Micro-CT assessment of changes in the morphology and position of the immature mandibular canal during early growth.

Abstract

The mandibular canal contributes to the development and growth of the mandible, as it acts as a conduit for the growing inferior alveolar neurovascular structures. A clear understanding of the canal's pathway is, therefore, important in interpreting the growth pattern of the inferior alveolar neurovascular bundle. This study investigated the position of the mandibular canal within the body of the mandible and its general dimensions within a pediatric collection of mandibles. The sample included 45 mandibles and was subdivided into three: group 1 (30 gestational weeks to birth), group 2 (birth to 12months), and group 3 (1 to 4years). Mandibles were scanned using a Nikon XTH 225L micro-CT unit. Scanning conditions ranged between 85kV/83µA and 100kV/100µA. Measurements included: the maximum width and height of the mandibular canal and distances between the mandibular canal and the relevant surfaces of the mandible. Data analysis included an ANOVA, MANOVA, and principal component analysis. The mandibular canal increased significantly in size from 30 gestational weeks to 12months relative to the deciduous molar crypts. Postnatally, the mandibular canal increased significantly in height at the level of the second deciduous molar crypt. The canal lies closer to the buccal surface in the region of the first and second deciduous molar teeth. The consistency in the positioning of the mandibular canal within the body of the mandible may assist in predicting the occurrence of aberrant growth patterns, particularly during the initial stages of growth.