Module 1 Overview

This module introduces the oral microbiome, the body's second-largest microbial community, crucial for both oral and overall health. For dental professionals, understanding this complex system is essential for accurate diagnosis and tailored patient care.

The oral microbiome consists of bacteria (the largest group), archaea, fungi, viruses, and protozoa. Bacteria are not simply "good" or "bad"; their behaviour shifts depending on the environment, leading to dysbiosis (imbalance). This shift can be caused by changes in pH, diet, oxygen levels, immune response, or the presence of specific pathogens.

There are seven main bacterial phyla: Actinomycetota, Bacteroidota, Bacillota, Fusobacteriota, Pseudomonadota, Saccharibacteria, and Spirochaetota. The module also explains the distinct roles of fungi (e.g., Candida), archaea (e.g., Methanobrevibacter oralis), viruses, and protozoa.

Finally, the module identifies five key clinical signs of microbiome imbalance and what each may indicate:

1. Persistent bad breath (Halitosis)
2. Bleeding or inflamed gums
3. Frequent cavities despite good hygiene
4. White or coated tongue
5. Systemic inflammation and related conditions