Dental Hygiene

Dental hygiene refers to the care of the teeth and other mouth tissues to keep them healthy and free of disease. These other mouth tissues are the gingivae, or gums, and the periodontium, the tissue that immediately surrounds each tooth and attaches it to the gums and the underlying bone. The teeth, gums, and periodontium are subject to a variety of diseases and disorders, the most widespread of which are dental decay and periodontal disease.

Dental decay, which is also known as dental caries, is probably the most common human disorder, affecting more than 95% of the population of the United States alone. It is caused by the formation of acid by certain mouth bacteria and is directly related to the eating of sweet and starchy foods because these bacteria thrive on refined sugars and starch. Colonies of these acid-forming bacteria often become concentrated in the crevices between the teeth and in the natural pits and fissures on the chewing surfaces of the teeth. They are also found in dental plaque, the yellowish-white material that collects on the teeth surfaces.

When sweet or starchy foods are eaten, any particles that remain in the mouth are acted upon by bacteria, and the acid they produce dissolves the hard enamel coating of the teeth. Once the enamel is penetrated, the decaying process is speeded up because the bacteria then feed on the organic material of the inner portion of the teeth, the substance known as dentine. In addition, the hole, or cavitation, in a tooth becomes a protected cistern for the accumulation of more food, bacteria, and acid.

Periodontal disease results from chronic irritation of the gums and periodontum, and its advanced form, called pyorrhea, is the chief cause of tooth loss in adults. The major cause of most cases of periodontal disease is the accumulation of dental plaque on the teeth. If it is not removed, the plaque hardens into a calcified material known as dental calculus, or dental tartar. Most dental plaque can easily be removed by adequate toothbrushing, but once it becomes dental tartar, it can only be removed by a dentist or dental hygienist.

In addition to dental plaque, other factors may lead to periodontal disease. These include large decayed areas of the teeth; broken teeth; excessive grinding of the teeth; biting on hard objects such as pencils, pipe stems, or bobby pins; poorly fitting or worn-out partial dentures; and defective fillings or crowns.

Proper Dental Hygiene Measures

A successful program of dental hygiene is aimed at preventing dental caries and periodontal disease through regular toothbrushing, proper eating habits, and the use of flouridated water and other flouride-containing substances. It also includes a regular schedule of dental checkups.

Proper Eating Habits

Good dental hygiene begins with choosing a well-balanced diet and restricting the consumption of those foods that are especially conducive to dental decay. Because sugars and starch are the main source of food for the acid-forming bacteria in the mouth, it is important to avoid foods that are rich in these substances. Prime examples of such foods are richly filled pastries, doughnuts, coffee cake containing preserved fruits, peanut butter, and cakes and pies with heavy sweet icing. These foods are particularly harmful because they tend to stick to the surfaces of the teeth. Other foods that are conducive to dental decay are sweetened canned fruits in heavy syrup, sweetened fruit juices, and citrus-flavored candies. Carbonated beverages, chewing gum, and breath sweeteners are also likely to cause dental decay, not because they contain large amounts of sugar but because they are used so frequently. Foods, drinks, and chewing gum that are artificially sweetened do not contribute to dental decay and should be used whenever possible to replace products containing refined sugars.


Regular brushing of the teeth using the correct method is the next important factor in good dental hygiene. It is extremely important to brush the teeth soon after every meal or snack so that any food particles trapped between the teeth or in the natural pits and fissures on the chewing surfaces can be removed. Brushing also prevents the accumulation of dental plaque on the teeth, and by removing food particles, it also helps prevent halitosis, or offensive breath. However, halitosis may also be caused by extensively decayed teeth, infections of the tonsils, sinuses, or throat, or the eating of certain types of foods, such as onions and garlic. Although mouthwashes may mask bad breath, they usually cannot cure the underlying cause, and if a rigorous program of home dental care does not correct the disorder, a dentist should be consulted.

Although brushing after every meal and snack is essential for good dental hygiene, it is equally important that the correct method of toothbrush-ing be used. When brushing the cheek and tongue surfaces of the teeth, the bristles of the toothbrush should move in an up-and-down direction. This action assures the movement of the bristles into and through the crevices between the teeth. When brushing the chewing surfaces of the teeth, a back-and-forth motion should be used. Automatic toothbrushes are engineered to produce an up-and-down movement, allowing the bristles to move over and between the surfaces of the teeth. Although hand brushing is as effective as using an automatic toothbrush, the use of an automatic toothbrush is sometimes recommended for small children and the handicapped.

Although brushing the teeth with only a toothbrush and water is effective in removing food particles, many people prefer the taste of toothpaste or powder, and some dentifrices containing fluorides are known to help prevent dental decay. In addition, toothpastes and powders contain abrasives that help remove dental plaque and stains. Most dentifrices also contain sweetening agents, but those products that contain sugar as the sweetener should be avoided.

After brushing the teeth, it is important to look in the mirror for dental plaque or food particles that may have been missed by the toothbrush. If necessary, brush the areas again or use dental floss or a toothpick to carefully remove the stubborn particles. Water-flushing devices that emit a jet of water for removing particles from between the teeth and just under the gums are very helpful for people with periodontal disease but are generally not recommended for others.

The care of dental appliances, such as dentures, bridges, and orthodontic appliances, is similar to that for natural teeth. Removable appliances should be taken out of the mouth and cleaned thoroughly with a special brush after every meal and snack. If it is not convenient to clean the appliance thoroughly, it should at least be rinsed with running water to remove food particles. Once or twice a week the appliance should be soaked for a few hours or overnight in a weak solution of sodium hypochlorite. This chemical, which is available in drugstores without a prescription, helps remove stains.

Use of Fluorides

The fluoridation of water supplies has been demonstrated to be a safe, relatively inexpensive public health measure for the prevention and control of dental decay and the other dental disorders that follow in its wake. The U.S. Public Health Service, along with the World Health Organization and many other health agencies, recommends that the fluoride content of water supplies be adjusted to one part of fluoride per every million parts of water. This amount of fluoride in the drinking water has been shown to reduce dental decay by as much as 66% and thereby reduce the cost of dental care by more than 50%.

In addition to drinking fluoridated water, there are three other ways in which a family or an individual may receive the benefits of fluorides. A fluoride pill to be dissolved in the home water supply may be prescribed by a doctor or dentist, and a fluoride solution may be applied directly to the teeth by a dentist or dental hygienist. The daily use of a fluoride toothpaste that has been approved by the Council on Dental Therapeutics of the American Dental Association is also effective in reducing dental decay.

Professional Care

Regular visits to the dentist, starting around the age of three and continuing every six months, is another requisite for good dental hygiene. Using special abrasives, the dentist cleans the teeth thoroughly, removing any dental tartar that has formed. Even for people who wear full or partial dentures a semi-annual checkup is important because dental tartar can form on artificial teeth as easily as it can form on natural teeth.

During a dental checkup the dentist may also take X-rays of the teeth to determine if any cavities are present. X-rays are also helpful in determining if there is a gum infection or a disorder of the bone supporting the teeth. Impacted teeth (those that are in an irregular position and cannot emerge properly) can also be seen on X-rays.