Guided tissue regeneration in the treatment of human infrabony defects. Clinical, radiographical and microbiological results: a pilot study. GTR with bioresorbable membranes in the treatment of intrabony defects: a clinical and histologic study. Treatment of interproximal angular defects by guided tissue regeneration: 1 year follow-up. Long-term results of guided tissue regeneration therapy with non-resorbable and bioabsorbable barriers. III. Class II furcations after 10 years. Treatment of intrabony defects with enamel matrix proteins or bioabsorbable membranes. A 4-year follow-up split-mouth study. Comparison of clinical, radiographic, and histometric measurements following treatment with guided tissue regeneration or enamel matrix proteins in human periodontal defects. Long-term results of guided tissue regeneration therapy with non-resorbable and bioabsorbable barriers. I. Class II furcations. Factors affecting the healing response of intrabony defects following guided tissue regeneration and access flap surgery. Efficacy of guided tissue regeneration in the management of through-and-through lesions following surgical endodontics: a preliminary study. Enamel matrix proteins and guided tissue regeneration with titanium-reinforced expanded polytetrafluoroethylene membranes in the treatment of infrabony defects: a comparative controlled clinical trial. Assessment of guided tissue regeneration procedures in intrabony defects with bioabsorbable and non-resorbable barriers. Healing of human intrabony defects following treatment with enamel matrix proteins or guided tissue regeneration. Comparison of treatments of infrabony defects with enamel matrix derivative, guided tissue regeneration with a nonresorbable membrane and Widman modified flap. A pilot study. Topical and systemic antimicrobial therapy in guided tissue regeneration. Healing response of apicomarginal defects to two guided tissue regeneration techniques in periradicular surgery: a double-blind, randomized-clinical trial. Periodontal regeneration of human intrabony defects with bioresorbable membranes. A controlled clinical trial. Efficacy of xenogeneic bone grafting with guided tissue regeneration in the management of bone defects after surgical endodontics.
The aim of the study was to evaluate the clinical , radiographical and microbiological outcome after using guided tissue regeneration ( GTR ) with a bioabsorbable membrane , Resolut . Subjects with bilateral infrabony defects at single rooted teeth were selected . A total of 22 teeth , 2 in each 1 of 7 patients and 4 in 2 patients , with probing pocket depth > or = 5 mm , 3 months after scaling , participated . At baseline , assessment s of plaque and gingival indices , bleeding on probing , probing pocket depth and probing attachment level were recorded and reproducible radiographs for computer-based bone level measurements were taken . Bacterial sample s were collected to investigate the presence of periodontitis-associated bacteria , e.g. , Porphyromonas/Prevotella- and Fusobactrium-like micro-organisms . One tooth was r and omly treated with GTR and the contralateral with an open debridement procedure as a control . Clinical , radiographical and microbiological examinations were repeated 6 and 12 months postoperatively . Both procedures demonstrated a statistically significant improvement of gingival conditions , reduction of pocket depths and gain of attachment . When evaluating the differences between test and control teeth , none of the clinical parameters yielded statistical difference . Computer-based bone-level measurements showed only small differences in the majority of both test and control sites . The differences were not significant . Periodontitis-associated bacteria were present at baseline , but the appearance was not related to any specific site or patient and did not demonstrate any unwanted change in the 6- and 12-month sample s. The findings suggest that the clinical , radiographical and microbiological improvements were not significantly enhanced with the GTR therapy The aim of the present study was to evaluate clinical ly and histologically the treatment of intrabony periodontal defects with a bioresorbable membrane barrier .  Fifty-two intrabony periodontal defects were treated according to the principles of guided tissue regeneration ( GTR ) with a bioresorbable membrane . Results were evaluated by assessing probing pocket depth , recession of the gingival margin , and clinical attachment level at baseline and at 1 and 2 years after therapy . Bone level changes were evaluated radiographically . The postoperative phase was uneventful in all cases . There was a mean probing pocket depth reduction from 8.4 to 3.6 mm , a mean increase of gingival margin recession from 1.5 to 3.0 mm , and a mean clinical attachment level change from 9.9 to 6.5 mm . Mean attachment gain was 3.4 mm . Two teeth scheduled for extraction were also treated with the same bioresorbable membrane . The histologic analysis 6 months after treatment revealed the formation of new connective tissue attachment and new alveolar bone in both cases . Based on the histologic findings it can be concluded that the clinical improvements following GTR with this type of bioresorbable membrane may represent , at least in part , true periodontal regeneration The periodontal regeneration of interproximal bone defects of the posterior teeth produced by guided tissue regeneration ( GTR ) , with exp and ed Polytetrafluoroethylene barrier membranes and conventional therapy , was clinical ly evaluated in 20 intrabony periodontal defects in 10 patients . The material included the presence of at least two proximal angular lesions for the same patient , probing pocket depth > or = 6 mm , bone defect depth > or = 3 mm , and 2-wall defects with crestal involvement relative to the tooth circumference ranging from 90 to 270 degrees . Healing was clinical ly evaluated by surgical re-entry of GTR-treated sites ( 10 sites ) and debridement only sites ( 10 sites ) 1 year after initial surgery following a strict plaque control regimen . A significant correlation was observed between probing depth reduction , attachment gain and defect depth ( test sites ) ; there was increased bone fill in GTR-treated lesions of 2.95 + /- 1.3 mm corresponding to a 69.4 % improvement compared to control sites , and 1.3 + /- 1.0 mm corresponding to a 32 % improvement ( P < 0.0039 ) . The results demonstrated that bone regeneration is highly reliable , as compared to conventional therapy , in cases of severe periodontal bone loss from posterior teeth provided that the principles of GTR are applied BACKGROUND The aim of this 10-year follow-up was to evaluate the long-term results after guided tissue regeneration ( GTR ) therapy of Class II furcation defects using non-resorbable and bioabsorbable barriers clinical ly . METHODS In nine patients with advanced periodontitis , nine pairs of contralateral Class II furcation defects were treated . Within each patient , one defect received a non-resorbable exp and ed polytetrafluoroethylene barrier ( ePTFE ; C ) and the other a bioabsorbable ( polyglactin 910 ; T ) barrier by r and om assignment . At baseline and 12 and 120 + /- 6 months after surgery , clinical parameters were obtained . RESULTS Twelve and 120 months after GTR therapy , statistically significant ( P < 0.05 ) horizontal clinical attachment level ( CAL-H ) gain was observed in both groups ( C12 : 1.9 + /- 0.5 mm ; C120 : 1.1 + /- 1.3 mm ; T12 : 1.9 + /- 0.8 mm ; T120 : 1.7 + /- 1.4 mm ) . However , one patient with furcations that had been assessed as Class I 12 months after GTR therapy had lost two teeth after 10 years , and another patient had lost more than 2 mm CAL-H at one furcation from 12 to 120 + /- 6 months post-surgery 10 years after implantation of an ePTFE barrier . Horizontal bone sounding revealed similar bone gain in both groups 120 + /- 6 months post-surgery ( C120 : 0.8 + /- 1.0 mm ; T120 : 1.1 + /- 1.1 mm ) . CONCLUSIONS CAL-H gain achieved after GTR therapy in Class II furcations was stable after 10 years in 15 of 18 defects ( 83 % ) . The study failed to show a statistically significant difference in stability of CAL-H gain between group C and T 10 years after GTR therapy BACKGROUND Treatment with enamel matrix proteins ( EMD ) and guided tissue regeneration ( GTR ) with bioabsorbable membranes has been shown to promote periodontal regeneration ; however , until now , there were only limited data on the long-term clinical results following these regenerative techniques . Therefore , the aim of the present study was to present the 4-year results following treatment of intrabony defects with EMD or guided tissue regeneration ( GTR ) . METHODS Twelve patients , each displaying one pair of intrabony defects located contralaterally in the same jaw , were r and omly treated with EMD or with GTR by means of bioabsorbable membranes . The following clinical parameters were evaluated at baseline , at 1 year , and at 4 years after treatment : plaque index ( P1 ) , gingival index ( G1 ) , bleeding on probing ( BOP ) , probing depth ( PD ) , gingival recession ( GR ) , and clinical attachment level ( CAL ) . The primary outcome variable was CAL . No statistically significant differences between the groups were found at baseline . Power analysis to determine superiority of EMD treatment showed that the available sample size would yield 70 % power to detect a 1 mm difference . RESULTS The sites treated with EMD demonstrated mean CAL change from 9.8 + /- 2.0 mm to 6.4 + /- 1.6 mm ( P<0.001 ) and to 6.8 + /- 1.8 mm ( P<0.001 ) at 1 and 4 years , respectively . No statistically significant differences were found between the CAL mean at 1 and 4 years postoperatively . The sites treated with GTR showed a mean CAL change from 9.8 + /- 2.3 mm to 6.6 + /- 1.7 mm ( P<0.001 ) at 1 year and to 6.9 + /- 1.8 mm ( P<0.001 ) at 4 years . The CAL change between I and 4 years did not present statistically significant differences . No statistically significant differences in any of the investigated parameters were observed at 1 and 4 years between the treatment groups . CONCLUSIONS It was concluded that the CAL gain obtained following treatment with EMD or GTR can be maintained over a 4-year period BACKGROUND The purpose of this study was to compare the clinical and radiographic parameters with the histometric findings following 2 different regenerative procedures in humans . METHODS Fourteen advanced intrabony defects at teeth scheduled for extraction were r and omly treated as follows : 8 with guided tissue regeneration ( GTR ) using bioabsorbable barriers and 6 with an enamel matrix protein derivative ( EMD ) .  St and ardized radiographs , probing depths ( PD ) , and attachment levels ( CAL ) at baseline and 6 months after therapy were evaluated and compared to the histometric measurements made following the removal of teeth and surrounding tissues 6 months after the surgery . RESULTS Significant PD reductions ( GTR : -5.62 mm ; EMD : -5.00 mm ) and CAL gains ( GTR : 3.87 mm ; EMD : 2.67 mm ) were observed in both groups . Six months after surgery , minor resorptions of the alveolar crest ( AC ) ( GTR : 0.40 mm ; EMD : 0.33 mm ) and bony gain at the bottom of the defects ( GTR : 0.47 mm ; EMD : 1.05 mm ) were observed radiographically . No statistically significant differences in the change of clinical and radiographic parameters between the GTR and EMD groups were found . Histometrically , significant amounts of new connective tissue attachment ( i.e. , cementum with inserting collagen fibers ) were observed in both groups ( GTR : 2.29 mm ; EMD : 1.81 mm ) . Bone regeneration was found to be significant only in the GTR group ( GTR : 1.93 mm ; EMD : 0.78 mm ) . However , the study lacked statistical power for determining equivalence between the groups . CONCLUSIONS Within the limitations of the present study , it may be concluded that at 6 months after GTR or enamel matrix protein derivative therapy , formation of new cementum and bone may be histometrically demonstrated . Except for the formation of new bone , no statistically significant differences between both therapies could be seen for clinical , radiographic , and histometric results 6 months after surgery BACKGROUND The aim of this 5-year follow-up study was to clinical ly and radiographically evaluate the long-term results after guided tissue regeneration ( GTR ) therapy of Class II furcation defects using non-resorbable and bioabsorbable barriers . METHODS Nine pairs of contralateral Class II furcation defects were treated in 9 patients with advanced periodontitis . Within each patient , one defect received a non-resorbable ( exp and ed polytetrafluoroethylene [ ePTFE ] ; control , C ) barrier and the other a bioabsorbable ( polyglactin 910 ; test , T ) barrier by r and om assignment . At baseline , 6 , and 60 + /- 3 months after surgery , clinical parameters and st and ardized radiographs were obtained . Gain of bone density within furcation areas was assessed using subtraction radiography . RESULTS Six and 60 months after GTR therapy , statistically significant ( P < 0.05 ) horizontal attachment ( CAL-H ) gain was observed in both groups ( C6 : 1.7 + /- 0.8 mm ; C60 : 1.6 + /- 1.2 mm ; T6 : 2.0 + /- 0.7 mm ; T60 : 2.2 + /- 0.9 mm ) . However , 1 furcation assessed as Class I six months after GTR therapy with a bioabsorbable barrier had progressed to Class III after 5 years , and in another patient , 5 years after placement of an ePTFE barrier , 1 furcation had lost all the CAL-H gain that had been observed at 6 months . Subtraction analysis revealed similar area gain in both groups 6 and 60 months postsurgically ( C6 : 0.3 + /- 0.5 ; C60 1.0 + /- 1.7 ; T6 : 0.4 + /- 0.4 ; T60 : 1.1 + /- 1.7 ) . CONCLUSIONS CAL-H gain achieved after GTR therapy in Class II furcations was stable after 5 years in 16 of 18 defects . The study failed to show a statistically significant difference in stability of CAL-H gain between control and test groups 5 years after GTR therapy Identification and control of significant factors determining clinical outcomes is of paramount importance to improve expected results of a variety of therapeutic procedures . The aim of this investigation was to identify , with a multivariate approach , factors associated with healing outcomes of 3 periodontal surgical procedures in deep intrabony defects . 45 patients with evidence of deep intrabony defects were r and omly assigned to 3 treatment groups : access flap ( group C ) , conventional guided tissue regeneration ( GTR ) with non-resorbable exp and ed polytetrafluoroethilene ( ePTFE ) membranes ( group B ) , and GTR with self supporting membranes combined with the modified papilla preservation technique ( group A ) . In both GTR procedures , membranes were positioned coronal to the interproxymal alveolar crest . Primary outcome variables ( i.e. , probing attachment level gains at 1 year and the amount of newly formed tissue present at membrane removal ) were explained in terms of a series of patient , defect morphology and surgical factors , using a multivariate approach . Highly significant treatment effects were observed , indicating that the 3 tested therapeutic modalities result ed in significant differences in primary outcome variables . Detailed analysis assessing the significance of the tested factors in determining the healing outcomes following each procedure was performed with a stepwise elimination approach of non-significant factors . The results indicated that : ( i ) the need to create and maintain space should be a key objective of regenerative approaches based upon the principles of guided tissue regeneration ; ( ii ) control of patient 's oral hygiene and residual periodontal infection in the oral cavity are strongly associated with clinical outcomes of both regenerative and conventional surgical procedures and should receive proper attention The purpose of this prospect i ve study was to assess the outcome of periradicular surgery with or without guided tissue regeneration ( GTR ) for the treatment of through- and -through lesions . Thirty-four teeth were included according to specific selection criteria . In the test group ( using GTR ) , after root-end filling , the defects were filled with anorganic bovine bone and covered with a resorbable collagen membrane .  Healing was assessed according to specific criteria and grade d as successful , doubtful , or failed . In the control group , neither grafts nor membranes were used . After 1 year , 31 teeth were evaluated . Of these , 22 ( 71 % ) healed successfully , 6 ( 19 % ) showed doubtful healing , and 2 were recorded as failures . The outcomes of the defects treated with  GTR  ( 88 % successful ) were significantly better than those of the control group ( 57 % successful ) . The present study showed that the use of GTR associated with anorganic bovine bone in the treatment of through- and -through lesions may positively affect the healing process BACKGROUND Several studies have documented the clinical efficacy of guided tissue regeneration ( GTR ) with non-resorbable exp and ed polytetrafluoroethylene ( ePTFE ) membranes and enamel matrix proteins ( EMP ) in the treatment of infrabony defects . The objective of this controlled clinical study was to compare the clinical outcomes of 3 surgical modalities in the treatment of deep interproximal infrabony defects . METHODS Ninety ( 90 ) defects in 90 healthy subjects affected by chronic periodontitis were assigned to 1 of 3 treatment groups by blocking to prognostic variables . The test group was treated with the application of EMP and the simplified papilla preservation ( SPP ) technique ; the second group was treated with titanium-reinforced ePFTE membranes and the SPP technique ; and the third group was treated with the SPP technique used as access flap control procedure . No differences were observed in terms of baseline oral hygiene and defect characteristics among the 3 groups , indicating that the blocking approach was effective . A stringent infection control program was adopted for 1 year . RESULTS The 1-year results indicated that : 1 ) all treatment modalities result ed in clinical ly significant improvements in clinical attachment levels ( CAL ) and reduction in probing depth ( PD ) ; 2 ) a statistically significant treatment effect was demonstrated comparing the EMP test , the membrane control , and the flap control groups in terms of CAL gains ; 3 ) both the EMP test and the membrane control groups showed significant CAL gains compared to the flap control group ; 4 ) a statistically significantly greater amount of CAL gain was demonstrated in GTR-treated compared to EMP-treated patients ; 5 ) deeper residual probing depths but smaller increases in gingival recession were demonstrated following EMP therapy ; and 6 ) smoking habits reduced the clinical outcomes of both regenerative procedures . CONCLUSIONS The use of a regenerative procedure is indicated in the treatment of deep vertical bony defects since both the regenerative techniques ( GTR and EMD ) in the present study result ed in clinical ly and statistically significant improvements in clinical parameters compared to the access flap procedure . The use of EMP can be helpful in esthetically-sensitive sites and in reducing patient morbidity THE PURPOSE OF THIS STUDY was to assess periodontal regenerative techniques in intrabony defects utilizing a bioabsorbable , polylactic acid ( PLA ) barrier or the non-resorbable , exp and ed polytetrafluoroethylene ( ePTFE ) barrier .  Thirty patients ( 26 to 64 years old ) each with one radiographically evident intrabony periodontal lesion of probing depth > or = 6 mm participated in a 12-month controlled clinical trial . The subjects were r and omly divided into two independent groups . The test group ( n = 16 ) received a PLA barrier . The control group ( n = 14 ) received an ePTFE barrier .  Plaque index ( PI ) , gingival index ( GI ) , probing depth ( PD ) , clinical attachment level ( CAL ) , and bone fill were recorded by a single calibrated examiner not involved with the surgical treatment prior to surgery , and at 6 , 9 , and 12 months postsurgery . The treatment results were statistically analyzed utilizing two sets of data . The " averaged-site " data set consisted of values computed from the averaging of measurements from all sites encompassing the defect . The second data set was comprised of only the deepest measurement of the defect . Statistical tests used to analyze these data sets included the t-test and paired t-test for parametric data and the Wilcoxon rank sum test and the Wilcoxon signed rank test for non-parametric data . Analyses with both the averaged-site data and deepest-site data result ed in significant improvements in PD reductions , CAL , and bone fill , after 12 months of healing with both the PLA and ePTFE barrier devices . Comparisons of healing response between treatments found no significant differences when the averaged-site data were analyzed . When only the deepest site of the defect was considered , the control group result ed in significantly more attachment gain ( ePTFE , 3.36 mm ; PLA , 1.75 mm ; P < 0.02 ) and shallower probing depths ( ePTFE , 3.29 mm ; PLA , 4.69 mm ; P < 0.01 ) than the test group . In intrabony defects , the use of PLA or ePTFE barriers in GTR procedures yielded comparable clinical results ; however , in this study , data analysis using the deepest site of the defect found , after 12 months of healing , significantly more attachment gain and shallower probing depths with ePTFE The aim of the present study was to evaluate histologically in humans the healing of advanced intrabony defects following treatment with enamel matrix proteins ( EMD ) or guided tissue regeneration ( GTR ) .  Fourteen patients , each of them displaying 1 advanced intrabony defect around teeth scheduled for extraction were included in the study . The defects were treated r and omly either with an enamel matrix protein derivative ( Emdogain , BIORA AB , Malmö , Sweden ) or with a bioabsorbable membrane ( Resolut , Regenerative Material , W.L. Gore & Assoc . , Flagstaff , Arizona , USA ) . At baseline the mean probing pocket depth ( PPD ) in the EMD group was 11.3 + /- 1.8 mm and the mean clinical attachment level ( CAL ) 12.1 + /- 2.0 mm , whereas in the GTR group the mean PPD was 11.4 + /- 2.2 mm and the mean CAL 13.3 + /- 2.3 mm . Healing was uneventful in all cases . Neither allergic reactions against EMD or the bioabsorbable membrane , nor suppuration or abscesses were observed . The clinical results revealed at 6 months in the EMD group a mean PPD of 5.6 + /- 1.3 mm and a mean CAL of 9.1 + /- 1.5 mm . In the GTR group the mean PPD was 5.6 + /- 1.3 mm and the mean CAL 10.1 + /- 1.5 mm . The histological analysis showed in the EMD group a mean 2.6 + /- 1.0 mm of new attachment ( i.e. new cementum with inserting collagen fibers ) and a mean 0.9 + /- 1.0 mm of new bone . In this group , the formation of new attachment was not always followed by bone regeneration . In the GTR group , the mean new attachment was 2.4 + /- 1.0 mm and the mean new bone 2.1 + /- 1.0 mm . In every case treated with GTR , the formation of new attachment was followed by a varying amount of new bone . After both types of regenerative treatment the newly formed cementum displayed a predominantly cellular character . The findings of the present study indicate that the treatment of intrabony defects with enamel matrix proteins or with bioabsorbable membranes enhances the formation of a new connective tissue attachment in humans BACKGROUND , AIMS The purpose of the present study was to compare the efficacy of 3 different surgical procedures in the treatment of infrabony defects :  guided tissue regeneration ( GTR ) with non-resorbable membranes , Widman modified flap ( WMF ) and enamel matrix derivative ( EMD ) . METHOD 30 patients with an infrabony component > or = 4 mm were selected . 10 were treated with exp and ed polytetrafluorethylene ( ePTFE ( Gore - Tex W. L. Gore and Associates , Flagstaff , AZ , USA ) ) membranes , 10 with WMF and 10 with enamel matrix derivatives ( Emdogain ( U Biora AB Malm , Sweden ) ) . The efficacy of each treatment modality was investigated through regression analysis . Probing attachment level ( PAL ) gain , probing depth ( PD ) reduction and gingival recession ( REC ) variation were analyzed . RESULTS Both Emdogain ( enamel matrix derivative ) and ePTFE treatment show significant better results as compared to the WMF procedure in which there were no significant changes in PAL gain and PD reduction at baseline and 1 year after surgery . CONCLUSIONS Results from our analysis suggest that there is no statistically significant difference in PAL gain between GTR and EMD . The clinical outcomes of this pilot study may be of little significance , considering the small number of patients , but it has provided an important base for a controlled clinical trial ( with a larger number of patients ) which is currently in progress BACKGROUND Bacterial contamination of membrane material negatively affects healing after guided tissue regeneration ( GTR ) procedures ; conversely , flap connective tissue integration on barrier material improves the clinical outcomes . The objective of this study was to evaluate the effect of topical application of antibiotics on : 1 ) clinical outcomes of  GTR surgical procedures using titanium reinforced exp and ed polytetrafluoroethylene ( ePTFE ) periodontal membrane ; 2 ) bacterial colonization of membrane material ; and 3 ) flap connective tissue-membrane integration . METHODS Fifty-six deep interproximal bony defects were treated with  GTR surgical procedures  using titanium reinforced ePTFE periodontal membranes . Patients were r and omly assigned to 1 of the 2 antimicrobial treatment groups : the test group received weekly topical application of 25 % metronidazole gel and the control group received systemic antibiotics ( amoxicillin plus clavulanic acid 1 g/day for 14 days ) . Clinical outcomes were assessed at 1 year ; the amount of bacterial contamination and connective tissue integration on membrane material was evaluated at time of membrane removal by means of a morphological ( SEM ) method . RESULTS No statistically significant difference was found between test and control groups in terms of clinical attachment ( CAL ) gain ( baseline CAL - 12 months CAL ; P = 0.2 ) and probing depth ( PD ) reduction ( baseline PD - 12 months PD ; P = 0.6 ) . A greater increase in gingival recession ( REC ) ( 12 months REC - baseline REC ) was found in the test group compared to the control group ( P = 0.003 ) . The SEM analysis revealed no statistically significant ( t test ) difference between test and control groups in the number of fields positive to integrated connective tissue ( P = 0.82 ) , while the number of fields positive to bacteria was statistically higher ( P < 0.001 ) in the control group . CONCLUSIONS Local antibiotic administration is more effective than systemic use in preventing membrane contamination , but it does not improve clinical outcomes due to an interference of the vehicle ( gel ) with gingival tissues which may reduce the potential benefits derived from better control of the bacterial load AIM To compare healing responses to periosteal sliding grafts and polyglactin 910 periodontal mesh used as guided tissue regeneration ( GTR ) material s/techniques when both periapical and periradicular bone loss are present . METHODOLOGY Thirty patients with suppurative chronic apical periodontitis with apicomarginal communication were selected and allocated r and omly into two groups according to the barrier technique to be used during periradicular surgery : periosteal graft group ( n = 15 ) and bioabsorbable membrane group ( n = 15 ) . Clinical and radiological evaluations were completed prior to surgery , a week later and every 3 months after surgery up to 12 months to measure the periodontal pocket depth ( PD ) , clinical attachment level ( CAL ) , gingival margin position ( GMP ) , size of periapical lesion , percentage reduction of the periapical rarefaction , and periapical healing . RESULTS Both groups showed highly significant ( P < 0.001 ) reductions in periodontal PD , CAL and size of periapical lesion at 12 months whilst GMP was unaltered . No significant difference between the experimental groups was evident for these parameters , or for the percentage reduction of size of the periapical lesion and clinical -radiographic healing . CONCLUSION Guided tissue regeneration applied to apicomarginal defects using sliding periosteal grafts and use of bioabsorbable membranes led to similar enhancements of the clinical outcome of periradicular surgery in terms of periapical healing , gain of periodontal support , PD reduction and minimal recession of the gingival margin The purpose of this controlled clinical trial was to compare the clinical efficacy of 3 treatment modalities in the treatment of deep interproximal intrabony defects . Thirty-six ( 36 ) defects in 36 patients were r and omly assigned to 1 of 3 treatment groups by blocking to prognostic variables . The test was treated with bioresorbable membranes positioned coronal to the interproximal bone crest ; the second group ( membrane control ) was treated with conventional non-resorbable ( ePTFE ) barrier membranes applied coronal to the alveolar crest ; the third group ( flap Control ) was treated with an access flap procedure ( MWF ) . No differences were observed in terms of baseline oral hygiene and defect characteristics among the 3 groups , indicating that the blocking approach was effective . A stringent infection control program was enforced for 1 year . The results indicated that : 1 ) at 1 year all treatment modalities result ed in clinical ly significant improvements in clinical attachment levels ( CAL ) and reductions in probing depths ; 2 ) a statistically significant treatment effect ( P < 0.0001 , ANOVA ) was observed comparing the test ( 4.6 + /- 1.2 mm ) , the membrane control ( 5.2 + /- 1.4 mm ) , and the flap control groups ( 2.3 + /- 0.8 mm ) in terms of CAL gain ; 3 ) differences in terms of CAL gain between the test ( bioresorbable ) and the membrane control ( ePTFE ) groups were not statistically significant ( P = 0.19 , t-test ) ; 4 ) both the test and the membrane control groups gained significantly more CAL at 1 year than the MWF group ( P < 0.0001 , t-test ) . CAL gains > or = 4 mm were observed in 83.3 % of cases in both GTR groups , while CAL gains of this magnitude were not detected in the MWF group . We concluded that clinical ly significant CAL gains can be obtained with GTR procedures using both bioresorbable and non-resorbable membranes . Patients ' morbidity , however , was lower in the group treated with bioresorbable membranes PURPOSE The purpose of this prospect i ve clinical trial was to monitor the outcomes of periradicular surgery in large periapical lesions with or without guided tissue regeneration ( GTR ) and anorganic bovine bone . MATERIAL S AND METHODS All teeth in the study revealed a periradicular lesion measuring at least 10 mm . A total of 63 teeth in 44 patients were included according to specific selection criteria . In the test group , after root end filling was completed , the defect was filled with anorganic bovine bone and was covered with a resorbable collagen membrane . In the control group , neither graft nor membrane was used . RESULTS A total of 59 teeth in 41 patients were evaluable at 1-year follow-up . Of these , 24 teeth belonged to the test group and 35 to the control group . Overall , 46 teeth ( 78 % ) had successfully healed , 10 ( 16.9 % ) demonstrated uncertain healing , and 3 exhibited treatment failure . Investigators found no statistically significant differences in outcome between test and control groups . CONCLUSIONS The present study showed that the use of GTR in association with anorganic bovine bone in the treatment of patients with large periradicular lesions of strictly endodontic origin has no beneficial effect on outcome
In most respects , all membranes and enamel matrix derivative ( EMD ) delivered better outcomes , in the range of 1 to 2 mm , than open flap debridement .
The use of any barrier type or EMD configuration was found to yield more Clinical Attachment Level ( CAL ) gain than any open flap configuration .
GTR was confirmed to be superior to open flap debridement
In a 1998 review article , Laurell and colleagues performed a meta- analysis of relevant guided tissue regeneration ( GTR ) articles over the previous 20 years ( 1 ) .
The purpose of the present research was to exp and on that work , particularly search ing for trends discriminating between bioabsorbable and non-bioabsorbable barriers , as well as the use of enamel matrix derivative , with respect to interproximal bony defects .