12 patients treated for Group 1 using a Nd-YAG laser on the left side of the maxilla. The procedure was performed under local anesthesia to ensure patient comfort and cooperation. The parameters for the Nd-YAG laser (Lightwalke, Fotona, Slovenia) that was utilized for this procedure were: center wavelength of 1064 nm, output power of 4 W, frequency equal to 25 Hz, Micro Short Pulse (MSP) mode, sapphire fiber of 300 micrometers in diameter, power density equal to 6229 W/cm2.

The right side was treated conventional using the scalpel. Clark's vestibuloplasty method was applied in all conventionally operated right sides of the patients

12 patients treated for Group 2 where a diode laser was utilized. for performing the left side of the maxilla. we utilized the Epic X TM laser from Biolase, with a center wavelength of 940 nm and a pre-initiated tip, in a contact, continuous mode, with an output energy of 3 W. Surgery with the laser tip began at the mucogingival junction with a horizontal movement directing the laser parallel to the bone, and thus slowly releasing the muscle fibers towards the new vestibule depth. The right side of the maxilla was performed by conventional surgery using Clark s method.

12 patients treated for Group 3 where an Er-YAG laser was utilized to treat the left side of the maxilla. The Er-YAG laser (Lightwalker, Fotona, Slovenia) was equipped with a H14 handpiece, characterized by the following parameters: center wavelength of 2940 nm, contact mode, long pulse, energy of 200 mJ, frequency equal to 20 Hz, power of 4 W, water 2, gas 2. The right side of the maxilla was performed by conventional surgery using Clark s method

For patients treated by Nd-YAG laser, the procedure was performed under local anesthesia . The parameters for the Nd-YAG laser are: center wavelength of 1064 nm, output power of 4 W, frequency equal to 25 Hz, Micro Short Pulse (MSP) mode, sapphire fiber of 300 micrometers in diameter, power density equal to 6229 W/cm2. Conventional vestibuloplasty was applied on the right side of the maxilla using Clark's method. A horizontal incision was performed at the mucogingival junction. The supraperiosteal dissection is performed and the muscles insertions were gradually dissected in an apical direction up to the desired vestibular depth. The mucosa of the inner side of the lip was undermined and the pedicled mucosal flap was secured to the periosteum at the new vestibule depth by using a 4-0 absorbable suture . The wound healed by second intention without any additional graft.

Pain and discomfort values were compared between the conventional surgery and the Nd:YAG laser, diode laser, and Er-YAG laser groups by using the Wilcoxon signed-rank test. The laser-treated sides have shown statistically significant reductions in both pain and discomfort scores at all considered timepoints (p < 0.05), as presented in the following.

Vestibular depth measurements were compared between the initial, the immediate postoperatively, and the 6-week postoperatively timepoints. Paired sample t-tests or Wilcoxon tests were utilized, depending on distribution, to evaluate changes within each technique (i.e., conventional and lasers).