Cardiovascular diseases and apical periodontitis: association not always implies causality

Area of Science:

• Endodontology
• Cardiology
• Epidemiology

Background:

• Studies suggest a link between apical periodontitis (AP) or root canal treatment (RCT) and cardiovascular diseases (CVDs).
• Association does not imply causation; non-causal relationships are possible.
• Hill's causality criteria are crucial for evaluating potential cause-effect links.

Purpose of the Study:

• To review and analyze the current knowledge on the association between AP and CVDs.
• To assess the evidence for a causal relationship using Hill's criteria.

Main Methods:

• A narrative review of epidemiological studies published in English up to December 8, 2019.
• Analysis of 44 selected articles investigating the association between CVDs and AP or RCT.

Main Results:

• Many cross-sectional studies report a significant association between CVDs and AP (OR 1.6-5.4).
• Other studies found no significant association between AP and CVDs.
• Findings on RCT are contradictory, with some showing correlation, others no association, and some suggesting a protective effect against CVDs.

Conclusions:

• The evidence is inconsistent, preventing the establishment of a causal link between CVDs and endodontic disease.
• Common risk factors may confound the observed associations.
• Longitudinal studies are needed to determine causality by establishing temporal relationships and dose-response gradients.