Heat generation during osteotomy performed with ultrasonic insert versus rotary instrument in bovine femur: ex vivo comparison.

Osteotomy procedures in dentistry are usually performed with drills, but piezosurgical instruments have also been used to improve surgical conditions for both the patient and the operator. This ex vivo study uses infrared thermography to analyze heat generation in osteotomies.

Aim: The aim of this study was to conduct an infrared thermographic comparison of the heat generated by an ultrasonic insert, either with or without an aerosol dispersion control device, in contrast to a conventional bur, during osteotomy procedures performed on bovine femur specimens.

Materials and method: Osteotomies were performed on nine bovine femur blocks, with each osteotomy consisting of a linear cut 12 mm long and 3 mm deep. Each block underwent a single cut from each instrument examined. The osteotomies were divided into three groups according to the instrument used: Group CARB, carbide bur #701; Group INS, #SFR4 ultrasonic insert coated with diamond-like carbon (DLC); and Group INS-S, #SFR4 ultrasonic insert coated with DLC in combination with an aerosol dispersion control device ("spray control"). All incisions were standardized using an automated device. Thermal variations (ΔT) were assessed using an infrared thermographic camera. The maximum (Tm) and minimum (T0) temperatures recorded were utilized to calculate ΔT, following the equation: ΔT = Tm - T0. Statistical analyses were conducted using Kruskal Wallis test and Dunn's test for multiple comparisons (p <0.05).

Results: : The T0 and Tm recorded for INS (21.5°C ± 0.7ºC and 23.2ºC ± 0.7ºC) and INS-S (20.8ºC ± 0.4ºC and 21.8ºC ± 0.4ºC) were significantly higher (p <0.05) than for CARB (14.9ºC ± 0.8ºC and 17.6ºC ± 1.1ºC, respectively). The observed ΔT for INS (1.7ºC ± 0.4ºC) and INS-S (1.0ºC ± 0.4) were significantly lower (p <0.05) than for CARB (2.7ºC ± 1.1ºC). No significant difference in ΔT was observed for the other comparisons.

Conclusions: INS and INS-S produced significantly higher temperatures than CARB. Use of the "spray control" device resulted in a reduction of the temperature variation observed for the piezoelectric insert.