Novel hypotheses related to Temporomandibular joint derived from Ankylosing spondylitis

Temporomandibular joint disorders in seronegative spondyloarthritis: what a rheumatologist needs to know?

Temporomandibular joint (TMJ) can be affected in the context of spondyloarthritis (SpA) with detrimental impact on individuals' quality of life. Intra-articular inflammation, synovitis, enthesitis, disc displacement and cervical vertebrae malalignment are some of the pathophysiological phenomena involved. Temporomandibular joint disorders (TMD) incidence appears to be higher in patients with ankylosing spondylitis and psoriatic arthritis, especially when clinical evaluation includes not only imaging but relevant history, TMJ examination and diagnostic criteria for TMD. The Visual Analogue Scale (VAS) pain score and Health Assessment Questionnaire Disability Index (HAQ) quality of life score could be useful tools. Panoramic radiographs and ultrasound can be used for screening but in symptomatic patients magnetic resonance imaging (MRI) is preferable. Conservative management and early pharmacological treatment can prevent permanent joint impairment. For refractory cases, early referral to Legislation for Oral and Maxillofacial Surgery (OMFS) specialists is indicated. The aim of this narrative review is to address the involvement of TMJ in SpA and to encourage clinicians to incorporate TMJ assessment in their physical examination and basic screening.

Association between axial spondyloarthritis and temporomandibular disorders: A systematic review

This study aimed to assess the frequency of temporomandibular disorders (TMDs) in patients with axial spondyloarthritis (axSpA) compared with the healthy individuals. We systematically searched PubMed, Embase, Scopus, Web of Science, CINAHL, and Google Scholar databases from their inception until 2022, without language restriction. A standardized dataset was used to extract data from the observational studies. Patients were required to have axial spondyloarthritis and clinical and/or radiographic evidence of temporomandibular joint dysfunction. Meta-analysis was performed with a random effects model. A systematic review was registered under number CRD42020206283. We identified seven relevant studies, which provided data for 745 patients and 216 temporomandibular disorders events. The combined odds ratio (OR) showed that the risk of temporomandibular disorders in individuals with axial spondyloarthritis was higher than the control group (pooled OR = 5.26, 95% CI 2.50-11, 06; p < 0.02; I2  = 58%). Also, these individuals do not appear to refer possible temporomandibular joint symptoms to the rheumatologist or dentist. The results of this systematic review and meta-analysis suggest that patients with axial spondyloarthritis have an increased frequency of temporomandibular disorders. TMDs seem to be secondary to postural alterations rather than direct involvement of the temporomandibular joints (TMJs).

Suprafoveal condylar arthroplasty in unilateral disc displacement without reduction - A retrospective study

The aim of this study was to evaluate the efficacy of suprafoveal condylar arthroplasty (SFCA) in the management of patients with unilateral temporomandibular joint (TMJ) disc displacement without reduction (DDWoR). A retrospective study comprising patients who underwent unilateral SFCA for clinically and radiologically confirmed unilateral DDWoR from 2008 to 2020 was conducted. Patients older than 18 years at the time of diagnosis with a minimum of 6 months of unsuccessful non-surgical and minimally invasive management (including diet and life style modification, physiotherapy, appliance therapy, pharmacotherapy, arthrocentesis and arthroscopic lysis and lavage) before undergoing surgery with a minimum of 1 year follow-up post-surgery were included in the study. Patients with other articular and extra-articular causes of restricted mouth opening, prior history of mandibular surgery and/or trauma, growth abnormalities, systemic, metabolic, infective, neoplastic conditions affecting TMJ, including gross occlusal disharmony, untreated existing para-functional habits and bilateral DDWoR, were excluded from the study. Patients were assessed in terms pain on a visual analog scale (VAS), interincisal mouth opening (MO) and subjective assessment of mandibular range of movements including deviation of mouth opening, protrusion and ability for contralateral laterotrusion. 23 patients (10 males and 13 female) were included in the study, with a mean age of 35.09 years and mean follow up period of 37.7 months (range = 12-58; SD = 15.3). The mean pain scores on the VAS reduced from 6.35 preoperatively to 1.13 postoperatively and were found to be statistically significant (p < 0.0001). The improvement of the mean pre-operative mouth opening of 21.83 mm to a mean post-operative mouth opening of 42.09 mm was also found to be statistically significant (p < 0.0001). The subjective improvement in protrusive (p = 0.0003), laterotrusive (p = 0.0005) and opening movements (p = 0.0001) after 1 year were also found to be statistically significant. No patient developed any significant changes in occlusion post-operatively. Four of 23 (17.3%) patients developed transient neuromotor deficit of the temporal branch of the facial nerve. Within the limitations of the study, it seems that SFCA (without addressing the disc) might be an alternative to less invasive treatment approaches, if the latter turned out not to be successful.

Prevalence of Temporomandibular Joint Disorders in Patients with Ankylosing Spondylitis: A Cross-Sectional Study

Background

This study sought to investigate which temporomandibular disorders (TMD) can be expected in patients with ankylosing spondylitis (AS) and to determine the combined impact of these conditions on the psychological status, chronic pain, and functional disability.

Material and Methods

A cross-sectional study composed of 30 patients between 18 and 65 years with ankylosing spondylitis was performed. The research protocol considered the evaluation of outcomes related to the ankylosing spondylitis (HLA-B27 antigen, Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Bath Ankylosing Spondylitis Functional Index (BASFI) and Health Assessment Questionnaire – Spondylitis (HAQ-S)) and temporomandibular disorders (axis I and II of the Research Diagnostic Criteria for Temporomandibular Disorders – RDC/TMD). Descriptive analyses were applied to express the results.

Results

The sample presented both AS and TMD, most of them (24) were diagnosed with conventional AS (HLA-B27 positive). The BASDAI was scored as 7.70 (2.30) (high activity of AS disease). Functional disability represented by high scores of BASFI [7.00 (2.63)] and HAQ-S [1.79 (0.62)] demonstrates the severe impact of the disease on the daily routine and quality of life. According to RDC/TMD diagnostic criteria, 17 (57%) share the three groups of TMD, and 9 (30%) share two groups of TMD (Group I and III). Over 73% of the volunteers scored high levels of chronic pain (Grade III and IV) associated with a high depression scale score. The sample scored the somatization scale (with and without pain) as severe.

Conclusion

Patients with ankylosing spondylitis presented a high prevalence of temporomandibular disorder, most of them having the degenerative forms of TMJ disease. AS and TMD cause moderate to severe chronic pain and a negative impact on psychological status and functional capacities.