The Neglected Phase in Orthodontic Diagnosis and Treatment

The successfully corrected dental malocclusion is usually described as one that is excellent in appearance, excellent in function and stable or permanent in result. These are indeed the objectives that are desirable, but they are in a sense, somewhat intangible at least insofar as the exactness of the evaluation is considered [1]. The phrase form and function reflects a concept of interrelating the shape or attributes of something with its function. In dentistry the phrase may indicate the entire masticatory system acting as a biomechanical engine for the reduction of food [2]. For some clinicians the general principle that becomes operant is form follows function, meaning for examples include the dependant relationship between esthetics and optimum occlusion [3] physical forces and the periodontal ligament [4] arch form and beta function [5] and the controversial relationship between the morphology and function of the disco-muscular apparatus of the human temporomandibular joint. The masticatory system is a functional unit composed of the teeth; their supporting structures, the jaws; the temporomandibular joints; the muscles involved directly or indirectly in mastication (including the muscles of the lips and tongue); and the vascular and nervous systems supplying these tissues. Functional and structural disturbances in any one of the components of the masticatory system may be reflected by functional or structural disorders in one or more of its other components [6]. However, there is a lot of evidence that the masticatory system has ability to the wide range of adaptive modalities. These adaptations can be functional and/or structural and may respond to transient and/or permanent demands. Therefore, this system, like any biological system, cannot be viewed as a rigid and immutable [7]. Knowledge of how the mandible moves during mastication has greatly influenced procedures in clinical dentistry. Historically, an understanding of mandibular movement was considered important in removable prosthodontics. Later, this information was used in the design and setting of articulators, and in the design of the dentures and denture teeth themselves. Today the importance of jaw movements has become apparent in fixed prosthodontics, periodontics, orthodontics, and in the diagnosis and treatment of pain disorders of the masticatory system [8,9]. In regard to the occlusion of the teeth there are two concepts to be recognized the first is the morphological or anatomical concept, as the name implies this is an occlusion based on the forms of the teeth while the second is the physiologic concept. The physiologic occlusion is a living-dynamic as it participates as one of the components of the masticatory system. Abnormal functional relationship of the teeth may vary in degree of abnormality from mild to extreme. In the first instance certain teeth may occlude slightly in advance of the other teeth. This is premature contact of the teeth. This condition may also exist in the functional movements of the mandible during mastication [1]. In this paper the light is thrown on one of fundamental aspects in orthodontic diagnosis and treatment that is function by presenting a clinical case which is demonstrating the importance of this phase in orthodontic diagnosis and treatment.