Abstract The aim of the present study was to evaluate the association between metabolic syndrome (MS) and periodontitis (PD), through a systematic review and meta-analysis. Original observational studies assessing the association between MS and PD in adults, published before May 11th (2017), were identified through electronic searches of MEDLINE, EMBASE and Cochrane Library databases. The PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guideline was used. For studies to be included, they had to mention the criteria used to diagnose MS and to have used at least one clinical measure to diagnose PD. There was no language restriction. Three reviewers independently identified eligible studies for possible inclusion in the systematic review and meta-analysis. The quality of the studies was evaluated by the Newcastle-Ottawa scale for observational studies. A random model meta-analysis was conducted. The strategies used to investigate heterogeneity were sequential analysis, subgroup analysis, univariate meta-regression and sensitivity analysis. Thirty-three studies met the inclusion criteria for the systematic review, and 26 had enough information to be included in the meta-analysis, totaling 52,504 patients. MS and PD were associated with an odds ratio of 1.38 (95%CI 1.26–1.51; I2 = 92.7%; p < 0.001). Subgroup analysis showed that complete periodontal examination (I2 = 70.6%; p < 0.001) partially explained the variability between studies. The present findings suggest an association between MS and PD. Individuals with MS are 38% more likely to present PD than individuals without this condition. Prospective studies should be conducted to establish cause and effect relations between MS and PD.
Abstract Halitosis is still poorly studied in young adults. The aim of this study was to evaluate the occurrence of self-reported halitosis and associate it with demographic and behavioral factors in young adult dental students. This cross-sectional study was designed as a census of students enrolled in three initial and three final semesters of a dental course in a Brazilian public university. Of 284 eligible students, 257 (90.5%) completed a self-administered questionnaire. Self-reported halitosis was the primary study outcome, and was assessed with the question “do you feel you have bad breath?”. Data on age, gender, frequency of tooth brushing and interproximal cleaning, tongue cleaning, mouth rinse use and dry mouth were collected using the questionnaire, and were considered independent variables. Of the students surveyed, 26.5% reported as never, 51.7% as rarely, 21.4% as sometimes, and 0.4% as always feeling they had halitosis. Morning halitosis was reported by 90.6% of those who reported halitosis. In the final multiple model, last semester students had a 55% lower chance of reporting halitosis, compared with students from the first semesters [odds ratio (OR) 0.46; 95%CI 0.24–0.89]. Women had a 2.57fold higher chance of reporting halitosis (OR = 2.57; 95%CI 1.12–5.93). Dry mouth increased the chance of self-reported halitosis 3.95-fold, compared with absence of dry mouth (OR = 3.95; 95%CI 2.03–7.68). It can be concluded that self-reports of halitosis were low among dental students, but may represent an important complaint. Gender, dry mouth and level of college education of the dentist were factors significantly associated with self-reported halitosis.