Buccolingual alveolar bone condition of mandibular molar distalization in skeletal class III patients

Abstract

Objective: To investigate the alveolar bone condition of mandibular molar distalization in skeletal Class III patients from buccolingual direction. Methods: 45 skeletal class III patients were recruited. The alveolar bone volume, buccal cortical bone thickness and lingual cortical bone thickness were measured in five planes from mesial to distal and at five depths from gingival to root. The effects of the gender of the patients, the second molar lingual inclination, and wisdom tooth on alveolar bone volume and cortical bone thickness were evaluated. To explore the effect of wisdom tooth extraction on alveolar bone condition, the measurements before and after wisdom tooth extraction were compared. Results: The impacted wisdom tooth had significantly greater alveolar bone volume and thicker buccal cortical bone at cervical third of molar, while the erupted wisdom tooth had greater alveolar bone volume at apical third. After wisdom tooth extraction, these advantages would weaken owing to the reconstruction of alveolar bone. Patients with lingual inclined molar were observed to own thicker lingual cortical bone. Male tended to have greater alveolar bone volume, but no significant differences were shown in this study. Conclusions: The growth of wisdom tooth and the second molar lingual inclination can effectively make the alveolar bone condition more favorable for mandibular molar distalization, but gender has trivial effects on alveolar bone condition. Shortly after the wisdom tooth extraction surgery, the better bone condition can be maintained.