The Inflammation Connection

New evidence suggests a link between chronic inflammation and disease that may revolutionize modern health care, and dentistry plays a key role. Normally, inflammation defends the body against infection, keeping us healthy in spite of daily contact with a variety of pathogens. However, the body’s inflammatory response can go haywire due to a variety of causes from genetic disposition to smoking. This out of control response results in chronic inflammation and its effects appear to be devastating to our health. This new research, which is currently circumstantial, points to a direct link between chronic inflammation and the development of serious diseases like cardiovascular disease, Alzheimer’s disease, diabetes, and cancer.

This link was discovered by Paul Ridker, MD, a cardiologist at Brigham and Women’s Hospital in Boston, who was investigating the connection between cardiovascular disease and chronic inflammation. After finding that not all the men in the study sample who experienced heart attacks had high cholesterol, he had a hunch that chronic inflammation played a role. He decided to use a blood test to measure the level of inflammation in men who had suffered heart attacks. C-reactive proteins (CRPs), which are produced by the liver in response to inflammation, were the marker he chose as the measurement. The results were dramatic—men with elevated levels of CRPs in their blood were three times more likely to experience a heart attack than those with lower CRP levels. Studies done on women have found that women with high levels of CRPs seem to be at an even higher risk.

Numerous research studies are in progress to further understand the role of chronic inflammation in disease. In the meantime, pharmaceutical companies are rushing to develop drugs that specifically block inflammation. Researchers are not prepared to make specific treatment recommendations yet.

However, one thing is clear—good oral hygiene is imperative to limiting the damaging effects of chronic inflammation. Dental hygienists, as the facilitators of preventive dental health, are important players in the battle against chronic inflammation. As such, understanding the relationship between inflammation, CRPs, and the dental patient is integral to the efficacy of the dental hygienist in the effort to improve clients’ oral and general health. —Dimensions of Dental Hygiene

What is the relationship between chronic inflammation in gum tissues and elevated CRP levels?

Periodontal disease has been associated with elevated CRP levels and this may explain the mechanism by which periodontal disease is connected to a higher incidence of heart disease, because elevated CRP levels are associated with a higher risk of heart disease. We don’t know if gingivitis is related to higher CRP levels, but we do know that periodontitis is. Periodontitis is defined as pocket depth, attachment loss, and bone loss.

We don’t know if treating periodontal disease makes a difference. But it is likely that periodontal disease results in elevated CRP levels, which then contribute to a higher risk of heart disease.

Describe the link between heart disease and periodontal disease.

There is an inflammatory link but periodontal disease is an infectious link. There are four infections that are related to heart disease: chlamydial pneumonia, Helicobacter pylori gastric ulcer, cytomegalovirus (CMV), and periodontal disease. Inflammation is the mechanism by which these infections are related to heart disease. There is a relationship between periodontal infection and heart disease that may be explained by the CRP. CRP levels are elevated in these other infections also. These infections create an inflammation that causes the liver to produce a higher amount of CRPs.

There is an association between periodontal disease, specifically periodontitis, and heart disease of the atherosclerosis type. This association does not prove causality. Whether treating periodontal disease in patients at risk for heart disease or those with heart disease affects their heart disease at all has not yet been proven in studies. We don’t know if flossing and good oral hygiene—basically the prevention of periodontal disease—actually prevent heart disease. The association between periodontal disease and heart disease is a good reason to practice good oral hygiene and to prevent periodontal disease. However, you cannot tell patients that scaling and root planing and good oral hygiene will have any effect on heart disease at all. But on the positive side, these good oral hygiene practices will save their teeth!

Scaling and root planing cause an inflammatory response that is part of the healing process. During the inflammatory response, is there an elevation of CRP levels during the healing phase?

Several studies have shown that after scaling and root planing, patients’ CRP levels go down. An elevation does occur during the first few weeks but eventually at 3 to 6 months and 1 year, CRP levels go down. A short spike in CRP levels doesn’t really contribute much to heart disease. It’s the chronic elevation over years that most likely contributes. Common practice tells us that people don’t keel over with heart attacks after a scaling and root planing appointment, which doesn’t mean that this never happens, but it is unlikely. And we do know that eventually, 3 or 4 months postperiodontal therapy, patients will experience lower CRPs.

Is it possible that patients who have chronic inflammation somewhere else in their bodies will experience a lower level of CRPs when their periodontal disease is treated?

That’s what makes these findings even more amazing. People who have pneumonia or other systemic infections when their periodontal infection is treated will experience a decrease in their CRP levels. There are many infections contributing to elevated CRP levels and periodontal disease must be an important contribution to elevated CRPs because when treated, CRPs go down. When you consider that some patients have pocketing over most or all their teeth, the total ulcerated area is equivalent to the size of your hand. We have considered periodontal pockets a “little problem” for too long.

What other systemic diseases are adversely affected by periodontal disease?

There are many systemic effects of periodontal disease For example, diabetics with periodontal disease have less blood sugar control but when treated, blood sugar control improves. There is some strong evidence that periodontal disease increases the risk of low birth weight in pregnant women. There is also a relationship between periodontal disease and lung infections. In this instance, it is probably caused by aspiration of the bacteria from the periodontal pockets. Even though we don’t have all of the information on heart disease, if you’re diabetic, if you’re pregnant, or if you have abnormal respiration, periodontal disease could cause increased adverse effects.

Performing a periodontal health assessment examination is becoming more and more critical. What is the recommendation for probing?

For the general practice patient, probing should be done every 6 months or at each recall visit. If a patient is coming in for a series of restorative appointments probing is not necessary at each appointment as long as a good initial probing is done. In a patient who already has periodontal disease, we should reprobe every 3 months after therapy because recurrence of pockets can happen in 3 to 6 months.

During every recall visit the hygienist should probe and record the data and perform oral hygiene instruction, and participate in the recommended treatment. Hygienists carry out about 90% of periodontal therapy in the mild to moderate cases with major responsibilities in both initial instruction, monitoring, and in risk modification, such as smoking cessation.

Good technique and careful assessment should be used in probing and if there is any question, the dentist should be involved to decide on how the probing is done, how many sites, what kind of pressure, and how to best record the data.

From Dimensions of Dental Hygiene. May 2004;2(5):14-17.