Matrix Metalloproteinases and Temporomandibular Joint Disorder: A Review of the Literature

Abstract

Temporomandibular disorders (TMD) are progressive degenerative disorders that affect the components of the temporomandibular joint (TMJ), characterized by pain and limitations in function. Matrix metalloproteinases (MMP) are enzymes involved in physiological breakdown of tissue that can have a pathological effect from an increase in activity during inflammation. A PubMed search of the current literature (within the past 10 years) was conducted to identify human studies involving matrix metalloproteinases activity in TMJ components of patients with TMD. Two separate searches results in 34 studies, six of which met inclusion criteria. Immunohistochemistry and gene analysis were used to evaluate MMP expression in the study groups. This review showed the strongest evidence for involvement of MMP-1, MMP-2, and MMP-9 in TMD; however, limitations included low sample sizes and a lack of recent clinical studies. Future research with more definitive conclusions could allow for additional pharmaceutical targets in MMP when treating patients with temporomandibular disorders.

NFkB and MMP-13 expression in condylar cartilage of temporomandibular joint with occlusal disharmony in vivo

“…27 MMP13 is a major enzyme that degrades the extracellular matrix by breaking peptide bonds in target proteins, so it will break down collagen and proteoglycans. 13,32 However, the research conducted still has its limitations due to the lack of samples of TMJ disorders. Therefore, further research on the specific effects and role of MMP is needed.…”

Cartilage Repair and Regeneration: Focus on Multi-Disciplinary Strategies

“…However, there are other gradients that could be interesting to investigate or even to combine. For instance, AC has been shown to have a gradient in stiffness [50][51][52][53]. Previous research has aimed to combine a stiffness gradient achieved by photo-crosslinking with a growth factor gradient achieved by mixing both TGF-β1 and BMP-2 in the hydrogel (before crosslinking).…”

“…Many studies evaluated several factors that can influence the failure rate of both these techniques. Among them, age, sex, etiology and size of the defect seem to modify the failure rate, with female patients, older patients and those affected by degenerative or larger lesions, complex cases, and patients undergoing salvage treatment being more at risk of failures [13,24,25,49,50]. Such profiling of patient characteristics which may influence the outcome were not possible in this series due to the low number of patients, although interesting findings could be underlined for the most suitable treatment indication based on the lesion size.…”

“…The increased protein levels of MMP-13 in the PTFH group may likely depend on the up-regulated activity of chondrocytes in producing MMPs after stress forces. These findings open preliminary biological insights into considering MMPs and fibrotic markers as attractive therapeutic targets by exploiting future technological advances like CRISPR-Cas9 [50]. Combining current ON strategies with small molecule inhibitors to block collagen type I, MMP-13 and ATX could improve the success of PTFH treatment [47,51].…”