Well-intentioned half-truths

July 1, 2007
Back in the day when I was growing up, my sister, brother, and I would find very creative ways to alter the truth...

by Lynne H. Slim, RDH, BSDH, MSDH

Back in the day when I was growing up, my sister, brother, and I would find very creative ways to alter the truth, especially when my dad would ask the familiar question, “Who used the bathroom last and forgot to replace the toilet paper?” The easiest way to back out of answering the question was to pretend not to hear it (grab the headphones!), make believe I was sleeping, or say out loud, “Not me!” I might also say something like, “Kathy was in there last,” especially when I knew that my sister wasn’t home at the time to accuse me. Where there’s a will, there’s a way, the saying goes, and we were very creative in telling tall tales.

I owe it to my beloved dental hygiene profession to address a topic that I believe may have resulted in the delivery of well-intentioned half-truths that need some clarification. The oral/systemic link is a very popular topic in continuing-education courses. We are bombarded with new theories that link periodontal infections to various systemic diseases such as atherosclerosis, diabetes mellitus, rheumatoid arthritis and other immune diseases, pneumonia, obesity, premature births, developmental disorders in children, and even pancreatic cancer.1

A growing list of systemic links?

We now read about these oral/systemic links in various trade journals, consumer magazines, books, patient brochures, Web sites, and blogs. The movement has even resulted in oral health-care professionals telling patients about causal relationships between periodontal infections and a growing list of systemic diseases.

Try to imagine this scenario. A hygienist completes a periodontal exam on a pregnant patient and becomes alarmed when she discovers that the patient has a chronic, localized periodontal infection with 4 to 8 mm bleeding probing depths. Using a soft tone of voice, the hygienist gently touches the shoulder of the patient and proceeds to tell her that she is at greater risk of miscarriage and premature delivery due to the periodontal infection. Despite the patient’s obvious alarm upon hearing this shocking news, the hygienist goes on to say that this particular oral/systemic link has been proven and is well-documented in the dental and periodontal literature. To emphasize her point, she shows the patient a graphic picture from a magazine that illustrates oral bacteria entering the amniotic fluid of a fetus.

What do you think about this message? Is it one based on a growing body of scientific evidence that is indisputable and founded on an accumulation of studies, or is the message based on conflicting, inconclusive evidence and hearsay?

The results of a recent landmark study that appeared in the Nov. 2006 New England Journal of Medicine (the largest clinical research trial to date) were a huge disappointment to many oral health professionals who were absolutely convinced that this link was credible and worthy of dissemination to the general public. Scientists reported that women who received nonsurgical treatment for periodontal infection did not significantly lower their risk of delivering a premature or low-birth-weight baby.2 In addition, it was discovered that pregnant women can receive general dental care, including periodontal care, through the second trimester of pregnancy and that this care does not increase the risk of adverse events for women during pregnancy.

Over the last two decades, scientists have been busy identifying risk factors associated with premature births, and some have theorized that periodontal disease during pregnancy could be one of those elusive and less obvious risk factors.2 Results from earlier small-scale studies began to support this notion, but there is a need for larger, well-designed, randomized clinical trials that result in valid, reliable, and more easily interpreted data. In larger, well-controlled studies, the deliberate act of assigning pregnant women to experimental groups at random helped to control other risk factors for preterm birth, such as access to medical and dental care, smoking, poor nutrition, level of education, socioeconomic status, etc.

So, where do we go from here? First, it’s important to note that the U.S. National Institute of Dental and Craniofacial Research has funded another large study called the MOTOR study. The study is designed to determine which women with less severe periodontal infections are at risk of delivering preterm babies.2 Results from this study will be available in a couple of years, but in the meantime

let’s recognize the importance of optimum oral and general health during and after pregnancy without scaring our pregnant patients into compliance!

Back in the late 1970s, I studied research methodology under Professor Michele L. Darby, RDH, MS, at Old Dominion University in Norfolk, Va. Like many undergraduate students, I couldn’t figure out the relevance of this particular course at first. But it didn’t take Professor Darby long to pound into my head some very important messages about the significance of becoming a discriminating consumer of research findings and making sense of reams of data as we seek to maintain a truly “professional” role in serving the needs and desires of our patients.

Professor Darby co-wrote the very first textbook for hygienists and other oral health professionals on research methods, and I’ve never understood why this text wasn’t mandatory in every dental institution! How can we possibly separate infomercials and spin-doctoring from scientific evidence if dental and dental hygiene students don’t engage their minds in the study of research on a continual search for the unbiased truth?

Let’s take, for example, another oral/systemic link that we know more about. Diabetes is a disease that I have studied in recent years, but I do not claim to have any great expertise in this area. I surround myself with individuals who have developed an expertise in diabetes and who read relevant research reports.

I recently challenged myself to write a continuing-education course for Procter & Gamble on diabetes. My co-author was Cynthia Stegeman, RDH, MEd, a licensed dietitian and certified diabetes educator. Cindy never ceases to amaze me with her continuing thirst for breakthroughs in diabetes research. She has taught me that diabetes is much more than a disease. Instead, it is a group of metabolic diseases or a constellation of metabolic abnormalities. Cindy emphasizes that patients who tell us that their diabetes is just a “touch of sugar” are instead dealing with a systemic condition distinguished by abnormalities in the metabolism of carbohydrates, proteins, fats, and insulin.3

Even a diagnosis of prediabetes can indicate a lifetime of serious, long-term complications. Once diagnosed, diabetes can be managed over a lifetime, but it never goes away. In helping patients with diabetes achieve good oral health, it is imperative that hygienists understand the strength of the evidence behind the diabetes/perio link.

While writing the course, I scoured the periodontal research literature and found substantial evidence that individuals with poorly controlled diabetes have tremendous difficulty controlling bodily infections, including periodontal disease. I have read a lot of the longitudinal research on the Pima Indians in Arizona who received general health and periodontal exams every two years since 1965. What startled me initially when reading morbidity/mortality data was this statistic: nearly 60 percent of this particular adult Indian population studied had severe periodontal disease, and 70 percent of those with severe periodontal disease were edentulous!

What is a lot less clear to me is the claim by many periodontal researchers, dental authors, and public speakers that individuals with diabetes and periodontal disease have more difficulty controlling their blood glucose.

In reading an editorial by James R. Hupp, DMD, MD, titled “Expanding Oral-Systemic Linkages: Are We Putting the Cart Before the Horse?” I realized that I am not alone in questioning this portion of the diabetes link.1 Dr. Hupp mentions the possibility that individuals with diabetes might generally take poorer care of themselves, which may jeopardize the control of their diabetes and periodontium.

He also suggests, “It is premature to go too far along the path of alerting all members of society that we understand the linkages well enough to state that the causal relationship is firmly enough established to change public policy and to which to divert resources in lieu of other conditions with more scientific proof.”1 Dr. Hupp also states, “Dentistry must resist efforts to put the clinical practice cart before the research horse.”

I applaud his courage to speak openly about this growing movement, which he also describes as “developing a momentum of its own.” Patience is an important virtue as applied to these linkages, and it’s important that we continue to tell our patients the whole truth and not partial or craftily spun truths.

So, what do I tell my patients about the various oral/systemic links when they ask? As the linkages keep on growing and the news media continue to announce new ones, I still tell my patients this: An infection-free mouth is an achievable and worthwhile personal goal that leads to improved overall health and well-being. I believe that it is time to establish a culture of evidence-based dental hygiene practice that is free from outside influences and continues to seek the whole truth and nothing but the truth.

Lynne H. Slim, RDH, BSDH, MSDH, is a practicing hygienist/periodontal therapist who has more than 20 years’ experience in both clinical and educational settings. She is also president of Perio C Dent Inc. (Perio-Centered Dentistry), a practice-management consulting firm that specializes in creating outstanding dental hygiene teams. Lynne is a member of the Speaking and Consulting Network (SCN) that was founded by Linda Miles, and has won two first-place journalism awards from ADHA. Lynne is also owner/moderator of a periodontal therapist yahoo group: http://yahoogroups.com/group/periotherapist. She can be contacted at [email protected].


1 Hupp JR, ed. Expanding oral-systemic linkages: are we putting the cart before the horse? Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology 2006; 103(4):443-445.

2 National Institute of Dental and Craniofacial Research. News Release. Study finds periodontal treatment does not lower preterm birth risk. 11/1/2006. http://www.nidcr.nih.gov/NewsAndReports/NewsReleases/default.htm.

3 Slim LH, Stegeman CA. Diabetes: a multifaceted syndrome. Treatment considerations in dentistry. Online CE course: 12/11/2006. http://www.dentalcare.com.