The use of thermal imaging to assess heat generation during dental implant bed preparation in the presence of a surgical guide with an incorporated coolant channel.

PURPOSE: This study evaluates the thermodynamic benefits of including an irrigation fluid channel in the design of surgical guides used for dental implant site drilling.

MATERIALS AND

METHODS

Two types of guides suitable for hosting artificial bone plates that mimic the mechanical properties of human alveolar bone were designed: a classical guide (CLA-a splint with a guiding cylinder) and a guide with an internal coolant channel (INT). They were fabricated from titanium powder by selective laser melting. Graduated drillings were performed using a pilot bur followed by two larger ones; infrared thermography was used to record the temperature of the drill upon exit and the peak temperature of the specimen right after the bur's retraction.

RESULTS

The rise in bone temperature (mean ± standard deviation) while drilling through the CLA (INT) guide was 13.2 ± 3.6 (9.0 ± 3.4)°C for Drill 1, 4.3 ± 1.0 (2.1 ± 1.0)°C for Drill 2, and 2.1 ± 0.6 (0.4 ± 0.5)°C for Drill 3; the differences were statistically significant (p < 0.0032). To characterize individual differences between pairs of drillings conducted with different guides, Bland-Altman analysis was performed for the most thermogenic step. The mean difference between temperature elevations recorded with CLA and INT was -5.8°C, whereas the limits of agreement were 2.9°C and -14.4°C. In 95% of the cases, INT displayed more efficient cooling than CLA.

CONCLUSION

Surgical guides with incorporated coolant channels ensure better heat removal than conventional guides. Further research is needed to assess bone overheating within a few hundred micrometers from the osteotomy edge.