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Not all-prosthodontic patients are old and not all-old people are prosthodontic patients. However, as life expectancy has improved, the number of geriatric prosthodontic patients has increased markedly. Since the changes of aging may greatly complicate dental treatment, the practitioner must strive to understand the psychological, anatomical, and physiological changes that occur. He must modify his approach and technique accordingly.
The general process of aging is not well understood. It has been described as both a normal physiologic phenomenon and as a pathological degeneration. Those who define aging as biologic, consider the process to be a genetically determined, inevitable termination of normal development.
The pathologic viewpoint regards aging as: (l) a destructive process possibly related to autoimmune reactions or (2) an accumulation of the effects of minor traumatic experiences, which occur throughout life. The argument over the inherent nature of aging is far from resolved. It is apparent, however, that many specific disease entities tend to amplify the degenerative changes associated with old age. It also appears that increasing age renders the body less resistant to pathologic change.
"Normal" physiologic processes for the elderly are difficult to describe. True physiological old age, free from disease, probably never occurs. However, certain trends in aging seem to be predictable. It is evident that regression in general body function begins at 25 to 30 years of age and continues to death. A decline in cellular metabolism leads to a reduced potential for cell growth and repair. The rate of cell division (mitosis) diminishes so that by the age 65, cellular depletion may approach 30%. Because all tissues, organs, and systems do not regress at the same rate have to the same degree, the composite body structure and function is considerably different in the aged person than in the young. Systemic and oral findings should be interpreted in relation to those that might be expected in a healthy individual of the same age. Treatment procedures must take into consideration the reduction of both physiological and mental adaptability.
Oral and perioral findings in the geriatric patient may be associated with the general aging process but are also frequently related to the presence of chronic disease and/or malnutrition. Assessment of aging changes must begin at the first contact with the patient and continue through the post-delivery adjustment phase of treatment. Patient education and treatment techniques should be designed to accommodate for not only changes present at the time of treatment but also those expected in the near future.
There is decreased thickness of both the mucosa and the submucosa and the elasticity of the connective tissue diminishes. Declining vascularity leads to poor tissue oxygenation and nutrition. The mucosa is increasingly susceptible to mechanical, chemical, and bacterial irritation. Healing time is prolonged. Many systemic problems or conditions may complicate the “normal” mucosal changes of aging. Generalized atrophy may be associated with a fall in estrogen output following menopause. Mucositis may be due to vitamin BI2 deficiency or radiation therapy. Vitamin C deficiency may lead to retarded wound healing, capillary fragility, and gingival bleeding and swelling. Gingival lesions, xerostomia, mucosal pyperemia, burning tongue and palate, loss of