New Neurology studies link periodontal health and caries to cerebrovascular risk
Growing evidence suggests that oral health and cerebrovascular health are more closely connected than once thought. Two recent studies led by researchers in the US, both published in Neurology, have added weight to this association by linking periodontal disease and dental caries with markers of small vessel damage in the brain and with a higher risk of ischaemic stroke.
The first study focused on cerebral small vessel disease, which affects the tiny blood vessels in the brain and becomes more common with age. Researchers examined MRI scans from 1,143 adults with an average age of 77 years to look for signs of small vessel injury, including white matter hyperintensities (bright spots on MRI associated with reduced blood flow), cerebral micro‑bleeds and evidence of previous lacunar infarcts. These kinds of changes are known to be associated with an increased risk of stroke, cognitive decline and problems with walking and balance.
When the investigators compared participants with and without periodontal disease, they found a statistically significant difference in white matter hyperintensity volume. On average, those with periodontal disease had a higher burden of these lesions as a percentage of total brain volume. Although the absolute difference was modest, it was considered clinically meaningful. Importantly, the association remained even after adjusting for major vascular risk factors such as age, blood pressure and smoking status. No clear links were found between periodontal disease and cerebral micro‑bleeds or lacunar infarcts once confounding factors had been taken into account.
Senior author Prof. Souvik Sen, chair of the neurology department at the University of South Carolina School of Medicine Columbia, commented in a press release: “If future studies confirm this link, it could offer a new avenue for reducing cerebral small vessel disease by targeting oral inflammation. For now, it underscores how dental care may support long‑term brain health.” The study, titled “Periodontal disease independently associated with white matter hyperintensity volume: A measure of cerebral small vessel disease”, was published online in the December 2025 issue of Neurology.
A second study by the same research group explored whether oral health status was associated with later risk of ischaemic stroke. This analysis included 5,986 adults with an average age of 63 years who had no history of stroke at baseline and were followed for approximately two decades. Participants were categorised according to the presence of periodontal disease, dental caries or both conditions.
Over the follow‑up period, stroke incidence followed an oral health gradient. The lowest rates of ischaemic stroke were seen in participants with healthy mouths, while the highest rates occurred in those with both periodontal disease and caries. After adjusting for traditional vascular risk factors, individuals with both conditions had nearly double the risk of ischaemic stroke compared with those with good oral health. Even participants with periodontal disease alone showed a significantly elevated stroke risk.
“The findings indicate that periodontitis and caries together are independently linked to higher risk of ischemic stroke. For dental professionals, this underscores the systemic relevance of comprehensive preventive care,” Prof. Sen said. This second study, “Combined influence of dental caries and periodontal disease on ischemic stroke risk”, also appeared online in the December 2025 issue of Neurology.
Together, these two studies support the view that inflammation and infection in the mouth may be connected to vascular injury in the brain. They do not prove that periodontal disease or caries directly cause small vessel damage or stroke, but they strengthen the case for a meaningful association even after other risk factors are considered. For clinicians, the findings serve as another reminder that maintaining periodontal health and managing caries may have benefits that extend beyond preserving teeth and gingivae, potentially contributing to better long‑term cerebrovascular health. Further research will be needed to clarify mechanisms and to determine whether improving oral health can reduce the burden of brain vascular disease and stroke in ageing populations.