By David A. Albert, D.D.S., M.P.H.
Columbia University College of Dental Medicine

How often should you visit the dentist?

Our parents told us to visit twice a year. Many years ago, an advertisement said you would not get cavities if you used a popular toothpaste and visited the dentist twice a year. Today, insurance typically pays for two dental visits and cleanings each year. If you ask your dentist or dental hygienist, you probably will get the same advice — come in two times a year.

It appears, then, that professionals, insurers and parents overwhelmingly support two dental visits a year to take good care of your teeth and gums. The correct answer, however, is that the number of visits you need varies for each person. What has happened to change the traditional advice?

First, we know more about the two most common dental diseases, cavities and gum (periodontal) disease. The last 50 years or so have brought major changes in dental health. Toothpaste now contains fluoride. Water supplies in many areas also are fluoridated. As a result, we have seen a huge drop in the number of cavities in this country.

There also has been a change in how long it takes for cavities to develop. How is that possible?

Cavities form when bacteria eat sugars and produce acid. The acid breaks down the tooth to form a cavity. Before we had fluoride in our toothpaste and water supply, cavities grew fast. They often would become very large in less than six months. Visiting the dentist often was very important. The dentist could find a problem early and fix it with a small filling before a major problem occurred.

Today we get fluoride from many sources. It is in toothpaste, mouth rinses, water and even in our foods. Fluoride changes how we get cavities. Fluoride becomes part of the tooth and makes it stronger. The bacteria that cause cavities are not able to attack and break the tooth quickly.

Studies have shown that it now takes longer, in most cases at least two years, for a cavity to form. Even if you visit less than twice a year, your dentist will be able to find cavities when they are still small.

Our understanding of periodontal or gum disease has also improved. Periodontal disease is a long-term (chronic) disease. If not treated, it will get worse as we age. Untreated, this disease will damage the bone that holds your teeth in place. Your teeth can get loose or even fall out.

Your dentist needs to examine you to assess the health of your gums. But for most people periodontal disease gets worse very slowly. It can be diagnosed early even if you visit the dentist less than twice a year.

If cavities and periodontal disease get worse slowly, how often should you visit the dentist?

The answer depends on your examination and overall mouth conditions. During an exam, your dentist will assess whether you have any problems. He or she will ask about your eating habits, oral health habits and overall health.

Diseases of the body, such as diabetes, can affect your teeth and gums. People with diabetes tend to have more gum disease than people without diabetes. They also tend to develop cavities more quickly. People with diabetes should therefore visit their dentist more frequently.

Many medicines can also affect your mouth. For example, people with epilepsy often take a drug called phenytoin (Dilantin) to prevent seizures. Dilantan can cause the gums to grow too much. Because of this, people who take Dilantin should visit the dentist more often.

Many high blood pressure medicines tend to cause dry mouth. Someone with a dry mouth will be more likely to get cavities and periodontal disease. These diseases also will get worse faster if you have a dry mouth.

Smokers also have more dental problems. They have more gum disease. They also can develop sores or lumps in their mouths that can turn into cancer. Smokers should visit the dentist more frequently.

After reading this, you are probably unsure of how often you should visit your dentist and dental hygienist. The answer, again, is that it depends on your exam.

For most people with a healthy mouth, recommending a once-a-year visit to the dentist is appropriate. An example would be someone with no signs of periodontal disease or cavities within the last two years.

Using a "one size fits all" approach and recommending that all patients visit the dentist twice a year is definitely outdated. Your dentist will examine you, consider your dental and medical history, and then suggest how often to visit. In deciding your dental visit frequency, one size does not fit all.

David A. Albert, D.D.S., M.P.H., is an associate professor and associate director of community health at the Columbia University College of Dental Medicine. He also holds an appointment in the Joseph Mailman School of Public Health at Columbia University. He maintains a practice within the ambulatory care network of the Columbia DentCare program in the community of Washington Heights/Inwood in Northern Manhattan.