The most important characteristic of temporomandibular disorders is musculoskeletal pain, eminating from the temporomandibular joint and/ or the associated masticatory muscles. The most common temporomandibular disorders involve a balance disturbance of joint loading and the adaptive capacity of joint tissues. Etiological factors leading to such disturbance are largely unknown still. Most cases show an increase in intra-articular friction and associated mechanical joint disturbance. Future research efforts should focus both on factors affecting the adaptive capacity of joint tissue and on reducing their influence.