Richard H. Nagelberg, DDS
A substantial portion of the research illuminating the relationship between the mouth, the "bugs," and the rest of the body is being published in medical journals. This does impugn the reputation and credibility of peer-reviewed dental journals, but it is revealing nonetheless.
The November 2014 issue of Current Cardiology Reviews (Curr Cardiol Rev. Nov. 2014;10(4):355-361) contains a study that states: "Cardiovascular diseases are the leading cause of deaths. Also, cardiovascular risk factors start the atherosclerotic process, which leads to cardiovascular diseases. Nowadays, periodontal disease can also be considered another cardiovascular risk factor. It involves inflammatory, immunological, and humoral activities, which induce the production of proinflammatory cytokines and the destruction of the epithelium. This allows the entry of endotoxins and exotoxins in the bloodstream, which may contribute to atherogenesis and thromboembolic events. There is also direct invasion of the vessel wall by oral pathogens, triggering an inflammatory response that produces endothelial dysfunction."
Another 2014 study in a medical journal states: "Epidemiological, biological, and clinical links between periodontal and cardiovascular diseases are now well established. Several human studies have detected bacterial DNA corresponding to periodontal pathogens in cardiovascular samples. Intraplaque hemorrhage has been associated with a higher risk of atherosclerotic plaque rupture, potentially mediated by neutrophil activation. In this study, we hypothesized that plaque composition may be related to periodontal pathogens." (Atherosclerosis. Oct. 2014;236(2):448-455. Epub Aug. 11, 2014).
A 2014 study of prediabetes indicates the following: "... prediabetes is associated with associated disorders typically only considered in with established diabetes. These include cardiovascular disease, periodontal disease, cognitive dysfunction, microvascular disease, blood pressure abnormalities, obstructive sleep apnea, low testosterone, metabolic syndrome, various biomarkers, fatty liver disease, and cancer." (Endocrine. Oct. 8, 2014. [Epub ahead of print])
Conspicuously absent from the above-noted studies are the results and conclusions. This is because they are not relevant to the assumptions the authors state regarding a variety of relationships between the mouth, the bugs, and the body, and the assumptions are the thing. The first study above states that periodontal disease can be considered as a cardiovascular disease risk factor. It further provides the mechanism by which this occurs. The second study noted above states that the links between cardiovascular disease and periodontal disease are well established by three different pathways: epidemiologically, biologically, and clinically. The third study above states that diabetes and prediabetes are associated with periodontal disease. The studies cited are published in highly reputable, peer-reviewed medical journals. There are many, many similar studies in dental journals.
Going back 10 years, the verbiage was different. A 2004 study in the medical journal Stroke stated in the abstract: "Chronic infectious diseases may increase the risk of stroke. We investigated whether periodontal disease, including periodontitis and gingivitis, is a risk factor for cerebral ischemia." (Stroke. Feb. 2004;35(2):496-501. Epub Jan. 5, 2004).
Another 2004 study stated: "Infectious diseases have emerged as potential risk factors for cardiovascular disease (CVD). Epidemiological studies support a connection between periodontal disease, a chronic inflammatory disease of the supporting tissues of the teeth, and CVD. (Circulation. Jun. 8, 2004;109(22):2801-2806. Epub May 3, 2004).
These earlier studies present the evidence accurately for the time in which they were published, but by comparing just the abstracts, rather than the results and conclusions, the pace of research can be discerned. The 2014 statement, "periodontal disease can also be considered another cardiovascular risk factor" is far removed from the earlier statement, "Infectious diseases have emerged as potential risk factors for CVD."
It is indeed interesting to take note of the acceptance of the associations between the mouth, the bugs, and the body by the authors of studies in various medical journals. They are stated as givens prior to providing the details of their studies. It reveals the degree of advancement of knowledge in a 10-year span, which may not sound very impressive, but it also reveals the movement toward acceptance of the oral-systemic interconnections by the dental and medical professions - acceptance as facts rather than theories.
We have come a long way in our understanding, and the cumulative weight of the evidence is making an indelible mark on the health-care professions.
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. He lectures on a variety of topics centered on understanding the impact dental professionals have beyond the oral cavity. Contact him at firstname.lastname@example.org.