Modern dentistry and dental technology services involve caring for patients throughout life, with dentists and technicians performing the following functions:
Given the right cleaning materials (toothbrush and toothpaste) and appropriate brushing technique, it is possible to clean the teeth properly. A simple scrubbing technique will not achieve satisfactory cleaning and can cause damage to the gums and dental hard material (wedgeshaped defects). Therefore, a systematic approach to
cleaning the teeth is essential.
Oral hygiene has the following functions (Fig 9-15):
The development and progression of inflammatory
periodontal diseases are dependent on:
Caries is the most common dental disease. If the individual it affects is suitably predisposed, caries destroys the dental hard tissue by a chemicoparasitic process. Caries starts on the surface of the tooth, usually in the enamel of the dental crown (initial caries) or on the exposed cementum at the neck of the tooth (caries of cementum), and it goes on to attack the dentin.
The number of teeth changes depending on the course of exfoliation in that individual. Normally the primary dentition consists of 20 teeth, and the permanent dentition contains 32 teeth. However, the number of teeth present at any particular moment during exfoliation will not always correspond to the standard number. Part of an orthodontic examination is to establish whether any anomaly exists and its severity.
Developmental anomalies and structural defects (tooth dysplasias) are commonly found in individual teeth as a consequence of genetic or infectious factors, vitamin deficiency diseases (eg, rickets), or certain medications (eg, tetracycline or antibiotics). Because the development of the teeth takes place over very extended periods of time (from the fifth week of embryonic life through to the age of 16 years), during which time many events may intervene directly or indirectly in this process, the teeth often show traces of disorders and structural defects. The results are structural flaws, deviations in tooth size and shape, and abnormal numbers of teeth (Fig 9-4).
The development of the jaw starts around the end of the third week of embryonic life. The normal development process can be interrupted by malformations due to inhibitory factors, by which palatine tori do not develop fully and fail to fuse together in the midline.
Pathology of the orofacial system concerns developmental anomalies and their consequences, disease processes, and the course of diseases. It involves investigating the causes (etiology), physical changes (pathologic anatomy), and origin (pathogenesis) of diseases as well as their clinical appearance (signs and symptoms).
The condylar paths are set in fully adjustable articulators after the tracks of the condylar paths have been traced and measured or by using eccentric positional records (interocclusal records).