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. 2025 Apr;75(2):596-604.
doi: 10.1016/j.identj.2024.08.006. Epub 2024 Sep 3.

Causal Relationship Between Autoimmune Arthritis and Temporomandibular Disorders

Xue-Feng Li  1 , Jun-Wei Cai  1 , Yuan-Yuan Hu  2 , Yu-Ming Niu  3
Affiliations

Causal Relationship Between Autoimmune Arthritis and Temporomandibular Disorders

Xue-Feng Li et al. Int Dent J. 2025 Apr.

Abstract

Objective: Accumulating evidence has indicated a close interrelation between autoimmune arthritis (AA) and temporomandibular disorders (TMD), but the causality is still unclear. The study aimed to explore the causal inference between AA and TMD using a bidirectional Mendelian randomization analysis.

Methods: Online genome-wide association study data on rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis, and TMD were obtained from the FinnGen and IEU databases. Causality was using the inverse variance-weighted method as the primary analysis and supplemented by other methods. Sensitivity analyses, including heterogeneity tests, horizontal pleiotropy tests, and leave-one-out methods, were conducted to investigate the stability and reliability of the results.

Results: The inverse variance-weighted test indicated that several AA types could causally increase the TMD risk, including overall RA (odds ratio [OR] = 1.348, 95% confidence interval [CI] = 1.1232-1.618, P = .001), subtype nRA (OR = 1.118, 95% CI = 1.044-1.197, P = .001), and AS (OR = 1.060, 95% CI = 1.024-1.097, P = .001). Moreover, the causal association of the above combinations has been proven to be stable and reliable using sensitivity and other tests.

Conclusion: These findings suggest that RA and AS might be causally associated with an increased risk of TMD. However, more studies are needed to check the causal effects of AA on TMD and analyse the potential mechanisms further.

Keywords: Autoimmune arthritis; Mendelian randomization; Temporomandibular disorders.

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Conflict of interest statement

Conflict of interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this article.

Figures

Fig 1
Fig. 1
Flowchart of the study design. The red represented the forward MR analyses, with autoimmune arthritis as exposure and temporomandibular disorders as the outcome. The blue represented the reverse MR analyses, with temporomandibular disorders as exposure and autoimmune arthritis as the outcome. AA, autoimmune arthritis; TMD, temporomandibular disorders; MR, Mendelian randomization; SNPs, single-nucleotide polymorphisms.
Fig 2
Fig. 2
The forest plot of the causal effect of the autoimmune arthritis on temporomandibular disorders. RA, rheumatoid arthritis; pRA, seropositive rheumatoid arthritis; nRA, seronegative rheumatoid arthritis; AS, ankylosing spondylitis; TMD, temporomandibular disorders; PA, psoriatic arthritis; MR, Mendelian randomization analysis; OR, odds ratio; CI, confidence interval.
Fig 3
Fig. 3
The forest plot of the causal effect of the temporomandibular disorders on autoimmune arthritis. TMD, temporomandibular disorders; RA, rheumatoid arthritis; pRA, seropositive rheumatoid arthritis; nRA, seronegative rheumatoid arthritis; AS, ankylosing spondylitis; PA, psoriatic arthritis; MR, Mendelian randomization analysis; OR, odds ratio; CI, confidence interval.
See this image and copyright information in PMC

References

    1. Kapos FP, Exposto FG, Oyarzo JF, et al. Temporomandibular disorders: a review of current concepts in aetiology, diagnosis and management. Oral Surg. 2020;13:321–334. doi: 10.1111/ors.12473. - DOI - PMC - PubMed
    1. Schiffman E, Ohrbach R, Truelove E, et al. Diagnostic criteria for temporomandibular disorders (DC/TMD) for clinical and research applications: recommendations of the international RDC/TMD Consortium Network* and Orofacial Pain Special Interest Group†. J Oral Facial Pain Headache. 2014;28:6–27. doi: 10.11607/jop.1151. - DOI - PMC - PubMed
    1. Valesan LF, Da-Cas CD, Réus JC, et al. Prevalence of temporomandibular joint disorders: a systematic review and meta-analysis. Clin Oral Investig. 2021;25:441–453. doi: 10.1007/s00784-020-03710-w. - DOI - PubMed
    1. Chisnoiu AM, Picos AM, Popa S, et al. Factors involved in the etiology of temporomandibular disorders – a literature review. Clujul Med. 2015;88:473–478. doi: 10.15386/cjmed-485. - DOI - PMC - PubMed
    1. Su N, Liu Y, Yang X, et al. Association of malocclusion, self-reported bruxism and chewing-side preference with oral health-related quality of life in patients with temporomandibular joint osteoarthritis. Int Dent J. 2018;68:97–104. doi: 10.1111/idj.12344. - DOI - PMC - PubMed

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