The Thermal and Histological Evaluation of Lingual Frenulum Incision Using Diode Lasers in an Experimental Model

Background/Objectives: In lingual frenectomy/frenotomy surgeries, thermal surgical instruments are commonly used because of their hemostatic effect, precise cutting, and lack of need for sutures. However, the effects of tissue heating on the biological repair process remain under investigation. This study aimed to evaluate the thermal and histological effects of a surgical lingual frenulum incisions performed with high-power diode lasers at 450 nm (blue) and 980 nm (infrared), compared with a surgical scissor incision (control group). Methods: The experimental project was conducted in two phases: first, an ex vivo experiment on porcine tongues using different surgical instruments, with different parameters, with thermal variations recorded using infrared thermography; and second, an in vivo phase using the instruments previously determined in the ex vivo phase. Results: Results demonstrated minimal tissue heating in the control group. There was a thermal elevation with the laser instruments, particularly with the 980 nm and 450 nm diode lasers; however, the 450 nm laser showed a high initial temperature increase, but exhibited faster tissue cooling. Thermal and histological analyses performed immediately after the procedure and on the seventh postoperative day showed clinically similar tissue repair across groups, with less disorganization of collagen fiber bundles on day seven in the group treated with the 450 nm laser. Conclusions: In conclusion, both diode lasers can be safely employed for lingual frenulum incision when appropriate parameters are used; however, further clinical studies are warranted to establish safe and effective parameters.