Dental Plaque and Cancer Mortality – Is There a Link?

Dental plaque may be associated with premature death due to cancer, according to a study¹ of randomly selected adults in Sweden. The study authors suggest that there may be a link between plaque levels and cancer and death due to cancer. The cause and development of cancer is not studied; however, the presence of high bacterial load on tooth surfaces and in gingival accumulations was associated with poor outcomes.

“Although population studies of this kind are difficult to conduct, they can have potentially important implications,” says Dr. Joel Epstein, a JCDA editorial consultant and director of oral medicine in the division of otolaryngology and head and neck surgery at the City of Hope, a comprehensive cancer centre in Duarte, California. “In cancer patients, oral health has been identified as a concern during and following cancer therapy. Although the study’s conclusions do not demonstrate cause and effect, they raise questions about potential systemic consequences of poor oral health and specifically death due to cancer.”

Researchers followed 1390 periodontally healthy Swedish men and women over 24 years and found that subjects who died within the study period had a statistically significant relationship to death due to cancer and plaque levels when other factors were controlled for in the analysis. Dental status was established using a clinical oral examination that recorded oral health parameters for all subjects: number of remaining teeth excluding third molars, gingival inflammation and oral hygiene status using the plaque index and calculus index.

According to national statistics in Sweden, 58 subjects died within the study period, 35 of which were due to cancer. Researchers considered all deaths occurring within the study period as “premature,” since the deceased women and men were expected to live longer according to population demographics in Sweden.

Subjects also completed a questionnaire that collected information related to demographics and clinical oral health, such as dental visits and smoking. Overall, premature death was more likely to be associated with high amounts of dental plaque, increasing age and male gender.

This study did not assess the prevalence of cancer and oral risk factors.

Dr. Epstein suggested that the association between cancer mortality and dental plaque highlights the need for more studies to better understand the role of bacterial plaque in carcinogenesis and death due to cancer. This study extends the discussion about oral health, specifically plaque levels, and its importance in oncology, to include possible carcinogenesis and death due to cancer. It also extends the known impact of oral health and plaque levels on oral complications of cancer therapy to include the possibility of premature death due to cancer.