Photobiomodulation in Dental Implant Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background/Objectives: Photobiomodulation (PBM) is proposed to enhance osseointegration, improve stability, reduce marginal bone loss, and alleviate pain in implant dentistry. Since clinical outcomes remain heterogeneous, this systematic review and meta-analysis evaluated PBM's effects as an adjunct to implant therapy, focusing on stability, peri-implant bone outcomes, and pain.

Methods

A comprehensive search of six databases and gray literature (June 2024-May 2025) followed PRISMA guidelines (PROSPERO: CRD420251041607). We included randomized controlled trials (RCTs) evaluating PBM against sham or no-PBM controls in adults. Risk of bias was assessed using RoB 2, and data were synthesized via random-effects meta-analyses with GRADE certainty assessments.

Results

Thirty-two RCTs (829 patients, 1278 implants) were included. Postoperative pain was consistently reduced by PBM (MD = -0.27; 95% CI -0.35 to -0.19). For stability, Periotest favored PBM (MD = -0.55; 95% CI -0.84 to -0.27), indicating a transient early improvement. Similarly, resonance frequency analysis (ISQ) demonstrated a statistically significant improvement favoring the PBM group (MD = 1.26; 95% CI 0.61 to 1.91, p < 0.001), indicating a statistically significant increase in early implant stability. Marginal bone loss showed a statistically significant but clinically small reduction favoring PBM (MD = -0.09 mm; 95% CI -0.16 to -0.01). For peri-implant bone density, time-stratified models showed that PBM promoted a robust, significant initial benefit in 3D CBCT Hounsfield Units at baseline (MD = 114.07 HU, p = 0.01; overall MD = 86.02 HU, p = 0.14), while conventional 2D radiographic grayscale measurements captured a modest but statistically significant overall benefit (MD = 9.82, p = 0.03), showing a positive long-term trend up to 6 months (MD = 24.19, p = 0.04).