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papillae from the tongue, and the early development of vascular problems are often associated with uncontrolled or poorly controlled diabetes mellitus.
Normal aging conditions and disease states in the oral mucosa have a profound effect on prosthodontic techniques. Reduced mucosal resiliency prolongs the time necessary for tissue recovery following denture wear. Periods of tissue conditioning must be extended and the number of hours of non-denture wear prior to making final impressions should be increased loss of tissue elasticity greatly magnifies the probability of overextending final impressions. Therefore, impressions must be made with a free-flowing material in an accurately border-molded custom tray. Tooth position and base contours should adequately support facial contours. Because of reduced tissue resistance to trauma and prolonged healing time, every effort should be made to improve tissue adaptation and occlusion at delivery. The patient must be instructed to remove the denture for at least eight hours per day. Tissue rest and massage with a soft toothbrush will aid in preventing further reduction of the already compromised blood supply. The patient should be advised against incising, particularly if an upper denture is opposed by natural dentition. Recall appointments should be scheduled on the basis of tissue health and anticipated rate of change-not on some empirical time period.
Although minor alterations in the bone structure of the residual ridge are not usually clinically detectable, rapid and gross changes should arouse suspicion of an underlying systemic problem. Local factors contributing .to bone loss include ill-fitting and underextended dentures, poor occlusion, and 24-hour wear. Aging changes within the neuromuscular system affect many aspects of prosthodontic treatment. Since learning new patterns of muscular activity may be difficult, major changes in occlusal patterns or tooth position should be avoided. Compromised neuromuscular control also contraindicates the use of precision attachments. Because good oral hygiene may be difficult to achieve, removable partial denture design should be as open and self cleansing as possible.
Decreased proproception, muscle trainability, and precision of mandibular movement make obtaining accurate interocclusal records difficult. The elderly patient may have problems performing precise movements and often cannot maintain desired jaw relations should be registered with very fast setting materials. Modeling compound is the preferred recording material because an acceptable record can be made with repeated gentle closures. Plaster or zinc oxide and eugenol both require that the patient hold a static position while the recording material sets-a difficult if not impossible task. Problems associated with record making also influence the choice of artificial teeth. If it is impossible to make lateral or protrusive records, balanced occlusion and cusped teeth should be avoided.
Because denture stability and retention are, to a large extent, a matter of control by the lips, cheeks, and tongue, neuromuscular problems may affect the ability to wear dentures successfully. Patients who lack precise control should always be advised that the adaptation process might be difficult and prolonged.
As might be expected, the age changes in the cells, fibers, and ground substances of the periodontium are similar to the connective tissue changes,