and can result in a poor functional outcome. There is considerable debate concerning the definition, work-up, and optimal management of this complication. The aim of this study was to record the definition of stiffness, management practices, and expectations of outcome among surgeons from an international community using a peer-reviewed questionnaire. Methods: A 23-item peer-reviewed online questionnaire was sent to all members of SICOT to gauge and record the management practices and expectations of outcome in the management of patients with stiffness following TKA. Results: A total of 315 surgeons completed this peer-reviewed questionnaire. Manipulation under anaesthesia (MUA) was the preferred treatment option for stiffness post-TKA, with a majority of the surgeons opting to carry out this procedure between 6 and 12 weeks following the index TKA. Physiotherapy and a continuous passive motion device were also used by the majority of surgeons following MUA, as additional treatment measures. Discussion: MUA is perceived to be a safe and effective primary treatment option for stiffness following TKA. It is best performed between weeks 6 and 12 with expected gains in range of motion from 10 to 20 degrees in 75% of patients. Total knee arthroplasty (TKA) is being performed increasingly for treating end-stage arthritis of the knee . The lifPost-operative stiffness is defined as an inadequate ROM causing functional limitations in activities of daily living and occurs in approximately 5–6% of TKAs. And some studies report an incidence of up to 20% . HoweverStiffness following TKA can occur as a result of several conditions  with difCurrently, there is no clear definition of stiffness following TKA and a lack of a clear management algorithm, especially with the timing of MUA for stiffness. It is vital to understand the current management practices and expectations of outcomes concerning the management of stiffness following TKA across the international community. This would help surgeons have a better understanding of the management of this important problem.The aim of the study was therefore to (1) define stiffness following TKA and work-up for this problem, (2) analyse the timing of MUA for stiffness following TKA, (3) identify the different modalities and duration of rehabilitation used following MUA, (4) assess the improvement in ROM after MUA and recurrence of stiffness, (5) ascertain complications of MUA experienced by surgeons, and (6) different patient-reported outcome measures (PROMs) used and patient satisfaction.Supplementary Table 1s) was constructed and delivered through an online medium using Survey Monkey .A pilot survey was prepared following an in-house discussion of the research team addressing the study aims. This contained sections devoted to the surgeon’s current practice, including the diagnosis and investigation of stiffness, management options, rehabilitation protocol, and follow-up schedule. The questions were of a multiple-choice format, and the participants were encouraged to provide comments where necessary. The pilot survey was sent to an independent group of 20 senior knee arthroplasty surgeons in the UK, USA, Canada, and Australia. This process filtered ambiguities and the surgeons commented on the transparency and comprehensiveness of the questions, providing suggestions to improve the quality of the survey. The questionnaire was modified following the pilot survey and a final 23-item questionnaire-based survey  and Europe (35.6%). In addition, we received responses from Africa, North America, Australia, and South America . Forty pConsiderable variability was found among the participating surgeons in how they defined stiffness following TKA . There wThe majority of participating surgeons (90.2%) performed MUA for arthrofibrosis. With regards to the timing of MUA 54.6% considered that MUA for stiffness should be performed between 6 and 12 weeks following the index TKA, whereas 20.1% would perform MUA within the first 6 weeks, 17.4% between 12 and 20 weeks, and 7.8% would consider MUA after more than 20 weeks . A limitThe majority (95.5%) of the participating surgeons offered physiotherapy to their patients following MUA; 60.7% of the surgeons offered physiotherapy routinely for 6 weeks and 28.2% for up to 3 months. Additionally, 71.7% of the participants used a Continuous Passive Motion (CPM) device, with a varied duration of use. CPM was used by 38.8% for inpatients until the achievement of the target ROM, 16.9% of the patients were discharged home with CPM if necessary, to achieve target ROM and 15.8% used CPM only for inpatients irrespective of achievement of ROM.The participating surgeons who performed MUA for stiffness following TKA expected improvement in ROM, almost 75% of participants expected an improvement of a minimum of 10°–20°. A further sub-group analysis revealed that 31% of participants expected between 10° and 20° gain in the ROM, compared to 41% expecting 20°–30°, 14.8% expecting 30°–40° and 9.5% expecting >40° improvement in ROM following MUA.The perceived recurrence rate of stiffness following MUA varied among participating surgeons: 32% estimated that the recurrence rate was less than 1%, 26% estimated that it was 1–5%, 18.6% estimated that it was 5–10%, and 23.3% estimated recurrence in more than 10% of cases.In patients with recurrence of stiffness following MUA, nearly half (46.4%) of the participating surgeons elected not to perform a second MUA. Only 24.4% occasionally performed a second MUA and 17.7% would only perform a second MUA at the patient’s request. Thirty seven percent of the participants elected to combine MUA with arthroscopic arthrolysis, while 21.3% of participants would proceed to open arthrolysis and 12.9% would consider revision surgery if necessary. Additionally, 12.6% of the participants considered physiotherapy alone as appropriate management in case of a recurrence of stiffness.Manipulation under anaesthesia for stiffness following TKA was considered a safe procedure by the majority of participating surgeons, 71.9% estimated that the rate of complications including fracture, patella tendon rupture, and algodystrophy was less than 1%. The remainder of the participants estimated that their complication rates were 1–3% (19.4%) or more than 3% (8.7%).A variety of scoring systems were used to assess TKA outcomes among the participating surgeons. The most popular scoring system was the Knee Society System (61.9%), followed by the Oxford Knee Score (28.6%). The majority of participants (60%) estimated that their patients are either satisfied or very satisfied with the outcome of MUA for stiffness following TKA, 32.5% estimated their patients to be neutral with regard to MUA outcome and 7.5% estimated that the patients would be dissatisfied with the outcome.This is the first international survey that investigates the practices of orthopaedic surgeons concerning the diagnosis, investigation, and management of stiffness following TKA. We received responses from 315 orthopaedic surgeons, with varying experience, ranging from trainees to those with over 25 years of independent orthopaedic practice. The results revealed a wide variation in practice. Although 44.1% of the survey respondents performed less than 50 TKAs per year, the majority (55.9%) performed more than 50 TKAs per year including 9.8% who performed more than 250 TKAs per year . The parWe accept some limitations of our study. Firstly, electronic surveys are prone to a low response rate . We chosIn this survey there was a wide variation in how participants defined stiffness following TKA, reflecting the breadth of definitions in the current literature . In the The optimal timing of MUA after TKA is controversial . Some stYercan et al. proposed that thorough investigations be performed prior to MUA to rule out infection, algodystrophy, or surgical error which are contraindicated for MUA . AdditioIssa et al. reported that the mean gain in flexion following MUA in their study was 33°, ranging from 5° to 65°, with a gain of 36.5° for early MUA compared to 17° for late MUA . Our surAdditional use of CPM in combination with physiotherapy has been shown to be beneficial during the early rehabilitation phase following a primary TKA , 19. AltThere are four typical management options for stiffness following TKA. After MUA these are arthroscopic arthrolysis, open arthroscopic arthrolysis, and revision TKA , 10, 11.Even though MUA is a non-invasive procedure, it is crucial to ensure that the benefits outweigh the risks and possible complications. MUA is perceived to be a safe procedure with 71.8% of participating surgeons estimating a complication rate of less than 1% following MUA. The complications for each of the procedure is listed in This is the first study to assess the management preferences of surgeons across the globe towards stiffness following TKA. The participating surgeons had different levels of experience both in terms of years in independent practice and the number of TKAs performed annually, which can be generalized to the whole orthopaedic community. In addition, the final questionnaire was devised following a preliminary validity assessment of the pilot survey by 20 senior knee arthroplasty surgeons from the International Community.A timely accurate diagnosis of stiffness following total knee arthroplasty is essential to appropriately manage the condition and ensure good patient satisfaction. A simplified treatment algorithm is shown in Stiffness is a well-recognized complication following TKA, which can result in a poor functional outcome. A thorough evaluation of patients with a stiff knee following TKA is essential to correctly diagnose arthrofibrosis as the cause of stiffness. MUA is widely recognized as the optimal first-line treatment to improve ROM in postoperative arthrofibrosis. Improvement in ROM of 10° to 20° can be expected in 75% of patients. Post-operative physiotherapy for 6–12 weeks is believed to be useful to maintain the gain in ROM. In cases where there is a recurrence of stiffness following MUA, our survey suggests a second MUA with or without arthrolysis should be considered. MUA is perceived as a safe procedure with a low complication rate, where a good functional outcome can be expected.https://www.sicot-j.org/10.1051/sicotj/2021008.The supplementary material of this article is available at Table 1s. International Survey on Surgeon Preferences in the Management of Stiffness following Total Knee Arthroplasty.All authors declare that they have no conflict of interest for the submitted work and have received no funding for this work.KHSK – Chair of SICOT Young Surgeons Committee.VK – Educational consultant Smith & Nephew & Arthrex, Chair SICOT Education Academy, President Elect British Hip Society, Past Chair – NAHR UK.


Improvement of SV graft patency rate is therefore a great challenge in the field of cardiovascular surgery. The widespread use of complete arterial grafting with the left internal thoracic artery and other arterial conduits cannot yet be justified on scientific grounds, as there are few late survival data and controlled studies to support this statement.For many reasons, the saphenous vein (SV) and internal thoracic artery (ITA) will continue to be the most important conduits in coronary artery bypass grafting (CABG). The high incidence of vein graft occlusion is an important and unsolved problem in myocardial revascularization. At time of implantation, adventitial and endothelial damage is almost absent in ITA grafts. In contrast, the endothelium of conventionally-harvested SV shows greater thrombogenic properties and the SV adventitial layer is often completely removed during the operation,5. Usually, the vein is harvested traumatically by a junior of the surgical team, with least experience, a situation likely to contribute to the poor quality of the graft and consequently to graft failure.Different structural and functional properties between arteries and veins may explain the better results of the arterial grafts. Nevertheless, the trauma to the SV wall that occurs during its harvesting for CABG may also contribute to the poor results of venous grafts.Many strategies have been introduced in an attempt to prevent vein graft occlusion and to improve short- and long-term patency rate. Apart from established adjuvant medical therapy, new pharmacological agents, gene therapy, as well as mechanical devices are presently undergoing evaluation. Many of these strategies have shown promise in experimental vein bypass models. However, few have successfully been translated into clinical practice. We believe that these approaches represent the familiar scenario of closing the stable door after the horse has bolted. Surely, it is more desirable to prevent damage to the vein in the first place than to correct the damage once it has been inflicted. This damage leads to neointimal hyperplasia and other aspects of graft failure. There is a wealth of literature showing the adverse effects of surgical trauma, especially the harmful effects of high pressure distension that is often used during vein graft harvesting and the subsequent fate of the vein graft. The main aim, when applying NT harvesting, is to maintain the structural and functional integrity of the vein wall and consequently to improve SV graft outcome. After a few pilot cases, a randomized single-center clinical trial was initiated in 1993 to compare conventional saphenous vein grafts with no-touch saphenous vein grafts (NTSVG). In this trial, we followed the patients over three different time points; at mean time 1.5, 8.5, and 16 years after the operations. The results of this trial showed favourable for the NT technique regarding both angiographic and clinical outcomes. Parallel to the clinical trials many basic research studies were performed in the Dashwood laboratory at the Royal Free Hospital/University College London, United Kingdom. These studies have revealed certain mechanisms underlying the improved performance of NTSVGs, in particular the protective role of the perivascular fat (PVF) that preserves both structural integrity and functional properties of the vein wall-11.The no-touch (NT) technique, where the SV is harvested with its pedicle of surrounding tissue intact, was developed in the early 1990s by Domingos Souza in the department of Anesthesiology and Cardiothoracic Surgery at Örebro University Hospital, Sweden,5,10. Furthermore, endothelial integrity was better maintained using the NTSVG. Nitric oxide synthase activity was preserved on the endothelium and was derived from both neuronal and adventitial microvessel sources, suggesting that nitric oxide (NO) availability is retained by these grafts. The vasorelaxant and thromboresistant activities of NO may be responsible for the reduced spasm and the observed improvement of the patency rate of NTSVGs,10. In addition, the surrounding tissue possesses mechanical properties that supports excessively long vein grafts and prevents kinking.Based on our results, it was concluded that the method of harvesting greatly influences the fate of the SV graft. The PVF and adventitial layer contain structures possessing both mechanical and functional properties that protect the vein from spasm and ischemia,13), Japan, China, and South Korea. Currently, two large randomized multicenter trials are ongoing to evaluate the NT technique. The first one is being performed in China, which included 2,655 patients and the one-year results was recently published. The second similar ongoing randomized trial is in Sweden and 900 patients were included. However, the data of this trial will not be analyzed until 2023. The results of these studies are expected to be of great value for the further spread and adoption of the NT technique particularly because any improvement in SV graft performance needs to be easily applied as well as provides similar good results in the majority of cardiac centers worldwide.Initially there appeared little acceptance for this technique with it being used solely in the department of thoracic and cardiac surgery at Örebro University Hospital, where it was developed. Following publication of both the randomized clinical trials and the basic science studies, considerable interest has been raised worldwide whereby the NT technique is recognized and has been adopted in many countries, especially in Sweden.Following the first publication describing the NT technique, this technique has been the subject of four theses and many publications from around the world. Furthermore, NTSVG has been referred to in many articles published in peer-reviewed journals. Some years passed before the advantages of the NTSVG technique was recognized, and today it is ranked as class IIa in the European Society of Cardiology/European Association for Cardio-Thoracic Surgery Guidelines on myocardial revascularization. This allows us to make the skin incision exactly above the vein, thereby reducing soft tissue injury and the creation of flap tissues. In addition, this procedure allows selection of the best vein segments suitable for grafting.Concerns have been raised regarding the issue of increased leg-wound infection. The NT technique consists not only of harvesting the vein with a fat pedicle intact but also of other important steps, one of which is to preoperatively mark the course of the vein on the overlying skin by using an ultrasonographic doppler assessment, we have managed to reduce wound healing complications considerably. It would certainly be preferable to obtain a conduit with a longer patency, even if there is a higher risk of wound infection. The ideal situation would be to obtain a superior conduit combined with minimal risk of harvesting site infection. Therefore, development of a minimally invasive endoscopic technique for harvesting the NT veins is essential in order for the NT technique to be more widely accepted. Fortunately, a number of recent publications have addressed this important issue whereby the SV is removed with minimal vascular damage, with PVF intact, and reduced wound complications.By implementing the technique as described previouslyAfter all scientific evidence during the last 30 years, the NT SV should be recognized as a very important conduit for CABG surgery.


The wear behavior of the novel zirconia generation is less well understood and may be affected by compositional modifications compared to the conventional zirconia.  Combinations of keywords such as “zirconia,” “high translucent,” and “wear” were searched in PubMed and Google Scholar databases up to May 2021. The total of 23 relevant articles was selected according to inclusion criteria.  Reports show comparable wear resistance of translucent zirconia to the conventional zirconia despite an increased cubic phase content and lower mean flexural strength. A meticulously polished surface creates the lowest surface roughness, producing favorable zirconia wear resistance and antagonist wear compared to a glazed surface. In comparison to other ceramic materials, zirconia produces the least wear on an enamel antagonist and almost undetectable wear when opposed by zirconia. Wear when paired against resin materials yields a favorable outcome, whereas wear behavior against a metal antagonist varies with the surface hardness of the metal.  All zirconia generations are considered wear-friendly to all types of antagonists. Nonetheless, comparative studies on antagonist wear opposing zirconia of different compositions are still limited and further investigation is required. With a rising demand from patients for highly esthetic dental restorations, various tooth-colored restorative materials have been introduced in the past decades. Zirconia rapidly gained popularity due to several advantages including good esthetics, biocompatibility, and outstanding mechanical properties comparing to other ceramic systems. In addition, increasing prices of precious alloys and mechanical failure of metal-ceramic restorations have made zirconia a novel restoration of choice.Three generations of zirconia have been developed to date. Initially, conventional 3Y-TZP  was utilized as a framework material that was veneered by more conventional ceramics to achieve an esthetic result, as this first-generation dental zirconia was very opaque. Its high strength allowed multiunit applications, but chipping and failure of the weaker veneering ceramic were common. The latter two generations, shared termed “high-translucency” zirconia, aim to overcome esthetic problems, namely, high opacity, exhibited by previous generations of zirconia. Improved translucency of zirconia from the second generation was achieved through reduction of alumina additive content to 0.05% by weight while yttrium oxide stabilizer remains unchanged at 3% by mol (4.5–5.6% by weight) . FurtherInvestigation of opposing enamel and restoration surface wear is of equal importance. Conventional wisdom, based on wear of feldspathic ceramics opposing natural dentition, has suggested that a new zirconia restoration should not be placed opposing unrestored enamel surfaces. Likewise, interaction of zirconia restoration with other types of restorative material was concerned. Additionally, wear resistance of the zirconia restorations itself is noteworthy. Therefore, our review aims to discuss the wear behavior of zirconia as well as its opposing materials and provide evidence that will be useful for making a clinical decision when selecting the appropriate material for fixed restorations.in vitro and in vivo, involving wear of monolithic zirconia and its opposing materials of any types were included. The publication must be in English language. Case report and non-peer-reviewed articles were excluded. From all search results appeared on the database, only 23 available articles were selected after analyzing for relevant titles and abstracts. The flowchart of article selection is illustrated in A literature search of electronic databases was conducted using PubMed and Google Scholar databases up to May 2021. The search keywords included combinations of terms such as “zirconia,” “high-translucent,” and “wear.” Experimental studies, both Zirconia material is originally known for its superior flexural strength and surface hardness. High surface hardness was expected to produce more antagonist wear , 3. This2) is a polymorphic material existing in three crystalline phases: monoclinic, tetragonal, and cubic (c phase) during cooling first at temperatures below 2,680°C. It then transforms to the tetragonal phase (t phase) at 2,370°C and lastly to the monoclinic phase (m phase) under 1,770°C. The latter phase transformation causes volumetric expansion of approximately 4%. Such sudden change in volume creates high tension and undesirable crack formation in the ceramic. Initially, 3 mol% yttria or yttrium oxide was added to zirconia to prevent this phase transformation [Zirconia or zirconium dioxide  or aging. This phenomenon happens slowly from water penetration into crystalline structure at 200–400°C well below sintering temperature. Repeated exposure to warm and humid environment gradually transforms phases of zirconia from tetragonal to monoclinic. The rate of LTD, stated in a study by Koenig et al. in 2006, is approximately 15 years or comparable to the mean lifespan of dental restorations . Phase tAn addition of alumina content of at least 0.15 wt% helps reduce low-temperature degradation. Reduction of alumina content to enhance zirconia translucency can increase predisposition to LTD. Nevertheless, alumina sintering additives also lead to higher opacity, a competing outcome for dental use.The first generation of zirconia was introduced to dentistry over two decades ago as yttria-stabilized tetragonal zirconia polycrystal (Y-TZP). It contains 3%mol of yttria with at least 90 percent of tetragonal zirconia, giving its name, 3Y-TZP. Despite superior mechanical property with flexural strength over 1000 MPa , this geThe second generation of zirconia was proposed to solve the frequent chipping problem as a monolithic or single-layered restoration . FurtherThe third and the latest generation of zirconia exhibits a modified crystalline structure containing increased percentages of cubic phase in pursuit of even greater translucency. “High-translucent” or “ultratranslucent” zirconia refers to this specific generation. The geometry of different zirconia phases affects light transmission behavior and translucency. The tetragonal phase has birefringent properties, or anisotropic refractory index, which results in a greater amount of light scattering at grain boundaries. On the other hand, the cubic phase has isotropic refractory index without scattering effect which offers better translucency.Increasing the content of yttria to 4% and 5% mol results in higher nontransformable cubic phase and lesser tetragonal phase, consequently increasing translucency. Elemental analysis through X-ray diffraction (XRD) by Zhang et al. revealed about 40% and 60% of cubic phase content in 4Y- and 5Y-TZP, respectively . Other sIt is noteworthy that there are some confusions on the term “translucent zirconia” since both second and third generations are frequently called by the same nomenclature. The term “monolithic zirconia” without any further description is normally referred to 3Y-TZP from the second generations, while studies on the third generation are usually more specific –24. HoweImprovement in translucency of 5Y-TZP was evaluated in multiple studies , 26, 27.The mechanical properties of high-translucency zirconia are manufacturer-dependent. Even though increased cubic phase enhances translucency, it negatively influences strength of high-translucent zirconia. Cubic zirconia does not possess the transformation toughening phenomenon as does tetragonal zirconia. Less transformation can be detected in 4Y-TZP, but no evidence is shown in 5Y-TZP . The depThe transformation toughening phenomenon is a unique property which contributes to the high strength of 3Y-TZP zirconia by reducing crack propagation and increasing fracture toughness , 9. Thisµm per year in molar area and relatively lesser as the position in arch moves anteriorly [In terms of occlusal wear, ideal restorative materials should possess a similar wear rate to physiological enamel wear rate which ranges from 30 to 40 teriorly , 38. A mteriorly , 40. TwoWear mechanism is multifactorial. Physiological variations among patients and material-based factors both play an important role in the wear process. Factors influencing wear of ceramics were thoroughly reviewed by Oh et al. in 2002 including physical factors, microstructural factors, chemical factors, and surface finishing .Ceramic materials have low resistance to tensile stress due to their brittle nature, which leads to surface chipping or fracture either from physiologic wear or iatrogenic surface adjustment . With itFrictional coefficient, a ratio of frictional force between two sliding surfaces in relation to the normal force pressing the two surfaces together, is varied by occlusal anatomical variations, degree of mandibular movement, masticatory load, chewing rate, types of contacting materials, and surrounding environment . PatientIrregularities in a ceramic surface contribute to surface roughness which can significantly accentuate antagonist wear in ceramic material itself and the opposing surface , 42, 43.Differences between the microstructures of glass ceramics and polycrystalline ceramics contribute to the difference in their wear behavior and wear mechanism. Glass ceramics are composed of crystalline particles incorporated into glassy matrix. Their principal wear mechanism relies on fatigue fracture of the glassy matrix with consequent exposure and loss of embedded crystalline phase . VariatiBesides surface irregularities generated from functional wear, defects and porosities from the manufacturing process also aggravate the wear process on opposing surfaces once subsurface pores are exposed, leading to sharp asperities , 52.Variations in pH values affect zirconia in a different way. In one study, low coefficients of friction and wear rates were observed in acidic environments below pH 4. The surface roughness of zirconia was not affected and actually decreased after exposure to acid, owing to a tribocorrosion process . In contSurface finishing is associated with surface roughness and wear of zirconia. Comparison of glazed and polished surfaces has been widely studied. Most of the studies on zirconia surface finishing are in agreement with the polishing methods used to produce the least wear of the zirconia itself and the antagonist , 56–62. µm grit bur produces statistically comparable wear of opposing enamel as that of polished zirconia, while adjustment with a coarse 100 µm grit bur generates substantially increased wear [µm, but for a coarse diamond bur, surface roughness is reported to be as high as 3.95 µm. The threshold value of ceramic surface roughness (Ra) that significantly raises enamel wear based on several studies is over 1.5 µm [µm grit bur vs. zirconia polishing burs, a statistically significant decrease in surface roughness and wear was reported from polishing [µm [t-m phase transformation [Different polishing systems and polishing protocols by researchers produce varying degrees of surface roughness. The grit of diamond bur used for adjustment also correlates to postadjustment surface roughness. Adjustment of zirconia with a fine 30 sed wear . A fine r 1.5 µm , 65, 66.olishing . Regardiolishing , 68. A mhing [µm , 63, 69.ormation , 68, 69.ormation . Even ifApplication of external staining material is another factor promoting wear since the composition of extrinsic stains contains abrasive metal oxides . The surStudies on various dental restorative materials have stated that materials with high strength and high fracture toughness showed minimal material wear or antagonist wear , 51, 58.Concerns involving surface stability have led to studies evaluating wear behavior among the different zirconia generations. Most of the previously published studies were conducted with 3Y-TZP, and there is little information on wear behavior of high-translucent zirconia with increased yttria content. However, a few recent studies have compared wear behavior between 3% mol and 4-5% mol yttria-stabilized zirconia –24, 47. It can be assumed that wear behavior is relatively unaffected by microstructural variations between zirconia generations and zirconia with increased yttria content is able to maintain good surface integrity despite lower flexural strength and fracture toughness , 24, 47.Wear resistance of zirconia compared to other restorative materials has been extensively studied. A wide range of antagonist materials have been used, including enamel substitutions, such as steatite ball or IPS Empress, bovine enamel, both nonstandardized and standardized human enamel, and zirconia itself. Studies on antagonist material wear against zirconia are listed in In vivo studies on enamel wear opposing a monolithic zirconia crown found that average vertical wear of the enamel antagonist was considerably higher than the contralateral enamel controls at the same time interval [in vitro studies suggests that monolithic zirconia produced the least wear on enamel compared to other ceramics [interval , 74, 75.ceramics , 73, 83.The wear behavior of zirconia restorations opposed by dental materials other than human enamel is of equal significance. Unrestored opposing teeth are occasionally found. Comparative studies of various types of restorative materials when used against zirconia have also been performed , 78–82.(1) Ceramics. The in vitro wear rate of various types of ceramics opposing a zirconia abrader has been studied. The level of surface wear is associated with the materials' flexural strength, fracture toughness, and microstructure. Glass and hybrid ceramics consist of crystal grains loosely bound in glassy or polymeric matrices. According to the brittle nature of ceramics, the wear mechanism is primarily via fatigue wear [gue wear . Gradualgue wear . Furthergue wear . Accordigue wear , 78.(2) Metal. Existing metal restorations in good condition may serve many years in function without the need for replacement. Caution must be exercised when a new zirconia restoration is contemplated being placed opposing an existing metal alloy restoration in terms of wear. Unlike ceramics, the wear mechanism of metal is associated with surface hardness and plastic deformation [ormation , 5. The ormation . Neverthormation . Base meormation . SEM imaormation .(3) Polymer and Composite. Use of different materials in full-arch implant-supported prostheses may be advocated to limit mechanical complications in the opposing, weaker arch. Accordingly, denture teeth supported by a metal framework are often chosen as an antagonist against a zirconia full-arch implant-supported prosthesis [osthesis , 85.The chemical compositions of resin matrix and filler in denture teeth influence their wear resistance. Modification in composition and fabrication technique has been used by manufacturers to improve the strength and wear resistance of conventional polymethyl methacrylate (PMMA) denture teeth. CAD/CAM-fabricated and 3D-printed denture teeth have shown comparable wear resistance to prefabricated PMMA denture teeth against a zirconia abrader , 82. 3D-The size and configuration of the filler particles themselves play an important role in the level of wear of resin composite. When abraded against a zirconia antagonist, microhybrid resin composite experienced higher volumetric substance loss as a consequence of its mixture of larger filler size and irregular filler shape compared to nanofilled resin composite.Enamel wear against zirconia is considered clinically acceptable when zirconia is meticulously polished.In a situation where ceramic restorations are required on opposing occluding surfaces, zirconia placed against itself provides the best wear resistance, while choosing different types of ceramics can predispose the materials to greater wear.Placement of 3Y-TZP zirconia opposing a gold alloy restoration may result in increased wear on the gold alloy. On the contrary, placing zirconia against Co-Cr alloy is neither recommended since phase transformation is expected in 3Y-TZP zirconia.Filled composite resin denture teeth have improved wear resistance against 3Y-TZP zirconia restoration compared to unfilled PMMA denture teeth both prefabricated and CAD/CAM fabricated.Translucent zirconia compositions with increased yttria content (4Y- and 5Y-TZP), despite having different microstructural compositions, lower flexural strength, and lower fracture toughness, suggest equivalent wear resistance as conventional 3Y-TZP from the literature revised.Comparative studies evaluating wear of antagonist materials against zirconia compositions of different yttria content are still lacking. In the future, authors should be very specific in stating the zirconia composition used in scientific studies. Further studies regarding this issue are required.Based on this review of the literature, the following assumptions were drawn:


Surface morphology and chemical analysis were studied using a scanning electron microscope and energy-dispersive spectroscopy. Surface roughness was evaluated using a profilometer. Surface hardness was measured using an indentation tester. For the microshear bond strength test, resin cement cylinders were bonded to a zirconia surface. Half of the specimens were tested after 24 h; the other half were thermocycled (5–55 °C) for 1000 cycles. A shearing load was applied at a crosshead speed of 0.5 mm/min on a universal testing machine. Data were analyzed with ANOVA using SPSS software at (p < 0.05). Results: tThe mean surface roughness of G II was significantly higher than G I and G III. The microhardness of G II was significantly lower than all groups. For bond strength, there was no significant difference between groups II, III, and IV after thermocycling. Conclusions: Bioactive glass can increase the bond strength of zirconia to resin cement, and is comparable to sandblasting and Z-prime bonding agents.This study aimed to assess bioglass sintering to a zirconia core on surface properties and bonding strength to resin cement. Zirconia specimens were divided into four groups: G I: sintered; G II: bioglass modified zirconia (a bioglass slurry was sintered with zirconia at 1550 °C); G III: sandblasted using 50 μm Al The development of high-strength zirconia is one of the recent advances in ceramic dental materials. Zirconia materials deliver speculatively higher fracture resistance and durability, as compared with porcelain and other nonmetallic alternatives . ZirconiDespite the superior mechanical properties of zirconia, one main obstacle is its weak bonding to different synthetic and nonsynthetic substrates due to its inert state. Thus, it cannot provide adequate bond strength following conventional cementation techniques .Researchers have evaluated the strength and durability of different bonding protocols. A commonly used technique to increase the zirconia bond strength to resin cement is sandblasting (air abrasion). Using aluminum oxide particles in air abrasion is a conventionally used method to eliminate the superficial contaminated layers and increase micromechanical retention between composite cement and restoration . However4-ester monomer usage [Other protocols used for improvement of bond strength are tribo-chemical silica coating, glass micro-pearl silica-coating, selective infiltration etching, hot etching, laser irradiation, and POer usage .The bond strength of silica-based materials such as porcelain can be increased effectively by silane. However, a silane coupling agent alone is not efficient for zirconia bonding (non-silica-based restorations); these restorations require surface treatment before bonding. Likewise, hydrofluoric acid (HF) etching and silanization techniques are not effective for zirconia bonding enhancement .2, 24.5% Na2O, 24.4% CaO, and 6% P2O5. Its composition is still among the most examined bioactive glass, and has been investigated for about 50 years [+ and/or Ca2+ with H+ from solution, creating silanol bonds (Si–OH) on the glass surface, The pH of the solution increases, and a silica-rich (cation-depleted) region forms near the glass surface. Phosphate is also lost from the glass if present in the composition. Then, the high local pH leads to an attack of the silica network by OH−, breaking the Si–O–Si bonds. Soluble silica is lost in the form of Si(OH)4 to the solution, leaving more Si–OH (silanols) at the glass–solution interface.Bioactive glass is well defined as a surface-reactive inorganic material. Crystalline phases can be produced by some bioactive glasses during thermal processing that reduce the degradation rate. Bioactive glasses can be used for enamel remineralization and bone regeneration ,9. The f50 years . The bio2+ and PO43− groups to the surface through the silica-rich layer and from the solution forms a film rich in amorphous CaO–P2O5 on the silica-rich layer. The final stage is an incorporation of hydroxyls and carbonate from solution and crystallization of the CaO–P2O5 film to HCA [Later, the condensation of Si–OH groups near the glass surface and repolymerization of the silica-rich layer occur. After that, the migration of Cam to HCA ,12.Another effective method used for surface activation of zirconia is the application of a primer that has acceptable cost and simple application. Primers that contain the composition of 10-methacryloxydecyl dihydrogen phosphate (MDP) and phosphate monomers can enhance zirconia’s bonding ability . ImproveMeasurement of bond strength is used to assess the effectiveness of an adhesive system and to subsequently predict its clinical application. The most commonly used types of bond-strength tests are of tensile and shear bond strengths. Researchers have described that cohesive fractures more frequently occur with shear bond strength rather than adhesive fractures. In clinical situations, cohesive failures are hardly detected in bonded restorations . The strConsidering the sophistication of most procedures used to enhance zirconia/resin cement bond strength, this study was conducted to evaluate the effect of sintering bioglass together with soft-machined zirconia on the zirconia’s bonding ability to self-adhesive resin cements. The null hypothesis was that bioglass modification would nonsignificantly affect the zirconia/resin cement bond strength.For this in vitro study, a zirconia core  was used. The composition of all materials utilized in the study is listed in 2, 24.5 wt % Na2O, 24.4 wt % CaO, and 6 wt % P2O5 .The bioglass particles were synthesized using the alkoxide sol–gel technique; silicon and phosphorus alkoxides were used with calcium hydroxide and sodium hydroxide. Deionized water and ethanol were used as solvents, and the resultant gel was aged for one week at 70 °C at a pH of 2. It was heat-treated at a temperature of 800 °C. Particles were spherical had an average size of 44 µm, containing 45 wt % SiOBioglass powder (500 μg) was mixed with 0.2 mL of distilled water on a glass slab with a spatula to obtain a slurry mix and smeared onto the zirconia plates’ surface with a medium-sized bonding brush . The slurry penetrated between the partially sintered zirconia particles by capillary action, and thus no changes in the thickness were considered. The sintering process occurred at 1550 °C, according to a cycle recommended by the manufacturer, in a sintering furnace ; this was marked as the bioglass-modified zirconia group (BMZ) G II.n = 28) according to treatment methods as follows: G I: control (sintered only); G II: bioglass-modified zirconia; G III: sintered then sandblasted; and G IV: sintered, sandblasted, then the Z-Prime Plus application. All study groups were sintered first at 1550 °C, as recommended by the manufacturer, in a sintering furnace . Sandblasting was done using a sandblaster apparatus  using 50 μm Al2O3 particles at 2 bar pressure for 10 s, then rinsing in an ultrasonic cleaner device  for 60 min with distilled water and drying with an air syringe. For group IV, 28 zirconia plates were sintered, sandblasted, then treated with Z-Prime Plus  primer according to the manufacturer’s recommendation by applying 2 coats of Z-Prime Plus to the zirconia surface, and then drying for 3–5 s with an air syringe.For this in vitro study, zirconia plates were machined using low-speed diamond saw technology . Specimens were allocated into four equal groups . For this purpose, a representative specimen from each group was cleaned in an ultrasonic bath with 96% ethanol for 2 min and then air dried. Afterward, specimens were affixed on metallic stubs, coated  by gold sputtering to render the surface conductive, and examined by SEM to detect surface topography at different magnifications. Energy-dispersive spectroscopy (EDS)  was employed to investigate the elemental composition of all groups. The working distance and voltage used during the surface scanning was 15 mm and 20 V, respectively.Seven specimens were randomly selected from each group to measure the average surface roughness (Ra) by a profilometer . The stylus moved back and forth across each specimen; five readings were recorded, and the average roughness value (Ra) was calculated. The cut-off length was 0.8 mm, at a 0.5 mm/s scanning speed. The resolution of the recorded data was 0.01 µm.2, where P is the applied load (g) and d is the average length of the indentations’ diagonals (μm).Seven specimens were randomly selected from each group to measure the surface hardness at room temperature by the micro-Vickers hardness tester . An indentation was made on the surface under a load of 200 g for 15 s using a diamond micro-indenter in the shape of a pyramid with a 136° angle between its faces. The Vickers hardness number (VHN) was automatically calculated using the following equation: VHN = 1854.4P/d2 irradiance, a 430–480 nm wavelength, and a 10 mm tip diameter. The irradiance of the curing unit was calibrated by an Apoza radiometer , and the resin was thoroughly cured through a clear tube. Subsequently, the specimens were stored in 37 °C water for 24 h. Half of the specimens were tested after 24 h, and the other half were aged and thermocycled for 1000 cycles between 5 °C and 55 °C water baths. The dwell time at each temperature was 30 s, with a transfer time of 15 s . The thermocycling conditions were based on the calculation that 1000 cycles would simulate the situation during one year in the oral cavity. After thermocycling, specimens were tempered to room temperature.A low-viscosity self-adhesive resin composite cement  was filled into a cut tube of a Nelaton catheter  with an interior diameter of 1.98 mm and a height of approximately 1 mm. The tube was securely held on the specimen’s surface using a tweezer to prevent the resin from seeping away from the defined area at the base. Then, the automixed self-adhesive resin cement was filled and cured for 20s  according to the manufacturer’s recommendation with 1400 mW/cmPrior to testing, specimens were inspected under (×40) magnification of an optical microscope for any defects. Specimens with remarked surface gaps, bubbles, or other noticeable defects were excluded. The zirconia–resin cement bonds were consequently tested.A bonded specimen with composite micro-cylinders was mounted in a holding device and secured to the stationary part of a materials testing machine . A loop made of a nitinol orthodontic wire with a diameter of 0.014 in was used to wrap the cylinder very close to its bonded base and aligned parallel to the loading axis of the upper mobile part of the universal testing machine. A shearing load was applied at a 0.5 mm/min crosshead speed. The chosen slow crosshead aimed to produce a shearing force during micro-cylinder debonding along the zirconia–resin interface. The debonding load was recorded in Newtons.2): τ = P/πr2, where:τ = bond strength (MPa);P = load at failure (N);π = 3.14;r = radius of the microcylinder.To calculate the microshear bond strength, the failure load in (N) was divided by bonding area  under a stereomicroscope  at magnification of ×40. The failure modes were classified as cohesive failure, which referred to a complete fracture within the ceramic or within the composite resin; adhesive failure; which meant a fracture between the ceramic (or composite resin) and bonding agent; and mixed fracture; which indicated a fracture involving two materials.p < 0.05.All data were obtained as mean ± standard deviation and studied by an ANOVA test, using version 20.0 of SPSS software for Windows. When significant differences were found between the groups, a Bonferroni post hoc test was applied. The level of significance was set at Scanning electron photomicrographs of all groups at different magnifications are shown in The energy-dispersive X-ray results for all groups are shown in p = 0.00), while the sintered and sandblasted groups had an insignificant difference (p = 0.339).It is shown in −2) belonged to the sandblasted zirconia group (1853.21 ± 201.44), and the lowest microhardness value belonged to the bioglass-modified zirconia (951.70 ± 170.81). One-way ANOVA followed by a post hoc test showed that the Z-Prime group was statistically nonsignificant compared to the sintered group (p = 0.622). The bioglass group showed a statistically significant lower value than the sintered and sandblasted groups (p = 0.000), and also showed a statistically significant lower value than the Z-Prime group at p = 0.032. The sandblasted group showed statistically significant higher values than the sintered and Z-Prime groups, where p = 0.020 and p = 0.013, respectively.It is shown in p = 0.000. Group I had a significantly lower microshear bond strength than all other study groups, before and after thermocycling. The μSBS did not significantly decrease after thermocycling in the sintered and sandblasted groups, while in the bioglass and Z-Prime groups, the μSBS significantly decreased after thermocycling, as shown in Examining the debonded surfaces under a stereomicroscope showed that the mode of failure was prominently adhesive failure throughout all the examined specimens; however, the bioglass group before thermocycling showed mixed failure, and the Z-Prime group before thermocycling showed cohesive failure .In this in vitro study, bioglass material was sintered simultaneously with a zirconia substrate to form an adhesive layer, then characterized for its morphology, chemical structure, surface roughness, and hardness. Later, the microshear bond strength of bioglass-modified zirconia to resin cement was evaluated and compared to sandblasted and Z-Prime bonded groups, with the mechanical and chemical surface treatments being positive controls. In this study, the null hypothesis was rejected, as the bioglass-modified zirconia affected the resin cement/zirconia bond strength significantly.In the present study, the creation of a continuous etchable bioglass layer on the zirconia surface was made by applying a bioglass slurry onto the soft-machined zirconia substrate; then the zirconia core and bioglass slurry were simultaneously sintered, creating a bioglass-modified zirconia structure. This eliminated the fear of debonding and delamination that could occur if the bioglass was applied secondary after zirconia sintering, as a separate layer of coating. In this study a self-etching, self-adhesive resin cement was used to produce an adhesive surface with the least required clinical steps, by omitting the etching step and decreasing the technique sensitivity.This novel procedure of sintering bioglass and zirconia in the same furnace sintering cycle showed a homogeneous bubbly surface consisting of Zr, Si, and Ca, as confirmed by SEM and EDS. Scanning electron photomicrographs of the bioglass-modified group showed the development of a silica-rich glass layer with homogeneously distributed, evenly sized porosities E–H. This2 and CaO sintered particles over the machined zirconia was confirmed by the EDS analysis, and is shown in In the current study, the bioglass-modified zirconia specimens showed a significantly higher surface roughness than the sandblasted group. As when the bioglass slurry was applied to the soft-machined zirconia surface and the sintering process took place, amounts of glass particles were melted and diffused between the zirconia granules, and therefore surface irregularities were seen on the surface. The presence of SiO2O3 particles within the abraded surface, as confirmed by the EDS chemical analysis results  was selected to be used in this in vitro study .The Z-Prime Plus treatment group showed a higher statistically significant bond strength than the sintered group before and after thermocycling; this might be related to the chemistry of the Z-Prime material; as it bonded chemically to the zirconia structure. In addition, its surface morphology showed characteristic homogenous features and porosity. The Z-Prime Plus group also had significantly higher bond strength values due to its chemical structure, which contained conventional MDP and carboxylic monomers, which could chemically react with the zirconia oxide layer at the interface, as documented by the presence of a higher percentage of carbon by EDS . The intIn our study, the sandblasted group was considered the positive control group, since this process is considered the most efficient zirconia treatment, as it produces micro-mechanical interlocking of the resin cement by increasing the zirconia’s surface roughness ,23. In tIn this study, 1000 cycles were performed to simulate intra-oral environmental aging conditions. One limitation of this study was the short storage period that did not allow for water saturation in the luting resin and at the bonding interfaces; hence, the long-term hydrolytic durability of the bonding interface was not tested. Therefore, long-term water storage for 150 days and 37,500 thermocycles until water saturation of bonded specimens should be performed in order to differentiate between clinically durable and nondurable ceramic bonding systems .In the current study, there was a significantly higher microshear bond strength in the sandblasted, bioglass, and Z-Prime groups before thermocycling, which may be credited to the characteristics of surface roughness created in the bioglass and Z-Prime groups, as well as the silica contents documented in the chemical analysis of the bioglass layer. Z-Prime bonding agents containing MDP improved the bonding of resin cement to the zirconia ceramic . After tEvaluating the failure mode of the resin–zirconia interface showed that most splits were cohesive in the Z-Prime group. The bioglass-modified zirconia group showed predominantly mixed and cohesive modes, while the frequency of adhesive failures increased in all other groups. There were neither cracks nor fractures at the bioglass surface, showing that the bond between the bioglass and zirconia was stronger than the bond between resin and bioglass.From this in vitro study, it was possible to conclude that the use of bioactive bioglass to modify the zirconia surface during sintering was a feasible technique that could form a silica-rich layer. This sintered bioglass increased the zirconia’s surface roughness and reduced its microhardness. The use of bioactive bioglass to modify the zirconia surface could effectively increase the zirconia/resin cement bond strength, and could be an alternative to the already-established techniques, with the mode of failure being mixed before thermocycling.Additional research is still compulsory, especially to assess the fracture resistance of zirconia crowns after sintering with bioglass materials in the intaglio surface. An in vivo study will be also conducted in the future.


Rice production systems and soil characteristics play a crucial role in determining its yield and grain quality. Two elite Thai rice cultivars, namely, KDML105 and RD6, were cultivated in two production systems with distinct soil characteristics, including net-house pot production and open-field production. Under open-field system, KDML105 and RD6 had greater panicle number, total grain weight, 100-grain weight, grain size, and dimension than those grown in the net-house. The amounts of reducing sugar and long amylopectin branch chains (DP 25–36) of the RD6 grains along with the amounts of long branch chains (DP 25–36 and DP ≥ 37), C-type starch granules, and average chain length of the KDML105 were substantially enhanced by the open-field cultivation. Contrastingly, the relative crystallinity of RD6 starch and the amounts of short branch chains (DP 6–12 and DP 13–24), B- and A-type granules, and median granule size of KDML105 starch were significantly suppressed. Consequently, the open-field-grown RD6 starch displayed significant changes in its gelatinization and retrogradation properties, whereas, certain retrogradation parameters and peak viscosity (PV) of KDML105 starches were differentially affected by the distinct cultivating conditions. This study demonstrated the influences of production systems and soil characteristics on the physicochemical properties of rice starches. Oryza sativa L.) is one of the most essential staple crops globally [Rice , crude protein, and amylose contents), starch molecular structure , and starch physicochemical properties  have been provided. The objective of this study was thus to unravel whether the different production systems and soil characteristics could directly affect the rice productivity, grain quality, and ultimately the starch physicochemical properties of two elite Thai rice cultivars, namely, the Jasmine rice (KDML105) and the sticky rice (RD6) cultivars. Our results will establish the link between rice production systems with differing soil characteristics and their influences on yield, grain quality, and the rice grain and rice starch applications in various starchy food industries, as well as pinpoint the effective practices to improve yield and grain quality of the two elite Thai rice cultivars.Oryza sativa L.) cultivars including RD6 and KDML105 were cultivated during the 2020 crop season from 11th July to 30th November 2020 in two cultivating locations. The experiment was divided into two groups. (i) The two tested rice cultivars were cultivated in 8” plastic pots containing commercial potting soil  (one plant per pot) placed in a net house at the Faculty of Science, Khon Kaen University in Khon Kaen province, Thailand, and was called ‘net-house pot production system’. (ii) The two rice cultivars were planted in the fields of Khao Wong district in Kalasin province, Thailand, and was called ‘open-field production system’. Nine replications per cultivar for net-house pot production and open-field production were evaluated in a Randomized Complete Block Design (RCBD). In addition, Thermo-Hygrometers  were installed to monitor environmental temperature and relative humidity at 9:00 a.m. on alternate days throughout growth stages of rice plants. The average temperature and humidity were 28.73 °C and 72.32%, respectively, during the 2020 crop season (3 (LR), total nitrogen (N), available phosphorus (P), available potassium (K), cations exchange capacity (CEC), water pH, and electrical conductivity (EC) at the Center of Agricultural Commodity Standards Certification, Faculty of Agriculture, Khon Kaen University. The results are displayed in The two Thai rice  were recorded. To examine grain appearance, approximately 30 grains were randomly placed on black paper, and then an image of the rice grains was taken. Grain morphology parameters of 10 grains per plant, including grain length and width, were measured using Vernier calipers . Then, the width and length were used to calculate grain width-to-length ratio, perimeter, and volume ,49.v/v) ethanol three times. Then, 300 μL of the ethanol-soluble supernatant containing reducing sugar was dried using Speed Vac , and the residue was then reconstituted in 100 μL double-distilled water and kept at 4 °C for sugar assay. Total starch content was measured from the ethanol-insoluble pellet by digesting to glucose [Mature caryopses at the complete panicle maturity stage  were col glucose . Finally glucose . Protein glucose .w/v) sodium hydroxide at 25 °C for 3 h to completely remove grain storage protein. The suspension was stepwise filtrated through 4 layers of cheesecloth and centrifuged at 4000× g for 20 min. The pellet was washed twice with double-distilled water, and then centrifuged at 4500× g for 20 min. The top layer of proteins was removed, and the bottom starch layer was completely resuspended in 50 mL double-distilled water and neutralized by 1 M hydrochloric acid, and then centrifuged at 4500× g for 20 min. The starch was then washed twice with double-distilled water. To remove grain lipid, the starch was washed with 10 mL toluene and centrifuged at 4500× g for 20 min, and then washed with double-distilled water to completely remove the toluene residues. The white starch pellet was dried in a hot air oven  at 40 °C for 48 h [Rice starch was isolated from the sieved rice flour powder  using alfor 48 h , and grofor 48 h . Isoamylase debranching of amylopectin accompanied by measurement of amylopectin branch chain length distribution (CLD) with a high-performance anion-exchange chromatography system equipped with a pulsed amperometric detector (HPAEC-PAD) was performed according to the method modified from Tangsrianugul et al. . Each riw/v) sodium dodecyl sulfate. The starch suspension was used for size analysis at a pump speed of 2500 rpm. The results were reported as the size distribution in terms of the percent volumes (%volume) of equivalent spheres, and the starch granule size was expressed as median particle diameter (d(0.5)), which is the granule size at which 50% of all the granules by volume are smaller [Starch granule size distribution of the isolated starch was analyzed by a laser diffraction particle size analyzer . The 30 mg of isolated starch were dispersed in 1mL of 1% . Each rice starch sample was packed into a sample holder, and was scanned with an X-ray at a speed of 0.02°/s. The radiation was generated at a voltage of 45 kV and 40 mA with the scanning regions of the diffraction angle (2θ) ranging from 5° to 40°. The percentage of starch relative crystallinity was calculated following the formula .Relativg for 30 min. The supernatant was removed and transferred to a petri dish and baked in a hot air oven  at 105 °C to constant weight. The dried supernatant was then weighed to determine the rice starch solubility. Thereafter, the wet sediment was weighed for swelling power determination. The SP (g/g on a dry weight basis) and S (%) values were calculated using the following formulas:Swelling power (SP) and solubility (S) of rice starch were determined following the modified procedures of Vandeputte et al. and Wang et al. ,60. BrieTM software version 12 . To analyze the starch retrogradation properties, DSC pans containing gelatinized starches were kept at 4 ± 1 °C for 14 days. The sample pans were then rescanned at the rate of 10 °C /min from 30 to 90 °C. The transition temperatures ), peak (Tp(r)), conclusion (Tc(r)) temperatures), temperature range (∆T(r)), and the enthalpy (ΔH(r)) of melting of the retrograded structure were determined as previously mentioned. Degree of retrogradation (R) was calculated using the following equation [The sample preparation prior to analyses of gelatinization and retrogradation characteristics was carried out following the procedure modified from Tananuwong and Malila . Starch equation :R (%) = w/v) starch slurry. The slurry was stirred manually using a plastic paddle for 20 s before insertion into the RVA machine. Heating and cooling program was set as followed: equilibrated at 50 °C and mixed at 960 rpm for 10 s to allow complete dispersion, declined rotation speed to 160 rpm and holding at 50 °C for 50 s, heating to 95 °C within 3 min 42 s, and holding at 95 °C for 3 min 30 s. The slurry was finally cooled to 50 °C within 3 min 48 s, and then held at 50 °C for 2 min. The RVA pasting curve was retrieved, and the pasting temperature (PTemp), peak time (PTime), peak viscosity (PV), trough viscosity (TV), and final viscosity (FV) were recorded and used to calculate the breakdown (BD = PV − TV), and setback (SB = FV − TV). The viscosity was expressed in centipoise (cP) [Pasting properties of the rice starch were determined with a Rapid Visco Analyzer  according to the AACC International Approved Method 76–21.01 . Rice stt-test was used to evaluate the statistically significant differences (p ≤ 0.05) of the mean values between groups. Statistical analyses were performed using SPSS® statistics v.23 software  [The data were reported as mean ± standard error of the mean (SEM) of 3–4 biological replicates. The independent-samples NY, USA) .To evaluate the effect of production systems and soil characteristics on physical characteristics of RD6 and KDML105 grains, mature rice caryopses were harvested from the net-house pot and open-field production systems. The rice productivity  and grain morphology  of the two rice cultivars are presented in Production systems and soil characteristics only had a significant influence on reducing sugar content in the grains of RD6 rice cultivar , while tThe results of amylopectin fine structure of starches isolated from the two rice cultivars revealed differences in CLD of amylopectin branches between the net-house pot and open-field production systems . GeneralLaser particle-size analysis was performed to verify the influence of production systems and soil characteristics on particle size and size distribution of starch granules of both RD6 and KDML105 cultivars. The results revealed significant distinction in median particle diameters (d(0.5)) and granule size distribution of KDML105 starch between the two production systems. . AccordiThe impact of production systems and soil characteristics on the crystalline structure and relative crystallinity of RD6 and KDML105 starches were presented in The gelatinization and retrogradation behaviors of starches were characterized by the transition temperatures and the enthalpy of gelatinization and melting of the retrograded structure. The results revealed that the open-field system RD6 starch had a significantly lower gelatinization To, but greatly higher gelatinization Tc, ΔT, and ΔH compared to those of starch from the net-house pot system RD6 . On the p = 0.075) (The influence of production systems and soil characteristics on starch swelling power and solubility of RD6 and KDML105 rice cultivars were shown in = 0.075) .Temp, PTime, TV, BD, FV, and SB of RD6 and KDML105 starches , and climatic conditions play significant roles in controlling its yield and grain quality ,66,67,682+ to Fe3+, which prevented it from being taken up by the rice root [The presence of a large proportion of sand in cultivation soil is accompanied by a small amount of OM, which results in low available water capacity (AWC), cations exchange capacity (CEC), and macronutrient and micronutrient preservation of sandy soil. This typically leads to the diminutions of rice yield  ,30,72. Nice root . Fe-defiice root . Fe alsoice root . In addiice root ,75,76, bice root . The eleice root ,75, alloice root ,75. Addiice root ,78,79,80ice root ,81,82. Aice root , such coice root ,37. Thiswx gene encoding GBSSI under the low temperature [In addition to external appearance , production system and soil physical and chemical characteristics also considerably affected the grain internal quality , ultimately influencing eating and cooking quality of cooked rice grains ,26,84,85perature . Howeverindica rice cultivars grown in low N soil had small amount of amylopectin short branch chains and large amount of amylopectin long branch chains, resulting in high CL [The results of amylopectin CLD separated from the two rice starches in the net-house pot and open-field production systems showed that proportion of short A chains was in the range of 30.61% to 34.01%, which was evidently higher than their proportions of B3+ long chains (3.75–9.38%) . With th high CL .The open-field system KDML105 rice cultivar produced higher proportion of C-type starch granules in volume frequency percentage, lower proportion of B- and A-type starch granules, and a smaller median particle size of starch . It was To investigate whether production system and soil characteristics affect the physicochemical properties of starches from RD6 and KDML105 rice cultivars, their endosperm starches were analyzed for swelling power, solubility, and thermal and pasting properties. Swelling power and water solubility of rice starches display the existence of interactions between water molecules and starch chains in amorphous and crystalline domains ,60. The Interestingly, the difference in the starch gelatinization of RD6 and KDML105 between the two production systems were detected from differential scanning calorimetry (DSC), which is the thermal method for evaluating the gelatinization of starch . The disThe retrogradation properties of the starch gels upon storage at 4 °C for 14 days have been shown to associate with amylose content, the CLD and CL of amylopectin branches ,107,111.temp), peak viscosity (PV), and final viscosity (FV) but low breakdown (BD) values [In addition, rice starch which comprises low proportion of short amylopectin A chains but a high proportion of B3+ chains, displayed high pasting temperature (P) values ,112. Thi) values ,19,112. The yield, grain quality, and starch compositional, structural, and physicochemical characteristics of the two elite Thai rice cultivars were significantly influenced by the two different production systems with differing soil qualities. The presence of nutrients, especially nitrogen (N), in the soil was likely responsible for significant differences in yield, grain morphology, and starch characteristics of RD6 and KDML105 between the two production systems. The influences of the soil’s chemical characteristics on the compositional and structural features of the open-field system RD6 starch were also evident. Considerable increases were found in the gelatinization Tc, ΔT, ΔH values, therefore, the cooking of RD6 grains harvested from the open-field production system may require more time and energy. However, it could provide a similar texture to the pot-grown RD6 starch upon cooking due to its similarity in SB viscosity. Such properties could directly affect demand, acceptability, and repeat-purchasing decision of rice consumers. Moreover, the cultivation of KDML105 rice under lower soil nutrient contents in the open-field production system could substantially enhance its grain yield components, while affecting the amylopectin and starch granule molecular structure. The changes in physicochemical features of the open-field system KDML105 starch were observed in gelatinization, retrogradation, and pasting properties. However, despite considerable differences in the retrogradation transition temperatures, KDML105 grains from both systems might provide a similar sensory texture upon cooking since the SB viscosity was not distinct between the two conditions. The similar starch gel ΔH(r) and R% also suggested comparable shelf-life quality of the starchy rice foods produced from both production systems. Overall, we showed that rice grain compositional and starch behavioral responses to the soil characteristics and production systems are complex and genotypically dependent in this study.