Nature and Prevalence of Bacterial Taxa Persisting after Root Canal Chemomechanical Preparation in Permanent Teeth: A Systematic Review and Meta-analysis.

INTRODUCTION: Culture-independent molecular studies have shown a broad spectrum of bacterial taxa that persist after chemomechanical procedures (CMP). Therefore, this study systematically reviewed these reports to explore the prevalence of bacteria in post-instrumentation samples of root canals from permanent teeth, especially of as-yet-uncultivated/difficult-to-culture bacteria. METHODS: Electronic databases were searched from 2007 to January 2021. Clinical studies using culture-independent molecular methods to identify species-level taxa before and after CMP were included. Studies were critically appraised using the Joanna Briggs Institute Prevalence Critical Appraisal Checklist and the funnel plot analysis. The meta-analysis was performed on the prevalence of as-yet-uncultivated/difficult-to-culture bacterial taxa using RStudio. RESULTS: A total of 3781 titles were screened, but only 20 studies were included. The most frequent species in post-instrumentation samples were Streptococcus spp., Leptotrichia buccalis, Fusobacterium nucleatum, and Capnocytophaga ochracea. The detection frequency of some species increased after CMP, including mainly Firmicutes members such as streptococci, Enterococcus faecium, Selenomonas noxia, and Solobacterium moorei. The prevalence (confidence interval) of difficult-to-culture species was as follows: Dialister invisus, 17% (7%-29%); Solobacterium moorei, 14% (8%-23%); Bacteroidaceae [G-1] bacterium HMT 272, 13% (5%-23%); and Filifactor alocis, 11% (3%-23%). CONCLUSIONS: The prevalence of as-yet-uncultivated/difficult-to-culture bacterial taxa in post-instrumentation samples was low. The persistent species belonged mainly to the phylum Firmicutes, and streptococci were the major members. Future larger clinical studies on the composition of the whole bacterial community that persist after CMP are still necessary for a better understanding of bacterial interactions and their clinical significance in the treatment outcome.

A self-report joint damage and musculoskeletal disorders data among dentists: a cross-sectional study.

BACKGROUND: Musculoskeletal disorders (MSD) are an occupational health problem that demands a high cost and may also reduce the quality of life and productivity of the dentists. The aim of this study was to evaluate the prevalence of MSD and its association with self-reported joint damage in dentists from São Paulo (Brazil). METHODS: This was a cross-sectional study performed from two self-administered questionnaires - the Nordic Musculoskeletal Questionnaire and the other containing demographic and occupational data - in 6072 dentists. Between April and May 2014, 5885 questionnaires were distributed via e-mail through São Paulo Regional Board of Dentistry (CRO-SP) and 187 in Congress and public offices. Multivariable logistic regression was used to assess the association between explanatory variables (sex, age, level of education, duration of practice in years, number of patients seen per day, previous receipt of information about ergonomics, physical activity, and the presence of joint damage) and MSD. RESULTS: Two hundred eighty-six valid questionnaires were returned. The prevalence of MSD was 63.6% (N.=182). Multivariable logistic regression showed that only the factor of self-reported joint damage has a significant association with MSD (OR 0.001; 95% CI: 0.000-0.007). Concerning the self-reported joint damage (60.1%), the carpal tunnel syndrome was the most frequent (13.2%). CONCLUSIONS: The prevalence of MSD in dentists from São Paulo is high, and carpal tunnel syndrome is the most common self-reported joint damage.