Thermal Tissue Damage and Healing After Laser Excision of Benign Oral Soft‐Tissue Lesions: An Optical Coherence Tomography (OCT)‐Based Comparison of 980‐nm Diode and 1064‐nm Nanosecond‐Pulsed Nd:YAG Laser

Objectives: To compare a 980-nm diode laser and a 1064-nm nanosecond-pulsed Nd:YAG laser for the excision of benign oral soft-tissue lesions, evaluating thermal alteration, postoperative outcomes, and tissue morphology during healing by optical coherence tomography (OCT). Methods: Patients were randomly allocated to treatment with either a 980-nm diode laser (Group A) or a 1064-nm nanosecond-pulsed Nd:YAG laser (Group B). OCT was performed before surgery, immediately after excision, and at 2 and 4 weeks. Epithelial (EP) and lamina propria (LP) thicknesses were assessed, while postoperative pain and oral health-related quality of life were evaluated using VAS and OHIP-14. Thermal alteration at the surgical margins was quantified histologically. Results: A total of 50 patients were included, with 25 in each group. Both groups showed favorable postoperative outcomes, with generally mild pain and low analgesic consumption. OHIP-14 scores were descriptively lower in Group B, without statistically significant differences. Thermal alteration was significantly greater with the diode laser than with the 1064-nm nanosecond-pulsed Nd:YAG laser (494.48 +/- 156.97 mu m vs. 253.81 +/- 77.38 mu m; p < 0.001). At 4 weeks, OCT showed no significant differences in EP and LP thicknesses between groups, although both remained different from the healthy contralateral mucosa. Conclusions: Both laser modalities provided favorable clinical outcomes and specimens suitable for histopathological diagnosis. The 1064-nm nanosecond-pulsed Nd:YAG laser resulted in significantly lower thermal alteration than the 980-nm diode laser, while OCT showed comparable tissue morphology at 4 weeks. These findings suggest a potential advantage of the nanosecond-pulsed Nd:YAG laser when minimizing thermal damage is a priority.