1H-NMR-BASED SALIVARY METABOLOMICS FROM FEMALES WITH TEMPOROMANDIBULAR DISORDERS - A PILOT STUDY

Although temporomandibular disorder (TMD) is the second most common musculoskeletal disorder in the general population, the disease is multifactorial and presents symptoms common to other conditions; misdiagnosis can lead to treatment failure. In this case-control study, we performed, for the first time, a high-resolution ¹H-nuclear magnetic resonance spectroscopy metabolomic analysis of the saliva of 26 women with TMD of muscular origin (experimental group [EG]) at the beginning (EG-pre) and end (EG-post) of conservative treatment, and of 27 normal women (control group, CG) to identify a metabolic signature for TMD. One-way analysis of variance showed changes in the concentration of phenylacetate, dimethylamine, maltose, acetoin, and isovalerate. Partial least-square discriminant analysis showed that metabolite signals did not overlap in CG X EG-pre and EG-pre X EG-post, but overlapped in CG X EG-post. The area under the receiver operating characteristic curve was 1 in CG X EG-pre (95% CI, 1.000-1.000; p <0.002), 0.993 in EG-pre X EG-post (95% CI, 0.963-1.000), and 0.832 in CG X EG-post (95% CI, 0.699-0.961). These results suggest that the metabolomic profiles of women with and without TMD differ, while after treatment there is a lower distinction and slight tendency towards overlapping between CG and EG-post compared to pre treatment. We also found that phenylacetate, dimethylamine, maltose, acetoin, and isovalerate are potential biomarkers for TMD of muscular origin.

Keywords: Facial pain; biomarkers; conservative treatment; counseling; metabolomics; proton magnetic resonance spectroscopy; saliva; self-management; temporomandibular joint dysfunction syndrome.