[Prevalence of serologic markers of hepatitis B in dentistry students and dentists in Belo Horizonte, Brazil].

The main objective of this transverse study was to investigate the presence of serologic markers of infection with the hepatitis B virus (HBsAg or HBsAb) among dentistry students before and after they began to have contact with patients; among dentists; and, for purposes of comparison with the latter group, among professionals outside the biological sciences in the municipality of Belo Horizonte, Brazil. Secondarily, the association between the prevalence of infection, the frequency of performing potentially infective dental procedures, and the use of protective barriers was studied. Among 88 students at the beginning of their course of study (average age = 20.0 years), the proportion of positive individuals was 6.8%; among 84 students concluding their studies (average age = 23.4 years), the proportion was 7.1% (P = 0.829). In the group of 202 dentists (average age = 44.0 years), 23.3% were positive, while among the other professionals (202 individuals, average age = 44.3 years), the proportion was 14.9%, for an odds ratio of 1.75 (95% CI = 1.02 to 2.98; P = 0.042). While 91.7% of the students reported that they routinely used surgical masks, only 16.7% said they regularly wore gloves. Among the dentists, these proportions were 49.8% and 9.4%, respectively. No association was found between risk factors and the use of such protection and the prevalence of infection in the different groups studied.