Abstract:

Objective　To provide anatomic basis for the mandibular dental implantation.　Methods　20 volunteers with healthy teeth were selected and scanned in series by spiral CT from the orbitomeatal line (OML). The mandibular canal was reconstructed by the curve-planar reconstruction(CPR) under the ADW 4.2 software. The position and composition of mandibular canal were observed, followed by the measurement of the distance from the dental root of mandibular posterior teeth to the superior wall of mandibular canal. The visual model of mandible and mandibular canal were reconstructed by the Amira 3D software. The course of mandibular canal in the diaphanous mandible and the relationship of mandibular posterior teeth with it were detected.　Results　The mandibular canal was composed of a thin compact bone and traveled through the bottom of lingual side of the molar and buccal side of the premolar. The lingual side of the madibular canal was thicker than that of other sides. In the diaphanous mandible, the mandibular canal could be clearly displayed, including its position, shape and course, and the distances from the mandibular canal to the inferior edge of mandibular body, alveolar crest and the medial, lateral plates of mandible respectively. The distance from the dental root of second molar to the mandibular canal was the nearest than that of the others, and the followed was the second molar, first molar, third molar, second premolar and first premolar by the near and far. The distance was nearer from the distal root of mandibular molar to the mandibular canal than that of the mesial root. The nearest distance from the dental root of first premolar, second premolar, first molar, second molar, third molar to the superior wall of mandibular canal were (8.38±1.04) mm(left) and (8.44±1.05) mm(right), (7.51±0.85) mm, (3.40±0.65) mm, (2.93±0.61) mm, (3.92±0.63) mm(left) and (3.97±0.63) mm(right) separately.　Conclusions　Three-dimensional reconstruction and analysis of mandibular canal is valuable for choosing appropriate length of dental implantation and avoiding to injury the inferior alveolar nerve during the operation.

Key words: Mandibular canal, Three-dimensional reconstruction, Visualization, Dental implantation