RESUMEN
Objective The purpose of this study was to explore the efficacy of low level laser treatment (LLLT) combined with initial periodontal therapy in treating chronic periodontits.Methods Eighteen patients with chronic periodontitis were randomly treated in a spit-mouth design with combination of laser (808 nm,80 mW) treatment with scaling and root planing (experimental) or with scaling and root planing alone (contol) after OHI and supragingival cleaning.Clinical parameters of sulcus bleeding index (SBI),periodontal probing depth (PD) and clinical attachment loss (CAL) of both sides were recorded and gingival crevicular fluid samples were collected at baseline and 1,4,12 weeks after the treatment.GCF samples were analyzed for b-FGF,IL-1β,IL-8 level using ELISA assay.Results For the change of SBI and PD,only SBI in the experimental group experienced significant reduction (P＜0.05) at 1 week compared with baseline (P＜0.05),and the reduction in both groups were statistically significant (P＜0.05) at 4 weeks.The same situation occurred while both experimental groups made more significant difference (P＜0.01) at 12 weeks.The reduction of SBI was obvious in both groups when the PD was more than 6 mm.For CAL,the experimental group showed signs of improvement (P＜0.05) at 4 weeks; both groups indicated improvement (P＜0.05),while the experimental was more significant (P＜0.01) at 12 weeks.For the levels of b-FGF,it showed steady rise after treatment in experimental group,while it went up to the baseline after falling in control group.At 12 weeks,there were statistical significance of differences between two groups (P＜0.05).The changes of IL-1β and IL-8,in the experimental group showed better results than that in control group,while the difference between two groups was not significant (P＞0.05).Conclusion LLLI can accelerate the healing of periodontal tissue by reducing the SBI,decreasing the PD,improving the CAL and increasing levels of b-FGF in the GCF of the patients.
RESUMEN
Effects of phototherapy using low-level lasers depend on irradiation parameters and the type of laser used. The aim of the present study was to evaluate the effect of phototherapy on the proliferation of cultured C2C12 myoblasts under different nutritional conditions using low-level GaAlAs and InGaAlP lasers with different parameters and incubation periods. C2C12 cells cultured in regular and nutrient-deficient medium were irradiated with low-level GaAlAs (780 nm) and InGaAlP (660 nm) lasers with energy densities of 3.8, 6.3 and 10 J/cm2, and 3.8, 10 and 17.5 J/cm2, respectively. Cell proliferation was assessed 48 and 72 h after irradiation by MTT assay. There were no significant differences in cell proliferation between laser-treated myoblasts and control cultures for any of the parameters and incubation periods. Further studies are necessary to determine the correct laser parameters for optimizing the biostimulation of myoblasts.