We performed total TMJ replacement to improve respiratory status and correct occlusion in six patients with destruction of the temporomandibular joint (TMJ) caused by rheumatoid arthritis. Morphological changes were evaluated on lateral cephalograms before and after surgery. Respiratory function and mandibular movement were assessed with the use of an apnea-monitor and an LED mandibular tracking device, respectively. After surgery, symptoms such as snoring and daytime sleepiness improved, and solid food could be masticated. Postoperative cephalograms showed that both the posterior airway space and ramal height were significantly improved by surgery. Postoperative records of mandibular movement indicated stability of the occlusion and improvement of mandibular movement, as compared with the preoperative records. Mean oxygen saturation significantly improved 1 month after surgery, whereas apnea and apnea-hypopnea indices did not change significantly.