Background and objectives: Temporomandibular joint disorders (TMJDs) are associated with pain and reduced jaw mobility. The aim of this study was to compare the outcome of patients with TMJ arthralgia when submitted to four different treatment modalities, in some cases using intra-articular injections of substances with anti-inflammatory properties and in others, a more conservative approach consisting only of a bite splint. Materials and Methods: The sample was made up of 80 patients, randomly distributed into 4 groups of 20 patients each. Each patient was given a nocturnal bite splint. One of the groups was treated with the bite splint only, while each patient in the other 3 was injected with betamethasone, sodium hyaluronate, or platelet-rich plasma in addition to using the bite splint. Two variables were assessed, namely pain intensity between 0 to 10 according to the visual analogue scale and maximum pain-free mouth opening in mm. The patients were evaluated at four different points: at the beginning of the treatment, as well as one week, one month and six months after initiation.
Results: The results showed that maximum pain-free mouth opening improved in all the groups that made up the sample, with either a reduction in pain severity or with no pain. However, the group injected with platelet-rich plasma yielded the best results after six months, while patients treated with sodium hyaluronate or betamethasone obtained the best results at the end of the first week.
Conclusions: We concluded that all the treatments used caused a reduction in pain and increased pain-free mouth opening. The splint combined with the platelet-rich plasma injection achieved long-term success.
Keywords: arthralgia; betamethasone; bite splint; platelet-rich plasma; sodium hyaluronate; temporomandibular disorders.