Is hyaluronic acid injection effective for the treatment of temporomandibular joint disc displacement with reduction?

Abstract Purpose The use of HA injections and occlusal splints have been suggested in the treatment of temporomandibular joint (TMJ) derangements, but no sufficient data are available regarding the controlled clinical trials comparing HA injection with another treatment modality. The purpose of this study was to compare the effectiveness of single HA injection, double HA injection, and splint therapy for the treatment of TMJ disc displacement with reduction (DDR). Materials and Methods A prospective clinical trial was designed. The study sample included patients with DDR of the TMJ. The primary predictor variable was the treatment method. Patients were divided into four groups as follows: control, single hyaluronic acid (HA) injection, double HA injection, and stabilization splint therapy. Patients were randomly assigned to one of three treatment groups. The control group was self selected. The primary outcome variable was pain at rest and mastication. The secondary outcome variables were the TMJ noise, quality of life, and the level of jaw movements. Clinical symptoms and jaw movements were evaluated at baseline and at the 6-month follow-up. We performed descriptive, comparative, correlation, and multivariate analyses. Results The sample included 51 patients (with 66 TMJs) aged 18 to 48 years. All treatment groups showed significant improvement compared with the baseline values with regard to pain, TMJ noise, quality of life, and maximum mouth opening (MMO) at the 6-month follow-up (P < .05). However, both HA injection groups indicated superior improvement with regard to pain, MMO, and quality of life when compared with the stabilization splint group (P < .05). Conclusions The results of this study have shown that both HA injection and stabilization splint are acceptably successful treatment modalities to improve the clinical signs and symptoms of TMJ with DDR.