TEMPERATURE-CHANGES IN BOVINE MANDIBULAR BONE DURING IMPLANT SITE PREPARATION - AN ASSESSMENT USING INFRARED THERMOGRAPHY

Objectives: Changes in bone temperature during the sequence of drillin g for implant site preparation using the Branemark technique were moni tored using infra-red thermography. Methods: Bovine mandibles were use d to provide cortical bone of a similar quality to human mandibular bo ne. To ensure the consistency in the drilling procedure, one operator used a conventional dental handpiece with a motor provided by Nobelpha rma. The manufacturer's specifications were followed during the implan t site preparation, except that no irrigation was employed since infra -red radiation does not transmit through water. Thermal images were re corded using the Thermovision 900 system. A sequence of images was rec orded during implant site preparation. Three drills were examined in t erms of temperature changes during drilling over the entire area invol ved. The three drills used were a round bur, which determines the site of the fixture, a spiral drill (2 mm twist drill) which establishes t he direction of the implant and finally a pilot drill (3 mm) which pro gressively increases the diameter of the site. Results: Average values (n = 10 drill sequences) for maximum recorded temperature (Max T degr ees C), change in temperature (Delta T degrees C) from baseline and th e area of involvement (mm(2)) for each drill in the 10 drill sequences were as follows: round, spiral (2 mm) and pilot (3 mm) drills gave ma ximum temperatures of 82.7 degrees C, 130.1 degrees C and 126.3 degree s C, respectively. The changes in temperature, Delta T degrees C, were 45.7 degrees C, 79.0 degrees C and 78.9 degrees C for the round, 2 mm twist and 3 mm pilot drill, respectively. The average areas recorded for the round, spiral and pilot drills were 49 mm(2), 140.1 mm(2) and 273.0 mm(2), respectively. Conclusions: It is concluded that the metho dology employed accurately recorded temperature changes at and around the dental implant site, and provided preliminary baseline data agains t which the cooling efficacy of different irrigant systems may be comp ared. Copyright (C) 1996 Elsevier Science Ltd.