Interdental cleaning linked to better blood sugar control

Dental Tribune International

Fri. 14. November 2025

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FUKUOKA, Japan: World Diabetes Day, held annually on 14 November, highlights the need for greater awareness of the bidirectional relationship between diabetes and oral health. A new clinical study has found that adults with Type 2diabetes who clean between their teeth at least three times a week with floss or interdental brushes spend more time within the target 24-hour blood glucose range and have more stable glucose profiles. Adults with 20 or more natural teeth also showed lower glucose levels throughout the day, underlining the importance of maintaining oral health in diabetes management.

Treating periodontal disease in patients with diabetes has been scientifically shown to lower their levels of glycated haemoglobin, supporting the role of periodontal treatment as a beneficial adjunct to diabetes management. However, most previous research has focused on clinical interventions. According to the researchers, the impact of everyday oral hygiene practices on day-to-day glucose management in Type 2 diabetes has so far been little studied. In this new clinical study, Sunstar Group collaborated with Clinic Masae Minami and the Minami Diabetes Clinical Research Center, both based in Fukuoka, to investigate the association between oral care routines and glucose profiles and to explore whether inflammation could help explain this link.

For the study, 104 adults with Type 2 diabetes wore continuous glucose monitoring sensors for 14 days. Clinical, biochemical and behavioural data—including oral hygiene habits, dental attendance, remaining teeth, diet, daily activities and metabolic markers—was collected through questionnaires, medical records, and blood and urine tests. The study found that adults who practised interdental cleaning at least three times per week had longer periods within the target glucose range and lower 24-hour average glucose levels—as well as lower fasting glucose levels and more stable day-to-day glucose profiles.

Additionally, the researchers reported that individuals with 20 or more natural teeth showed more favourable 24-hour glucose profiles than those with fewer teeth. More frequent dental visits and brushing teeth twice daily were similarly associated with healthier metabolic and inflammatory markers. These associations remained significant after adjusting for age and sex. Notably, the benefits of interdental cleaning were not fully explained by inflammatory markers, suggesting that additional biological or behavioural pathways may contribute to the observed effects.

According to the International Diabetes Federation, one in nine adults globally—590 million people—have diabetes, nearly half of whom are unaware that they have the condition. It projects that, by 2050, one in eight adults worldwide—approximately 853 million people—will have diabetes, reflecting a 46% increase in the total number of cases.

The study, titled “Oral hygiene practices and glucose profiles assessed through continuous glucose monitoring in adults with Type 2 diabetes”, was published online on 28 August 2025 in Diabetes Spectrum, ahead of inclusion in an issue.

Editorial note:

More information about World Diabetes Day can be found here.