Proposal of a prophylactic photobiomodulation protocol for chemotherapy-induced oral and oropharyngeal mucositis: a randomized clinical trial.

Photobiomodulation therapy (PBMT) is widely used in oncology settings, but lack of assessment standardization is the main barrier to optimization of clinical protocols. This study analyzed three PBMT protocols for preventing oral and oropharyngeal mucositis (OM) in patients undergoing chemotherapy (CT) and/or hematopoietic stem cell transplantation (HSCT). This is a preliminary randomized blind clinical trial. Group 1 received intraoral prophylactic PBMT, Group 2 received intraoral and oropharyngeal PBMT, and Group 3 received intraoral, oropharyngeal, and extraoral PBMT. The applications were from the first day of CT to day + 10. Clinicodemographic data, CT regimens, types of HSCT, hematological exams, occurrence/severity of OM, odynophagia, and OM-related opportunistic infections were assessed. Sixty participants (age range: 18-74 years) were included; 70% of them underwent CT and 30% HSCT. About 43.3% of patients had OM, while odynophagia was reported by 23.3%. Both Groups 1 and 2 revealed better results. Multivariate analysis showed that HSCT directly influenced the occurrence of OM. Individuals who had undergone allogeneic HSCT were 1.93 times more likely to develop OM (p < 0.001). Group 3 exhibited a higher frequency of OM, albeit of lower grades. This group consisted of half the population who had undergone HSCT, had the highest percentage of melphalan use, and had the lowest mean leukocyte count. The three proposed protocols were effective in preventing and reducing OM, with good tolerance and no reported adverse effects. PBMT is a safe and effective approach to OM prophylaxis in adults undergoing CT/HSCT.

Does photobiomodulation therapy improve the postoperative outcomes of tonsillectomy? A systematic review and meta-analysis.

Introduction: Postoperative management of patients undergoing tonsillectomy is challenging. Photobiomodulation therapy (PBMT) has emerged as a new tool providing therapeutic benefits. However, the contribution of PBMT to the postoperative outcomes of tonsillectomy is still undefined. This systematic review and meta-analysis evaluated the published literature addressing the effects of PBMT on post-tonsillectomy. Methods: Searches in Scopus, PubMed/MEDLINE, Embase, Web of Science, Cochrane Library, and grey literature were carried out for the identification of randomised controlled trials reported up to August/2021. The risk of bias with the Cochrane Collaboration tool and meta-analysis was performed. Outcomes were assessed with the Kaplan-Meier method and the log-rank test. Results: A total of 1183 articles were retrieved, of which only two were included for qualitative and quantitative analysis. The wavelengths were 685 nm and 980 nm with energy density set at 4 J/cm2. The mandibular angle and the surgical wound were the sites of laser irradiation. Individuals who had not undergone PBMT after tonsillectomy were more likely to report pain and odynophagia in the first 24 hours after surgery than individuals who had undergone PBMT after tonsillectomy (P<0.001). Children who received PBMT after tonsillectomy were equally affected by pain and odynophagia in the first seven days after surgery compared to children who had not undergone PBMT after tonsillectomy (P>0.05). However, both studies found a significant association of PBMT with reduced analgesic consumption. Conclusion: Although PBMT seems promising for the management of individuals undergoing tonsillectomy, a limited number of studies are available in the literature.

Prophylactic photobiomodulation therapy using 660 nm diode laser for oral mucositis in paediatric patients under chemotherapy: 5-year experience from a Brazilian referral service.

The use of photobiomodulation therapy (PBMT) in the prevention of oral mucositis (OM) in paediatric care has increased. In this article, we report data of paediatric oncology/haematopoietic stem cell transplantation (HSCT) patients treated with PBMT to prevent chemotherapy-induced OM. A retrospective study was conducted at a Brazilian referral service. Prophylactic PBMT was used in children and adolescents (≤ 17 years) following the protocol: InGaAIP, 660 nm, 100 mW, 2 J, 3.33 W/cm2, and 20 s per point. Demographic data and OM severity scores were assessed. A regression model tested the association between OM with prophylactic PBMT and antineoplastic therapy. A total of 148 individuals who had undergone 358 chemotherapy cycles were analysed. A higher occurrence of OM was observed in HSCT and osteosarcoma (OS) patients. Except for HSCT, OM was associated with methotrexate (MTX) use in all disease groups. PBMT significantly reduced OM severity in acute lymphoblastic leukaemia (ALL) and OS patients. OM grade was 3.16 and 5.45 times higher among individuals with ALL and OS, who had not undergone prophylactic PBMT compared with those who had undergone prophylactic PBMT (p < 0.001). PBMT prevented chemotherapy-induced OM. Individuals who used MTX and did not undergo prophylactic PBMT were at increased risk of OM.

Photobiomodulation effects on keratinocytes cultured in vitro: a critical review.

Photobiomodulation therapy (PBMT) has been widely used for the promotion of tissue repair. Despite these therapeutic benefits, in some cases, PBMT appears to be unsuccessful, and the strongest hypothesis is that this failure is due to inadequate light dosimetry and wavelengths. The objective of the present critical review was to evaluate the effects of PBMT on cultured keratinocytes using blue, red, or near-infrared light categorized into arbitrary ranges of energy density (0.1-5.0, 5.1-10.0, 10.1-15.0, and over 15.0 J/cm2). The electronic searches were conducted in PubMed, Web of Science, Scopus and LILACS databases, and included LASER or LED devices. A total of 55 articles evaluating the effects of PBMT on cell viability, proliferation, migration, and cytokine and growth factor production were included. Overall, the studies failed to provide detailed information about light dosimetry or detailed experimental conditions. The vast majority of the energy densities tested produced unmodified results regardless of the wavelength applied. However, it was possible to observe that red and near-infrared light had more stimulatory effects than blue light. In addition, for all parameters analyzed, favorable outcomes were mostly obtained in the range of 0.1-5.0 J/cm2. The less explored energy densities were within the 10.1-15.0 J/cm2 range. Energy densities above 15.0 J/cm2 were ineffective or tended to cause cell death. The heterogeneity of the data does not allow us to define a PBMT range setting protocol that would have beneficial effects on keratinocytes.

Optical parameters and hardness of two maxillofacial elastomers after immersion in different solutions of Brazilian green propolis extract.

STATEMENT OF PROBLEM: Maxillofacial elastomers undergo physical and mechanical degradation with disinfecting solutions. Solutions of Brazilian green propolis extract may be suitable alternatives for infection control of maxillofacial prostheses. However, their effects on the properties of the material are unknown. PURPOSE: The purpose of this in vitro study was to evaluate the effect of disinfection with solutions of Brazilian green propolis extract on the transmittance, translucency parameter, contrast ratio, and hardness of 2 maxillofacial elastomers (MDX4-4210 and MED-4014). MATERIAL AND METHODS: Fifty disk-shaped specimens (3×10 mm) of each elastomer were randomly and equally divided into 4 groups of disinfectant agents and 1 control group: 3 separate groups of 11% green propolis extracts including aqueous (PAQ), glycolic (PGL), and alcoholic (PAL), a 2% chlorhexidine gluconate (CHX) group, and the control group of distilled water. Specimens were subjected to disinfection by immersion 3 times a week for 60 days. Color differences (ΔE values) were calculated with CIELab and CIEDE2000 formulas. Optical parameters and Shore A hardness were determined at 2 time points: at baseline and after the period of specimen disinfection. Data were analyzed by parametric and nonparametric analysis of variance and by multiple-comparison tests (α=.05). RESULTS: The ΔE values of specimens immersed in 11% PAL were not clinically acceptable for either elastomer. Regarding translucency parameter and contrast ratio, the immersion in 11% PAL and 11% PGL resulted in greater opacity and lower translucency of the material. Mean Shore A hardness values were not statistically significantly different at baseline or after 60 days of immersion in the solutions. CONCLUSIONS: The solution of Brazilian green propolis extract tested showed changes in optical parameters. Elastomers immersed in 11% alcoholic green propolis extract showed clinically unacceptable color and translucency changes. All hardness values of the tested elastomers were clinically acceptable after immersion in all tested disinfectant groups.