This project examines the status of various oral tissues during physiologic aging. The current emphasis is to study cross-sectional and longitudinal effects of aging on oral physiology in a variety of populations: healthy whites and blacks of different ages, patients with Alzheimer's disease, and perimenopausal females. Healthy whites are being followed in two studies, at the Clinical Center in Bethesda, MD. and at the Baltimore Longitudinal Study of Aging (BLSA) in Baltimore, MD. Healthy, community-dwelling blacks are being studied in a collaborative study with Howard University Dental School. Perimenopausal females and patients with Alzheimer's disease are also being followed at the Clinical Center at NIH. The influence of systemic disease and its treatment on aging and the oral cavity has become an important focus in our investigations. For example, a study of the effects of glucose metabolism on oral physiology and aging is underway using the BLSA population. Clinical evaluation of healthy participants involves an oral health questionnaire, collection of unstimulated and stimulated parotid and submandibular gland salivas, a comprehensive examination of dental, periodontal, and mucosal tissues, an oral motor exam, and the determination of pressure, gustatory, and olfactory sensitivities. An additional study was initiated in the BLSA protocol utilizing an instrument designed to measure maximum tongue pressure and tongue endurance capability. During this reporting period, results from cross- sectional studies suggest that impaired glucose tolerance and diabetes have no observable effects on salivary gland function. Cross-sectional studies on unmedicated patients with Alzheimer's disease suggest that their oral health is indistinguishable from age-matched controls with the exception of specific changes in salivary gland function and gingival health. Results from longitudinal studies in healthy individuals of different ages reveal that stimulated parotid salivary gland flow rates are unchanged over 10 years.
