Perioperative validation of localisation of the mental foramen

Aim: To assess the accuracy of panoramic radiography and spiral or computed tomography for the localisation of the mental foramen. Materials and methods: The distance from the alveolar crest to the mental foramen was measured from panoramic radiographs, spiral tomograms and CT scans. The same distance was measured during implant surgery using a specially designed caliper. Results: Panoramic radiography showed more deviation (+0.6 mm) from the perioperative measurements than either spiral or computed tomography (+0.4 and -0.3 mm. respectively). The difference was significant (P<0.05). In general, distances were overestimated on the panoramic radiographs. Conclusions: Cross-sectional imaging techniques are recommended for the pre-operative planning of implants in the posterior mandible.