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Oral bacteria reference

Each genus card links to its writeup. Species writeups are nested under their parent genus.

Actinomyces

An early biofilm colonizer that builds the foundation for the rest of the oral community

A core oral bacterial genus that's one of the first to colonize a clean tooth surface and serves as the scaffold for the rest of the oral biofilm. *Actinomyces* is universally present in healthy mouths but the genus contains both protective species (*A. naeslundii*, *A. oris*) and species that contribute to root caries (*A. viscosus*, *A. israelii*). Your panel reports the species individually — the genus story depends on which species are present.

Cardiobacterium

A common oral commensal that's rarely a concern

Cardiobacterium is a small genus of gram-negative bacteria carried in the mouths of roughly two-thirds of healthy adults. Despite its alarming-sounding name, it's a normal oral commensal in nearly all contexts. The only clinical scenario where it matters is a rare type of heart valve infection in people with pre-existing valve damage.

Species

Cardiobacterium hominis

Corynebacterium

The structural pillar of healthy dental plaque

A health-associated bacterial genus that serves as the **structural scaffold** of healthy dental plaque. *Corynebacterium* filaments form the central pillar around which the rest of the supragingival biofilm organizes. It's depleted in smokers and elevated in cavity-free children. Salivary 16S underestimates its true importance — *Corynebacterium* lives mostly in plaque, not saliva.

Species

Corynebacterium matruchotii

Granulicatella

A core oral commensal found at essentially every site in the mouth

A core oral bacterial genus found at essentially every site in the mouth — saliva, plaque, tongue, cheeks, palate. *Granulicatella* is part of the health-associated community and depleted in aggressive periodontitis. It can occasionally cause heart-valve infections in people with pre-existing valvular disease, but in healthy adults it's a ubiquitous commensal.

Haemophilus

A health-associated genus and one of the bacteria that makes your mouth distinctively yours

A health-associated bacterial genus that lives alongside *Streptococcus* in healthy mouths and contributes to nitrate reduction. *Haemophilus* is among the strongest individual signatures distinguishing one person's oral microbiome from another, and is consistently depleted in smokers.

Species

Haemophilus parainfluenzae

Lautropia

A low-abundance health-associated commensal that travels with the broader aerobic community

A low-abundance oral bacterial genus that's part of the aerobic, health-associated community alongside *Neisseria*, *Haemophilus*, and *Rothia*. *Lautropia* is consistently depleted in smokers — one of the most reproducible findings in the smoking microbiome literature — and recovers with cessation.

Neisseria

A nitrate-reducing health-associated genus with the strongest dietary-nitrate response

A health-associated genus and the strongest dietary-nitrate responder in your mouth. *Neisseria* is consistently depleted in smokers and recovers with cessation.

Porphyromonas

A genus that contains both gum-disease pathogens and health-associated commensals

A bacterial genus that contains both health-associated commensal species (*P. catoniae*, *P. pasteri*) and the most studied gum disease pathogen (*P. gingivalis*). Your panel reports the species individually — check whether you see *P. gingivalis* by name vs. unmatched placeholder sequences ("*Porphyromonas* sp" with a number).

Species

Porphyromonas gingivalis Porphyromonas pasteri

Rothia

A nitrate-reducing health-associated genus

A health-associated genus and one of the most active bacteria at converting dietary nitrate into nitric oxide — the molecule your blood vessels use to stay relaxed. Higher levels track with healthier blood pressure markers in published research.

Species

Rothia mucilaginosa

Streptococcus

A diverse genus spanning protective and cavity-causing species

The most abundant bacterial genus in your mouth — about 1 in 3 of your oral bacteria. *Streptococcus* contains both protective species (*S. salivarius*, *S. sanguinis*) and the cavity-causing *S. mutans*. Your panel breaks this down by species, so the species-level rows in your report tell the real story.

Species

Streptococcus mutans Streptococcus salivarius Streptococcus sanguinis

Veillonella

A complicated genus that does not fit cleanly into "good" or "bad"

Veillonella is a common oral bacterial genus with a complicated story. It can't digest sugar — it eats lactic acid produced by other bacteria. Older textbooks called this protective, but current evidence shows the dominant species (V. parvula) actively amplifies the cavity-causing virulence of S. mutans, and the genus diverts nitrite away from the nitric oxide pathway rather than feeding it. Predominantly negative, especially when paired with elevated S. mutans.

Species

Veillonella atypica Veillonella parvula