NCT07061756

Nd:YAG Laser Effects on Subgingival Microbiota in Stage III-IV Periodontitis

Characteristics of Subgingival Microbiota in Patients With Stage III-IV Periodontitis in Response to Nd:YAG Laser-Assisted Therapy

• Status: Active Not Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 240 (estimated)
• Sponsor: Rui He · Academic / Other
• Sex: All
• Age: 18 Years – 80 Years
• Healthy volunteers: Accepted

Summary

This randomized controlled trial (RCT) aims to evaluate the clinical efficacy of Nd:YAG laser adjunctive therapy and its impact on the subgingival microbiome in patients with stage III-IV periodontitis. The study addresses two key questions: (1) Whether Nd:YAG laser combined with scaling and root planing (SRP) yields significantly greater improvements in periodontal parameters compared to SRP alone; and (2) How subgingival microbial dynamics correlate with therapeutic outcomes. Participants were randomized into two groups: the SRP group (mechanical debridement only) and the Nd group (mechanical debridement with Nd:YAG laser therapy). Clinical parameters-including probing depth (PD), clinical attachment level (CAL), and gingival index (GI)-were assessed at baseline and 3 months post-treatment. Subgingival plaque samples were analyzed via 16S rDNA sequencing to characterize microbial community shifts.

Conditions

• Periodontitis

Interventions

Type	Name	Description
PROCEDURE	SRP	Full-mouth scaling and root planing (SRP) was performed using an ultrasonic scaler (EMS AIR-FLOW MASTER PIEZON®) supplemented by Gracey curettes for subgingival instrumentation. All procedures were conducted under local anesthesia by a calibrated periodontist, with each quadrant treated for a minimum of 30 minutes. Patients received standardized oral hygiene instructions and were scheduled for a 3-month postoperative follow-up.
PROCEDURE	ND	In addition to the identical SRP protocol described above, adjunctive Nd:YAG laser therapy (Wiser Waterlase MD, Vista Dental) was applied immediately post-SRP. Laser parameters were set at 150 mJ/pulse, 20 Hz frequency with water (level 1) and air (level 3) coolant. The fiber optic tip (300 μm diameter) was moved in a continuous "Zig-zag" pattern along the root surface and pocket epithelium, maintaining 2-second irradiation per site at a 30° angle to the tooth axis. Standardized oral hygiene instructions and 3-month follow-up were similarly provided.

Timeline

• Start date: 2024-08-28
• Primary completion: 2025-03-20
• Completion: 2025-07-24
• First posted: 2025-07-11
• Last updated: 2025-07-11

Locations

1 site across 1 country: China