Interleukin-6 expression in disc derangement of human temporomandibular joint and association with osteoarthrosis

Abstract

The inflammatory process is a coordinated response that protects host after infection or trauma, involving several molecular reactions. Once the inflammation is closely linked to the process of destruction of the temporomandibular joint, this study aims to examine, by immunohistochemistry, the expression of interleukin-6 (IL-6), an important inflammatory marker, in temporomandibular articular discs of patients with anterior disc displacement with (ADDwR) and without reduction (ADDwoR) and its association with osteoarthrosis (OA). Thirty-eight (n = 38) articular discs were divided into two cutoffs: 1) analysis 1: 4 control (acute pathology), 17 ADDwR, 17 ADDwoR; and 2) analysis 2: without OA (n = 21) and with OA (n = 17). The area of immunostaining was compared statistically between groups (p < 0.05). In the disc samples, no significant differences were observed between the groups ADDwR and ADDwoR, and with and without OA, in respect to the expression of IL-6 by immunohistochemical examination. Future studies should be conducted with a larger sample size, which could clarify the association of the inflammatory mediator IL-6 with temporomandibular joint dysfunction.

The Temporomandibular Joint: A Critical Review of Life‐Support Functions, Development, Articular Surfaces, Biomechanics and Degeneration

“…4 Compared to the severe pain associated with osteoarthritis in other joints, DJD of the TMJ is usually painless, so it is best deemed an osteoarthrosis. 60 The relative lack of pain with DJD is another highly conserved characteristic of the jaws to provide life support functions under adverse conditions. 4,61,62 The degeneration has been associated with elevated anxiety and stress associated with chronic parafunction, typically nocturnal clenching.…”

Biomarkers for Temporomandibular Disorders: Current Status and Future Directions

“…The association between inflammatory processes and destruction of TMJ elements were illustrated in previous research. As a result, IL-6 was regarded as among the crucial proinflammatory cytokines, which lead to the pathogenesis of TMJ with ID [80,81].…”

“…Notably, IL-6 is an essential element in the transformation of acute inflammation to chronic, which exhibits a double impact [82]. In this case, this impact may be pro-inflammatory at several degrees and it may also display an anti-inflammatory profile at other degrees [80]. The IL-6 plasma concentrations could be identified within 60 min after the occurrence of tissue injury, with a peak ranging from four to six hours to 10 days [80].…”

“…In this case, this impact may be pro-inflammatory at several degrees and it may also display an anti-inflammatory profile at other degrees [80]. The IL-6 plasma concentrations could be identified within 60 min after the occurrence of tissue injury, with a peak ranging from four to six hours to 10 days [80]. Moreover, IL-6 contributes to the maturation of macrophages, activation, and maturation of neutrophils, and the differentiation/maintenance of cytotoxic T-lymphocytes and natural killer cells [83].…”

Inflammatory mediators related to arthrogenic temporomandibular dysfunctions

“…Moreover, IL-6 is important for the transition of acute inflammation to chronic 52 . The literature points IL-6 as one of the major pro-inflammatory cytokines that contribute to the pathogenesis of the TMJ inflammation and disorders 48,[53][54][55][56] .…”