A large Swedish study of nearly 5.9 million adults found that gum disease and tooth loss are associated with an elevated risk of primary liver cancer, with gum disease linked to a 25% higher risk and a clear dose-response relationship between fewer remaining teeth and cancer risk.
- Gum disease risk: Patients with periodontitis have a 25% higher risk of liver cancer compared to those with healthy gums.
- Tooth loss impact: Individuals with fewer remaining teeth showed hazard ratios ranging from 1.15 to 1.84 for liver cancer risk.
- Study scope: An analysis of 5.9 million Swedish adults identified 2,374 liver cancer cases over a six-year follow-up period.
- Cancer types affected: Periodontitis was associated with hepatocellular carcinoma, while caries linked to non-hepatocellular carcinoma.
- Research significance: It is the largest population-based study to date investigating the dental disease-liver cancer connection using sibling-comparison analysis.
Dental diseases, including periodontitis, and tooth loss may be linked to a heightened risk of primary liver cancer, according to a large study published on October 25 in the Journal of Clinical Periodontology.
Furthermore, this link appeared to have clear patterns of association for hepatocellular carcinoma and non-hepatocellular carcinoma primary liver cancer, the authors wrote.
“To our knowledge, this is the largest population-based retrospective cohort study to date and the first to apply a sibling-comparison design to investigate the relationship between dental disease, tooth loss and PLC (primary liver cancer) risk, providing strong epidemiological evidence for the association between dental health conditions and PLC risk,” wrote the study's lead author, Dr. Weimin Ye of the department of medical epidemiology and biostatistics at the Karolinska Institute in Stockholm.
Poor oral health has been shown to raise the risk of several types of cancer.
A study published in July 2025 in BMC Oral Health revealed that patients with gum disease may have a 25% higher risk of having gastric cancer in the stomach lining. Also in 2025, a study in BMC Oral Health revealed that periodontitis may be linked to a higher risk of pancreatic cancer.
Despite these associations, there is little evidence showing a link between dental diseases and the risk of primary liver cancer.
To investigate the correlation between dental diseases, tooth loss, and the risk of PLC, a population-based retrospective cohort study that included nearly 5.9 million adults registered in the Swedish Dental Health Register between 2009 and 2016 was conducted.
Cox regression analyses were used to study the correlation between dental diseases, tooth loss, and the risk of liver cancer, using attained age as the timescale and adjusting for possible confounders. Furthermore, a sibling comparison analysis was used to control for shared genetic and early-life environmental factors.
During a mean follow-up of about six years, 2,374 liver cancer cases were identified via the cancer register. Of those, 1,856 were hepatocellular carcinoma and 518 were non-hepatocellular carcinoma PLC cases, the authors wrote.
Caries (hazard ratio [HR] = 1.15, 95% CI: 1.02 to 1.30) and gum disease (HR = 1.25, 95% CI: 1.12 to 1.39) were linked to an elevated risk of liver cancer. Additionally, there was a clear dose-response relationship between fewer remaining teeth and cancer risk, with HRs ranging from 1.15 to 1.84 (p < 0.001) for individuals with fewer teeth compared with those with greater than 27 remaining teeth, they wrote.
Also, caries was linked to non-hepatocellular carcinoma, whereas periodontitis was associated with hepatocellular carcinoma. Finally, edentulism was more strongly correlated with non-hepatocellular carcinoma than with hepatocellular carcinoma, the authors wrote.
The study was not without limitations. Since the Dental Health Register was established in 2008, dental diseases or treatments that occurred prior may not have been included. This may have resulted in some exposure misclassification, they wrote.
“This large population-based cohort study, combined with the first sibling-matched analysis, provides evidence that poor dental health, including caries, periodontitis and tooth loss, is associated with an elevated risk of PLC,” Ye and colleagues wrote.
