Caries Experience and Periodontal Pathology in Erupting Third Molars

Objectives: Document the prevalence of occlusal caries experience and periodontal pathology for erupting 3rd molars in young adults.

Methods: Data are from 49 subjects enrolled in an IRB-approved trial with at least one 3rd molar below the occlusal plane at baseline that erupted by longest follow-up. Teeth that reached the occlusal plane were considered erupted.

Caries experience on the occlusal surface of 3rd molars was assessed by a visual-tactile examination. At least one periodontal probing depth (PD)>4mm in the 3rd molar region was considered indicative of periodontal pathology. The 3rd molar region was defined as the 6 probing sites around 3rd molars and 2 sites on the distal of 2nd molars.

Prevalence of 3rd molar caries experience and periodontal pathology at longest follow-up was assessed.

Results: The majority of the 49 subjects were female, 51%, Caucasian 76%, and educated at least through high school, 82%. Median age was 20.5 years (IQ 18.4-24.1). Median follow-up was 5.1 years (IQ 3.4-6.9). At baseline no subjects had occlusal caries experience in a 3rd molar; 51% of subjects had at least one PD>4mm in a 3rd molar region.

At follow-up 27% of subjects had occlusal caries experience in at least one 3rd molar that erupted to the occlusal plane, and 61% of subjects had at least one PD>4mm in a 3rd molar region. Twenty-nine percent had occlusal caries in at least one 3rd molar at the occlusal plane and at least one PD>4mm in a 3rd molar region; 37% had neither 3rd molar occlusal caries experience or a PD>4mm in a 3rd molar region.

Conclusions: For 3rd molars that erupted “late,” periodontal pathology was more prevalent approximately 5 years after initial examination than occlusal caries.

Funding: Oral and Maxillofacial Surgery Foundation, American Association of Oral and Maxillofacial Surgeons, Dental Foundation of North Carolina