Available bone morphology and status of neural structures in the mandibular interforaminal region: three-dimensional analysis of anatomical structures

Abstract

Purpose: This study aimed to clarify the size and morphology of the mandible and to determine state of neural structures for the planning of the dental implantation using cone-beam computerized tomography (CBCT).

Methods: Of the 252 patients, CBCT images of 48 selected patients were evaluated. The bone height and width were measured and the type of the mental portion of the inferior alveolar canal, the anterior loop length (ALL), the location of the incisive canal and lingual foramen were identified with cross-sectional and multiplane reformatted CBCT images. According to buccal and lingual concavities, the shape of the mandible is classified as type A, B and C.

Results: Bone widths of males were significantly higher than female (p < 0.05). The thickest part of the alveolar bone was measured in the middle triple zone (d line) and the thinnest part was measured in the area near the alveolar crest (b line). The most seen type of mandible was type B (45.8%) that mandible was concave on the buccal side. Bone heights had a tendency to increase towards to the anterior mandible, and bone height in male patients was slightly but not significantly greater than that in female patients. ALL was 4.2 ± 1.2 mm and visible incisive canal length on CBCT was 9.7 ± 3.8 mm.

Conclusion: CBCT assessment of morphological features of the alveolar bone and locations of nerve canals and foramina in the anterior-premolar region of mandible represent useful practical anatomical information about the interforaminal region. This information is the guide to the dentist before implant surgery.

Keywords: Anterior loop; CBCT; Incisive canal; Lingual foramen; Mandible size.