The orthodontic standard of care

Orthodont i s t s have always been concerned with decisions to render the best and the most proper care for the individual patient. The decisions for the treatment, the treatment planning, and the treatment goals are based on a variety of factors. These factors include the type of malocclusion, the patient's age, growth and eruption of the teeth, facial growth in consideration with facial esthetics, dental stability, and function of the dentition. The treatment decisions are made on the basis of the scientific data, the resolution of the patient's records into a proper diagnostic analysis, and the establishment of clinically obtainable treatment goals. Also playing a part in the diagnostic decision are cooperation of the patient and the expertise and judgment of the orthodontist. Many treatment decisions are planned through the results gained in case reports, long-term research, and investigative literature. Often animal models are used to clarify the behavior of hard and soft tissues and to disclose the anticipated biomechanical results with various mechanisms. Because animal studies alone do not tell the whole story, experiments on human subjects, in selected cases, are used to verify the results. The biology of the stomatognathic system, the histologic changes in bone brought about by mechanical forces, the cellular processes that permit the movement of teeth, and the effects of growth on dental relationships have been well documented. Research in these areas continues at the molecular level. The literature reveals that interstitial elongation of bone does not occur and is contrary to the basic concept of bone biology and growth. The method of bone growth and apposition, resorption, and stimulation is true of the mandible and alveolus as it is of any other bone in the body. Excellent texts and manuals, reviewing the development, remodeling, growth, apposition, deposition, and resorption of bone, exist and are well documented with data gleaned from research. Bone reacts as a plastic support to the dentition. Alveolar bone is reactive in a precise and limited way, depending on the soft tissue envelope and the gradient of muscular forces. Since the alveolus is dependent on the teeth and is limited by basilar bony support, a balance and harmony