Mucositis

J Clin Periodontol. 2003 Apr;30(4):353-8.

AIM: The aim of this in vitro study was to evaluate a potential stimulatory effect of low-level laser
irradiation on the proliferation of human periodontal ligament fibroblasts (PDLF).
MATERIALS AND METHODS: PDLF obtained from third molar periodontal ligaments were
cultured under standard conditions and spread on 96-well tissue culture plates. Subconfluent
monolayers were irradiated with an 809-nm diode laser operated at a power output of 10 mW in
the continuous wave (cw) mode at energy fluences of 1.96- 7.84 Jcm-2. The variable irradiation
parameters were the time of exposure (75-300 s per well) and the number of irradiations (1-3).
After laser treatment, the cultures were incubated for 24 h. The proliferation rate of the lased and
control cultures was determined by means of fluorescence activity of a reduction-oxidation
(REDOX) indicator (Alamar Blue Assay) added to the cell culture. Proliferation, expressed in
relative fluorescence units (RFU), was determined 24, 48 and 72 h after irradiation.
RESULTS: The irradiated cells revealed a considerably higher proliferation activity than the
controls. The differences were significant up to 72 h after irradiation (Mann-Whitney U-test,
p<0.05).
CONCLUSION: A cellular effect of the soft laser application is clearly discernible. Clinical studies are needed to evaluate whether the application of low-level laser therapy might be beneficial in regenerative periodontal therapy.

The Effects Of Low Level Laser Irradiation On Osteoblastic Cells
Coombe AR, Ho CT, Darendeliler MA, Hunter N, Philips JR, Chapple CC, Yum LW.
Discipline of Orthodontics, Faculty of Dentistry, University of Sydney, New South Wales,
Australia; Institute of Dental Research, United Dental Hospital, New South Wales, Australia.

Clin Orthod Res. 2001 Feb;4(1):3-14.

Low level laser therapy has been used in treating many conditions with reports of multiple clinical effects including promotion of healing of both hard and soft tissue lesions. Low level laser therapy as a treatment modality remains controversial, however. The effects of wavelength, beam type, energy output, energy level, energy intensity, and exposure regime of low level laser therapy remain unexplained. Moreover, no specific therapeutic window for dosimetry and mechanism of action has been determined at the level of individual cell types. The aim of this study was to investigate the effects of low level laser irradiation on the human osteosarcoma cell line, SAOS-2.
The cells were irradiated as a single or daily dose for up to 10 days with a GaAlAs continuous
wave diode laser (830 nm, net output of 90 mW, energy levels of 0.3, 0.5, 1, 2, and 4 Joules).
Cell viability was not affected by laser irradiation, with the viability being greater than 90% for all
experimental groups. Cellular proliferation or activation was not found to be significantly affected
by any of the energy levels and varying exposure regimes investigated. Low level laser irradiation
did result in a heat shock response at an energy level of 2 J. No significant early or late effects of laser irradiation on protein expression and alkaline phosphatase activity were found. Investigation of intracellular calcium concentration revealed a tendency of a transient positive change after irradiation. Low level laser irradiation was unable to stimulate the osteosarcoma cells utilised for this research at a gross cell population level. The heat shock response and increased intracellular calcium indicate that the cells do respond to low level laser irradiation. Further research is required, utilising different cell and animal models, to more specifically determine the effects of low level laser irradiation at a cellular level. These effects should be more thoroughly investigated before low level laser therapy can be considered as a potential accelerator stimulus for orthodontic tooth movement.

Patients with moderate chemotherapy-induced mucositis: pain therapy using low intensity lasers.

Nes AG; Posso MB

International nursing review; VOL: 52 (1); p. 68-72 /200503/

Buskerud University, Drammen, Norway. s-oddmun@online.no

BACKGROUND: Intensive cancer therapy normally affects malignant and normal cells with high replication rates. Cells in the gastrointestinal tract are therefore commonly affected by cytotoxins. This often results in the development of chemotherapy-induced oral mucositis (COM). COM is the inflammatory response of the oral mucous membrane to the chemotherapy drugs. Low level laser therapy (LLLT) has proved to be effective in treating and repairing biologically damaged tissue and to reduce pain. LLLT has also proven to be an efficient method for the prevention of oral mucositis. OBJECTIVE: To investigate the effect of LLLT on pain relief among patients who have developed COM. METHOD: The study was performed as a clinical test with a sample consisting of 13 adult patients receiving oncology treatment. The patients were treated during a 5-day period, and the pain was measured before and after each laser application. The laser used was an AsGaAl, with a wavelength of 830 nm and a potency of 250 mW. The energy given was 35 J cm(-2). ANALYSIS: The results were analysed using the Wilcoxon test. RESULTS: There was a significant (P = 0.007) 67% decrease in the daily average experience of pain felt before and after each treatment, confirming that LLLT can relieve pain among patients who have developed COM. STUDY LIMITATIONS: The low number of COM patients at the hospital did not allow a control group to be included in the study, and therefore the results contain a potential placebo effect.

IMPLICATIONS FOR NURSING CARE: The most important benefit the authors consider to be the value for the patients of better and quicker treatment with a drastic reduction in painful mucositis.

Low-level laser for prevention and therapy of oral mucositis induced by chemotherapy or radiotherapy.

Genot MT; Klastersky J

Current opinion in oncology; VOL: 17 (3); p. 236-40 /200505/

Laboratoire d'Investigation Clinique H.J. Tagnon, Institut Jules Bordet, Centre des Tumeurs, Université Libre de Bruxelles, Bruxelles, Belgium.

PURPOSE OF REVIEW: Oral mucositis is a common morbid condition associated with chemotherapy or radiotherapy for which there is no standard prophylaxis or treatment. There is increasing evidence that the use of low-level laser can reduced the severity of mucositis associated with chemotherapy or radiation therapy. The purpose of this review is to examine the available evidence for it. RECENT FINDINGS: For most approaches commonly used to prevent or treat chemotherapy-associated or radiotherapy-associated oral mucositis, a recent panel of experts could not find sufficient levels of evidence to recommend or suggest their use. As for low-level laser therapy, the results are difficult to assess and compare because of interoperator variability and because clinical trials are difficult to conduct in that field. Nevertheless, there is accumulating evidence in support of low-level laser therapy.