Change in Third Molar Angulation and Position in Young Adults and Follow-Up Periodontal Pathology
Purpose
This study was designed to assess changes in third molar position and angulation in young adults and the resulting third molar periodontal probing (PD) status.
Patients and Methods
Data derived from patients with 4 asymptomatic third molars with adjacent second molars enrolled in an institutional review board approved longitudinal trial. Inclusion criteria for the trial dictated that patients be healthy and 14 to 45 years of age. Panoramic radiographs were analyzed for third molar angulation as compared with the long axis of the second molar (mesial/horizontal ≥25°) and eruption to the occlusal plane. Full mouth PD including third molars was conducted at follow-up. At follow-up, PD ≥4 mm distal of second molars or around third molars was considered important clinically.
Results
Data from 237 patients were available. Median age was 25.9 years (interquartile range [IQ], 22.1 years, 32.8 years). With a median follow-up of 2.2 years (IQ, 2.0 years, 3.7 years), 44% of impacted maxillary third and 26% of impacted mandibular third molars changed angulation or position. One third of vertical/distal impacted third molars in both jaws and 11% mesial/horizontal mandibular third molars erupted to the occlusal plane during follow-up from baseline. If mandibular third molar angulation as compared with the long axis of the second molar was mesial/horizontal ≥35°, only 3% erupted to the occlusal plane. At follow-up, 11% of the 125 impacted maxillary third and 29% of the 133 impacted mandibular third molars had PD ≥4 mm. Similarly, 11% of the 307 maxillary third molars at the occlusal plane had PD ≥4 mm, but 51% of the 312 erupted mandibular third molars were affected.
Conclusion
A change in third molar position or angulation was common. Erupted mandibular third molars were more likely to have PD ≥4 mm.
⁎Clinical Research Fellow, Oral and Maxillofacial Surgery
†Dalton L. McMichael Professor, Department of Oral and Maxillofacial Surgery
‡OraPharma Distinguished Professor, Department of Periodontology
∥Clinical Assistant Professor, Department of Oral and Maxillofacial Surgery
¶Professor, Department of Oral and Maxillofacial Surgery; Associate Dean, College of Dentistry, University of Kentucky, Lexington, KY
Address correspondence and reprint requests to Dr White: School of Dentistry, University of North Carolina, Department of Oral and Maxillofacial Surgery, CB 7450, Chapel Hill, NC 27599-7450
Received from the School of Dentistry, University of North Carolina, Chapel Hill, NC.
Supported in part by the Oral and Maxillofacial Surgery Foundation, the American Association of Oral and Maxillofacial Surgeons, and the Dental Foundation of North Carolina.
ABSTRACT