6533b857fe1ef96bd12b4f7c

RESEARCH PRODUCT

Three-Dimensional Classification of Lower Third Molars and Their Relationship to the Mandibular Canal.

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description

PURPOSE To develop a novel classification making full use of radiographic three-dimensional (3D) information to describe the position, geometric configuration of a mandibular third molar (M3M) and its spatial relation to neighboring structures such as the mandibular canal (MC). The classification presented in this study helps to establish a common language and serves as a framework for further studies, for example, on 3D parameters influencing prognosis of the M3M and level of difficulty associated with its removal. MATERIAL AND METHODS A total of 8 parameters were included in the classification including position, the cranio-caudal height, the number of roots of the M3M as well as its spatial relationship to the MC, its course, its deformation, and distance to the M3M. The classification was retrospectively applied to a sample of 483 patients and these data were statistically evaluated. RESULTS The most commonly observed categories were the (+) vertical position (39.8%); the cranio-caudal height A (38.7%); 2 roots (83.2%); and the spatial relationship no contact caudal (37.5%). Contact between the M3M and inferior alveolar nerve was observed in 58% of all cases. A deformation of the MC was found in 81% of cases. CONCLUSIONS Our novel classification aims to provide a more holistic description of parameters defining 3D M3M position, as well as its spatial relation to relevant neighboring structures. It creates a uniform terminology that can be applied in practice by surgeons and radiologists, and also serves as a foundation for further research projects, such that results from similarly designed studies could be compared.