Texture analyses of the lateral pterygoid muscle in young patients with temporomandibular disorder based on magnetic resonance imaging: a clinical study

Abstract Objectives The aim of this study was to investigate the etiology of temporomandibular disorder (TMD) in young patients using clinical and magnetic resonance imaging (MRI) features of the lateral pterygoid muscle (LPM). Materials and methods The patients were divided into four groups: healthy control, disc without displacement (DWoD), disc displacement with reduction (DDWR), and disc displacement without reduction (DDWoR) groups. Demographic information and clinical symptoms of patients in each group were recorded. LPM textures on magnetic resonance imaging (MRI) were compared among all groups. LPM fasciculation was examined. Results Patient sex or age did not differ significantly among groups, while several clinical symptoms and signs and some LPM texture parameters did. The proportion of type B LPM fascicles was significantly higher in DDWR and DDWoR groups than in healthy control and DWoD groups. Conclusion In this study, patients in DDWR and DDWoR groups showed unclear texture, no obvious regularity, and relatively uniform gray distribution on MRI of LPM. Clinical relevance This study found that the texture of the LPM in young TMD patients was different from that in normal people, especially in TMD patients with anterior disc displacement. Changes of the LPM may affect the position of the articular disc, thus provides a direction for scholars to study the etiology of TMD.