TMJ fractures in children: importance of functional activation of muscles in preventing mandibular asymmetries and facial maldevelopment.

Normal development of the mandible as well as some portions of the upper jaw and face are related to good function of the masticatory apparatus: the integrity and interaction of bony and soft-tissue structures may be highly disturbed by injury of the TM joints and result in facial and occlusal disharmonies. When the neuromuscular system is in harmony, the mandibular muscles collectively exert their effect on both position and movement of the jaw and the loading of forces on the TM joints is optimal and balanced. Unfortunately, TMJ fractures may alter completely this balance with loss of the support to the mandible against the temporal component and loss of the functional effect of the lateral pterygoid muscle on the mandible. Disturbances in the harmonious interplay of the masticatory muscles may result in facial alteration and asymmetries. If not treated, the dysplastic patterns of growth continues and worsens during the years.