Orthodontic Treatment and Central Incisors: a Study by CBCT Analysis

Abstract

To determine potential risks and critical orthodontic movements of central incisors. CBCT analysis of 66 patients (aged 12-38 years; 30 adolescents and 36 adults; 33 males and 33 females). We evaluated alveolar bones (crests, plates, ridges) surrounding central incisors from buccal and lingual sides, and at multiple levels using the "Ez3D-plus" program with regard to buccolingual inclination and effective length of premaxilla/length of the mental protuberance. We identified: - Potential risks in the maxilla, in case of 1) Proclined central incisors, on the first buccal coronal third and lingual side of alveolar bone. 2) ELP < 13 mm, with buccal movement. - Potential risks in mandible, in case of 1) Retroclined central incisors, on the first lingual coronal third and buccal apical two-thirds of alveolar bone. 2) LMP > 9 mm. - Critical orthodontic movements: 1) Buccal tipping of mandibular central incisors is more critical in adolescents. 2) Lingual tipping of mandibular central incisors is more critical than of maxillary ones in all groups, at the level of the alveolar crest. In adult males, at the first lingual coronal third of the alveolar plate. In adult females, at the buccal apical level. 3) Movement towards cortical bone: In all groups, buccal movements of maxillary central incisors are more critical than of mandibular ones, and lingual movements of mandibular central incisors are more critical than of maxillary ones, especially in adult males. We recommend an accurate diagnosis of incisors position and alveolar bone status, and planning of orthodontic treatment at an earlier age.