The Oral and Systemic Impact of Third Molar Periodontal Pathology

Purpose

Analyze in pregnant subjects the relationship between third molar periodontal pathology, and subjects’ overall periodontal status. Assess also, the associations between postpartum periodontal status by jaw and a systemic impact, preterm birth, or elevated serum C-reactive protein (CRP).

Patients and Methods

Data were from an IRB-approved study, Oral Conditions and Pregnancy. In this clinical study, full-mouth periodontal examinations including third molars were conducted at greater than 24 weeks of pregnancy and again within 72 hours of delivery. For our analyses, mean periodontal probing depth (PD) by visible tooth and by jaw were calculated at enrollment and postpartum. Subjects were categorized by 3 broad levels of periodontal health, considered the primary outcome variable. The primary predictor variable for levels of periodontal health was the presence or absence of visible third molars. Mean periodontal probing depth in the mandible or maxilla at term was considered an indicator of a possible risk of systemic exposure, increasing the odds of preterm birth, less than 37 weeks gestation, or elevated serum CRP levels. Chi-square and t tests were used to determine statistical significance, .05. Significant predictor variables were included in multivariable models. Unconditional logistic multivariate models were used to derive odds ratios (OR) and 95% confidence intervals (CI).

Results

Data from examinations at enrollment and postpartum were available for 1,020 and 891 subjects, respectively. Visible third molars were detected in 405 subjects at enrollment and in 360 subjects at term. No subjects had third molars removed during the study. At enrollment and postpartum, subjects with visible third molars were significantly more likely to have moderate/severe periodontal disease, 23.5% versus 8.5%, and 18.3 versus 9.4%, respectively. Mean PD was significantly greater for maxillary and mandibular molars than for more anterior teeth, P < .01. In both jaws, mean PD tended to be progressively greater from first to third molars. No differences were found in mean PD by jaw. In subjects with visible third molars, adjusting for the severity of mandibular periodontal disease, the level of maxillary periodontal disease was significantly associated with preterm birth, P < .01, OR 2.6 (95% CI 1.1–6.8), or the upper quartile of serum CRP at term, at least 23.0 mg/L postpartum, P = .05, OR 2.5 (95% CI 1.2–5.1).

Conclusions

Subjects’ detected levels of periodontal disease were greater at enrollment and postpartum if visible third molars were detected.