Heat Generation during Dental Implant Bed Preparation Using Surgical Guides with and without Internal Irrigation Channels Evaluated on Standardized Models of the Alveolar Bone

Abstract

Dental implant bed preparation involves surgical drilling. Heat generated in this process can cause a temperature elevation beyond the bone damage limit (10 °C), affecting the osseointegration of the implant. Surgical templates ensure accurate implant placement, but they limit the access of the irrigation fluid. This study evaluated the hypothesis that surgical guides with internal cooling prevent bone heating more effectively than classical guides. To eliminate biological variability, this study was conducted on artificial bone pieces that mimic the bone density of the human mandible. We created a surgical template that incorporated four pairs of guides—one classical (CLA) and one with internal cooling (INT) in each pair. For each specimen, we randomly selected the type of surgical guide to start with and performed four osteotomies with a 2.7 mm-diameter drill; then, we widened each hole with a 3.3 mm drill and finalized it with a 3.7 mm drill. The temperature was recorded by thermocouples placed at 0.8 mm from the prospective edge of the final osteotomy. In 168 measurements (12 osteotomies on 14 specimens) conducted for each type of surgical guide, the mean temperature rise was 7.2 ± 4.9 °C (mean ± standard deviation) for CLA and 5.0 ± 3.8 °C for INT. The mean differences between temperature elevations were 1.5 °C, 2.1 °C, and 3.0 °C for the first, second, and third drill, and they were statistically significant: the p-values of Student’s t-test were 0.004, 0.01, and 0.001, respectively. Although the mean temperatures remained safe, temperature rises exceeded 10 °C in 23.8% (9.5%) of the osteotomies performed in the presence of CLA (INT). Taken together, our results suggest that surgical guides with internal cooling ensure a significant drop in the temperature rise caused by implant site drilling.