Periodontal disease progression with retained third molars

Abstract

Blakey et al reported that 25% of 325 young, asymptomatic patients enrolled in a longitudinal trial had at least one periodontal probing depth ≥5 mm (PD) on the distal of a second molar or on a third molar. Almost all of the patients had at least 2 mm of attachment loss accompanying the increased PD, confirming a diagnosis of periodontitis in the third molar region. These same patients were otherwise periodontally healthy. Young adult patients are usually not examined for periodontal disease and most clinical studies do not assess the third molar region of the mouth. The patients, enrolled in the IRB approved clinical trial at the University of Kentucky and the University of North Carolina with all four retained third molars, were examined yearly for periodontal changes. Full mouth periodontal probing, six sites per tooth, was conducted to determine periodontal status. All patients had a periodontal prophylaxis at each follow-up visit after data collection. Panoramic radiographs were analyzed for third molar angulation and degree of eruption. Clinical periodontal data were available for analysis from baseline and 3 years of follow-up for 195 patients. At baseline 59% of this cohort of patients had at least one PD ≥4 mm on the distal of a second molar or around a third molar; 21% had a PD ≥5 mm. Over time one fifth of the patients had an increase in PD of at least 2 mm; 89% with a ≥2 mm increase in PD had at least a 4 mm PD at baseline. With an increase in PD ≥2 mm, the involved third molars were more likely to be at the occlusal plane and vertical or distal in angulation as compared to the second molar. Data on periodontal disease from this longitudinal clinical trial suggest that periodontitis in the third molar region is more common in young patients than was expected. Further study may evolve predictors for periodontitis associated with third molars. References Blakey GH, Marciani RD, Haug RH, et al: Periodontal pathology associated with asymptomatic third molars. J Oral Maxillofac Surg 60:1227, 2002 Jacks TM, White RP Jr, Offenbacher S, et al: Progression of periodontitis in the second/third molar region in patients with asymptomatic third molars.