RESUMO
Objective:To provide imaging evidence for the treatment of anterior disc displacement without reduction by the injection of sodium hyaluronate into temporomandibular joint (TMJ).Methods:40 patients with anterior disc displacement without reduction were injected 3 times with sodium hyaluronate into the TMJ.Patient's TMJ and clinical symptoms were examined 3,9 and 12 months after treatment.The clinical parameters of Fricton's Craniomandibular Index(Fricton index),maximal mouth opening(MMO),pain intensity of a visual analog scale(VAS) and CBCT radiographic data of 48 TMJs from 40 patients were analysed.Results:The CBCT images showed that at 9 and 12 months follow-up the surface of the condylus became smooth,the density of the cortical bone and the adjacent subcortical bone increased and osteophyte in condylar head decreased(P =0.026,P =0.001).As for disc displacement without osteoarthritts,9 months after treatment condylus were moved forward(P =0.038).VAS and Fricton index were reduced(P ＜0.05),MMO was increased (P ＜ 0.05).3-12 months after treatment,there was no statistical difference of Fricton index (P ＞ 0.05).Conclusion:Injection of sodium hyaluronate into TMJ can remodel the condylar bone surface but cant make condyle back to the middle of acetabulum.