Evaluation of ergonomic factors and postures that cause muscle pains in dentistry students’ bodies Effect of magnification loupes on dental hygiene student posture. Working postures of dentists and dental hygienists. The Effect of an Ergonomic Intervention on Musculoskeletal, Psychosocial and Visual Strain of VDT Data Entry Work: The Polish Part of the International Study Effect of magnification lenses on student operator posture. A prospective study of computer users: II. Postural risk factors for musculoskeletal symptoms and disorders. The Effect of an Ergonomic Intervention on Musculoskeletal, Psychosocial and Visual Strain of VDT Data Entry Work: The United States Part of the International Study Participatory ergonomics to reduce exposure to psychosocial and physical risk factors for low back pain and neck pain: results of a cluster randomised controlled trial Reducing musculoskeletal disorders among computer operators: comparison between ergonomics interventions at the workplace Musculoskeletal, visual and psychosocial stress in VDU operators before and after multidisciplinary ergonomic interventions. University students' notebook computer use: lessons learned using e-diaries to report musculoskeletal discomfort The Effect of an Ergonomie Intervention on Musculoskeletal, Psychosocial and Visual Strain of VDT Data Entry Work: The Norwegian Part of the International Study Effects of participatory ergonomic intervention on the development of upper extremity musculoskeletal disorders and disability in office employees using a computer Ergonomic Training Reduces Musculoskeletal Disorders among Office Workers: Results from the 6-Month Follow-Up. Evaluation of Two Preventive Interventions for Reducing Musculoskeletal Complaints in Operators of Video Display Terminals Multi dimensional system for evaluating preventive program for upper extremity disorders among computer operators. Ergonomic intervention: its effect on working posture and musculoskeletal symptoms in female biomedical scientists.
Background Work-related musculoskeletal disorders commonly experienced by dental professionals are one of the main occupational health problem affecting their health and well-being . This study was conducted to evaluate  ergonomic factors and profession-related postures  and also investigate relationship between demographic factors and work condition with pain in dental students . Material and Methods 60 freshman and sophomore dentistry students were r and omly chosen as the subjects of control group , and 60 of 5th and 6th-year students were selected as the members of exposure group . Data related to the subjects such as sex , doing exercise , severity of musculoskeletal pain were obtained through question naire . Students ’ postures were directly observed while treating patients and they were scored by REBA method . Data were analyzed by SPSS software using Man-Whitney , Kruskal-Wallis , Spearman and Kendall correlation tests . Results 80.8 % of the subjects were not aware of the correct ergonomic postures for dental procedures . Severity of musculoskeletal pain in the exposure group ( 15.9± 4.2 ) was significantly higher than the control group ( 10.5 ±3.2 ) , ( p < 0.001 ) . Risk of the most subjects ( 84 % ) was at the medium level . Students who were more involved in clinical activities experienced more muscular pains . Conclusions The musculoskeletal disorders are probable prolonged in working hours in static positions , incorrect work postures , implying more force and even tools and instruments . Therefore , students who are aware of ergonomic principals of their own profession would be able to maintain their health through activities and lifelong . Key words : Posture , dentistry , students , musculoskeletal pain The chair-side work posture of dental hygienists has long been a concern because of health-related problems potentially caused or exacerbated by poor posture . The purpose of this study was to investigate if using magnification loupes improved dental hygiene students ' posture during provision of treatment . The treatment chosen was h and -scaling , and the effect of the timing of introduction of the loupes to students was also examined . Thirty-five novice dental hygiene students took part in the study . Each student was assessed providing dental hygiene care with and without loupes , thus controlling for innate differences in natural posture . Students were r and omized into two groups . Group one used loupes in the first session and did not use them for the second session . Group two reversed this sequence . At the end of each session , all students were videotaped while performing scaling procedures . Their posture was assessed using an adapted version of Branson et al. 's Posture Assessment Instrument ( PAI ) . Four raters assessed students at three time periods for nine posture components on the PAI . A paired t-test compared scores with and without loupes for each student . Scores showed a significant improvement in posture when using loupes ( p<0.0001 ) , and these improvements were significantly more pronounced for students starting loupes immediately on entering the program compared with students who delayed until the second session ( p<0.1 ) . These results suggest a significant postural benefit is realized by requiring students to master the use of magnification loupes as early as possible within the curriculum A joint study was conducted by a manufacturer of dental stools in the Midwest of the United States and Marquette University to measure the occupational postures of dentists and dental hygienists . The postures of 10 dentists and 10 dental hygienists were assessed using work sampling and video techniques .  Postural data of the neck , shoulders and lower back were recorded from video and categorized into 30-degree intervals : o ( neutral posture of respective joint ) , 30 , 60 and 90 degrees . Each subject 's postures were observed while they were treating patients during a four-hour period , during which 100 observations of postures were recorded at r and om times . Compared to st and ing , dentists and dental hygienists were seated 78 percent and 66 percent of the time , respectively . Dentists and dental hygienists flexed their trunk at least 30 degrees more than 50 percent of the time . They flexed their neck at least 30 degrees 85 percent of the time during the four-hour duration , and their shoulders were elevated to the side of their trunk ( abducted ) at least 30 degrees more half of the time . The postures of the trunk , shoulders , and neck were primarily static . This data base of postures can be used by dental professionals and ergonomists to assess the risk dentists and dental hygienists are exposed to musculoskeletal disorders , such as low back pain or shoulder tenosynovitis , from deviated joint postures . They could use these data to select dental furniture or dental devices that promote good body posture , i.e. , reduce the magnitude and duration of deviated joint postures , which , in theory , would decrease the risk of musculoskeletal disorders A group of routine data entry operators ( female ) was included in the Polish MEPS ( musculoskeletal — eyestrain— psychosocial — stress ) study . Before the intervention , ergonomic assessment revealed improper working conditions such as inadequate lighting , uncomfortable chairs , and lack of forearm and wrist support while medical examination revealed that trapezius muscle load along with upper arm , head and back angles were higher than advisable . Subjects complained about neck and shoulder pain , visual problems , and psychosocial conditions . The ergonomic intervention included installation of new luminaires and Venetian blinds , new chairs , repair of ventilators , and optometric corrections . The results after the intervention showed mainly improvement in chair comfort , lighting conditions , visual strain , and sitting posture . However , financial limitations did not allow satisfactory completion of the intervention leading to a mixed interpretation of the results A distinct body of literature supports the association between clinical postures of the dental practitioner and work-related musculoskeletal disorders ( WRMD ) . Several aids or devices have been tested to improve clinical posture in the interest of decreasing WRMD . The use of magnification lenses while performing dental procedures may increase the quality of work and decrease the likelihood of musculoskeletal problems . To date , only anecdotal and personal opinions had existed regarding the benefits of using magnification lenses , and no empirical evidence had authenticated the contention that use of magnification lenses exerts a positive change in operator posture . The objective of this study was to assess the effect magnification lenses had on the posture of dental hygiene students . Using a r and omized crossover design , research ers videotaped nineteen senior dental hygiene students performing an intra-oral procedure with and without the use of magnification lenses . The tapes were then evaluated by a panel of five dental hygiene educators calibrated in the use of Branson 's Posture Assessment Instrument ( PAI ) . Results of a paired t-test indicate that the posture of the students while wearing magnification lenses was more acceptable ( p=.019 ) than when wearing traditional safety glasses . Results of this study indicate a quantifiable change in acceptability of posture for clinicians wearing magnification lenses  and suggest that the use of such lenses in dental education may be warranted BACKGROUND Despite widespread recommendations regarding posture during computer use , associations between specific postures and musculoskeletal health are not well characterized . METHODS Six hundred and thirty-two newly hired computer users were followed prospect ively to evaluate associations between posture and neck or shoulder ( N/S ) and h and or arm ( H/A ) musculoskeletal symptoms and musculoskeletal disorders . Participants ' postures were measured at entry and they reported symptoms on weekly diaries . Participants reporting symptoms were examined for specific disorders . Multivariate Cox regression models were used to estimate associations between postural variables and risk of symptoms and disorders , controlling for confounding variables . RESULTS Keying with an inner elbow angle > 121 degrees , greater downward head tilt , and presence of armrests on the participants chair were associated with lower risk of N/S symptoms or N/S disorders .  Keying with elbow height below the height of the " J " key and the presence of a telephone shoulder rest were associated with a greater risk of N/S symptoms or N/S disorders . Horizontal location of the " J " key > 12 cm from the edge of the desk was associated with a lower risk of H/A symptoms and H/A disorders . Use of a keyboard with the " J " key > 3.5 cm above the table surface , key activation force > 48 g , and radial wrist deviation of > 5 degrees while using a mouse was associated with a greater risk of H/A symptoms or H/A disorders . The number of hours keying/week was associated with H/A symptoms and disorders . CONCLUSIONS The results suggest that the risk of musculoskeletal symptoms and musculoskeletal disorders may be reduced by encouraging specific seated postures The United States MEPS ( musculoskeletal — eyestrain — psychosocial — stress ) study consisted of 1 group of 28 female data entry operators . The intervention was in 3 parts : workstation re design ( including advanced ergonomic chairs , motorized adjustable workstations , advanced adjustable keyboards , adjustable copyholders , adjustable footrests , monitor support surfaces ) and ergonomic training/coaching and corrective lenses . After the intervention , statistically significant reductions in physical signs ( trigger points , neck and shoulder mobility ) , subjective reports of intensity and frequency of musculoskeletal pain , and subjective reports of visual problems were observed . Static load during the work sample , as assessed by experts , improved after the intervention as did measured postural angles of head and trunk and subjective assessment of users of ergonomic characteristics of the workplaces . For all of these measures , improvements observed 1 month after intervention were also observed in the 1-year follow-up . Trapezius load , as assessed by electromyography ( EMG ) , decreased after intervention , but then increased in the follow-up . The increase was interpreted as a calibration problem Objectives This study investigated the effectiveness of the Stay@Work participatory ergonomics programme to reduce workers′ exposure to psychosocial and physical risk factors . Methods 37 departments ( n=3047 workers ) from four Dutch companies participated in this cluster r and omised controlled trial ; 19 ( n=1472 workers ) were r and omised to an intervention group ( participatory ergonomics ) and 18 ( n=1575 workers ) to a  control group ( no participatory ergonomics ) . During a 6 h meeting guided by an ergonomist , working groups devised ergonomic measures to reduce psychosocial and physical workload and implemented them within 3 months in their departments . Data on psychosocial and physical risk factors for low back pain and neck pain were collected at baseline and after 6 months . Psychosocial risk factors were measured using the Job Content Question naire and physical risk factors using the Dutch Musculoskeletal Question naire . Intervention effects were studied using multilevel analysis . Results Intervention group workers significantly increased on decision latitude ( 0.29 points ; 95 % CI 0.07 to 0.52 ) and decision authority ( 0.16 points ; 95 % CI 0.04 to 0.28 ) compared to control workers . However , exposure to awkward trunk working postures significantly increased in the intervention group ( OR 1.86 ; 95 % CI 1.15 to 3.01 ) compared to the control group . No significant differences between the intervention and control group were found for the remaining risk factors . After 6 months , loss to follow-up was 35 % in the intervention group and 29 % in the control group . Conclusion Participatory ergonomics was not effective in reducing exposure to psychosocial and physical risk factors for low back pain and neck pain among a large group of workers . Trial registration IS RCT N27472278 Typing is associated with musculoskeletal disorders ( MSDs ) caused by multiple risk factors . This control study aim ed to evaluate the efficacy of a workplace intervention for reducing  MSDs among computer workers . Sixty-six subjects with and without MSD were assigned consecutively to one of three groups : ergonomics intervention ( work site and body posture adjustments , muscle activity training and exercises ) accompanied with biofeedback training , the same ergonomics intervention without biofeedback and a control group . Evaluation of MSDs , body posture , psychosocial status , upper extremity ( UE ) kinematics and muscle surface electromyography were carried out before and after the intervention in the workplace and the motion lab . Our main hypothesis that significant differences in the reduction of MSDs will exist between subjects in the study groups and controls was confirmed ( χ2 = 13.3 ; p = 0.001 ) . Significant changes were found in UE kinematics and posture as well . Both ergonomics interventions effectively reduced MSD and improved body posture . Practitioner Summary : This study aim ed to test the efficacy of an individual workplace intervention programme among computer workers by evaluating musculoskeletal disorders ( MSDs ) , body posture , upper extremity kinematics , muscle activity and psychosocial factors were tested . The proposed ergonomics interventions effectively reduced MSDs and improved body posture The study has a parallel group design with two intervention groups ( T and S ) and one control group ( C ) of VDU operators . Three serial interventions were carried out in the T and S groups , first a new lighting system , then new workplaces and last an optometric examination and corrections if needed . The new lighting gave significantly increased illuminance levels , increased luminances of the room surfaces and better luminance distribution . The two intervention groups reported significant improvement of the lighting conditions , as well as of the visual conditions and significantly reduced visual discomfort and glare . Significant reduction of headache was found in one of the intervention groups . Optometric corrections reduced the visual discomfort in both the intervention groups . When looking at those given new corrections , a significant reduction was found in the T group and a clear tendency was also found in the S group . The C group reported no improvements for any of these health outcomes . The workplace intervention gave the operator the possibility to support the whole forearm and h and on the table top . Before the intervention there were no significant differences between the three groups regarding shoulder pain and static trapezius electromyographic ( EMG ) load . Two years after the intervention , a significant reduction of shoulder pain was reported in the T and S groups in parallel with a significant reduction in static trapezius load , while no such reduction was found in the C group . At the same time , both static trapezius load and shoulder pain were significantly lower in the T and S groups compared with the C group . Pain in the forearm and h and showed no significant changes in any of the groups during the study period . However , there seem to be a relationship between pain in the forearm and h and and the time the operator used the mouse . The C group reported significantly higher intensity of pain and used the mouse significantly more than the S group The objective of this pilot study was to identify if notebook accessories ( ergonomic chair , desktop monitor and notebook riser ) combined with a wireless keyboard , mouse and participatory ergonomics training would have the greatest impact on reducing  self-reported upper extremity musculoskeletal discomfort in university students . In addition to pre-post computing and health surveys , the Ecological Momentary Assessment was used to capture change in discomfort over time using a personal digital assistant ( PDA ) as the e-diary . The PDA was programmed with a survey containing 45 questions . Four groups of university students were r and omised to either intervention ( three external computer accessories ) or to control . Participants reported less discomfort with the ergonomic chair and notebook riser based on the pre-post survey data and the e-diary/PDA ANOVA analysis . However , the PDA data , adjusted for the effect of hours per day of computer use , showed no benefit of the chair and limited benefit from the riser . Statement of Relevance : University students ' use of notebook computers has increased . This study found evidence of a positive effect of an adjustable chair or notebook riser when combined with ergonomic training on reducing discomfort . Daily  notebook computer use of 4 h was confirmed as a risk factor . Without some form of ergonomic intervention , these students are likely to enter the workforce with poor computing habits , which places them on the road to future injuries as technology continues to play a dominant role in their lives The Norwegian MEPS ( musculoskeletal — eyestrain — psychosocial — stress ) study included 3 groups : data entry , data dialogue ( female ) and data dialogue  ( male ) . Before intervention , the data entry group reported significantly more symptoms and signs of musculoskeletal illness and had longer periods in front of the video display terminal ( VDT ) without a break . The ergonomic intervention consisted mainly of ergonomic information and training . After intervention , the data dialogue female group reported a significant reduction in shoulder pain in parallel with a reduction in trapezius load . Increasing the underst and ing in how to adjust the work st and and chair may have been contributing factors to reducing the pain level . There was a significant reduction in eye problems in all groups ; the greatest reduction in eye symptoms was seen in the groups who had new optometric corrections Objective : To evaluate the participatory ergonomic method on the development of upper extremity musculoskeletal disorders and disability in office employees . Methods : This study is a r and omized controlled intervention study . It comprised 116 office workers using computers . Those in the intervention group were taught office ergonomics and the risk assessment method . Cox proportional hazards model and generalized estimating equations ( GEEs ) were used . Results : In the 10-month postintervention follow-up , the possibility of developing symptoms was 50.9 % . According to multivariate analysis results , the possibility of developing symptoms on the right side of the neck and in the right wrist and h and was significantly less in the intervention group than in the control group ( p<0.05 ) . Neck disability/symptom scores over time were significantly lower in the intervention group compared with the control group ( p<0.05 ) . Conclusion : The participatory ergonomic intervention decreases the possibility of musculoskeletal complaints and disability/symptom level in office workers BACKGROUND Musculoskeletal disorders are commonly reported among computer users . This study explored whether these disorders can be reduced by the provision of ergonomics education . METHODS A cluster r and omised controlled trial was conducted in which 3 units were r and omised for intervention and received training , and 3  units  were given a leaflet . The effect of intervention on workstation habits , musculoskeletal disorders , days and episodes of sick leave , and psychological well-being were assessed . RESULTS A significant improvement in workstation habits was found , and the differences remained significant at the follow-up time point for keyboard , mouse , chair , and desk use . The largest reduction in the percentage of musculoskeletal disorders was in the neck region ( -42.2 % , 95 % CI -60.0 to -24.4 ) . After adjusting for baseline values , significant differences were found at the follow-up time point in the neck , right shoulder , right and left upper limbs , lower back , and right and left lower limbs . No significant differences were found for the days and episodes of sick leave or the psychological well-being among workers after the intervention . CONCLUSION Consistent reductions were observed for all musculoskeletal disorders at the follow-up time point , although the difference was not statistically significant for the upper back . The improvements in the musculoskeletal disorders did not translate into fewer days lost from work or improved psychological well-being Background and Purpose The purpose of this study was to evaluate the efficacy of a preventive ergonomic intervention , which was provided by physical therapists , on spinal and upper-extremity work-related posture and symptom complaints of workers who use video display terminals ( VDT ) . Subjects Two hundred employees who spent at least 20 hours per week at a VDT were r and omly divided into 2 groups . Group E received the ergonomic intervention and an informative brochure , and group I received only the brochure . Methods Both groups were evaluated at the beginning of the study and at a follow-up 5 months later . The following tools were used : a pain drawing and the Rapid Entire Body Assessment ( REBA ) method to assess spinal and upper-extremity work-related posture . Results Group E had a lower REBA score and reduced lower back , neck , and shoulder symptoms compared with group I. Discussion and Conclusion The results suggest that a personalized preventive ergonomic intervention can improve spinal and upper-extremity work-related posture and musculoskeletal symptoms for workers who use VDTs Typing is associated with musculoskeletal complaints ( MSCs ) , caused by multiple risk factors . Although a wide variety of ergonomic intervention programs were conducted to reduce risk factors and MSC 's , only few of them were found evidence based . This study aim ed to test the efficacy of a workplace intervention in reducing MSC 's among computer workers . 66 computer workers were assigned r and omly to one of three intervention programs : ergonomic intervention including biofeedback , intervention without biofeedback and control group without intervention . The efficacy was tested by advanced assessment including ; pain location and severity , posture at work , upper extremity 3D kinematics , muscle activity and psychosocial status . Working hypothesis ; significant score differences will be found between the study groups which underwent ergonomic intervention and the control group on the following measures : pain complaints , upper extremity kinematics , muscle activity and psychosocial status . Significant differences were found between pre and post intervention and between research groups and the control group in pain , posture and motion . The ergonomic intervention with biofeedback had no unique contribution in comparison to other interventions . In conclusion ; the proposed intervention program was found efficient for reducing pain among computer workers This study investigates the effect of ergonomic intervention on working posture and musculoskeletal symptoms in female biomedical scientists . The Nordic musculoskeletal question naire ( NMQ ) , body discomfort chart ( BDC ) and rapid upper-limb assessment ( RULA ) are the tools for assessment . The study was conducted in three phases : pre-intervention , intervention and post-intervention . Pre-intervention , 79 % of subjects reported a three-month prevalence of symptoms , and these were reported more frequently by those working in haematology/transfusion . Analysis by RULA showed that the majority ( 59 % ) of postures had a gr and score of four . A further 24 % had scores of five or six . The highest frequency of poor postures was seen in haematology/transfusion . Intervention comprised physical workplace changes , a seminar , and advice on risk factors . In the post-intervention phase , baseline measurements were repeated . Reporting of three-month prevalence of symptoms had decreased to 54 % , and reports of body discomfort also had decreased . The majority ( 64 % ) had a RULA gr and score of three . No observed postures had scores of five or six . In conclusion , ergonomic intervention result ed in an improvement in working postures , and a decrease in the prevalence of musculoskeletal symptoms and body discomfort . Analysis of findings indicate that RULA scores generally corresponded with reporting of symptoms ( NMQ ) and discomfort ( BDC )
CONCLUSIONS Based on a limited number of studies , the use of ergonomic saddle seats and dental loupes leads to improved working postures .
The use of loupes appears to relieve shoulder , arm and h and pain .
However , their effect on neck pain is scarce .
None of the studies reported on the effect of the saddle seats on musculoskeletal pain .
OBJECTIVES Musculoskeletal disorders affect a high percentage of dentists , dental hygienists and therapists .
Static and awkward working postures are considered as major risk factors .
Proper seat selection and use of magnification loupes are promoted for their ergonomic benefits .
The aim of this review was to evaluate the existing empirical evidence on the effect of the above interventions on ( i ) correction of poor posture and ( ii ) reduction in musculoskeletal pain .