OBJECTIVE: This study aims to determine the prevalence of musculoskeletal disorders among dentists, explore the risk factors and identify the ergonomic preventive measures for dental professionals.
METHODS: Articles published between 2008-2020 were searched in scientific databases (MEDLINE, PubMed, Scopus and Cochrane Library). The Critical Appraisal Skills Programme Systematic Review Checklist was used to assess the quality of the studies.
RESULTS: Eighteen studies were found to be suitable in the final review. Relevant data was extracted and summarized from the included studies. The annual prevalence of musculoskeletal disorders in any body site ranged between 68% and 100%. The most predominant regions for musculoskeletal disorders among dental professionals were identified to be the lower back (29% to 94.6%), shoulder (25% to 92.7%), and neck (26% to 92%). The most frequently reported risk factors of MSDs were the individual characteristic female gender (57.1%), followed by awkward working postures (50%), long working experience (50%) and being dental specialists (42.9%). Several preventive measures were identified as the most effective ways in preventing MSDs, the use of magnification (40%) and regular physical activity (40%).
CONCLUSIONS: This review reported a high prevalence of musculoskeletal disorders (MSD) among dentists. It critically updates and adds the latest evidence on occupational ergonomics among dentists.
METHODS: Data were collected between 2004 and 2010 from participants of the Singapore Multi Ethnic Cohort (MEC). Medical exclusion criteria for cohort participation were cancer, heart disease, stroke, renal failure and serious mental illness. Participants who were not working over the past 12 months and without data on sitting time were excluded from the analyses. Multivariable regression analyses were used to examine cross-sectional associations of self-reported age, gender, ethnicity, marital status, education, smoking, caloric intake and moderate-to-vigorous leisure time physical activity (LTPA) with self-reported occupational, leisure and total sitting time. Correlates were also studied separately for Chinese, Malays and Indians.
RESULTS: The final sample comprised 9384 participants (54.8% male): 50.5% were Chinese, 24.0% Malay, and 25.5% Indian. For the total sample, mean occupational sitting time was 2.71 h/day, mean leisure sitting time was 2.77 h/day and mean total sitting time was 5.48 h/day. Sitting time in all domains was highest among Chinese. Age, gender, education, and caloric intake were associated with higher occupational sitting time, while ethnicity, marital status and smoking were associated with lower occupational sitting time. Marital status, smoking, caloric intake and LTPA were associated with higher leisure sitting time, while age, gender and ethnicity were associated with lower leisure sitting time. Gender, marital status, education, caloric intake and LTPA were associated with higher total sitting time, while ethnicity was associated with lower total sitting time. Stratified analyses revealed different associations within sitting domains for Indians compared to Chinese and Malays.
CONCLUSION: Our findings highlight the need to focus on separate domains of sitting (occupational, leisure or total) when identifying which factors determine this behavior, and that the content of intervention programs should be tailored to domain-specific sitting rather than to sitting in general. Finally, our study showed ethnic differences and therefore we recommend to culturally target interventions.
Aim: To investigate the concurrent validity and reliability of the WBB for balance assessment in healthy young adults.
Methods: Thirty-two young adults participated in this study. Their ability to balance was tested while standing on a WBB and a laboratory-grade force platform, under three conditions: feet together with eyes open, feet together with eyes closed and semi-tandem standing with eyes open. They had 10 min resting period between tests. The agreement between the WBB and the laboratory-grade force platform was investigated, and the reliability of the WBB was determined.
Results: A poor agreement between the WBB and the laboratory-grade force platform was found for all standing conditions [intraclass correlation coefficient (ICC) = 0.03 to 0.07]. A moderate to high reliability was found for the WBB for balance assessment in healthy young adults (ICC = 0.66 to 0.76).
Conclusion: The WBB was found to be a reliable tool for static balance assessment in healthy young adults. However, it had poor validity compared to the laboratory-grade force platform.
Methodology: Thirty rats were treated to receive 0.5 mL phosphate-buffered saline (group A, control), 0.5 mL corn oil (group B), 0.2% CPZ (group C), for 6 weeks, 0.2% CPZ for 3 weeks and then 200 mg/kg of Kv for 3 weeks (group D), or 200 mg/kg of Kv for 3 weeks followed by 0.2% CPZ for 3 weeks (group E). Rats were assessed for exploratory functions and anxiety-like behaviour before being euthanised and perfused transcardially with 4% paraformaldehyde. Prefrontal and hippocampal thin sections were stained in hematoxylin and eosin and cresyl fast violet stains.
Results: CPZ-induced demyelination resulted in behavioural impairment as seen by reduced exploratory activities, rearing behaviour, stretch attend posture, center square entry, and anxiogenic characteristics. Degenerative changes including pyknosis, karyorrhexis, neuronal hypertrophy, and reduced Nissl integrity were also seen. Animals treated with Kv showed significant improvement in behavioural outcomes and a comparatively normal cytoarchitectural profile.
Conclusion: Kv provides protective roles against CPZ-induced neurotoxicity through prevention of ribosomal protein degradation.
OBJECTIVE: The aim of this study was to analyze the proximal thoracic (PT) flexibility and its compensatory ability above the "potential UIV."
SUMMARY OF BACKGROUND DATA: Shoulder and neck imbalance can be caused by overcorrection of the main thoracic (MT) curve due to inability of PT segment to compensate.
METHODS: Cervical supine side bending (CSB) radiographs of 100 Lenke 1 and 2 patients were studied. We further stratified Lenke 1 curves into Lenke 1-ve: PT side bending (PTSB) 80.0% of cases of the PT segment were unable to compensate at T3-T6. In Lenke 1+ve curves, 78.4% were unable to compensate at T6, followed by T5 (75.7%), T4 (73.0%), T3 (59.5%), T2 (27.0%), and T1 (21.6%). In Lenke 1-ve curves, 36.4% of cases were unable to compensate at T6, followed by T5 (45.5%), T4 (45.5%), T3 (30.3%), T2 (21.2%), and T1 (15.2%). A significant difference between Lenke 1-ve and Lenke 1+ve was observed from T3 to T6. The difference between Lenke 1+ve and Lenke 2 curves was significant only at T2.
CONCLUSION: The compensation ability and the flexibility of the PT segments of Lenke 1-ve and Lenke 1+ve curves were different. Lenke 1+ve curves demonstrated similar characteristics to Lenke 2 curves.
LEVEL OF EVIDENCE: 3.