[A case of the temporomandibular arthritis during the orthodontic treatment]

The patient was a girl, 10 years 10 months of age, who had received the orthodontic treatment of chin cap and quad helix appliance for anterior and posterior crossbite. An opening click with pain in the left temporomandibular joint (TMJ) and trismus occurred in the period of treatment. The pumping manipulation and an anterior repositioning splint therapy were performed for closed lock. After the 4 months of wearing, the clinical symptoms disappeared and the upper second and lower first premolars were extracted for fixed appliance therapy. This case was finished and debanded after 2 years 10 months of the initial examination. At the end of active treatment, a maxillary removable retainer and a mandibular fixed canine to canine retainer were placed. The patient's dentition has remained essentially stable with a normal function of TMJ.