The doorway to the body – why good dental hygiene is important
Most of us are aware that poor dental hygiene can lead to tooth decay, gum disease and bad breath – but not brushing your teeth could also have consequences for more serious illnesses, as this month’s news items demonstrate.
Oesophageal cancer
Researchers have found that a bacterial species responsible for gum disease, Porphyromonas gingivalis, is present in 61% of patients with oesophageal squamous cell carcinoma (ESCC). The findings, published in Infectious Agents and Cancer, only detected P. gingivalis in 12% of tissues adjacent to the cancerous cells, and it was not detected in normal oesophageal tissue.
The research team measured the expression of lysine-gingipain, an enzyme unique to P. gingivalis, as well as the presence of the bacterial cell DNA within the oesophageal tissues. Both the bacteria-distinguishing enzyme and its DNA were significantly higher in the cancerous tissue of ESCC patients than in surrounding tissue or normal control sites. The researchers also found that the presence of P. gingivalis correlated with other factors, including cancer cell differentiation, metastasis and overall survival rate.
According to researchers, there are two likely explanations: either ESCC cells are a preferred space for P. gingivalis to thrive; or, the infection of P. gingivalis facilitates the development of oesophageal cancer.
Researchers said that if P. gingivalis is proven to cause ESCC, the implications are enormous, because it would suggest that improving oral hygiene might reduce ESCC risk, screening for P. gingivalis in dental plaque might identify susceptible subjects, and using antibiotics or other anti-bacterial strategies might prevent ESCC progression.
Stroke
Researchers have increased their understanding of the association between certain types of stroke and the presence of the oral bacteria Streptococcus mutans.
Researchers at the National Cerebral and Cardiovascular Center in Osaka, Japan, observed stroke patients to gain a better understanding of the relationship between haemorrhagic stroke and oral bacteria. Among the patients who experienced intracerebral haemorrhage (ICH), 26% were found to have a specific bacterium in their saliva, cnm-positive S. mutans. Among patients with other types of stroke, only 6% tested positive for the bacterium.
The researchers also evaluated MRIs of study subjects for the presence of cerebral microbleeds (CMB), small brain haemorrhages that may cause dementia and also often underlie ICH. They found that the number of CMBs was significantly higher in subjects with cnm-positive S. mutans than in those without.
The authors hypothesise that the S. mutans bacteria may bind to blood vessels weakened by age and high blood pressure, causing arterial ruptures in the brain, leading to small or large hemorrhages.
They said that this study shows that oral health is important for brain health, and that people need to take care of their teeth because it is good for their brain and their heart.
The cnm-negative S. mutans bacteria is found in approximately 10% of the general population, and is known to cause tooth decay.
Kidney disease
New findings from the University of Birmingham show that patients with chronic kidney disease and periodontitis (severe gum disease) have a higher mortality rate than those with chronic kidney disease alone.
The research, published in the Journal of Clinical Periodontology, adds to the growing evidence for poor oral health being associated with other chronic diseases.
Data from 13,734 participants in the US-based Third National Health and Nutrition Examination Survey (NHANES III) were analysed to show that individuals with both periodontitis and chronic kidney disease had an all-cause mortality rate of 41% at 10 years, compared to 32% for those with chronic kidney disease alone.
Periodontitis is a chronic non-communicable disease, and in its most severe form is the sixth most prevalent human disease, affecting 11.2% of the world’s population.
Researchers said that it is important to note that oral health isn’t just about teeth. The mouth is the doorway to the body, rather than a separate organ, and is the access point for bacteria to enter the bloodstream via the gums. They said that many people with gum disease are not aware that they have it; they may just have blood in their spit after brushing their teeth, but this unchecked damage then becomes a high-risk area for the rest of the body.
They further said that diagnosis of gum disease might provide an opportunity for the early detection of other problems, and dental professionals could adopt a targeted, risk-based approach to screening for other chronic diseases.
From www.sciencedaily.com