Aggrecanase analysis of synovial fluid of temporomandibular joint disorders

Immunohistochemical Markers of Temporomandibular Disorders: A Review of the Literature

Temporomandibular disorders (TMD) are a group of internal derangements encompassing dysfunction, displacement, degeneration of the temporomandibular joints and surroundings muscles of mastication, often accompanied by pain. Relationships between TMD and various chemical biomarkers have been examined throughout the years. This paper aims to gather evidence from the literature regarding other biomarkers and presenting them as one systematic review to investigate the potential links between TMD and different biochemical activity. To identify relevant papers, a comprehensive literature search was carried out in MEDLINE/PubMED, EMBASE, Web of Science and a manual search was performed in the International Journal of Oral and Maxillofacial Surgery, Journal of Oral and Maxillofacial surgery, and Journal of Cranio-Maxillo-Facial Surgery. The literature review produced extensive results relating to the biochemical and immunohistochemical markers of TMD. Many enzymes, inflammatory markers, proteoglycans, and hormones were identified and organized in tables, along with a brief description, study design, and conclusion of each study. Through this review, recurring evidence provides confidence in suggesting involvement of certain biomarkers that may be involved in this complex pathogenesis, in addition to pointing to differences in gender prevalence of TMD. However, more organized research on large human samples needs to be conducted to delve deeper into the understanding of how this disease develops and progresses.

Oxygen-Ozone Therapy for Reducing Pro-Inflammatory Cytokines Serum Levels in Musculoskeletal and Temporomandibular Disorders: A Comprehensive Review

To date, the application of oxygen-ozone (O₂O₃) therapy has significantly increased in the common clinical practice in several pathological conditions. However, beyond the favorable clinical effects, the biochemical effects of O₂O₃ are still far from being understood. This comprehensive review aimed at investigating the state of the art about the effects of O₂O₃ therapy on pro-inflammatory cytokines serum levels as a modulator of oxidative stress in patients with musculoskeletal and temporomandibular disorders (TMD). The efficacy of O₂O₃ therapy could be related to the moderate oxidative stress modulation produced by the interaction of ozone with biological components. More in detail, O₂O₃ therapy is widely used as an adjuvant therapeutic option in several pathological conditions characterized by chronic inflammatory processes and immune overactivation. In this context, most musculoskeletal and temporomandibular disorders (TMD) share these two pathophysiological processes. Despite the paucity of in vivo studies, this comprehensive review suggests that O₂O₃ therapy might reduce serum levels of interleukin 6 in patients with TMD, low back pain, knee osteoarthritis and rheumatic diseases with a concrete and measurable interaction with the inflammatory pathway. However, to date, further studies are needed to clarify the effects of this promising therapy on inflammatory mediators and their clinical implications.

Th1/Th17/Th22 immune response and their association with joint pain, imagenological bone loss, RANKL expression and osteoclast activity in temporomandibular joint osteoarthritis: A preliminary report

It is well accepted that the presence of cytokines belonging to the Th1/Th17/Th22 axis of immuno-inflammatory response in the joint environment, such as IL-1β, IL-17 and IL-22, respectively, are associated with pathogenesis of several synovial joint degenerative disorders. During temporomandibular joint osteoarthritis (TMJ-OA), IL-1β and IL-17 have been implicated in the inflammation and resorption of sub-chondral bone; however, the role of Th22 response in the TMJ-OA pathophysiology has not been established. This study aimed to compare the expression of Th1/Th17/Th22-type cytokines, chemokines and chemokine receptors in synovial fluid samples obtained from TMJ-OA or disk displacement with reduction (DDWR) patients. In addition, it aimed to associate these levels with joint pain, imagenological signs of bone degeneration, RANKL production, osteoclastogenesis and osteoclast-induced bone resorption. Higher levels of IL-1β, IL-17 and IL-22 were expressed in TMJ-OA compared with DDWR subjects, and these increased levels significantly correlated with RANKL expression, joint pain and articular bone degeneration. Higher levels of CCR5, CCR6 and CCR7, as well as their respective ligands CCL5 and CCL20, responsible for recruitment of IL-1β, IL-17 and IL-22-producing cells, were over-expressed in TMJ-OA compared with DDWR subjects. Osteoclastogenesis and osteoclast-induced bone resorption were significantly greater in presence of synovial fluid from TMJ-OA compared with DDWR subjects. These data demonstrate that cytokines, CCLs and CCRs associated with the Th1/Th17/Th22 axis of immuno-inflammatory response are involved in TMJ-OA pathogenesis. These findings suggest that IL-22 is involved in the RANKL expression in TMJ-OA, which in turn induces differentiation of osteoclasts and subsequent resorption of sub-chondral bone.

The many faces of the genetics contribution to temporomandibular joint disorder

OBJECTIVES

Review the literature on candidate genes for temporomandibular joint disorder (TMD). Setting and Sample Population - Literature review.

MATERIALS AND METHODS

Two basic approaches were used to obtain literature in any language regarding genes and TMD. First, Medline, Embase, and Science Citation Index databases were searched using the keywords 'temporomandibular joint disorder' and 'temporomandibular joint dysfunction' for studies published from 1966 to 2007. Then, the references list of the studies obtained in the database was also considered.

RESULTS

Candidate genes for TMD include genes for individual variations in pain perception, gender and ethnicity, proinflammatory cytokines, female hormones, breakdown of extracellular matrix, and syndromic forms of TMD.

CONCLUSION

Most of the studies on genetic variation contributing to TMD are approaching the disease mainly from an immune-inflammatory perspective. Recent investigations of the genetic variables which may predict identifiable levels of pain perception may uncover new approaches to our traditional treatment modalities for the chronic pain patient.