Written by the clinical team at Rite Dentist. Last updated June 2026.
The Oral Microbiome: Your Mouth Has Its Own Ecosystem
The human mouth contains over 700 species of bacteria, making it one of the most diverse microbial environments in the body. Most of these organisms are beneficial or neutral. Some are pathogenic when they proliferate out of balance.
This balance, the oral microbiome, is disrupted by many things that conventional dentistry does routinely: chlorhexidine mouthwashes that kill bacteria indiscriminately, antibiotic prescriptions for every procedure, fluoride applications that alter the oral pH environment, and amalgam mercury that has known antimicrobial effects that reach beyond the targeted bacteria.
When the oral microbiome is disrupted, the downstream effects can be significant. Research published in the journal Cell Host and Microbe found that oral bacteria identified in the mouth also appear in the gut, and that certain oral pathogens, particularly those associated with gum disease, are overrepresented in the gut microbiomes of people with inflammatory bowel disease, colorectal cancer, and other systemic conditions.
The oral cavity is not a closed system. It is the entrance to the gut, and the microbial community it sends downstream every day shapes what happens there.
How Holistic Dentistry Protects the Oral-Gut Axis
Biological dentistry takes a microbiome-protective approach to oral care. This means making different choices than conventional dentistry at several key decision points.
No routine antibiotics before procedures. Pre-procedural antibiotics are prescribed broadly in conventional dentistry, including for healthy patients who do not have a clinical indication. Repeated antibiotic courses deplete the gut microbiome. We prescribe antibiotics only when there is a clear clinical need.
Targeted antimicrobials rather than broad-spectrum. When we need to address infection in the mouth, we use ozone therapy, which eliminates pathogens selectively without the broad microbial disruption that antibiotics cause.
No chlorhexidine as a routine rinse. Chlorhexidine is a broad-spectrum antimicrobial that kills beneficial oral bacteria alongside pathogenic ones. Research from the University of Plymouth found that daily chlorhexidine use significantly increased oral acidity and suppressed beneficial nitrate-reducing bacteria that are important for cardiovascular health. We do not prescribe it as a standard rinse.
Diet and nutrition counseling. The foods that feed the gut microbiome are largely the same foods that support a healthy oral microbiome: fermented foods, fiber-rich vegetables, polyphenols from berries and dark leafy greens, and minimal processed sugar. We talk about this with patients because dental health and gut health are downstream of the same dietary decisions.
Porphyromonas gingivalis, the primary bacterium in periodontal disease, has been found in the gut, liver, and brain tissue of patients with inflammatory conditions. A 2019 study in Science Advances linked P. gingivalis to Alzheimer’s disease pathology, identifying the bacterium in postmortem brain samples. Treating gum disease is not just about the mouth.
Mercury released from amalgam fillings has demonstrable antimicrobial effects in the oral cavity. This disrupts the natural balance of the oral microbiome. Several studies have noted that people with amalgam fillings have different oral bacterial profiles than those without, and that amalgam removal is associated with shifts in the microbial community toward a healthier balance.
Bacterial species in the human oral microbiome, making the mouth one of the most diverse microbial environments in the body (Human Oral Microbiome Database)
Of saliva swallowed daily, carrying billions of oral bacteria into the gut microbiome every 24 hours — the mouth-gut connection is constant and continuous
Higher colorectal cancer risk associated with high levels of Fusobacterium nucleatum — an oral bacterium — found in gut tissue (Cell Host and Microbe, 2022)
Frequently Asked Questions: The Gut-Mouth Connection
How does oral health affect gut health specifically?
Does gum disease affect more than the mouth?
Can improving oral health improve gut health?
Does oil pulling support the oral microbiome?
Should I be taking probiotics for oral and gut health?
What dietary changes most benefit both oral and gut health?
Your Oral Health Is Your Gut Health
A healthy mouth is the foundation of a healthy digestive system. At Rite Dentist in Los Angeles, we treat them as the connected system they are. Book an assessment today.