Surgical removal of third molars and periodontal tissues of adjacent second molars

The aim of this study was to investigate the effect of mandibular third-molar (M3) removal on periodontal health of adjacent second molars (M2). Probing pocket depths (PPD) and probing attachment levels (PAL) have been described for primary outcome. As cofactors involved, gender, complications, two suture materials and two types of impaction were chosen as secondary outcomes.

Seventy-eight patients (49 female; mean age: 16.0 ± 2.0 years) with 78 asymptomatic impacted mandibular M3 were included in this study. Plaque and gingival indices, PPD and PAL were recorded prior and 6 months after surgery. Impacted teeth were classified as either fully impacted (completely within in the bone) or submucosal (fully covered by oral mucosa).

Average baseline PPD was reduced from 3.3 mm to 2.6 mm after 6 months (p < 0.05). Average PAL was reduced from 3.0 to 2.5 mm (p < 0.05). Preoperative PPD ≥ 4 mm at the distolingual and distobuccal sites was positively correlated with clinical improvement (PPD: p < 0.05; PAL: p < 0.05). The impaction class was also identified as positive cofactor for PPD (p = 0.039), but not for PAL.

Young patients may benefit from an early removal of mandibular M3, especially in the presence of certain cofactors.