Chávez-Lomeli M E, Mansilla Lory J, Pompa J A, Kjaer I
Center for Craniofacial Biology, Latin American University, Mexico City, Mexico.
J Dent Res. 1996 Aug;75(8):1540-4. doi: 10.1177/00220345960750080401.
The purpose of this study was to describe the prenatal formation of the human mandibular canal. Since bony canals develop in prenatal life around the nerve paths, it was assumed that the canal pattern could reflect the pattern of innervation of the dentition. Mapping of this early canal pattern does not appear to have been undertaken before. The material consisted of anthropological mandibles from the National Institute of Anthropology and History, Mexico City. A total of 302 human hemimandibles from the latter half of the prenatal period was investigated. The length, measured from the mental symphysis to the mandibular condyle, ranged from 28 to 60 mm. The dento-alveolar maturity was classified in two stages according to the appearance of alveolar sockets of deciduous and first permanent molars. The mandibles were radiographed with guttapercha points inserted into the canal openings (foramina) on the lingual surfaces of the mandibular rami. The study showed that the canal to the incisors appeared first, followed by the canal to the primary molars, and last by the one or more canals to the first permanent molars. In the most mature group, three different canals always occurred in each hemimandible. The canals were directed from the lingual surface of the mandibular ramus toward the different tooth groups. The inferior alveolar nerve presumably occurs in the mandible as three individual nerve paths originating at different stages of development. It is suggested that rapid prenatal growth and remodeling in the ramus region result in a gradual coalescence of the canal entrances that is obvious at birth. It is hypothesized that the pattern of tooth agenesis within the three groups of teeth is related to the three separate paths of innervation of the dentition.
本研究的目的是描述人类下颌管的产前形成过程。由于骨管在产前围绕神经路径发育，因此推测管的形态可能反映牙列的神经支配模式。此前似乎尚未对这种早期管形态进行过测绘。研究材料包括来自墨西哥城国家人类学和历史研究所的人类学下颌骨。共研究了302个来自产前后期的人类半侧下颌骨。从颏联合到下颌髁突测量的长度范围为28至60毫米。根据乳牙和第一恒磨牙牙槽窝的出现情况，将牙-牙槽成熟度分为两个阶段。将牙胶尖插入下颌支舌面的管开口（孔）中，对下颌骨进行X线摄影。研究表明，通向切牙的管最先出现，其次是通向乳磨牙的管，最后是通向第一恒磨牙的一条或多条管。在最成熟的组中，每个半侧下颌骨总是出现三种不同的管。这些管从下颌支的舌面向不同的牙组延伸。下牙槽神经可能以下颌骨中三条在不同发育阶段起源的独立神经路径出现。有人认为，下颌支区域产前的快速生长和重塑导致管入口在出生时明显逐渐合并。据推测，三组牙齿中牙缺失的模式与牙列的三条独立神经支配路径有关。
