A Novel Metabolic Neuroimaging Strategy For Etiological Diagnosis Of TMDs

To detect central metabolic differences in temporomandibular disorders (TMDs) induced by occlusal disorder and psychological stress, thereby clarifying relevant etiological diagnoses. This study was approved by the institutional ethics committee. Male Sprague-Dawley (SD) rats were used to establish models of TMDs induced by occlusal disorder and psychological stress. The success of modeling was evaluated through body weight measurement, behavioral experiments, micro-CT scanning of the condyle, and histological staining of condylar tissue. Micro-PET/CT scanning was employed to analyze metabolic differences in central nuclei between the two etiological types of TMDs, and immunofluorescence staining was used for pathological validation. A significant decrease in central glucose metabolism was observed in TMDs rats induced by occlusal disorder and psychological stress. Moreover, there was a substantial difference between the two groups in the right frontal association cortex and right cingulate cortex, with the psychological stress group exhibiting lower glucose metabolism. Additionally, immunofluorescence staining for the astrocyte-specific marker glial fibrillary acidic protein (GFAP) revealed a decrease in GFAP expression in the target brain regions of both groups, with a more pronounced reduction in the psychological stress group. Occlusal disorder and psychological stress lead to heterogeneity in brain nucleus activity in TMDs rats, indicating differences in cerebral glucose metabolism between the two etiological types of TMDs. This finding may provide new strategies for the etiological diagnosis of TMDs in the future.