Unavoidable Exposures · Part 3
This series covers the modern toxic background that conventional medicine isn't measuring. Part 1 covered synthetic fragrance. Part 2 covered vaping. This post covers dental procedures and oral health — an exposure most people never think about because it happens in a clinical setting that implies safety.
There is a particular category of toxic exposure that gets very little attention in functional health circles — not because it's rare or minor, but because it happens in a clinical environment and is therefore assumed to be safe by association.
Dental treatment is that exposure.
I am not making the argument that dentistry is inherently dangerous or that people should avoid dental care. The opposite is true — dental disease, untreated, has serious and well-documented systemic health consequences. The tooth-cardiovascular connection alone is sufficient reason to take oral health seriously as a systemic health issue.
What I am making the argument for is awareness — understanding what goes into your body during a dental appointment, which aspects are genuinely concerning and which are overstated, and what a simple clinical protocol can do to support your body before and after procedures that involve significant chemical exposure.
The exposures — what's actually happening
Mercury Amalgam
Dental fillings · Ongoing vapour release
Dental amalgam is approximately 50% mercury by weight — the remainder being silver, tin, copper, and zinc. It has been used in dentistry for over 150 years. The controversy is not about whether amalgam releases mercury — it does, continuously, particularly during chewing, grinding, and temperature changes. The controversy is about whether the dose is clinically significant at the individual level.
The World Health Organisation states that dental amalgam is the largest source of mercury exposure for people in developed countries who have multiple fillings. The vapour released is inorganic mercury, which is absorbed through the lungs and distributed to organs — with particular affinity for the kidneys, liver, and brain. Mercury is a potent neurotoxin and nephrotoxin. It inhibits multiple enzyme systems, depletes glutathione, and interferes with selenium metabolism (selenium binds mercury in a 1:1 ratio, effectively sequestering it — which is why selenium status matters for those with amalgam fillings).
The significant exposure events are amalgam placement and removal — both involve drilling which generates mercury vapour and particles. Removal of amalgam fillings without appropriate protective protocol (rubber dam, high-volume suction, protective supplements) is potentially more hazardous than leaving them in place. This is one of the most important pieces of information anyone with amalgam fillings should have before agreeing to have them removed.
Clinical relevance: highest for people with multiple fillings, kidney dysfunction, high fish consumption (cumulative mercury load), autoimmune conditions (mercury drives immune dysregulation), and neurological symptoms
BPA and Composite Resins
White fillings · Dental sealants · Bonding agents
Composite resins — the tooth-coloured materials used in white fillings and sealants — were introduced largely as a mercury-free alternative to amalgam. The irony is that many contain bisphenol-A (BPA) or BPA-releasing compounds including bis-GMA (bisphenol A glycidyl methacrylate) and bis-DMA (bisphenol A dimethacrylate).
BPA is a well-characterised endocrine disruptor — it binds oestrogen receptors and disrupts hormonal signalling at nanogram concentrations. Studies have detected BPA in saliva for up to 24 hours after composite placement. Dental sealants in children are a particular concern given the oestrogenic effects of BPA on developing endocrine systems.
Not all composites contain BPA — BPA-free formulations exist and a dentist who is asked specifically about BPA content should be able to specify what they're using. The problem is that this question is almost never asked, and the information is almost never volunteered.
Clinical relevance: highest for women with oestrogen-sensitive conditions (endometriosis, fibroids, hormonal cancers), children receiving sealants, and those with MTHFR variants affecting oestrogen detoxification
Local Anaesthetic — Articaine and Epinephrine
Injected during most dental procedures
The most commonly used dental local anaesthetic in the UK is articaine with epinephrine (adrenaline). The epinephrine serves as a vasoconstrictor — it narrows blood vessels at the injection site, reducing bleeding and extending the duration of anaesthesia by slowing the absorption of articaine into systemic circulation.
The systemic epinephrine load from a standard dental injection is small and is generally well tolerated. However, in people with cardiovascular disease, arrhythmias, thyroid conditions (particularly hyperthyroidism), or anxiety disorders, even small doses of systemic epinephrine can trigger palpitations, tachycardia, elevated blood pressure, and anxiety responses. People who notice their heart racing, feel shaky, or feel intensely anxious after dental injections are likely responding to the epinephrine component, not the articaine itself.
Epinephrine-free local anaesthetics are available (mepivacaine, prilocaine) and are appropriate for people with relevant cardiovascular conditions. Asking your dentist specifically for epinephrine-free anaesthetic is a reasonable and achievable request.
Clinical relevance: cardiovascular conditions, arrhythmias, hyperthyroidism, anxiety disorders, adrenal insufficiency, those on monoamine oxidase inhibitors or tricyclic antidepressants
Chlorhexidine Mouthwash
Routinely prescribed post-extraction and for gum disease
Chlorhexidine is a broad-spectrum antiseptic mouthwash routinely prescribed after dental extractions and for the management of periodontal disease. It is effective at reducing oral bacterial load. It is also indiscriminate — it kills beneficial bacteria alongside pathogens, including the nitrate-reducing bacteria in the oral cavity that are essential for nitric oxide production.
This is the most clinically striking dental toxicity story that almost nobody knows. Nitric oxide — produced when oral bacteria convert dietary nitrate (from green leafy vegetables, beetroot) to nitrite, which is then reduced to NO — is a potent vasodilator that regulates blood pressure, endothelial function, and cardiovascular health. The oral nitrate-to-nitrite-to-nitric oxide pathway is a significant contributor to systemic NO bioavailability.
A landmark study published in Free Radical Biology and Medicine (Joshipura et al., 2013) showed that twice-daily chlorhexidine mouthwash use significantly increased systolic blood pressure — by an average of 2–3.5 mmHg — compared to placebo, via depletion of nitrate-reducing oral bacteria. This is a measurable, reproducible cardiovascular effect from a commonly prescribed mouthwash. Another study showed that morning blood pressure was higher on days when participants used chlorhexidine before breakfast compared to days when they ate first — because the dietary nitrate reduction was impaired.
Short-term use for specific indications is clinically appropriate. Routine long-term use — which many patients are effectively encouraged toward — carries genuine cardiovascular cost.
Clinical relevance: anyone with elevated blood pressure, cardiovascular disease risk, or regular mouthwash use. The microbiome-disrupting effect extends beyond blood pressure to systemic immune and inflammatory consequences
Fluoride
Treatment gels · Toothpastes · Water supply in some areas
Fluoride's role in dental health — reducing caries by incorporating into the hydroxyapatite crystal structure of tooth enamel — is well established and represents one of public health's genuine successes. The controversy is not about topical fluoride at appropriate concentrations. It is about systemic fluoride accumulation from multiple simultaneous sources — water, toothpaste, dental treatments, fluoridated salt, some foods — and the evidence for effects on thyroid function and neurological development at higher cumulative exposures.
Fluoride is a competitive inhibitor of iodine uptake in the thyroid — iodine and fluoride both use the sodium-iodide symporter. At sufficient concentrations, fluoride reduces thyroid hormone synthesis. A systematic review of studies from high-fluoride areas found consistent associations with lower IQ in children — the mechanism likely involves fluoride's effects on neurological development and thyroid function. These studies were from areas with naturally high water fluoride concentrations above those used in UK water fluoridation, but they raise legitimate questions about cumulative exposures.
The precautionary principle for thyroid-compromised individuals — particularly those with Hashimoto's or hypothyroidism already on the borderline of adequate function — is to minimise unnecessary systemic fluoride exposure while maintaining appropriate topical dental fluoride use.
Clinical relevance: highest for those with thyroid conditions, iodine insufficiency, and children during neurological development periods
Dental X-Ray Radiation
Diagnostic imaging · Routine check-ups
Modern digital dental X-rays deliver a fraction of the radiation dose of older film X-rays — a bitewing X-ray delivers approximately 5 microsieverts, comparable to a few hours of background radiation. For most people, this represents a negligible risk. The concern arises with frequency — annual full-mouth X-ray series for patients who may not clinically require them, and the cumulative effect across a lifetime of dental care.
The thyroid gland sits directly in the field of panoramic dental X-rays. Lead thyroid collars should be standard practice during dental X-rays — they are not always offered or used. For patients with thyroid conditions, requesting a thyroid collar explicitly is a reasonable precaution. The clinical question of whether X-ray frequency matches clinical need is a legitimate conversation to have with your dentist.
Clinical relevance: thyroid conditions, pregnancy, children, those receiving frequent X-rays for ongoing dental work
The tooth-heart connection — what the evidence actually shows
The relationship between oral health and cardiovascular disease is one of the most well-documented but least-discussed connections in medicine.
Oral Health and Cardiovascular Disease — The Evidence
Porphyromonas gingivalis — the primary pathogen in periodontal disease — has been detected in atherosclerotic plaques. It produces enzymes that degrade vessel wall components and drives local inflammation.
Streptococcus mutans — the primary caries-causing bacterium — can enter the bloodstream during dental procedures and colonise damaged heart valves. Infective endocarditis is a serious and potentially fatal consequence.
People with periodontal disease have significantly higher rates of cardiovascular disease, stroke, and diabetes — independent of shared risk factors like smoking. Meta-analyses show 19–34% increased cardiovascular risk in people with significant gum disease.
The mechanism is dual — direct bacterial translocation into circulation AND chronic systemic inflammation from periodontal disease driving CRP elevation, endothelial dysfunction, and accelerated atherosclerosis.
The chlorhexidine-blood pressure connection (described above) represents a third pathway — oral microbiome disruption impairs the nitrate-nitric oxide pathway that regulates vascular tone.
People with missing teeth — a surrogate marker for historical dental disease — have higher all-cause mortality. This is not fully explained by shared lifestyle factors.
The clinical implication is that oral health is not a separate department from systemic health. It is part of the same system — and the microorganisms, inflammatory signals, and chemicals that enter circulation at the gum-tooth interface affect the whole body in ways that dentistry as a discipline has been slow to communicate and medicine has been slow to integrate.
The oral microbiome — more important than you think
The mouth contains approximately 700 bacterial species in a biofilm ecosystem that has evolved alongside the human body for millions of years. This ecosystem performs functions that are only now being properly mapped — nitric oxide production, immune modulation, digestion of dietary nitrates, and protection against pathogenic organisms.
The oral microbiome is the gateway to the gut microbiome — the bacteria you swallow continuously from your oral cavity seed and influence the gut microbial community. Oral dysbiosis — a pathogenic shift in oral microbial populations — is associated with dysbiotic changes in the gut. The oral-gut microbiome connection is real and runs in both directions.
Chlorhexidine, antibiotics prescribed for dental infections, and repeated dental antiseptic treatments all disrupt the oral microbiome. The consequences extend beyond the mouth — into gut health, cardiovascular function, and systemic immune regulation.
Oral probiotics — particularly Lactobacillus reuteri, Lactobacillus salivarius, and Streptococcus salivarius K12 — have emerging evidence for supporting oral microbiome health, reducing periodontal pathogen burden, and reducing gum inflammation. They represent a restorative intervention after any antimicrobial dental treatment.
The pre and post dental protocol
This is what I'd recommend as a clinical protocol around significant dental procedures — amalgam placement or removal, extractions, periodontal treatment, or any procedure involving drilling of existing fillings.
Clinical Pre and Post Dental Protocol
48–72 hours before the appointment
→Chlorella 3–4g daily — a green algae with documented mercury-binding capacity in the gut. Start before the appointment so it's present in the digestive tract during and after the procedure. Take away from meals to maximise binding capacity.
→Vitamin C 2–3g daily — supports glutathione synthesis, reduces oxidative stress from mercury exposure, and supports immune function. Divide across the day rather than taking as a single dose.
→NAC (N-Acetylcysteine) 600mg twice daily — the most bioavailable glutathione precursor. Glutathione is the body's primary mercury conjugation molecule in phase II detoxification. Ensures maximum detoxification capacity at the time of exposure.
→Selenium 200µg — binds mercury in a 1:1 ratio, forming a stable, non-toxic complex. Selenium status is particularly important for those with existing amalgam fillings and is often insufficient in the UK population.
→Magnesium glycinate 300mg at night — supports detoxification enzyme activity and reduces the physiological stress response to anaesthetic and epinephrine.
Day of the appointment
→Chlorella 3g with water 30–60 minutes before the appointment — present in the gut during the procedure to bind any swallowed mercury particles.
→Vitamin C 1–2g before — antioxidant support during the acute exposure period.
→If receiving amalgam removal: ask your dentist about rubber dam use, high-volume suction, and whether they follow SMART protocol (Safe Mercury Amalgam Removal Technique). These significantly reduce mercury vapour inhalation during removal.
→If concerned about BPA: ask specifically whether the composite being used is BPA-free. This is a legitimate question and some practices use BPA-free materials as standard.
→If you have cardiovascular concerns or anxiety: ask for epinephrine-free local anaesthetic (mepivacaine or prilocaine). Not all practices stock these — worth asking in advance.
24–72 hours after the appointment
→Continue chlorella 3–4g daily for 3–5 days post-procedure — ongoing gut-binding support as mercury is mobilised and excreted.
→Modified citrus pectin (MCP) 5g twice daily — a pectin-derived compound with evidence for binding heavy metals in the gut and supporting their urinary excretion. Complementary to chlorella rather than a replacement.
→Continue NAC and vitamin C for 5–7 days — maintain glutathione synthesis during the period of ongoing mercury clearance.
→Avoid chlorhexidine mouthwash unless specifically indicated for an acute infection. If prescribed, use for the minimum necessary duration. Saltwater rinses are an effective alternative for wound healing after extractions.
→Oral probiotics — Lactobacillus reuteri or Streptococcus salivarius K12 lozenges or chewable tablets for 2–4 weeks post-procedure to restore oral microbiome balance, particularly after chlorhexidine use or antibiotic prescription.
→High-nitrate foods — rocket, spinach, beetroot — to restore the nitrate-nitric oxide pathway if chlorhexidine has been used. These foods provide the substrate for the nitrate-reducing bacteria as they re-establish. Eat them before using any antiseptic mouthwash if you must use one.
For routine check-ups and scale and polish (lower risk)
→Vitamin C 1–2g day before and day of — general antioxidant support.
→Oral probiotics for 1–2 weeks after if any antiseptic has been used.
→The full protocol above is primarily for procedures involving amalgam, drilling, or significant periodontal treatment.
The underlying oral health foundation
The most effective pre-dental protocol is the one that reduces the need for significant dental intervention in the first place. Oral health is substantially nutritionally determined — and the nutritional factors that drive dental disease are the same ones that drive systemic disease.
Vitamin K2 is essential for the proper mineralisation of tooth enamel — via the same osteocalcin-activation mechanism relevant to bone health. Weston A Price's observation, documented in the 1930s, that traditional populations eating nutrient-dense traditional diets had remarkably low rates of dental caries while industrially-fed populations showed dramatic increases — is supported by the modern understanding of fat-soluble vitamin K2's role in dental mineralisation.
Vitamin D supports tooth mineralisation and the immune defence of the oral mucosa. Low vitamin D is associated with higher rates of periodontal disease and caries.
Magnesium is incorporated into tooth enamel alongside calcium. Low magnesium produces structurally inferior enamel that is more susceptible to decay.
Sugar and refined carbohydrates feed Streptococcus mutans — the acid-producing caries bacterium. The frequency of sugar exposure matters as much as the quantity — continuous snacking on sugary foods maintains the acidic oral environment that drives enamel erosion, while eating sweets as part of a meal followed by saliva flow is significantly less damaging.
Xylitol is worth a specific mention — it actively inhibits Streptococcus mutans growth (the bacterium cannot metabolise it and it competitively occupies the receptor sites the bacterium uses for adhesion). Xylitol chewing gum after meals has genuine clinical evidence for caries reduction and is one of the few genuinely evidence-based dental interventions that doesn't involve a pharmaceutical or a drill.
The mouth is not a separate organ that the dentist manages twice a year. It is the beginning of the digestive tract, the first point of immune contact with the external environment, and a continuous source of bacterial and inflammatory signals that enter systemic circulation. Oral health is systemic health — the research has been saying this for decades. The clinical silos haven't caught up.
A note on amalgam removal decisions
The question of whether to remove existing amalgam fillings is one I am asked regularly, and I want to answer it carefully.
Amalgam in stable, intact fillings releases mercury at a low, continuous rate. Drilling it out releases a significant pulse of mercury vapour and particles — far exceeding the chronic low-level release of the intact filling. Removing amalgam fillings without appropriate precautions (SMART protocol, rubber dam, high-volume evacuation, pre and post protective supplements) can produce a worse acute exposure than leaving the fillings in place.
The clinical indications for amalgam removal are: fillings that are fractured, corroded, or leaking (where mercury release is already elevated); preparation for pregnancy (mercury crosses the placental barrier); people with documented mercury sensitivity or relevant autoimmune conditions; people with high total mercury burden confirmed on testing.
For people without these specific indications, the decision to remove intact amalgam fillings is not straightforward and should not be made on aesthetic grounds alone without understanding the procedural exposure risk. If you decide to remove them, do it with a dentist trained in SMART protocol, support your detoxification pathways properly before and after, and don't rush the process — one or two fillings per session with adequate recovery between.
Testing for mercury burden
Where there is clinical suspicion of significant mercury accumulation — neurological symptoms, kidney dysfunction, fatigue, or immune dysregulation in someone with multiple amalgam fillings — the most reliable testing is a provoked urine test using a chelating agent (DMPS or DMSA), which mobilises stored mercury and measures urinary excretion. Standard blood mercury measures only recent exposure, not body burden. This is specialist territory — discuss with a practitioner familiar with heavy metal assessment before proceeding.
Monitoring the Nitrate-Nitric Oxide Pathway
Calroy's 2-in-1 Nitric Oxide Test Strips offer a practical way to track the oral microbiome's nitrate-reducing function — the exact pathway that chlorhexidine disrupts. The dual-pad design measures both salivary nitrate (dietary substrate — are you eating enough leafy greens and beetroot?) and salivary nitrite (bacterial conversion — are your oral bacteria actually doing the work?). This distinction matters clinically: low nitrate suggests a dietary problem; adequate nitrate with low nitrite suggests depleted nitrate-reducing bacteria — the direct consequence of chlorhexidine, antibiotics, or poor oral microbiome health.
Used before and after a course of chlorhexidine, these strips make the microbiome disruption visible and measurable. Used before and after dietary changes or NO-supporting supplementation (L-citrulline, beetroot extract), they confirm whether the intervention is working in your specific biochemistry. Test in the morning before eating for the most consistent baseline. Serial measurements across 4–6 weeks are more meaningful than a single reading. Available from Calroy Health and select functional health suppliers.
Questions about dental exposures and your health?
The DH Clinical Concierge can help you understand the clinical picture behind dental toxicity and whether a pre or post dental protocol is relevant for your situation.
Talk to the Concierge
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