The Presence of Visible Third Molars Negatively Influences Periodontal Outcomes in the Maternal Oral Therapy to Reduce Obstetric Risk Study

PurposeTo assess the relationship between the presence or absence of visible third molars and outcomes for periodontal inflammatory disease.MethodsObstetric subjects, at enrollment in an institutional review board–approved, multisite study, Maternal Oral Therapy to Reduce Obstetric Risk (N = 1,798), were divided into 2 groups, those with no visible third molars (n = 692) and those with at least 1 visible third molar (n = 1,106), the predictor variables for this study. The principal outcome variables were the patient-level periodontal status of the first/second molars: mean periodontal probing depths, mean attachment levels, and mean extent scores. Periodontal disease severity also was assessed by criteria from the Oral Conditions and Pregnancy trial and the Centers for Disease Control and Prevention/American Academy of Periodontology. Outcomes according to the presence or absence of third molars were compared with χ2 statistics and multivariable analyses. Significance was set at P < .05.ResultsSignificantly more subjects had at least 1 third molar (62%) as compared with subjects with no visible third molar (38%) (P < .01). Ethnic characteristics of the 2 groups were similar. Overall, more subjects were white (61%), with most identifying their ethnicity as Latino. African-American subjects were well represented (37%). Subjects with a visible third molar were more likely to be significantly older, to be receiving medical assistance, and to have used tobacco before pregnancy. If subjects had at least 1 visible third molar, the mean first/second molar probing depths, attachment levels, and scores for bleeding on probing were significantly greater even after adjustment for covariates. On the basis of either Oral Conditions and Pregnancy criteria or Centers for Disease Control and Prevention/American Academy of Periodontology criteria, subjects were significantly more likely to have moderate or severe periodontal disease if a third molar was detected.ConclusionIf at least 1 visible third molar was detected in subjects in the Maternal Oral Therapy to Reduce Obstetric Risk study at enrollment as compared with no detected third molars, periodontal outcomes were significantly worse.