Intraoperative Measurement of the Distance from the Bottom of Osteotomy to the Mandibular Canal Using a Novel Ultrasonic Device

Background: In our previous study, we found that a novel ultrasound (US) device may serve as a useful intraoperative tool to measure the distance from osteotomy to the inferior alveolar canal (IAC). Purpose: To validate our previous results in a larger group of osteotomies in the posterior mandible. Methods: During dental implant placement surgery, osteotomies were created using a standardized 2-mm-diameter pilot drill. The distance from the bottom of the osteotome to the IAC was assessed using an ultrasonic device and compared with a standard panoramic radiograph used to measure the same residual distance. The total distance from the crestal bone to the IAC was measured on a preoperative computed tomography (CT) and compared with total US measurements by summing the drill depth with residual depth measurements. Results: Mean radiographic and US residual distances were 5.19+/-1.95 mm, 5.01+/-1.82 mm, p = 0.79 respectively. These measurements presented strong positive correlations (r = 0.61, p =.01). Mean total CT distance was 13.48+/-2.66 mm; mean total US calculation was 13.69+/-2.51 mm. No significant difference was found (p >.05). Conclusions: The results support our previous pilot study and confirm that the tested US device identifies the IAC and measures the distance from the osteotomy to the roof of the mandibular canal.