Objectives: The purpose of this study was to investigate possible correlations between the type/quantity of inflammatory cells and pain severity symptoms and jaw disability in humans with TMJ disorders (TMJD). Methods: A tissue specimen retrieval analysis was performed in two subgroups of subjects: Group A (n=7) has TMJD, Group B (n=10) has TMJD and TMJ implant (Proplast/Teflon" or Silastic"). A cadaver/control group (n=10) was used in the analysis for TMJ tissue inflammation. Patients' pre-surgical clinical data (pain severity/mandibular function) was collected. Inflammatory cells were counted on 10 randomly selected grid squares by using light microscopy with appropriate specimen staining. Clinical outcomes were obtained relative to symptom severity (Symptom Severity Index [SSI]) and to jaw function (Jaw Function Questionnaire [JFQ] from RDC/TMD Axis II). Results: We have found that the number of T-lymphocytes and mast cells were correlated with the SSI (p=0.02 and p=0.05, respectively); the duration component of the SSI was significantly related with the presence of mast cells (p=0.03), and the pain tolerability component with the quantity of T-lymphocytes. B-lymphocytes were rarely found and a significant quantity of T-lymphocytes was present in Group B. The presence of mast cells was predominant in Group B. The degree of mandibular function impairment was significantly increased in group A (p=0.03), but it was not shown to be associated with the type or quantity of inflammatory cells present in the TMJ tissues. Conclusions: This study suggests that the severity of TMD pain symptoms might be correlated the presence of T-lymphocytes and mast cells in TMJ tissues; pain chronicity might be related with the presence of mast cells and the ability to tolerate pain with the number of T-lymphocytes. Further investigation with a larger sample size is ongoing and will be presented later.
Project supported by NIH/NIDCR TIRR N01-DE-22635.