Clinical outcomes of surgical laser interventions and adjunctive photobiomodulation in osseous crown lengthening: A systematic review

To synthesize the available clinical evidence on laser-based interventions in osseous crown-lengthening procedures, considering surgical laser techniques and adjunctive photobiomodulation separately. A systematic search of PubMed/MEDLINE, Scopus, ScienceDirect, and Web of Science was conducted from database inception to June 2025. We included clinical studies involving adults undergoing osseous crown lengthening with laser-assisted surgery or postoperative photobiomodulation. Three reviewers independently screened titles and abstracts, assessed potentially eligible full-text articles, and extracted data. Risk of bias was assessed at the outcome level using RoB 2 for randomized studies and ROBINS-I for the nonrandomized comparative study. Because of substantial clinical and methodological heterogeneity, we evaluated findings using a structured narrative synthesis rather than meta-analysis. We included five clinical studies published between 2021 and 2024. Three evaluated lasers used during the surgical procedure, while two evaluated adjunctive photobiomodulation following conventional surgery. Some studies reported reduced intraoperative bleeding and improved surgical visibility with surgical laser techniques, although they did not consistently assess these outcomes using standardized quantitative measures. Periodontal and gingival-margin outcomes were generally comparable with conventional procedures. Findings regarding postoperative pain were inconsistent, with benefits reported in some but not all studies. Across two small studies using different irradiation protocols, adjunctive photobiomodulation was associated with reduced early postoperative pain at selected assessment times; only one study reported lower analgesic consumption. Among the four randomized studies, one assessed result was judged to have a high overall risk of bias and three raised some concerns; none was judged to have a low overall risk of bias. The nonrandomized comparative study was judged to have a serious risk of bias. Some studies descriptively reported potential intraoperative advantages with surgical laser techniques, while adjunctive photobiomodulation may reduce early postoperative pain at selected assessment times. Given the small and heterogeneous evidence base and its methodological limitations, current evidence remains insufficient to establish superiority over conventional osseous crown-lengthening surgery or to identify an optimal laser protocol.Clinical trial number: not applicable.