A new clinical study from King's College London shows that root canal treatment that successfully treats common tooth apical infections can not only relieve toothache and save teeth, but may also significantly improve blood indicators related to cardiovascular disease and metabolic abnormalities, including inflammation levels, blood sugar and blood lipid profiles. The research team pointed out that this suggests that the connection between oral health and general health is much closer than people thought.
This first clinical study focusing on "systemic metabolic changes after root canal treatment" tracked the changes in blood chemistry in patients with apical periodontitis after root canal treatment. Apical periodontitis is a common dental infection. When bacteria invade the tooth root and surrounding tissues, if it is not effectively controlled for a long time, the bacteria and their products may enter the bloodstream, trigger a systemic inflammatory response, increase the risk of cardiovascular disease, and interfere with the body's ability to regulate blood sugar. Previous studies have mostly stayed at the level of "there is a relationship between oral infections and systemic diseases," but this study directly asked the key question: whether successful root canal treatment can improve cardiovascular and metabolic health to a measurable extent.
The findings showed that patients who underwent successful root canal treatment experienced a "clinically meaningful decrease" in blood sugar control over a two-year follow-up period, meaning their risk of developing diabetes was expected to be reduced. Over a shorter period of time, patients also saw improvements in their blood cholesterol and circulating fatty acid levels, markers closely related to heart health. In addition, a series of biomarkers related to chronic inflammation showed a gradual downward trend, suggesting an overall reduction in the inflammatory burden. The study also found that oral bacteria from infected teeth are associated with measurable changes in systemic metabolic pathways, further supporting evidence that local pulp infections can affect tissues and organs far away from the mouth.
The study included 65 patients from Guy's and St Thomas' NHS Foundation Trust. The research team continued to monitor a variety of molecular indicators in their blood for two years after root canal treatment, analyzing how the body processes key substances such as sugars and lipids, and responds to disease and treatment. Scientists used nuclear magnetic resonance spectroscopy technology to conduct detailed analysis of proteins and metabolites in the body. Research suggests that by monitoring blood sugar, triglycerides and other lipids, and tryptophan and other metabolism-related indicators, it is possible to assess the patient's recovery and future risks after dental treatment.
Dr Sadia Niazi, lead author of the paper and senior clinical lecturer in endodontics at King's College London, said the significance of root canal treatment should not be limited to improving local conditions in the mouth. It "is likely to also help reduce the risk of serious diseases such as diabetes and heart disease." She emphasized that long-term root canal infection will open channels for bacteria to enter the bloodstream, induce an inflammatory response, and increase blood sugar and blood lipid levels, thereby increasing the risk of multiple chronic diseases. Therefore, dental professionals need to pay attention to the potential impact of such "hidden" infections on systemic health and promote early screening, early diagnosis, and early treatment.
Dr. Niazi called for the medical system to transform towards "integrated care", allowing dentists and general practitioners to work together to jointly monitor patient risks through blood markers to better protect overall health. She noted that it's time to "look beyond the teeth themselves" and take a more holistic view of dental treatments and their knock-on effects on overall health. Although the researchers also cautioned that this finding still needs to be further verified in a larger population, this study has opened a new window for understanding "how oral care supports systemic health."
The study, "Successful root canal treatment improves glucose and lipid metabolism: a longitudinal metabolomic study," was published in the Journal of Translational Medicine and was funded by the Royal College of Surgeons and Dental School.