ObjectiveThis study aimed to evaluate the effect of disc morphology and disc-condyle angle on the treatment of anterior repositioning splint (ARS) for anterior disc displacement with reduction (ADDwR).MethodsOn the basis of the inclusion and exclusion criteria, a total of 11 patients diagnosed with ADDwR were included. The effects of changes in disc length, thickness, and morphology classifications on the clinical symptoms, disc morphology parameters, and disc-condyle angles after ARS treatment were evaluated using magnetic resonance imaging and the Helkimo index.ResultsAfter ARS treatment, the Ai and Di of all patients with ADDwR decreased, the disc length increased, and the thickness decreased. The Ai of patients with slight ADDwR and those with type 1 joint discs was reduced to 0, with the most significant decrease observed in Di. The disc length of mild ADDwR (increased to 8.65 mm±1.79 mm) and type 5 disc (increased to 10.71 mm±2.62 mm) significantly increased the most. The disc thickness of slight ADDwR decreased to 3.08 mm±0.51 mm significantly.ConclusionThe therapeutic effect of ARS is correlated with the displacement degree and morphological features of the disc, providing evidence for clinical treatment decisions.