Evaluating the Effects of Low-Level Laser Therapy (LLLT) on Surgical Wound Healing in Animal Models: A Scoping Review

Abstract

Background: Surgical site infections and impaired postoperative wound healing represent a substantial global burden, affecting millions of patients annually and driving significant clinical, economic, and antimicrobial-resistance consequences. Low-Level Laser Therapy (LLLT), also termed photobiomodulation (PBM), has attracted growing preclinical interest as a non-invasive adjunct to surgical wound management through its proposed effects on mitochondrial bioenergetics, collagen synthesis, inflammatory resolution, and angiogenesis. Despite a substantial body of experimental animal research, the full scope, parameter distribution, biological outcomes, and methodological characteristics of this literature have not been systematically mapped in a manner specific to surgically induced wound models. Objective: This scoping review aimed to map and synthesize the available preclinical experimental evidence on the effects of LLLT on surgically induced wound healing in animal models, characterize the range of laser parameters and dosimetric protocols employed, identify the biological and histological outcomes reported, and delineate evidence gaps and methodological limitations requiring prioritized investigation. Methods: The review was conducted in accordance with the Joanna Briggs Institute (JBI) scoping review framework and reported following the PRISMA extension for Scoping Reviews (PRISMA-ScR). A systematic search of PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar was conducted covering the period January 2000 to August 2025. Eligibility was defined using a Population, Concept, and Context (PCC) framework, restricted to original experimental animal studies investigating LLLT in surgical wound models with quantifiable biological, histological, or molecular outcomes. Data were charted using a standardized extraction form and synthesized through descriptive thematic analysis organized by wound type, laser parameter distribution, and outcome domain. Critical appraisal was not conducted, consistent with the exploratory mapping objective. Results: Sixteen studies meeting eligibility criteria were included, published between 2007 and 2025, predominantly from Brazil (31.3%) and Egypt (25.0%), with healthy rats (56.3%) and excisional wound models (56.3%) most frequently represented. Wavelengths ranged from 630 to 808 nm, with energy densities of 3–8 J/cm² most commonly employed. Wound closure or contraction was reported in 15 of 16 studies (93.8%), collagen synthesis or organization in 13 (81.3%), inflammatory markers in 10 (62.5%), and angiogenesis in 5 (31.3%). Incisional and sutured wound models, the most clinically representative surgical wound types, were addressed in only three studies combined. No included study assessed surgical site infection as an outcome, and no study conducted molecular or genetic analysis. Dosimetric reporting was incomplete in three studies, and blinding and randomization procedures were inconsistently described. Conclusion: The mapped preclinical evidence consistently associates LLLT with improved wound closure, collagen organization, inflammatory resolution, and angiogenesis across multiple animal species and wound contexts, supporting the biological plausibility of photobiomodulatory effects in surgical wound healing. However, the evidence base is characterized by geographic concentration, model-type asymmetry, incomplete dosimetric reporting, and critical gaps in infection-related, molecular, and biomechanical outcome domains. Standardized dosimetry protocols, infection-endpoint inclusion, molecular mechanistic studies, and rigorous clinical trials are needed to translate this experimental foundation into evidence-based postoperative care.