Association between metabolic syndrome and tooth loss: A systematic review and meta-analysis.

BACKGROUND: The authors conducted a systematic review and meta-analysis to verify the existence and level of scientific evidence concerning the association between metabolic syndrome (MetS), as the main exposure, and tooth loss (TL), as the outcome. TYPES OF STUDIES REVIEWED: Through electronic databases and partially through gray literature, the authors identified observational studies in adults. The authors used no date or language restrictions. The authors evaluated the studies' methodological quality by using the Newcastle-Ottawa Scale. The authors conducted a random-effects model meta-analysis. The authors assessed the quality of evidence by using the Grading of Recommendations Assessment, Development and Evaluation criteria. RESULTS: Twelve studies met the eligibility criteria, and 9 were retained for the meta-analysis. Most were cross-sectional studies with good methodological quality. Participants with MetS had fewer teeth (standardized mean difference, -2.77; 95% confidence interval, -4.56 to -0.98) and an increased likelihood of lacking functional dentition (odds ratio, 2.37; 95% confidence interval, 1.89 to 2.96) than did those without MetS. The overall quality of evidence was very low. CONCLUSIONS AND PRACTICAL IMPLICATIONS: Better-conducted longitudinal studies are necessary to establish a causal relationship between MetS and TL to inform the best strategies to prevent TL in populations with MetS.

Inequality of water fluoridation in Southern Brazil--the inverse equity hypothesis revisited.

The purpose of this ecological study was to investigate the association between social and economic indicators at the municipal level and the presence of water fluoridation and time when water fluoridation was implemented in the 293 municipalities of Santa Catarina State in Southern Brazil. Several social and economic indicators were obtained from official Brazilian agencies as well as from UNICEF. Questionnaires were sent to local authorities and to the local government water supply Company to obtain information about the presence or not of a fluoridated water supply and the year when fluoridation was implemented. Differences in social and economic indicators between municipalities with and without fluoridated water and between those that have had this service for different lengths of time were compared by the Mann-Whitney U test. In addition, multiple logistic regression analyses was performed to identify associations between social and economic indicators at the municipal level and presence and time of implementation of water fluoridation. Results indicated that larger populations are associated with municipalities with fluoridated water. Larger populations, higher child development indexes and low illiteracy rates are associated with a longer time since the implementation of water fluoridation. The finding that less developed municipalities delayed the provision of water fluoridation corroborates the inverse equity hypothesis.