In regard of the Neuro-muscular Physiology rules, closing reflex and avoidance reflex are not the same and opposite. In muscular physiology, we learn that all muscle must pass through a relaxation phase which lasts at least as long as the muscle activity phase. Each phase of relaxation permits metabolic regeneration of the muscle. In the case of muscular adaptation to occlusal interference, the phase of muscle relaxation is cut short, to the detriment of this metabolic regeneration. There is as a consequence, an accumulation of lactic acid within the muscle, the lactic acid induces the symptoms of muscle cramp.
All muscle cramp is painful.
Consequently, orthodontic treatment must also respect this relaxation phase of muscle physiology. Aesthetic dentistry and Masticatory Function . Aesthetics are a major preoccupation for our patients. Orthodontists define aesthetic criteria through which they choose between diverse appliances, both fixed and removable. According to the complexity of the treatment demands, the intervention of other medical specialities and maxillo-facial surgeons is sometimes required.