Low-Level Laser Therapy in the Prevention and Treatment of Chemotherapy-Induced Oral Mucositis in Young Patients

Photobiomodulation CME part II: Clinical applications in dermatology

Photobiomodulation (PBM) is an emerging treatment modality in dermatology with increasing office and home-based use. PBM is the use of various light sources in the red light (620-700 nm) and near-infrared (700-1440 nm) spectrum as a form of light therapy. PBM is often administered through low-level lasers or light-emitting diodes. Studies show that PBM can be used effectively to treat conditions secondary to cancer therapies, alopecia, ulcers, herpes simplex virus, acne, skin rejuvenation, wounds, and scars. PBM offers patients many benefits compared to other treatments. It is noninvasive, cost-effective, convenient for patients, and offers a favorable safety profile. PBM can be used as an alternative or adjuvant to other treatment modalities including pharmacotherapy. It is important for dermatologists to gain a better clinical understanding of PBM for in-office administration and to counsel patients on proper application for home-use devices to best manage safety and expectations as this technology develops. PBM wavelengths can induce varied biological effects in diverse skin types, races, and ethnicities; therefore, it is also important for dermatologists to properly counsel their skin of color patients who undergo PBM treatments. Future clinical trials are necessary to produce standardized recommendations across conditions and skin types.

Effect of photobiomodulation on inflammatory cytokines produced by HaCaT keratinocytes

Objective

to evaluate the effects of the red and near-infrared wavelength lasers in isolated and simultaneous way on the modulation of inflammatory cytokines produced by human keratinocytes (HaCaT) challenged by cytokines of human monocytes stimulated by lipopolysaccharide from Escherichia coli.

Design

HaCaT cells was previously exposed to the laser with wavelengths red (660 nm), near-infrared (808 nm). Then, HaCat cells were stimulated with the supernatant of lipopolysaccharide-challenged peripheral blood cells. The cytokines expressed by HaCat cells were measured using multiplex CBA assay.

Results

HaCaT cells increased the production of inflammatory cytokines when stimulated with infrared laser compared to the control group (IFN-α2, IFN-γ, TNF-α, MCP-1, IL-6, IL-8, IL-10, IL -12p70, IL -17A, IL-23, IL-33), the red laser group (IFN-γ and IL-23) and the group of two lasers used simultaneously (IFN-α2, IFN-γ, IL-6 and IL-8, IL-17A, IL-18 and IL-23) (p < 0.05). The red laser also stimulated an increase in the expression of IFN-α2 by HaCaT cells in relation to the control group (p < 0.05).

Conclusion

Infrared laser, with an energy density of 5 J/cm2, appear to be able to modulate inflammatory cytokines produced by HaCaT cells challenged by human monocyte cytokines.

Photobiomodulation therapy for the prevention of acute radiation dermatitis: a systematic review and meta-analysis

PURPOSE

Approximately 95% of patients undergoing radiotherapy (RT) experience radiation dermatitis (RD). Evidence has suggested that photobiomodulation therapy (PBMT) can stimulate skin renewal and minimize RD. The aim of the present paper was to investigate the efficacy of PBMT in RD prevention through a comprehensive literature review.

METHODS

A literature search of Ovid MEDLINE, Embase, and Cochrane databases was conducted from 1980 to March 2021 to identify RCT on the use of PBMT for RD prevention. Forest plots were developed using RevMan software to quantitatively compare data between studies.

RESULTS

Five papers were identified: four in breast and one in head and neck cancer patients. Patients receiving PBMT experienced less severe RD than the control groups after 40 Gray (Gy) of RT (grade 3 toxicity: Odds Ratio (OR): 0.57, 95% CI 0.14-2.22, p = 0.42) and at the end of RT (grade 0 + 1 vs. 2 + 3 toxicity: OR: 0.28, 95% CI 0.15-0.53, p < 0.0001). RT interruptions due to RD severity were more frequent in the control group (OR: 0.81, 95% CI 0.10-6.58, p = 0.85).

CONCLUSION

Preventive PBMT may be protective against the development of severe grades of RD and reduce the frequency of RT interruptions. Larger sample sizes and other cancer sites at-risk of RD should be evaluated in future studies to confirm the true efficacy of PBMT, also in preventing the onset of RD and to finalize a standardized protocol to optimize the technique. At present, starting PBMT when RT starts is recommendable, as well as performing 2 to 3 laser sessions weekly.

Photobiomodulation for Chemotherapy-Induced Oral Mucositis in Pediatric Patients

Oral mucositis (OM) is a common side effect in patients undergoing chemotherapy (CT), especially in children due to their rapid epithelial mitotic rate. It has been associated with a significant reduction in life quality since it leads to pain, an inadequate intake of nutrients, an increased risk of opportunistic infections, and interruptions of CT. Photobiomodulation (PMB) with low-level laser therapy (LLLT) has shown faster healing, reduction in pain, and the reduced use of analgesic compared to placebo groups. The purpose of this review is to analyze and compare the existing clinical trials and identify their shortcomings in hope to make future research easier. Using MeSH terms and keywords, the Embase, Medline, and PubMed databases we searched for the period of the last 5 years. We identified a total of 15 clinical trials, with a total of 929 pediatric patients analyzed in this review. We compared different light sources and other laser technique characteristics used in clinical trials such as wavelength, energy and power density, spot size, irradiation time, PBM protocol, and OM evaluation. The main findings show inconsistent laser parameter quotations, differences in the PBM protocol along with a laser application technique, and a lack of clinical trials. Based on that, more studies with a high methodological quality should be conducted in order to provide a unified PBM protocol suitable for the pediatric population.

Interventions for the Prevention of Oral Mucositis in Patients Receiving Cancer Treatment: Evidence from Randomised Controlled Trials

Oral mucositis is a common and most debilitating complication associated with cancer therapy. Despite the significant clinical and economic impact of this condition, there is little to offer to patients with oral mucositis, and the medications used in its management are generally only palliative. Given that mucositis is ultimately a predictable and, therefore, potentially preventable condition, in this study we appraised the scientific literature to evaluate effective methods of prevention that have been tested in randomised controlled trials (RCTs). Published high-level evidence shows that multiple preventative methods are potentially effective in the prevention of oral mucositis induced by radiotherapy, chemotherapy, or both. Anti-inflammatory medications (including benzydamine), growth factors and cytokines (including palifermin), cryotherapy, laser-and-light therapy, herbal medicines and supplements, and mucoprotective agents (including oral pilocarpine) showed some degree of efficacy in preventing/reducing the severity of mucositis with most anticancer treatments. Allopurinol was potentially effective in the prevention of radiotherapy-induced oral mucositis; antimicrobial mouthwash and erythropoietin mouthwash were associated with a lower risk of development of severe oral mucositis induced by chemotherapy. The results of our review may assist in highlighting the efficacy and testing the effectiveness of low-cost, safe preventative measures for oral mucositis in cancer patients.

Twenty-year analysis of photobiomodulation clinical studies for oral mucositis: a scoping review

OBJECTIVE

Our objective was to review the first 20 years of photobiomodulation (PBM) clinical studies for oral mucositis (OM) mitigation.

STUDY DESIGN

A scoping review screened controlled clinical studies. The PBM devices, protocols, and clinical outcomes were analyzed.

RESULTS

Seventy-five studies met the inclusion criteria. The first study dated from 1992, and the term "PBM" was first published in 2017. Public services, placebo-controlled randomized trials, and patients with head and neck chemoradiation were predominant among included studies. Prophylactic red intraoral laser protocols were mostly used. Comparing the outcomes of all protocols was unfeasible due to missing treatment parameters and nonhomogeneous measurements.

CONCLUSIONS

The main barrier to optimizing clinical protocols of PBM for OM was the lack of standardization in clinical studies. Although PBM use is now globally present in oncology settings and generally marked by good outcomes reported, additional randomized clinical trials with well-described methods are necessary.

Effects of Photobiomodulation on Oral Mucositis: Visualization and Analysis of Knowledge

This review article mapped and analyzed the most cited articles on the association of photobiomodulation (PBM) with oral mucositis (OM) and the evolution of clinical protocols in the area. A comprehensive search was performed on the Web of Science Core Collection (WoS-CC) database, leading to the extraction of information such as title, authors, abstract, journal name, number, average of citations, study design, year of publication, institutions, continents, countries, type of laser used, irradiated anatomical points, primary anti-cancer therapy, and laser parameters. Among those, clinical trials and literature reviews were the most common study designs. The main type of laser used was the InGaAlP diode, with a wavelength ranging from 630-660 nm, power going in 40-100 mW, and energy density ranging from 0.375-22 J/cm². As for the anatomical sites irradiated by PBM, the cheek mucosa, upper and lower lips, lateral tongue, and bottom of the mouth stood out. This analysis highlights an increasing interest in PBM as a supportive treatment in cases of OM, as well as the evolution of the technique, types of laser devices, and protocols used.

Photobiomodulation therapy in management of cancer therapy-induced side effects: WALT position paper 2022

Disclaimer

This article is based on recommendations from the 12th WALT Congress, Nice, October 3-6, 2018, and a follow-up review of the existing data and the clinical observations of an international multidisciplinary panel of clinicians and researchers with expertise in the area of supportive care in cancer and/or PBM clinical application and dosimetry. This article is informational in nature. As with all clinical materials, this paper should be used with a clear understanding that continued research and practice could result in new insights and recommendations. The review reflects the collective opinion and, as such, does not necessarily represent the opinion of any individual author. In no event shall the authors be liable for any decision made or action taken in reliance on the proposed protocols.

Objective

This position paper reviews the potential prophylactic and therapeutic effects of photobiomodulation (PBM) on side effects of cancer therapy, including chemotherapy (CT), radiation therapy (RT), and hematopoietic stem cell transplantation (HSCT).

Background

There is a considerable body of evidence supporting the efficacy of PBM for preventing oral mucositis (OM) in patients undergoing RT for head and neck cancer (HNC), CT, or HSCT. This could enhance patients’ quality of life, adherence to the prescribed cancer therapy, and treatment outcomes while reducing the cost of cancer care.

Methods

A literature review on PBM effectiveness and dosimetry considerations for managing certain complications of cancer therapy were conducted. A systematic review was conducted when numerous randomized controlled trials were available. Results were presented and discussed at an international consensus meeting at the World Association of photobiomoduLation Therapy (WALT) meeting in 2018 that included world expert oncologists, radiation oncologists, oral oncologists, and oral medicine professionals, physicists, engineers, and oncology researchers. The potential mechanism of action of PBM and evidence of PBM efficacy through reported outcomes for individual indications were assessed.

Results

There is a large body of evidence demonstrating the efficacy of PBM for preventing OM in certain cancer patient populations, as recently outlined by the Multinational Association for Supportive Care in Cancer/International Society of Oral Oncology (MASCC/ISOO). Building on these, the WALT group outlines evidence and prescribed PBM treatment parameters for prophylactic and therapeutic use in supportive care for radiodermatitis, dysphagia, xerostomia, dysgeusia, trismus, mucosal and bone necrosis, lymphedema, hand-foot syndrome, alopecia, oral and dermatologic chronic graft-versus-host disease, voice/speech alterations, peripheral neuropathy, and late fibrosis amongst cancer survivors.

Conclusions

There is robust evidence for using PBM to prevent and treat a broad range of complications in cancer care. Specific clinical practice guidelines or evidence-based expert consensus recommendations are provided. These recommendations are aimed at improving the clinical utilization of PBM therapy in supportive cancer care and promoting research in this field. It is anticipated these guidelines will be revised periodically.

Low-level laser therapy for oral mucositis in children with cancer

OBJECTIVE

To assess the efficacy of oral low-level laser therapy (LLLT) - also known as photobiomodulation - in the reduction of oral mucositis experienced by children and young people with cancer undergoing chemotherapy.

DESIGN

A systematic review to evaluate the efficacy of oral LLLT for oral mucositis in children with cancer and the safety of oral LLLT in any age with cancer (International Prospective Register of Systematic Reviews/PROSPERO registration: CRD42018099772). Multiple databases and grey literature were screened. Randomised controlled trials were considered for assessing efficacy, and all studies were considered for assessing safety. Primary outcomes included severity of oral mucositis, oral pain and adverse events. Where results were compatible, meta-analysis was performed using a random-effects model. A narrative synthesis considered other outcome measures.

RESULTS

14 studies (n>416 children) were included in the narrative synthesis of LLLT efficacy. 5 studies (n=380 children and young people) were included in the meta-analyses. Results demonstrate that LLLT may reduce the severity of oral mucositis and the level of oral pain, but further randomised controlled trials are needed to confirm or deny this. There is vast variation in different trial protocols. Insufficient blinding between LLLT or sham therapy/control led to a strong risk of performance bias. 75 studies (encompassing 2712 patients of all ages who had undergone LLLT) demonstrated minor and infrequent adverse reactions, but most studies had significant areas of weakness in quality.

CONCLUSION

LLLT appears to be a safe therapy, but further evidence is needed to assess its efficacy as a prevention or treatment tool for oral mucositis in children with cancer.

Is Low-level Laser Therapy a Candidate to Be a Good Alternative in the Treatment of Mucositis in Childhood Leukemia?

BACKGROUND AND AIM

Oral mucositis (OM) is a common side effect of systemic chemotherapy (CT) in cancer patients. The aim was to evaluate the effect of low-level laser therapy (LLLT) for the treatment of CT-induced OM children.

PATIENTS AND METHODS

The study was carried out in 40 pediatric patients 3 to 18 years of age, who were hospitalized for the diagnosis of leukemia and underwent CT between June 1, 2019, and December 31, 2019. They were randomly divided into 2 groups with 20 cases in each group. The LLLT group was treated with GaAlAs diode laser (l): 830 nm (infrared), power: 150 mW, dose: 4.5 J/cm2 and the control group underwent bicarbonate treatment. Patients received intervention for 3 days. The grade of OM was clinically assessed by the World Health Organization (WHO) Common Toxicity Criteria Scale. Visual Analog Scale was used on the same days with OM grade to evaluate the pain status.

RESULTS

While there was no significant difference between the groups in terms of OM grade at the beginning of the treatment and on the first, second, fourth, and 11th days of the treatment, the average OM grade of the LLLT group was found to be statistically significantly lower on the third, fifth, sixth, and seventh days of the treatment. The Visual Analog Scale score of the LLLT group was statistically significantly lower compared with the control group at all examinations starting from the first day of treatment (P<0.05).

CONCLUSION

In the treatment of oral OM that occurs in children after CT, both standard care and LLLT treatment improve the grade and pain of OM.

Chemotherapy drugs and inflammatory cytokines enhance matrix metalloproteinases expression by oral mucosa cells

OBJECTIVE

Oral mucositis (OM), the most common side effect of cancer therapy, is associated with pro-inflammatory cytokines and matrix metalloproteinases (MMPs) increased expression. Although there are approaches for OM management, none is infallible, thus, elucidation of molecular events related to OM etiopathogenesis may improve current therapeutic strategies. This study assessed the influence of pro-inflammatory cytokines and chemotherapy drugs on MMPs expression and synthesis by oral mucosa cells.

DESIGN

Human gingival fibroblasts (HGF) were exposed to different concentrations of methotrexate (MTX) and 5-fluorouracil (5-FU); subsequentially, cell viability, nitric oxide and interleukin(IL)-6 production were evaluated to select the concentration of these drugs that could stimulate inflammatory phenotype without cytotoxic effects. Then, HGF and primary gingival keratinocytes (PGK) were subjected to different stimuli: culture medium (negative control), tumor necrosis factor-alpha (TNF-α - positive control), IL-6, IL-8, MTX, and 5-FU for 3, 6, 12, and 24 h. Next, gene expression and synthesis of MMP-2 and MMP-9 by HGF and MMP-3 by PGK were assessed.

RESULTS

At 6 h, MMP-2 synthesis increased 60 % after exposure to TNF-α and MTX, 40 % after IL-6, and 15 % after IL-8. At 12 h, MMP-9 synthesis increased 15 % after exposure to TNF-α, while MMP-3 synthesis increased 30 % after TNF-α, and 10 % after IL-8. TNF-α-treated groups presented increased gene expression of all MMPs evaluated. IL-8 and 5-FU increased MMP-2 and MMP-3 expression, while IL-6 and MTX augmented MMP-2 expression.

CONCLUSIONS

The chemotherapy drugs and cytokines investigated up-regulated MMPs expression by oral mucosa cells, which may lead to OM establishment and severity.

Adherence of head and neck cancer patients to laser photobiomodulation in a public health service: Pilot study

OBJECTIVE

The aim of this study was to evaluate the adherence of patients with head and neck cancer who underwent radiotherapy or radio-chemotherapy combined to the preventive laser photobiomodulation protocol in a public health service.

MATERIALS AND METHODS

This was a cross-sectional study, whose population sample included patients with malignant head and neck neoplasms. Thirty head and neck cancer patients undergoing cancer treatment, were examined and interviewed through a record of signs and symptoms of oral mucositis (OM) and adherence to the preventive laser photobiomodulation protocol, that began in the first session of radiotherapy, and included the laser application three times a week during the 3-week period. The collected data were documented, and the descriptive and inferential statistics were performed with a significance level of p < 0.05.

RESULTS

It was observed that 66.6% of patients developed OM. There was a predominance of degrees I and II, with 36.8% and 31.6%, respectively. A total of fifteen patients (50%) missed one or more laser photobiomodulation sessions. A positive association was found between patients who missed at least two laser photobiomodulation sessions with the development of OM degrees III (p < 0.05).

CONCLUSIONS

There was moderate adherence of patients with head and neck cancer to the laser photobiomodulation protocol and the development of more severe degrees of OM was related to individuals that didn't attend scheduled sessions.

Patient Centeredness in Orthognathic Surgery

Patient centeredness in planning treatment and research has become paramount. The goal of this report was to describe a complex case in which untreated chronic pain was not properly addressed to reflect on the need to establish alternative protocols for controlling chronic orofacial pain. When a female underwent orthognathic surgery to correct her occlusion, she not only ended up with a worse occlusion, she developed chronic orofacial pain that could not be treated by opioids and only improved after the use of neuropathic medication, and finally disappeared after the use of low-level laser therapy. There is a need to incorporate alternative nonpharmacological approaches to manage chronic pain. Further, what the patient’s goals are for their treatments should be given priority in case of elective procedures.

Comparative analysis of the light parameters of red and near-infrared diode lasers to induce photobiomodulation on fibroblasts and keratinocytes: An in vitro study

BACKGROUND

Photobiomodulation (PBM) depends on the use of non-ionizing light energy to trigger photochemical changes, particularly in light-sensitive mitochondrial structures. It triggers proliferation and the metabolic activity of the cells, primarily by utilizing the energy from the near-infrared to the red wavelength of the light.

PURPOSE

This in vitro study has analyzed comparatively the most appropriate energy doses and wavelengths to induce PBM on keratinocytes and fibroblasts for the accelerated wound healing process.

METHODS

1, 3, and 5 J/cm² energy densities of 655 and 808-nm diode lasers were used to promote cell proliferation and wound healing process. Scratch assay and MTT analysis were performed on keratinocytes and fibroblasts for wound closure and cell proliferation after the triple light applications, respectively.

RESULTS

655-nm of wavelength was more successful on keratinocytes to induce wound healing and cell proliferation, whereas 808-nm of wavelength was so effective on fibroblasts to heal the wounds totally and it induced cell proliferation almost 3 times compared to the untreated control group.

CONCLUSION

This study revealed that PBM with 655 and 808 nm of wavelengths was effective to speed up the wound healing process at specific energy densities. In general 808-nm of wavelength was more successful. However, the proper wavelength and the energy density may differ according to the cell type. Thus, every light parameter should be chosen properly to obtain better outcomes during PBM applications.

Effects of 660 nm and 810 nm Low-Power Diode Laser on Proliferation and Invasion of Oral Cancer Cells in Cell Culture Media

In the present study, the effects of 660 and 810 nm diode laser on the proliferation and invasion of cancer cells were investigated. Sixteen plates of oral cancer cells originated from tongue SCC were irradiated with diode laser at 660 nm (40 and 80 mW) and 810 nm (100 and 200 mW) with the energy density of 4 J cm^-2 . One plate received no irradiation (the control). Irradiation was performed at four times (0, 24, 72 and 168 h). Cell proliferation was measured by MTT assay. The Ki67 and vascular endothelial growth factor (VEGF) markers were examined by real-time polymerase chain reaction (RT-PCR). Cyclin D1, E-cadherin, β-catenin and matrix metalloproteinase-9 (MMP-9; flow cytometry) were also evaluated. Proliferation was lower in the irradiated groups. This result was significant for all groups at 24 h. The percentages of cyclin D1 and MMP-9 were higher in 810 nm groups, β-catenin and E-cadherin were higher in 660 nm groups, VEGF marker was significantly lower in 810 nm/200 mW group, and Ki67 marker has no difference between the groups. According to the results of this study, laser irradiation at 0 and 24 h resulted in a significant inhibitory effect on cell proliferation especially in 660 nm/80 mW and 810 nm/200 mW. Further studies are needed in this respect.

Photobiomodulation and Oral Mucositis: A Systematic Review

Oral mucositis (OM) is a debilitating complication of chemotherapy, and head and neck radiotherapy. In an effort to offer the best possible advice within the limitations of published research, a systematic review with an extended discussion and commentary on dosimetry and dose delivery is presented. Using keywords as listed, Pubmed, Google Scholar and Cochrane databases were searched during a period extending from 1995 to 2019. A total of 782 abstracts were identified. A total of 50 papers were analysed, and of these, 29 satisfied criteria required for systematic review in accordance with an optimized PRISMA statement. Clinical outcome as reported was subject to analysis with respect to time of intervention, incidence and severity of oral mucositis, and pain amelioration, and a comprehensive combined univariate and multivariate statistical analysis of the methods employed was performed. Recommendations are made with respect to the timing of the intervention. Moreover, there is an extended discussion available on the treatment care rationale of photobiomodulation (PBM), and its adjunctive association with OM. In conclusion, early prophylactic application offers clear advantages in clinical management. The many studies and associated variables and covariables assessed here revealed a choice of delivery techniques, associated wavelengths and many further indices to consider with regard to the accomplishment of optical parameters. It is therefore our recommendation that clinicians use PBM as a therapy with a full and proper understanding and training in order to optimise the clinical effects achievable.

Optimization of Photobiomodulation Protocol for Chemotherapy-Induced Mucositis in Pediatric Patients

Objective: To determine optimal settings of a specific diode laser for reducing the severity of oral mucositis (OM) in pediatric patients. Background: Photobiomodulation (PBM) has been reported to reduce the severity of chemotherapy-induced OM. Treatment parameters for PBM are difficult to determine due to different reports in the literature. Materials and methods: Patients with OM graded WHO 3 or 4 were randomly assigned to three groups with different laser settings (group A: power 250 mW, the energy density 8.8 and 15.5 J/cm² for WHO grade 3 and 4, respectively; group B: power 500 mW, energy density as in group A; group C: power 250 mW, energy density was half of groups A and B). PBM was performed on all lesion areas. The mean number of PBM sessions to a decrease from WHO 3 or 4 to WHO 2, 1, or 0 was calculated for each patient. Multiple linear regression was used to determine whether the test groups differed in the mean number of sessions to a decrease of OM. Results: The mean number of PBM sessions to reduce from severe mucositis to mild or no mucositis was 3.8 [standard deviation (SD) = 3.5] in group A, 4.4 (SD = 2.3) in group B, and 4.0 (SD = 2.7) in group C. The differences in the number of PBM sessions for OM severity decrease were not statistically significantly different among the three study groups. Conclusions: Because of the lack of statistically significant differences between the groups, more patient practical laser parameters could be applied, that is, a shorter irradiation time.

Low-level laser therapy in the prevention and treatment of oral mucositis: a systematic review and meta-analysis

OBJECTIVE

The aim of this study was to determine whether prophylactic and therapeutic low-level laser therapy (LLLT), compared with placebo or no therapy, reduced the risk of severe oral mucositis (OM) in patients receiving chemotherapy or radiotherapy.

STUDY DESIGN

We searched for articles published on randomized controlled trials (RCTs) in the databases MEDLINE, EMBASE, Cochrane Library, Cochrane Central Register of Controlled Trials, Web of Science, and Clinical Trials, until December 2018. RCTs were filtered on the basis of eligibility criteria, and data were analyzed by using R software 3.5.2.

RESULTS

Overall, 30 studies were included in the meta-analysis. Prophylactic LLLT reduced the overall risk of severe OM (relative risk [RR] = 0.40; 95% confidence interval [CI]: 0.28-0.57; P < .01). Therapeutic LLLT substantially reduced the duration of severe OM (P < .01). LLLT also reduced the overall mean grade of OM, overall incidence of severe pain, mean score of pain, and incidence of severe OM, at the most anticipated time.

CONCLUSIONS

Prophylactic and therapeutic LLLT can reduce the risk of severe OM in patients receiving chemotherapy or radiotherapy.

The Effects of Photobiomodulation on Vocal Fold Wound Healing: In Vivo and In Vitro Studies

Background: Photobiomodulation (PBM) is increasingly used in dermatology and dentistry due to its benefit of promoting wound healing and relieving pain; however, there is no corresponding research report on the application of PBM to vocal fold wound healing. Objective: To assess the potential wound-healing effects of PBM on the vocal folds via in vivo and in vitro experiments. Materials and methods: In in vitro study, vocal fold fibroblasts (VFFs) were irradiated under a diode laser with wavelength of 635 nm at energy density of 8 J/cm². The Cell Counting Kit-8 (CCK-8) assay was used to study the viability of VFFs, and the gene expressions of COL1A2, COL3A1, IL-6, HAS2, and COX-2 were investigated by real-time polymerase chain reaction (RT-PCR). In in vivo study, 15 rabbits were used. Lamina propria of the left vocal folds of 12 rabbits was unilaterally stripped, and 6 of them were treated with PBM. The remaining three rabbits served as normal controls. After 3 months, all animals were sacrificed to obtain histological results. We used laryngoscope to record images of the healing phase. Results: Irradiation with energy density of 8 J/cm² resulted in a 2.8% increase in cell proliferation (p < 0.05). However, the difference between the experimental and the control group became larger after 48 and 72 h of subsequent irradiation. RT-PCR results showed that the expression of COL1A2, COL3A1, and HAS2 was higher, and the expression of IL-6 and COX-2 was lower. Histological examination showed that, compared with the injury group, hyaluronic acid (HA) increased significantly, collagen deposition decreased, and the configuration of collagen was more organized after PBM treatment. Conclusions: PBM can inhibit inflammatory reaction and promote the secretion of HA to decrease the deposition of collagen and regenerate vocal fold tissue without scar.

A brief literature review and own clinical experience in prophylaxis of oral mucositis in children using low level laser therapy

OBJECTIVE

The article describes the experience of clinical application of low level laser therapy in pediatric oncology for the prevention and treatment of chemotherapy complications such as oral mucositis.

BACKGROUND

For this purpose, for the first time in the world non-invasive laser blood illumination is used on the sinocarotid zone (on the projection of the common carotid artery symmetrically) and popliteal fossa in order to stimulate the phagocytic activity of leukocytes.

METHODS

25 children with different oncological diseases were given non-invasive laser blood illumination treatment (904 nm, pulse mode, 100 ns, 50-150 Hz, 5-7 W, 4 cm², 1-2 minutes daily per each procedure) 1-3 days before the beginning of chemotherapy. For the objectification of the results of treatment, the phagocytic activity of leukocytes was evaluated.

RESULTS

None of the children who underwent low level laser therapy course had any complications and no cases of oral mucositis developed.

CONCLUSIONS

Clinical experience has shown high efficacy and safety of low level laser therapy aimed at preventing the development of complications of chemotherapy, primarily oral mucositis, and stimulating the phagocytic activity of leukocytes.

Low-level laser therapy in patients with Burning Mouth Syndrome: A double-blind, randomized, controlled clinical trial

Background

Evaluate the effect of LLLT in the treatment of burning mouth syndrome (BMS).

Material and Methods

Twenty-one BMS patients were randomly assigned to two groups: 12 in the laser group (LG) and 9 in the control group (CG). Patients in the LG underwent 2-week sessions of LLLT for 4 weeks. The spot tip area of this tool is 0.088cm2, semi-conductor GaAlAs, with a wavelength of 808nm ±5nm (infrared), 200 mW output power, 1.97W/cm2 of power density, 3 J energy per point and application time 15 seconds per point. LLLT was applied punctually, in continuous emissions, on each of the sites where there was a symptom. Symptoms were evaluated with a visual analogue scale (VAS) and patient psychological profiles were assessed using the Hospital Anxiety-Depression Scale. No side effects were recorded. Statistical analysis was carried out via ANOVA and logistic regression analysis.

Results

The initial VAS score mean was 8.9 for the LG and 8.3 for the CG (p >0.05). After the eighth session the VAS score was 5.5 and 5.8 respectively, and at two months it was 4.7 and 5.1 respectively. Improvement variables were established by dichotomizing the pain scales. We obtained levels of significance for the improvement variable for the LG at the two-month follow-up (p=0.0038) and for the univariate analysis of the treatment. The improvement was marginally significant in the multivariant analysis of: dry mouth, dysgeusia, pain and the treatment (p=0.0538).

Conclusions

LLLT may be an alternative treatment for the relief of oral burning in patients with BMS. Key words:Burning mouth syndrome, oral pain, laser dentistry, laser therapy, low intensity laser therapy.

Wound-healing effects of 635-nm low-level laser therapy on primary human vocal fold epithelial cells: an in vitro study

Low-level laser therapy (LLLT) has been promoted for its beneficial effects on tissue healing and pain relief for skin and oral applications. However, there is no corresponding literature reporting on vocal fold wound healing. Our purpose was to assess the potential wound-healing effects of LLLT on primary human vocal fold epithelial cells (VFECs). In this study, normal vocal fold tissue was obtained from a 58-year-old male patient who was diagnosed with postcricoid carcinoma without involvement of the vocal folds and underwent total laryngectomy. Primary VFECs were then cultured. Cells were irradiated at a wavelength of 635 nm with fluences of 1, 4, 8, 12, 16, and 20 J/cm² (50 mW/cm²), which correspond to irradiation times of 20, 80, 160, 240, 320, and 400 s, respectively. Cell viability of VFECs in response to varying doses of LLLT was investigated by the Cell Counting Kit-8 (CCK-8) method. The most effective irradiation dose was selected to evaluate the cell migration capacity by using the scratch wound-healing assay. Real-time polymerase chain reaction (RT-PCR) was used to detect the gene expression of TGF-β1, TGF-β3, EGF, IL-6, and IL-10. Irradiation with doses of 8 J/cm² resulted in 4% increases in cell proliferation differing significantly from the control group (p < 0.05). With subsequent doses at 48 and 72 h after irradiation, the differences between the experimental and the control groups became greater, up to 9.8% (p < 0.001) and 19.5% (p < 0.001), respectively. It also increased cell migration and the expression of some genes, such as EGF, TGF-β1, TGF-β3, and IL-10, involved in the tissue healing process. This study concludes that LLLT at the preset parameters was capable of stimulating the proliferation and migration of human vocal fold epithelial cells in culture as well as increase the expression of some genes involved in tissue healing process. Additionally, successive laser treatments at 24 h intervals have an additive beneficial effect on the healing of injured tissues.

Evaluation of Oral Mucositis Occurrence in Oncologic Patients under Antineoplastic Therapy Submitted to the Low-Level Laser Coadjuvant Therapy

Low-level laser therapy has been widely used in treating many conditions, including oral mucositis. The purpose of this study was to evaluate the occurrence of oral mucositis in patients undergoing antineoplastic therapy submitted to preventive and therapeutic treatment with low-level laser therapy. This cross-sectional study was carried out with 51 children and adolescents of both sexes with malignant neoplasias who developed oral mucositis and underwent low-level laser therapy. Data were collected on sex, age, type and degree of neoplasia, region affected, and remission time. 64.7% of the patients were male and were between 3 and 6 years of age (39.2%). Acute lymphoid leukemia was the most frequent neoplasm (37.3%). Regarding the maximum oral mucositis, grade 2 (41.2%) was predominant, with jugal mucosa (29.9%) and tongue (17.7%) being the most affected regions. The majority of cases presented lesion remission time between 4 and 7 days (44.0%). Most patients were young, male, and diagnosed with acute lymphoid leukemia. Predominance of grade 2 oral mucositis was observed, with jugal mucosa and tongue being the most affected regions, with the majority of cases presenting lesion remission time between 4 and 7 days. Low-level laser therapy has been shown to be an essential therapy in the prevention and treatment of these lesions, since it is a non-invasive and low-cost method.

Guide for health professionals addressing oral care for individuals in oncological treatment based on scientific evidence

OBJECTIVE

Oncological treatment can cause changes in the oral cavity compromising oral functions. The aim of the study was, based on a systematic review, to draft a guide directed at the team of health professionals involved in the oral care of oncological patients.

METHODS

A systematic search of the literature was performed for articles published between 2000 and April 2017. Searches were made of electronic databases and hand search. The inclusion criteria were systematic reviews of randomized clinical trials (RCTs) and RCTs published in English, involving pediatric and adult oncological patients and focused on the prevention and treatment of oral complications as well as studies addressing the maintenance of oral health. Among the 1237 studies identified, 129 were pre-selected and 54 were selected to form the basis for the clinical guide.

RESULTS

The studies analyzed stress the need for oral assessments as well as preventive and curative actions prior to oncological treatment. To minimize the severity of oral problems, the studies emphasize daily oral care, the treatment of xerostomia with saliva substitute and hydration, and low-level laser therapy, nystatin, acyclovir, respectively, for the prevention and treatment of oral mucositis, oral candidiasis, and infection by herpes simplex virus. Thus, the guide produced addresses oral assessments and professional and home care before, during, and after oncological treatment.

CONCLUSION

The guide drafted has the function of assisting health professionals involved in the oral care of patients with cancer, enabling the prevention or treatment of oral complications stemming from oncological treatment.

A systematic review and meta-analysis of the effect of low-level laser therapy (LLLT) on chemotherapy-induced oral mucositis in pediatric and young patients

Oral mucositis is one of the most frequent complications after chemotherapy, occurring in approximately 52 to 80% of children receiving treatment for cancer. Recently, it has been suggested that the use of low-energy laser could reduce the grade of oral mucositis and alleviate the symptoms. In 2014, Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology has recommended low-level laser therapy in prevention of mucositis for hematopoietic stem cell transplantation patients because of its beneficial effects in majority of recent studies. However, the recommendation was made for adult patients, not pediatric patients. Data about the effect of low-level laser therapy in pediatric patients is limited. This study aims to synthesize the available clinical evidences on the effects of low-level laser therapy (LLLT) in the prevention and treatment of chemotherapy-induced oral mucositis (OM). A meta-analysis was performed using trials identified through the Cochrane Central Register of Controlled Trials, Embase, MEDLINE, Web of Science, China Biology Medicine (CBM), Wanfang Database, and China National Knowledge Infrastructure (CNKI). Data on occurrence, duration, and severity of oral mucositis were collected. All randomized controlled studies and clinical controlled studies comparing LLLT to routine qualified prevention or treatment during or after chemotherapy were critically appraised and analyzed. We found 8 qualified clinical trials with a total of 373 pediatric patients; the methodological quality was acceptable. After prophylactic LLLT, the odds ratio for developing OM was significantly lower compared with placebo(OR = 0.50, 95% CI 0.29 to 0.87, P = 0.01), the odds ratio for developing grade III OM or worse was statistically significantly lower compared with placebo (OR = 0.30, 95% CI (0.10, 0.90), P = 0.03), and the OM severity was statistically significantly lower compared with placebo (SMD = - 0.56, 95% CI (- 0.98, - 0.14), P = 0.009). For therapeutic LLLT, the OM severity was significantly reduced compared to routine care (SMD = - 1.18, 95% CI (- 1.52, - 0.84), P < 0.00001). Oral pain was also reduced after LLLT over routine care (MD = - 0.73, 95% CI (- 1.36, - 0.11), P = 0.02).

CONCLUSION

Prophylactic LLLT reduces mucositis and severe mucositis and decreases the average severity of oral mucositis in pediatric and young patients with cancer. Therapeutic LLLT also reduces the average severity of oral mucositis and oral pain. Further research should investigate the optimal parameter of LLLT in pediatric and young patients, and studies with higher methodological quality should be performed. What is known: • Low-level laser therapy (LLLT) was recommended by Multinational Association of Supportive Care in Cancer/International Society of Oral Oncology; however, evidences about LLLT on oral mucositis in pediatric and young patients were insufficient and lack supportive synthesized data. • Recently, there have been several new RCTs or CCTs for pediatric patients or young adults. What is new: • Prophylactic LLLT reduces the occurrence of mucositis and severe mucositis and decreases the average severity of oral mucositis in pediatric and young patients. • Therapeutic LLLT reduces the average severity of oral mucositis and oral pain.

Dosimetric study of photobiomodulation therapy in 5-FU-induced oral mucositis in hamsters

Oral mucositis (OM) is a debilitating consequence of cancer treatment that could be treated with photobiomodulation therapy (PBMT); however, there is no consensus about its dosimetric parameters for OM healing. The aim of this study was to compare different PBMT protocols on OM treatment, through clinical and histological analysis. Thirty hamsters were used, in an induced model of OM by 5-fluorouracil (5-FU) and superficial scratching, in seven days of follow-up. The animals were divided into five groups: control (C), which received only anesthesia and chemotherapeutic vehicle; chemotherapy (Ch), which received anesthesia, 5-FU, and scratches; laser 1 (L1), the same as Ch group, PBMT 6 ?? J / c m 2 and 0.24 J (one point); laser 2 (L2), the same as Ch group, PBMT 25 ?? J / c m 2 and 1 J (one point); and laser 3 (L3), the same as Ch group, PBMT 4 points of 0.24 J and 6 ?? J / c m 2 each. The laser used has ? = 660 ?? nm , 0.04 ?? c m 2 of spot area, and 40 mW. The best PBMT protocol to maintain lowest OM levels compared to Ch group was L1, followed by L2 and L3. Our results suggest that the application mode of PBMT and the energy delivered per area could interfere with the OM healing.

Evaluation effect of low level Helium-Neon laser and Iranian propolis extract on Collagen Type I gene expression by human gingival fibroblasts: an in vitro study

BACK GROUND AND AIM

production of collagen by fibroblast cells is a key component in wound healing. Several studies have shown that low level laser therapy (LLLT) and propolis extract stimulate collagen Type I production. The aim of this study is to evaluation the combined effect of LLL helium neon (632.8 nm) and Iranian propolis extract on collagen Type I gene expression by human gingival fibroblasts (HGF3-PI 53).

METHODS AND MATERIALS

Human gingival fibroblasts after culturing divided into six experimental groups: G1-control group, which received no irradiation and propolis extract, G2-irradiated at1.5 J/cm², G3-irradiated at 0.15 J/cm², G4-recived extract of propolis, G5- combined extract of propolis and 1.5 J/cm² laser irradiation and G6- combined extract of propolis and 0.15 J/cm² laser irradiation. The experiments were conducted in triplicate. After 24 hour, the total RNA was extracted and cDNA synthesis was performed. Type I collagen mRNA expression was determined with real time PCR.

RESULTS

The obtained results illustrated a statistically significant difference between G3 (0.15 J/cm²) and G1 (control group) in levels of collagen Type I messenger RNA (mRNA) expression (p<0.05). The irradiated cells showed a 1.4 times increase in mRNA expression of the collagen Type I gene. Expression of this gene decreases in other groups that this difference was statistically significant.

CONCLUSION

LLLT in different dosage and propolis extract may result in decreased or increased collagen type I gene expression. However this effect should be investigated in clinical studies.

Treatment of oral mucositis due to chemotherapy

INTRODUCTION

The management of oral mucositis is a challenge, due to its complex biological nature. Over the last 10 years, different strategies have been developed for the management of oral mucositis caused by chemotherapy in cancer patients.

MATERIAL AND METHODS

An exhaustive search was made of the PubMed-Medline, Cochrane Library and Scopus databases, crossing the key words "oral mucositis", "prevention" and "treatment" with the terms "chemotherapy" and "radiotherapy" by means of the boolean operators "AND" and "NOT". A total of 268 articles were obtained, of which 96 met the inclusion criteria.

RESULTS

Several interventions for the prevention of oral mucositis, such as oral hygiene protocols, amifostine, benzidamine, calcium phosphate, cryotherapy and iseganan, among others, were found to yield only limited benefits. Other studies have reported a decrease in the appearance and severity of mucositis with the use of cytoprotectors (sucralfate, oral glutamine, hyaluronic acid), growth factors, topical polyvinylpyrrolidone, and low power laser irradiation.

CONCLUSIONS

Very few interventions of confirmed efficacy are available for the management of oral mucositis due to chemotherapy. However, according to the reviewed literature, the use of palifermin, cryotherapy and low power laser offers benefits, reducing the incidence and severity of oral mucositis - though further studies are needed to confirm the results obtained.

KEY WORDS

Chemotherapy-Induced Oral Mucositis Treatment.

Efficacy of low-level laser therapy for the treatment of burning mouth syndrome: a randomized, controlled trial

The aim of the present study was to assess the effect of low-level laser therapy (LLLT) in the treatment of burning mouth syndrome (BMS). A diode laser was used in 78 BMS patients who were randomly assigned into four groups: IR1W, n = 20 (830 nm, 100 mW, 5 J, 176 J/cm2, 50 s, LLLT weekly sessions, 10 sessions); IR3W, n = 20 (830 nm, 100 mW, 5 J, 176 J/cm2, 50 s, three LLLT weekly sessions, 9 sessions); red laser, n = 19 (685 nm, 35 mW, 2 J, 72 J/cm2, 58 s, three LLLT weekly sessions, 9 sessions); and control-group (CG), n = 19. Symptoms were assessed at the end of the treatment and eight weeks later; quality of life related to oral health was assessed using the Oral Health Impact Profile (OHIP-14). Statistical analysis was carried out using repeated measures analysis of variance followed by the posthoc Tukey test. There was significant reduction of the symptoms in all groups at the end of the treatment, which was maintained in the follow-up. The scores of the IR1W and IR3W laser groups differed significantly from those of the CG. There was also a decrease in the OHIP-14 scores in the four groups. The IR3W laser group scores differed significantly from those of the CG. LLLT reduces the symptoms of BMS and may be an alternative therapeutic strategy for the relief of symptoms in patients with BMS.

Oral mucositis in pediatric patients undergoing hematopoietic stem cell transplantation: clinical outcomes in a context of specialized oral care using low-level laser therapy

OM is a painful inflammatory condition of the oral mucosa, derived from the toxic effects of chemotherapy and radiotherapy. High OM severity is frequently present in HSCT pediatric patients, who exhibit multiple painful ulcers that limit their mastication and swallowing, leading to poor nutritional status. Few studies have demonstrated OM clinical outcomes in young patients undergoing HSCT. Feasibility of oral care and LLLT on OM prophylaxis and treatment is also poorly discussed. The aim of this study was to describe a specialized oral care protocol that included LLLT for pediatric patients undergoing transplantation and to demonstrate the clinical outcomes after OM prevention and treatment. Data from OM-related morbidity were collected from 51 HSCT pediatric patients treated daily with LLLT, followed by standard oral care protocols. All the patients, even infants and young children, accepted the daily oral care and LLLT well. The majority (80.0%) only exhibited erythema in the oral mucosa, and the maximum OM degree was WHO II. Patients who had undergone autologous and HLA-haploidentical transplants showed OM with the lowest severity. The frequency of total body irradiation and methotrexate prescriptions was higher in adolescents when compared with infants (p = 0.044), and adolescents also exhibited OM more severely than infants and young children. We found that good clinical outcomes were obtained using this therapy, mainly in regard to the control of OM severity and pain reduction in the oral cavity. Specialized oral care, including LLLT, is feasible and affordable for HSCT pediatric patients, although some adaptation in the patient's oral hygiene routine must be adopted with help from parents/companions and clinical staff.

Class IV laser therapy as treatment for chemotherapy-induced oral mucositis in onco-haematological paediatric patients: a prospective study

BACKGROUND

Oral mucositis is a debilitating side effect of chemotherapy. Laser therapy has recently demonstrated efficacy in the management of oral mucositis (OM).

AIM

This prospective study was conducted to evaluate the efficacy of class IV laser therapy in patients affected by OM.

DESIGN

Eighteen onco-haematological paediatric patients receiving chemotherapy and/or haematopoietic stem cell transplantation, prior to total body irradiation, affected by OM, were enrolled in this study. Patients were treated with class IV laser therapy for four consecutive days; the assessment of OM was performed through WHO Oral Mucositis Grading Objective Scale, and pain was evaluated through visual analogue scale. Patients completed a validated questionnaire, and photographs of lesions were taken during each session. Patients were re-evaluated 11 days after the first day of laser therapy.

RESULTS

All patients demonstrated improvement in pain sensation, and all mucositis was fully resolved at the 11-day follow-up visit, with no apparent side effects. Laser therapy was well tolerated with remarkable reduction in pain associated with oral mucositis after 1-2 days of laser therapy.

CONCLUSIONS

Given class IV laser therapy appears to be safe, non-invasive, and potentially effective, prospective, randomized, controlled trials are necessary to further assess efficacy and to determine optimal treatment parameters.

Alternative approach to the management of postoperative pain after pediatric surgical procedures

Aim: This paper reports two clinical cases in which the application of low-level laser therapy (LLLT) enhanced the postoperative symptoms after pediatric surgical procedures.

Background: The uses of novel technologies allow more comfort to the patients and ensure a rapid procedure, and LLLT application has shown a positive effect in the prevention of discomfort after invasive procedures.

Case description: Low-level laser therapy protocol was applied after surgical removal of supernumerary tooth and frenectomy resulting in less swallow and pain with no need of medication intake.

Conclusion: The laser application was well accepted by both children and parents and showed a clinical efficiency in the follow-up examinations beyond the satisfactory quality of wound healing.

Clinical significance: The LLLT approach is an excellent adjuvant therapy resource for delivery an optimal postoperative after surgical procedures in children.

How to cite this article: Paschoal M, Souza J, Santos-Pinto L, Pansani C. Alternative Approach to the Management of Postoperative Pain after Pediatric Surgical Procedures. Int J Clin Pediatr Dent 2014;7(2):125-129.

[Use of laser for the prevention and treatment of oral mucositis induced by radiotherapy and chemotherapy for head and neck cancer]

One of the complications of radiotherapy and chemotherapy is oral mucositis. Since the low energy laser is one of the most frequently recommended interventions by authors and international societies, the aim of this study is to review the scientific evidence on the use of lasers as a preventive and therapeutic in oral mucositis associated with treatment of cancer. We performed a literature search in PubMed and The Cochrane Collaboration Library, limiting the search to the last 20 years. We finally included 29 articles that contained 30 studies. Low energy laser phototherapy seems a promising intervention in both the prevention and treatment of oral mucositis associated with cancer treatment. Virtually all studies reviewed showed good results with no adverse effects and reductions in both incidence and severity of mucositis in all types of cancer treatments.

Chemotherapy-induced oral mucositis: effect of LED and laser phototherapy treatment protocols

BACKGROUND AND OBJECTIVE

Over the last few decades, many studies have focused on the effect of lasers on the management of oral mucositis in oncologic patients treated with chemotherapy and/or radiotherapy. However, the effect of light-emitting diode (LED) has been poorly studied, and was not compared with that of laser phototherapy (LPT). For this reason, the aim of the present study was to clinically compare the effect of these two therapies on chemotherapy-induced oral mucositis (CIOM) and pain.

METHODS

Forty patients with CIOM were divided into two groups: G1, patients treated with LPT; G2, patients treated with LED. The treatment was administered during 10 consecutive days, with exception of weekends. LPT was applied using an InGaAlP laser (660 nm/40 mW/6.6 J cm-(2)/0.24 J per point/0.036 cm(2) of spot size). LED phototherapy was applied using 0.24 J per point/80 mW/630 nm/1 cm(2) of spot size. CIOM was assessed during each session in accordance to the World Health Organization (WHO) score. The patient self-assessed pain was scored on a visual analog scale (VAS).

RESULTS

The mean VAS and WHO scores were significantly smaller in the LED group (p<0.05). However, both groups required the same number of days to reach score zero for mucositis and pain (p>0.05). Moreover, in the group with severe mucositis (score III), there was a lower frequency of patients with complete healing and pain relief, with the exception of analgesia in G2, in which almost all patients were completely relieved from pain.

CONCLUSIONS

These findings suggest that LED therapy is more effective than LPT in the treatment of COIM, with the parameters used in the present study.

Effect of low-level laser therapy on oral keratinocytes exposed to bisphosphonate

Bisphosphonate-related osteonecrosis of the jaw (BRONJ) is a side effect of bisphosphonate therapy. However, its pathophysiology is not yet fully elucidated, and effective treatment of BRONJ remains unclear. The aim of this study is to investigate the effects of alendronate on oral keratinocytes and of low-level laser therapy (LLLT) on alendronate-treated keratinocytes, specifically by evaluating their viability, apoptosis, and wound healing function after irradiation. Oral keratinocyte cells (HaCaT) were exposed to 25 μM alendronate. Then, laser irradiation was performed with a low-level Ga-Al-As laser (λ = 808 ± 3 nm, 80 mW, and 80 mA; NDLux, Seoul, Korea) using 1.2 J/cm(2) energy dose. Viability was analyzed using MTT assay. Apoptosis was measured by Hoechst staining, caspase assay. Changes in secretion of IL-8, VEGF, and collagen type I were studied by ELISA and immunofluorescence microscopy. Scratch wound assays were also performed to measure cellular migration. Our results show that alendronate inhibits keratinocyte viability, expression of IL-8, VEGF, and collagen type I which are intimately related to healing events and cell migration while promoting apoptosis. Our results serve to demonstrate the utility of LLLT in partially overcoming the inhibitory effects of this bisphosphonate. From these results, the authors believe that the present study will provide an experimental basis for a fuller explanation of the clinical effects of LLLT as a BRONJ treatment modality.