Histological Effects of Er:YAG Laser Irradiation with Snoring Handpiece in the Rat Soft Palate.

OBJECTIVE: The aim of this study was to assess the effects of laser irradiation with a novel snoring handpiece on the histological structures of the soft palate in a rat model.

BACKGROUND: Snoring is a common problem and studies have shown that 20-50% of the population is affected. An apnea-hypopnea index of <5/h without daytime somnolence is documented as simple snoring. No snoring treatment should ever be attempted until a sleep study has been completed to rule out sleep apnea.

METHODS: Twenty adult Wistar rats, weighing 200-250 g, were used in this study. Rats were randomized into two groups: experimental group (n = 10) and control group (n = 10). Laser energy was delivered in a horizontal direction to the surface of the soft palate of each rat in the experimental group for 2 min with an Er:YAG laser (LightWalker AT; Fotona) with snoring handpiece (PS04) in a noncontact mode (1.15 W, 2 Hz, 1.5 J/cm(2)). The animals were sacrificed after 24 h, 1 week, 3 weeks, or 5 weeks. The soft palate of each rat was removed by excisional biopsy. The specimens underwent histological examination. Contractions and fibrosis were reported as grading from 1+ to 3+, while edema and hyperemia were evaluated according to the absence (0) or presence (1) of any changes. Statistical analysis was done with the Mann-Whitney U and Spearman's rho tests.

RESULT: A noticeable contraction of the soft palate occurred immediately after laser application. Inflammatory changes were observed histologically at 3 weeks postoperatively. Keratinization appeared after the procedure in both groups and decreased gradually. Statistically, there was a strong correlation among inflammation and time and also keratinization and time (p < 0.05).

CONCLUSIONS: The present study indicates that Er:YAG laser irradiation with snoring handpiece (PS04) causes acute shrinkage of the mucosa. This contraction decreases gradually but is still present at the end of fifth week.