Effects of Aging on the Mouth
With aging, the taste buds become less sensitive. Older people may find their food tastes bland so, for more taste, they may add abundant seasonings (particularly salt, which is harmful for some people) or they may desire very hot foods, which may burn the gums. Older people may also have disorders or take drugs that affect their ability to taste. Such disorders include infections in the mouth, nose, or sinuses; gum disease; mouth cancer; and chronic liver or kidney disease. Drugs affecting taste include some drugs used to treat high blood pressure (such as captopril), high cholesterol (such as the statins), and depression.
A modest decrease in saliva production occurs with age and can be decreased further by some drugs. The decrease in saliva causes dry mouth (xerostomia). The gums may get thinner and begin to recede. Xerostomia and receding gums increase the likelihood of cavities. Some experts also believe that xerostomia may make the lining of the esophagus more susceptible to injury.
Despite xerostomia and receding gums, many older people retain their teeth, especially people who do not develop cavities or periodontal disease, which is a destructive disease of the gums and supporting structures caused by the long-term accumulation of bacteria (see Introduction to Periodontal Diseases). Some older people lose some or all of their teeth and need partial or full dentures (see Dental Appliances). Tooth loss is the major reason that older people cannot chew as well and thus may not consume enough nutrients. When older people lose their teeth, the jaw bones that hold the teeth in place waste away (called senile atrophy).
As people age, teeth become worn and the muscles used for chewing become weaker, making chewing tiresome. Tooth enamel tends to wear away with aging, making the teeth vulnerable to damage and decay. Periodontal disease, however, is the major cause of tooth loss. Periodontal disease is more likely to occur in people with poor oral hygiene, in people who smoke, and in people with certain disorders, such as diabetes mellitus, poor nutrition, leukemia, or AIDS. Dental infections caused by bacteria can also lead to pockets of pus (abscesses) in the brain, cavernous sinus thrombosis, and unexplained fevers.