Periodontal disease incidence

By Richard H. Nagelberg, DDS

There is a large survey of thousands of people that is undertaken periodically, and the data is used extensively for a wide range of studies. It is called the National Health and Nutrition Examination Survey (NHANES), and periodontal pocketing is among the parameters measured.

Previous estimates from the NHANES survey conducted from 1999 to 2004 indicated that 7% of the U.S. population between ages 35 and 64 had moderate to severe periodontal disease. The most recent survey, which concluded in 2010, revealed that 36.7% of the same population had periodontal disease! How did the disease incidence increase by more than five times in just a few years? It turns out that the method of data collection was the etiology of the vast differences reported. Periodontal examination in older NHANES surveys recorded probings from only two sites per tooth in only two quadrants, and probing sites were limited to buccal surfaces. In the most recent survey, which started in 2009, full-mouth probings using six sites per tooth were completed. What is the significance of these findings? NHANES data is commonly used in epidemiological studies. Research that used older NHANES data had incorrect conclusions since only one in five people with periodontal disease were identified; the rest were counted among the control group. More importantly, what does this mean for those of us in clinical practice?

With at least one-third of U.S. adults in the 35 to 64 age groups, the same proportion of patients in our practices should be having periodontal therapy and maintenance rather than prophies. The percentage of periodontal services being provided in the United States is less than half of 36.7%, which means a lot of periodontal disease is not being addressed. As importantly, older NHANES data attempted to identify relationships between periodontal disease and other systemic diseases. Results from studies using older data indicate the incidence of diabetes, stroke, and heart disease increased in the presence of periodontal disease. Failing to identify periodontal disease in 80% of those surveyed means these conclusions underestimated the associations between oral and systemic diseases. The magnitude of the problem in the oral cavity and beyond is greater, likely by a significant amount, than previous research indicated. Obviously research needs to confirm the extent of the associations, but at least we can have more confidence in the conclusions going forward.

From a practical perspective, the new data clearly indicates that the incidence of moderate to severe periodontal disease encountered in virtually every dental practice is much greater than we were previously led to believe. When reading research that uses NHANES data prior to the most recent survey, it would be prudent to carefully evaluate the conclusions and determine if you think they are accurate. More importantly, when patients present to our offices, we should understand that a large percentage of them has periodontal disease. Our efforts to identify clinical signs of disease should be diligent, making sure all cases of periodontal disease are diagnosed and treated. The importance of the new data is perhaps most relevant beyond the oral cavity. For example, in the 2004 NHANES survey, adults with diabetes were shown to be nearly three times more likely to have periodontal disease than nondiabetics. Studies based on the new data may show that diabetics are even more likely to have periodontal disease. Associations between periodontal disease and cardiovascular disease will likely show a stronger relationship as well, since older data only identified one in five individuals with periodontal disease rather than one in three.

The associations between the mouth and body have two mechanisms. One is the contribution to the total inflammatory burden from periodontal disease. The other is the direct effect of periodontal pathogens, including Porphyromonas gingivalis (Pg) and Fusobacterium nucleatum (Fn), among others, on vascular disease. The importance of bacterial identification will take on added importance going forward. Patients with a genetic predisposition to periodontal disease and patients with high-risk periodontal pathogens need to be monitored closely to prevent progression to periodontitis and potentially an increased risk for systemic events.

We should spend the lion's share of our time educating patients on the critical importance of biofilm control. Keeping the bacterial load as low as possible will increase the odds for great oral and overall health.

Richard Nagelberg, DDS, has practiced general dentistry in suburban Philadelphia for more than 30 years. He is a speaker, advisory board member, consultant, and key opinion leader for several dental companies and organizations, and he lectures on a variety of topics centered on understanding the impact dental professionals have beyond the oral cavity. Contact him at [email protected].