The tendency to accumulate dental plaque is an inherent trait — that is, some individuals are heavy plaque formers, while others are not. In all cases, proper oral hygiene and regular dental care are essential to reducing plaque accumulation. Teeth that are fractured, have broken or chipped dental restorations, or have large cavities are places where plaque will tend to accumulate. A combination of personal care and professional care is the key to a lifetime of good oral health.
A number of oral and dental diseases and disorders have been associated with diabetes. The most commonly seen oral complication of diabetes is periodontal disease (gum disease). Periodontal disease can be broadly classified as gingivitis or periodontitis. Gingivitis is inflammation of the soft tissues surrounding the teeth. The alveolar bone, to which the teeth are attached, is unaffected by gingivitis.
Periodontitis is a group of disorders in which the inflammation involves both the soft tissues and the alveolar bone. In periodontitis, the alveolar bone is resorbed — that is, it begins to dissolve at the margin where the tooth is embedded in bone. The result is that the cuff of soft tissue deepens, with the formation of what is referred to as a “pocket.” These pockets are difficult to clean, so bacteria can accumulate and proliferate, which elicits an even greater inflammatory response. The inflammatory cells that are part of this response produce biologically active molecules (enzymes and cytokines) that have many effects, including stimulation of the cells that resorb bone (osteoclasts). This leads to irregular bone architecture that further complicates cleaning.
Sometimes a pus-filled swelling of the gum occurs, known as a periodontal abscess. Teeth can become loose and may eventually need to be extracted; one sign of this is that the gum recedes and the teeth appear longer. It is important to emphasize that periodontitis can be prevented or its onset delayed. Once present, periodontitis can generally be treated.
There is very strong evidence that the extent and severity of periodontitis are greater in people with diabetes than in those without diabetes. Periodontal complications of diabetes were first reported more than 150 years ago, including abscess formation and development of intense inflammation where the tooth and soft tissue meet. Some of the most convincing data on the relationship between diabetes and periodontal disease come from the Pima Indians in Arizona. These Native Americans have the highest incidence of Type 2 diabetes in the world, and studies of this group have demonstrated that periodontitis is more common and more severe among people with diabetes. This was found to be true for all age groups.
The relationship between diabetes and periodontal disease appears to be bidirectional — that is, in addition to the increased occurrence of periodontal disease among people with diabetes, there is evidence that untreated periodontal disease in people with diabetes can negatively affect blood glucose control and, ultimately, health outcomes. There are two lines of evidence to support this conclusion. First, a number of studies have examined the effect of treating existing periodontal disease on blood glucose control in people with diabetes, measuring either fasting plasma glucose or glycosylated hemoglobin (HbA1c, a measure of long-term blood glucose control). Conservative periodontal therapy was found to reduce HbA1c by 0.4%, which lasted for three months after therapy. This occurred in the absence of any medical treatment.
Other studies suggest that if periodontal disease is present in people with diabetes, over time, health outcomes are worse. Another study of the Pima Indians revealed that periodontal disease increases the risk of death from heart or kidney disease. The probability of death from these causes was proportional to the severity of periodontal disease. In this same population, the presence of periodontitis was predictive of nephropathy and end-stage renal (kidney) disease, again depending on severity.