Low-level laser therapy stimulates tissue repair and reduces the extracellular matrix degradation in rats with induced arthritis in the temporomandibular joint. Issue 6 (August 2016)

• Record Type: Journal Article
• Authors: Lemos, George; Rissi, Renato; Souza Pires, Ivan; Oliveira, Letícia; Aro, Andrea; Pimentel, Edson; Palomari, Evanisi
• Is Part Of: Lasers in medical science. Volume 31:Issue 6(2016)
• Page Start: 1051
• Page End: 1059
• Publication Date: 2016-08
• Subjects: Temporomandibular joint disorders -- Arthritis -- Inflammation -- Low-level laser therapy; Lasers in medicine -- Periodicals; 610.28
• DOI: 10.1007/s10103-016-1946-3
• Languages: English
• ISSNs: 0268-8921

Abstract

Abstract The objective of this study was to characterize morphological and biochemistry action of low-level laser therapy (LLLT) on induced arthritis in the temporomandibular joint (TMJ) of rats. Twenty-four male Wistar rats were randomly divided into groups with 12 animals each: (AG) group with arthritis induced in the left TMJ and (LG) group with arthritis induced in the left TMJ and treated with LLLT (830 nm, 30 mW, 3 J/cm2 ). Right TMJs in the AG group were used as noninjected control group (CG). Arthritis was induced by intra-articular injection of 50 μl Complete Freund's Adjuvant (CFA) and LLLT began 1 week after arthritis induction. Histopathological analysis was performed using sections stained with hematoxylin-eosin, Toluidine Blue, and picrosirius. Biochemical analysis was determined by the total concentration of sulfated glycosaminoglycans (GAGs) and evaluation of matrix metalloproteinases (MMP-2 and MMP-9). Statistical analysis was performed using paired and unpairedt tests, withp < 0.05. Compared to AG, LG had minor histopathological changes in the TMJ, smaller thickness of the articular disc in the anterior (p < 0.0001), middle (p < 0.0001) and posterior regions (p < 0.0001), high birefringence of collagen fibers in the anterior (p < 0.0001), middle (p < 0.0001) and posterior regions (p < 0.0001) on the articular disc, and statistically lower activity of MMP-2 latent (p < 0.0001), MMP-2 active (P = 0.02), MMP-9 latent (p < 0.0001), and MMP-9 active (p < 0.0001). These results suggest that LLLT can increase the remodeling and enhancing tissue repair in TMJ with induced arthritis.