Background & Aims
Temporomandibular disorders (TMD) is a complex condition characterized by varying symptoms, notably pain of mild to moderate intensity and various durations [1]. While previous studies have investigated the association between pain disorders and the oral microbiome, the specific role of the microbiome in TMD pathophysiology remains inadequately explored [2,3]. This study aims to investigate the role of oral microbiome in TMD by specifically analyzing how microbial profiles correlate with clinical aspects such as pain characteristics or specific TMD sub-diagnosis. We hypothesize that distinct microbial patterns are associated with these clinical variables, potentially influencing the disorder’s progression and symptomatology.
Methods
This cross-sectional study included 130 TMD patients who visited the oral medicine department of Seoul National University Dental Hospital between April 2022 and December 2023. The patients were diagnosed as TMD according to the Diagnostic Criteria for TMD (DC/TMD) and the patients completed structured questionnaires examining psychological and general health aspects [4]. Whole saliva samples were collected on their first visit for microbial analysis [5]. 16S rRNA gene sequences were processed using QIIME 2 for microbial community analysis [6]. Operational Taxonomic Units were identified, and alpha and beta diversity metrics were calculated [7]. Comparative analysis involved correlating microbial diversity with clinical parameters including pain chronicity and specific diagnoses of TMD using PCoA, Krusal-Wallis H test and LEFSe analysis [8].
Results
The gender distribution was 105 females and 25 males. The average age was 37.63 ± 14.4 years. Based on the Graded Chronic Pain Scale, 36 participants were classified as high disability, while 94 were in the low disability group. Among the participants, 70 reported myalgia, 72 experienced arthralgia, 29 had TMD-associated headache (HA), 95 had disc displacement (DD), and 63 with osteoarthritis (OA). Microbiome analysis revealed significant differences in alpha diversity between the high disability group and low disability group. When grouping by disability grade, HA, DD, and OA, significant associations were observed in the microbiome profiles.
Conclusions
The findings of this study indicate a potential link between the oral microbiome composition and specific clinical manifestations of TMD.
Our findings suggest that specific microbial profiles might be intricately linked with the severity and subtypes of TMD symptoms, highlighting the potential of the oral microbiome as a diagnostic marker or therapeutic target. However, the cross-sectional nature of this study limits our ability to infer causal relationships. Future longitudinal studies are essential to establish temporal associations and understand the dynamic interplay between the microbiome and TMJD progression.
References
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[3] O? Mahony SM, Dinan TG, Cryan JF. The gut microbiota as a key regulator of visceral pain. PAIN. 2017;158:S19-S28. doi:https://doi.org/10.1097/j.pain.0000000000000779
[4] 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. Journal of oral & facial pain and headache. 2014;28(1):6-27. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4478082/
[5] Lee BM, Ji Woon Park, Jo J, Byung Hwan Oh, Chung GH. Comparative analysis of the oral microbiome of burning mouth syndrome patients. Journal of Oral Microbiology. 2022;14(1). doi:https://doi.org/10.1080/20002297.2022.2052632
[6] Bolyen E, Rideout JR, Dillon MR, et al. Reproducible, interactive, scalable and extensible microbiome data science using QIIME 2. Nature Biotechnology. 2019;37(8):852-857. doi:https://doi.org/10.1038/s41587-019-0209-9
[7] Sh Y, Sm H, S K, et al. Introducing EzBioCloud: A Taxonomically United Database of 16S rRNA Gene Sequences and Whole-Genome Assemblies. International journal of systematic and evolutionary microbiology. Published May 1, 2017. https://pubmed.ncbi.nlm.nih.gov/28005526/
[8] Segata N, Izard J, Waldron L, et al. Metagenomic biomarker discovery and explanation. Genome biology. 2011;12(6):R60. doi:https://doi.org/10.1186/gb-2011-12-6-r60
Presenting Author
Ji Woon Park
Poster Authors
Topics
- Specific Pain Conditions/Pain in Specific Populations: Orofacial Pain