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

N/AActive Not RecruitingNCT07061756

Rui He240 enrolled

Overview

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.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

240

Conditions

Periodontitis

Interventions

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.

NDPROCEDURE

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.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 80 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Aged 18-80 years * Minimum of 14 remaining natural teeth * Diagnosis of Stage III-IV periodontitis according to the 2018 World Workshop classification system * No periodontal treatment within the past 6 months * Willing to provide informed consent and participate in the study protocol Exclusion Criteria: * Presence of systemic conditions that may affect periodontal treatment outcomes (e.g., uncontrolled hypertension \[\>140/90 mmHg\], diabetes mellitus \[HbA1c \>7%\]) * Use of antibiotics or medications known to induce gingival enlargement (e.g., calcium channel blockers, phenytoin) within the past 3 months * Coagulation disorders or hematologic diseases * Active systemic infections * Pregnancy or lactation * Acute periodontal lesions * Inability to comply with study protocols

Outcomes

Primary Outcomes

Alpha diversity of subgingival microbiota

The higher the alpha diversity, the greater the species richness and evenness of the microbial community.