Study published in Journal of Dental Research demonstrates value of genetics in preventing periodontal disease

The study explored the influence of three key risk factors for periodontal disease — smoking, diabetes, and genetics — on tooth loss given varied frequencies of preventive dental visits that included cleanings. By examining claims data from 5,117 patients without periodontitis throughout a 16-year period and conducting genetic testing, researchers determined that patients with genetic variations of the IL-1 genotype, or one or more other risk factors examined, were at significantly increased risk for tooth loss and therefore require more preventive dental care. The IL-1 genetic variation was the single most prevalent risk factor — nearly one in three Americans carry this genetic variation. This study demonstrates the important opportunity to provide more effective preventive oral care through the use of risk-based patient assessment that includes genetic testing.RELATED |Divaris, others confirm genetic link to periodontitis through first genome-wide studyHighlights of the study, “Patient Stratification for Preventive Dental Care” can be found in full here. • Explored the frequency of preventive dental visits (dental cleanings) in adults and the role of three key risk factors: smoking, diabetes, and genetics in the progression of periodontal disease leading to tooth loss • Stresses the importance of dental visits to diagnose the disease before symptoms present • Findings represent how genetics can be used to prevent a disease that is very prevalent, costly, and preventable. • For patients with one or more risk factors — categorized as high risk — the traditional two dental cleanings per year had significantly greater value than one cleaning in preventing tooth loss • For high-risk patients with two or more risk factors, two cleanings per year did not appear to be sufficient to adequately prevent tooth loss, suggesting three or even four cleanings per year may be beneficial, and cost-effective, in reduction of tooth loss Research was conducted under the direction of Dr. William Giannobile, Najjar endowed professor of dentistry and biomedical engineering, and chair of the Department of Periodontics and Oral Medicine at the University of Michigan.RELATED |What's left to learn about the oral-systemic link? Periodontitis is a bacterially induced chronic inflammatory disease that destroys the bone and gum tissues that support the teeth. It is one of the most common chronic diseases of the body. It causes bleeding and swelling of the gums, loose teeth, bad breath, and can ultimately lead to tooth loss. Severe periodontitis has been associated with increased risk for multiple other diseases, including cardiovascular diseases, diabetes, and rheumatoid arthritis. One in four Americans over age of 65 have lost all their teeth.RELATED |Blood in the sink: How the relationship between oral and systemic health is gaining momentum – and what dentists need to know, part IRELATED |Blood in the sink: How the relationship between oral and systemic health is gaining momentum – and what dentists need to know, part II “Dentistry has long been a leader in the delivery of preventive health care to patients. The findings of this study provide dental clinicians with the opportunity to offer personalized, preventive care that is based on new insights into the importance of genetic risk factors,” said Dr. Kenneth Kornman, chief executive officer of Interleukin Genetics, which developed the genetics test used in the study. “Personalized medicine is an important frontier in health care driven by the clinical application of genetic and molecular information. Genetic-based risk assessment has long promised to improve prevention and treatment of chronic diseases,” said Sir Gordon Duff, professor emeritus of Molecular Medicine the University of Sheffield and co-author of the paper. “The findings of this study represent perhaps the first broad-scale application of genetics to help prevent a disease that is very prevalent, costly, and preventable.” Periodontitis initiation and progression is driven by two factors: bacterial plaque that initiates the disease and the body’s inflammatory response to bacteria which, when overly aggressive, causes breakdown of the bone and tissue that support the teeth. This inflammatory response varies greatly within the population and is significantly impacted by individual genetic makeup. Genetic testing can identify patients who have an increased inflammatory response to oral bacteria which significantly increases risk of periodontitis and tooth loss. Smoking and diabetes also contribute significantly to the risk of periodontal disease. “Ultimately, patients should be evaluated by their dentist regularly and receive needed preventive care before any symptoms of periodontal disease appear. This disease can result in disfiguring bone loss around teeth and has been implicated as a risk factor for multiple systemic conditions that benefit from early stage prevention,” said periodontist Donald S. Clem, III, DDS, diplomate, American Board of Periodontology, past president of the American Academy of Periodontology. “Historically, we have lacked the prognostic tools to effectively identify patients at greatest risk for periodontitis. This study underscores the need to adopt a genetic, risk-based approach and gives patients a compelling new reason to visit the dentist for a comprehensive periodontal evaluation. As we see with other chronic diseases, identifying and understanding genetic predisposition to disease is a critical component of long-term prevention." When Dr. William Giannobile, chair of the Department of Periodontics and Oral Medicine at the University of Michigan School of Dentistry in Ann Arbor, was asked what, in his opinion, is the most surprising result that came from this study, here’s what he said …

We were surprised to see how the risk factors separated out so well the tooth loss rates in almost a dose-response manner. Meaning, as the numbers of risk factors increased, the tooth loss rates increased. We knew smoking, diabetes, and genetics were important, but we were intrigued to see that when the risk factors were coupled together, increased rates of tooth loss occurred. Of the patients with two to three risk factors who lost the most teeth, 66% of the total patients were genotype positive smokers.

Do you believe that genetics will become an even greater factor in planning dental treatment for the future, particularly in regard to periodontitis? And if so, how?

Indeed, we know that genetics contributes to about half of the driving force of periodontal disease severity, with the other half coming from the composition of the bacterial flora. The IL-1 genotype is the most well-studied genetic risk for disease, and based on our study plays a role in the treatment-planning process in terms of risk assessment. We know that the complexity of periodontal disease as a polygenic disease (like heart disease) is controlled by many genes. Our study is an example of using one gene in risk assessment. It is likely that periodontal disease is controlled by at least dozens of susceptibility genes. In the future we will be able to use "signatures" of gene sets and infecting bacterial pathogens to determine patients' disease status and potential response to our battery of therapies available for periodontitis.

We also spoke with Donald S. Clem, III, DDS, diplomate, American Board of Periodontology, past president of the American Academy of Periodontology, and asked him what, in his opinion, is the best way dentists and their teams can motivate patients to make oral health a priority.

I believe the answer to motivating patients to make oral health a priority is to make sure all dental team members have a patient-centered approach to care. The patient needs to feel that they are cared for as individuals. This begins with the new patient being welcomed by the office and being seen by the doctor for a comprehensive review of their medical and dental histories, an examination of the extraoral and intraoral structures, the teeth, and a comprehensive periodontal evaluation.

While this seems elementary, we must not forget that besides being the standard of care, this first visit with the doctor provides us with the opportunity to personalize the patient's condition and make important risk assessments. For example, if my patient has diabetes, I will talk to them about their increased risks for periodontitis and also cardiovascular disease. We'll also discuss how they monitor their glycemic control, how they’re feeling, and how often they visit their physician. Patients need to understand that their teeth are connected to the rest of the body and emerging evidence is demonstrating that oral disease has increasing associations with other systemic diseases.

When we have these kinds of discussions with our patients, they understand that we care about them as individuals, we understand their life challenges, and we can say with more confidence than ever that we will design a treatment plan and recall schedule specifically designed to keep them healthy. They then begin to view their dental health as part of their overall health and well being.

For additional details, the study “Patient Stratification for Preventive Dental Care” Giannobile et al. 2013 from Journal of Dental Research, can be accessed here.

About Interleukin Genetics, Inc.
Interleukin Genetics, Inc. (OTCQB: ILIU) develops and markets a line of genetic tests under the Inherent Health®and PST® brands. The products empower individuals to prevent certain chronic conditions and manage their existing health and wellness through genetic-based insights with actionable guidance. Interleukin Genetics leverages its research, intellectual property, and genetic panel development expertise in metabolism and inflammation to facilitate the emerging personalized health-care market. The company markets its tests through partnerships with health and wellness companies, health-care professionals, and other distribution channels. Interleukin Genetics’ flagship products include its proprietary genetic risk panel for periodontal disease and tooth loss susceptibility sold through dentists and the Inherent Health Weight Management Genetic Test that identifies the most effective diet and exercise program for an individual based on genetics. Interleukin Genetics is headquartered in Waltham, Mass., and operates an on-site, state-of-the-art DNA testing laboratory certified under the Clinical Laboratory Improvement Amendments (CLIA). For more information, please visit www.ilgenetics.com.