Irradiation by light-emitting diode light as an adjunct to facilitate healing of experimental periodontitis in vivo

Chang P-C, Chien L-Y, Ye Y, Kao M-J. Irradiation by light-emitting diode light as an adjunct to facilitate healing of experimental periodontitis in vivo. J Periodont Res 2013; 48: 135143. (c) 2012 John Wiley & Sons A/S Background and Objective: This study evaluated the biostimulatory effect of 660nm light-emitting diode (LED) as an adjunct in the treatment of experimental periodontitis. Material and Methods: Ninety-six Sprague-Dawley rats underwent experimental periodontitis by placement of a silk ligature followed with or without additive Porphyromonasgingivalis lipopolysaccharide (Pg-LPS) injection. Irradiation with LED light was performed at varying energy densities of 5, 10 and 15J/cm2, 1d after debridement and detoxification. Rats were killed at 3, 7 and 14d after irradiation with LED light, and the effect of irradiation was evaluated by descriptive histology and quantitative measurements of periodontal bone loss, inflammatory infiltration and cellular proliferation. Results: Reduction of inflammation, accelerated collagen deposition and realignment was noted following irradiation with LED light at densities of 10 and 15J/cm2, and temporary reduction of periodontal bone loss, as well as bundle bone apposition, was noted at day 3 in rats treated with 10J/cm2 light. The biomodulatory effect was stronger in sites treated with Pg-LPS injection. In sites without Pg-LPS injection, temporary reduction of inflammation was noted in all LED light-irradiated specimens at day 3. No significant change in cellular proliferation was noted in any LED light-treated group. Conclusions: LED light (660nm) with an energy density of 10J/cm2 appeared suitable as an adjunct modality for periodontitis by temporarily reducing inflammation, facilitating collagen realignment and bundle bone deposition. Future studies will aim to amplify the biostimulatory effect of LED light by adding a supplementary medium or repeated irradiation.