Photobiomodulation therapy on chemo- and radiotherapy induced oral conditions: an umbrella review.

OBJECTIVES: Photobiomodulation (PBM) is a laser-based therapy used to promote tissue repair, reduce inflammation and pain, and has been extensively studied in chemo- and radiotherapy-induced oral mucositis (OM). This review examines the level of evidence of systematic reviews (SRs) that have investigated PBM in such cases of OM. MATERIALS AND METHODS: SRs evaluating PBM for both the treatment and prevention of OM in patients undergoing chemotherapy and/or radiotherapy and published before November 30, 2023, on PubMed, Cochrane, Embase, Web of Science, LILACS, TRIP and Open Grey databases were eligible for inclusion. We assessed the level of methodological and meta-analytic procedures. RESULTS: Of the 1201 SRs, 21 that met the inclusion criteria were included. The quality of evidence was assessed using the Assessing the Measurement Tool to Assess Systematic Reviews (AMSTAR2), and the majority was of critically low quality (n = 15, 71.4%) with only 28.5% of low quality. A total of 40 meta-analytic estimates were obtained and analyzed. Approximately 87.5% of the meta-analysis were significant (n = 33), but only one meta-analyses had a strength of "highly suggestive", while the rest were classified as "weak". When analyzing the overlap values, the covered area was 12.14% and the corrected covered area was 7.75%, indicating a moderate overlap. Only 4 SRs had a very high overlap and one had a high overlap. CONCLUSION: The efficacy of PBM in the treatment of chemotherapy-induced OM is supported by low to critically low quality SRs and meta-analysis of low strength. This review highlights important areas that need to be addressed in future research on this topic. REGISTRATION: CRD42023484013 (PROSPERO).

Malignant transformation rate of oral leukoplakia-systematic review.

OBJECTIVE: The aim of this study was to perform a systematic review of prevalence studies to determine the rate of malignant transformation of oral leukoplakia and assess the influence of demographic factors (age, gender, and geographic region) on the overall transformation rate. STUDY DESIGN: A search was conducted for publications until July 2019 in 4 electronic databases and peer-reviewed journals. A manual search was performed on the bibliographies of the collected articles, and the authors were contacted for additional information. This study was previously registered with the trial number CRD42019126909 and study quality assessed through established methods. The results were expressed by means of proportions or odds ratios with a 95% confidence interval. Meta-regression was undertaken to evaluate possible sources of heterogeneity, and funnel plot visual analysis was performed to assess publication bias. RESULTS: The 34 observational epidemiologic studies included reported data on 26,209 patients with oral leukoplakia from 18 different countries. Meta-analysis of 32 studies (23,489 patients) presented an estimated overall mean proportion of malignant transformation rate of 9.70% (7.80-11.70) (I2 = 98.66%; τ2 < 0.001; χ2 = 23.18; degrees of freedom [df] = 31). When comparing genders, the odds ratio favored males with 0.622 (0.468-0.826) (I2 = 29.77%; τ2 = 0.089; χ2 = 22.78; df = 16). CONCLUSIONS: Within the limitations of the included studies in this systematic review, the results suggest that the malignant transformation rate was dependent on demographic factors and follow-up time. Future studies should include the development of guidelines to standardize the methodology for long-term follow-up assessment, thus reducing the risk of bias.