Second molar periodontal inflammatory disease after third molar removal in young adults

To assess the prevalence of periodontal inflammatory disease on the distal side of second molars after third molar removal and the association between presurgical and surgical variables and postsurgical periodontal outcomes.

Data before and after surgery from 2 studies approved by an institutional review board were used. In 1 study, 26 subjects had 4 asymptomatic third molars and in the other 49 subjects had at least 1 mandibular third molar with symptoms of pericoronitis. Full-mouth periodontal probing data, 6 sites per tooth, were obtained as a measurement of periodontal status before and after surgery. A probing depth (PD) ≥4 mm on either of the 2 possible probing sites on the distal side of any second molar (D2M) served as an indicator of periodontal inflammatory disease; periodontal health was defined as all D2M PD <4 mm. Cochran-Mantel-Haenszel row mean score tests compared the subjects' postsurgical periodontal status (all D2M PD <4 mm and at least 1 D2M PD ≥4 mm) with respect to age and time intervals, and the Fisher exact test was used to compare ethnicity, gender, and clinical data at surgery. The McNemar test was used to assess the discordance between subjects' pre- and postsurgical periodontal status. The level of significance was set at .05.

Of the 75 subjects, 52% were women and 65% were white. The median age at surgery was 23.6 years (interquartile range, 20.9 to 26.6 years). At enrollment, 53 of 75 subjects (71%) had at least 1 D2M PD ≥4 mm. Subjects were significantly more likely to have an improved D2M periodontal status after surgery than a deteriorated status (P < .01). Fewer subjects, 17 of 75 (24%), had at least 1 D2M PD ≥4 mm after surgery. D2M PD ≥4 mm was more likely after surgery if presurgical D2M was PD ≥4 mm (P < .01). Gender, ethnicity, age, presurgical symptoms, and data estimating the extensiveness of surgery were not significantly associated with postsurgical D2M periodontal outcomes.

After third molar removal, periodontal inflammatory disease on the distal of D2Ms was detected significantly less often. None of the variables examined except for presurgical presence of D2M PD ≥4 mm were significantly associated with postsurgical D2M periodontal inflammatory disease.