STABILITY OF PERIODONTAL HEALING DISTAL TO THE MANDIBULAR SECOND MOLAR AFTER THIRD MOLAR CORONECTOMY: A 3-YEAR FOLLOW-UP STUDY.

PURPOSE: The stability of the periodontal attachment distal to the mandibular second molar after coronectomy of the third molar is still unclear. This study addressed the question of whether periodontal measures are stable over time among patients undergoing coronectomy. MATERIALS AND METHODS: This prospective cohort study enrolled 30 patients treated at the Unit of Oral and Maxillofacial Surgery of the University of Bologna. The predictor variables were the probing pocket depth (PPD), distance between the marginal crest and the bottom of the osseous defect (BOD), and distance between the cementoenamel junction and the BOD. Three points on the distal surface of the second molar were recorded: distobuccal, distomedial, and distolingual sites. The distobuccal site was used as the statistical unit. The Wilcoxon test for paired data and Kendall τb were used to evaluate all variables. The significance level was set at P < .05. RESULTS: The 3-year follow-up was completed by 27 patients (7 male and 20 female patients; mean age, 28 ± 7 years) with 30 third molars. At 3 years, the PPD was 4 ± 1.25 mm; no significant changes in PPD were recorded for all sites from 9 months to 3 years. For the marginal crest-BOD distance and the cementoenamel junction-BOD distance, significant reductions were evident between preoperative values and those at 9 to 36 months (P = .001) and between values at 9 and 36 months (P = .02). CONCLUSIONS: A clinical healthy periodontium distal to the second molar was observed 36 months after coronectomy. However, further studies are necessary to confirm these preliminary clinical results.