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 μm vs. 253.81 ± 77.38 μm; 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.