Table 2.

Summary of obstacles to determining the microbial etiology of caries

Obstacle or Confounder
Sampling Choices
- saliva instead of dental plaque  - plaque pooled from sites of caries and intact enamel  - microbiology of carious sites can vary considerably over small distances
Substrate Susceptibility
- tooth sites may vary in susceptibility to dental plaque of similar composition
Caries Process
- the microbiology of caries evolves as the lesion progresses in severity
Genetic Contributions
- salivary composition and constituents may elevate or depress caries risk
Determination of the Plaque Microbiome
- culture-based methods have a narrow focus  - next generation sequencing outcomes may differ from lab to lab analyzing the same sample  - 16S gene-based sequencing poorly differentiates species of oral streptococci
Biological Significance
- little evidence for what constitutes biologically significant levels of individual plaque species
Caries Incidence
- the microbial basis for occasional caries may typically differ from that for rampant caries