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Updated: May 3, 2026

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children

Published on: December 31, 2017

Oral microbiota and systemic disease.

Purnima S Kumar¹

¹Division of Periodontology, College of Dentistry, The Ohio State University, 4111 Postle Hall, 305 W. 12th Avenue, Columbus, OH 43210, USA.

|October 17, 2013

Summary

Bacteria cause infections and may indirectly lead to diseases like cancer. This review explores the focal infection theory, examining its history, decline, and resurgence in understanding oral bacteria

Keywords:

Focal infection Focal sepsis Oral bacteria Periodontal medicine Systemic disease

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Area of Science:

Microbiology
Immunology
Oral Health

Background:

Bacteria are primary causes of infectious diseases.
Emerging evidence links bacteria to non-infectious diseases like cancer and rheumatoid arthritis.
The oral cavity harbors bacteria implicated in periodontitis and caries.

Observation:

The oral cavity has long been considered a potential source of distant infections.
The focal infection theory posits that localized infections can cause systemic disease.
This theory has a complex history of acceptance and rejection.

Findings:

The review examines the historical development of the focal infection theory.
It analyzes the reasons for the theory's decline in scientific acceptance.
The paper discusses the re-emergence and current status of the focal infection concept.

Implications:

Understanding the oral microbiome's role in systemic health is crucial.
Revisiting the focal infection theory may offer new insights into disease pathogenesis.
Further research is needed to elucidate the mechanisms linking oral bacteria to systemic conditions.