The importance of good oral hygiene is accepted, not just for the health of your teeth but also your general health. However, several studies suggest there may be a link between periodontal disease and cancer so it may be even more important to attend to your oral health than previously thought.
Periodontitis, or gum disease, is where the tissue surrounding the base of the teeth or gums becomes inflamed. In severe examples of the condition, periodontitis can cause significant deterioration of the gum tissue and even spread to the bone surrounding the teeth.
It is estimated that as many as half of adults in the USA who are over 30 years of age may have some type of periodontitis. As the incidence of periodontal disease increases with age, this figure is thought to increase to as many as seven in ten adults who have periodontal disease and are over 65 years old.
Chronic periodontitis linked to increased risk for oral, lung and pancreatic cancer
To compound the challenge of living with periodontitis, the risk of cancer is thought to increase with chronic periodontitis.
In a large, longitudinal (five years) study found an increased risk for cancer in individuals with chronic periodontitis. This particular study found an association between periodontal disease and several types of cancer including oral cancer, lung cancer and pancreatic cancer. The study proved that individuals with chronic periodontitis were 1.23 more likely to be affected by cancer.
Gum recession and bone loss increase the likelihood of oral and oropharyngeal cancer
Another study examined patients with and without oral cancer and, while no link was found between oral cancer and gum inflammation, they did find that receding gums increased the risk. This particular study proved that patients who suffered from gum recession were close to 2 times more likely to be affected by oral cancer.
Furthermore, a study examining squamous cell carcinoma of the tongue has found an increased association between bone loss and the risk of oral cancer. The likelihood wasn't small at all: the risk for oral cancer was five times higher per millimeter of radiographically-determined bone loss in patients who had increased bone loss compared to those who didn't.
However, thankfully, results from other studies don't show an association between oral and oropharyngeal cancer, even where it was linked to an increased risk for other specific cancers. However, only three of twelve studies reviewed have also found no association whatsoever between periodontal disease and oral or other head and neck cancers.
Human papillomavirus — a significant risk factor for oral and oropharyngeal cancer, but what about periodontal disease?
Human papillomavirus (HPV) is considered a significant risk factor for oral and oropharyngeal cancer, including for those without traditional risk factors. It is thought to be the leading cause of cancers in the back of the throat, back of the tongue and tonsils, for example. The risk is thought to be greater in men than women due to differences in the way men and women contract the virus and how they develop antibodies to it.
The link between gum disease, HPV and cancer may be more complicated as the findings from research on the connections between periodontitis and oral HPV infection is inconsistent. Where periodontitis appears to be associated with increased incidence of HPV, it may be that the inflammation and damaged tissue resulting from the periodontitis simply provides an ideal environment for HPV to lurk and flourish; periodontal pockets are one such example.
A strong link between periodontitis and pancreatic cancer
Pancreatic cancer is an especially unpleasant condition, not least as symptoms are usually slow to develop and often don't become obvious until the disease is too advanced for treatment. Therefore from a public health perspective, finding indicators that might enable detection at earlier, treatable stages would be extremely beneficial.
Research is in early stages but it is thought that gum disease may indeed be a risk factor worth exploring. One study indicated that even after excluding other independent variables (such as age, smoking or other systemic conditions) men with periodontal disease were more than two-thirds more likely to develop pancreatic cancer compared to those without.
It is thought that certain periodontitis-specific bacteria may increase the risk of certain types of cancer and specifically pancreatic cancer; or that an enzyme found both in specific cancerous tumors (Td-CTLP enzyme) and considered instrumental in the development of gum disease may be significant. This enzyme is thought to activate other enzymes that cancer cells use to dominate healthy tissue and, at the same time, it also decreases the effectiveness of the immune system more generally; this all allows cancer cells to dominate healthy cells. Or it may just be that as cancer is often brought on by inflammation, the very state of long-term persistent inflammation characteristic of periodontitis (especially if untreated) is ultimately to blame.