Relationship between anterior mandibular bone thickness and the angulation of incisors and canines-a CBCT study.

OBJECTIVES: The morphology of the maxillary and mandibular alveolar cortex plays an important role in the planning of orthodontic treatment. Cone-beam computed tomography (CBCT) provides a precise demonstration of anatomical structures. Therefore, the aim of this paper was to evaluate what influence the position of incisors and canines have on the dimensions of the cortical and spongious bone of the anterior mandibular alveolar process.

MATERIALS AND METHODS: The material consisted of 100 CBCT volumes (61 females and 39 males, aged 18-71 years) obtained by means of a Gendex GXCB-500 machine and analysed using i-CAT Vision and CorelDRAW 9 software. Several linear and angular measurements were taken of cortical and spongious mandibular, vestibular and lingual alveolar bone.

RESULTS: The thickness of the vestibular spongious bone increased around lateral incisors and canines together with dental axis inclination, as did the thickness of the lingual spongious bone around central incisors and canines with greater angles of vestibular cortex curvature. In all teeth, the thickness of lingual cancellous bone decreased along with increase of the angle of tooth inclination. In the case of almost all groups of teeth, the thickness of lingual cancellous bone around teeth declined as the angle of curvature of the cortical bone decreased. The rotation of mandibular incisors and canines did not affect the thickness of the surrounding bone.

CONCLUSIONS: The position of teeth has little influence on vestibular bone thickness and is only significant around central incisors. In the case of almost all groups of teeth, the thickness of lingual spongious bone around teeth declined as the angle of curvature of the cortical bone decreased.

CLINICAL RELEVANCE: CBCT is a diagnostic tool that provides detailed information on the dimensions of the anterior dentate mandibular alveolar process.