Biological dentistry covers treatments with varying levels of evidence behind them. Metal-free fillings are ordinary restorative dentistry. Ceramic implants have clinical guideline recognition. Cavitation surgery has no professional body endorsement, though the research on the underlying condition has moved recently. The table below sets each treatment against its conventional equivalent.

Treatment comparison

Treatment	Conventional equivalent	What the evidence shows	Mainstream position
Metal-free fillings and crowns	Amalgam fillings	Composite and ceramic are established restorative materials. Amalgam is being phased out on environmental grounds, not toxicological ones.	Uncontested. In the UK, amalgam has been restricted since 1 July 2018 for children under 15, pregnant and breastfeeding women and primary teeth — on environmental, not clinical-safety grounds — with a UK-wide phase-out deadline of 31 December 2034 set at Minamata COP-6. The EU banned it outright from January 2025.
Ceramic (zirconia) implants	Titanium implants	Five-year survival of 97.2%, comparable to titanium. Evidence applies mainly to one-piece designs; two-piece systems have limited long-term data. No evidence zirconia outperforms titanium on peri-implantitis.	Guideline-recognised. Germany has had an S3 guideline since October 2022, framed on material behaviour rather than systemic health.
Protected amalgam removal	Standard removal	Drilling out an old filling volatilises mercury vapour, frequently above safety thresholds for more than an hour afterwards. The bundled IAOMT protocol itself has never been evaluated by any professional body.	Split. Protection during necessary removal is well founded. Elective removal of intact fillings to treat illness is advised against.
Extraction plus immediate ceramic implant	Root canal treatment	No evidence links successfully root-treated teeth to systemic disease. Research interest is in untreated apical infection — the disease, not the treatment.	Against. The AAE finds no valid scientific evidence for the systemic claim.
Cavitation surgery	No equivalent; conventionally not treated	A 2022 systematic review of 29 studies reported pain remission of 66–100% after surgical curettage, with up to a third showing minimal improvement or recurrence, and found no gold-standard diagnostic method. A 2025 molecular study found affected bone has a different gene expression profile from healthy controls, on a sample of three against three. A separate 2025 radiological study of 36 patients (Ghanaati et al., Bioengineering 12(2):128) found that after flapless upper-premolar extraction, cavities formed in most sockets and persisted at six months — but described the process as physiological rather than pathological, and framed its recommendation around implant planning rather than treatment.	Not endorsed. The AAE will not condone it, US insurers classify it as experimental, and no UK dental body has published a position on it at all.
Platelet-rich fibrin (PRF)	Unassisted healing	A randomised split-mouth trial in November 2025 found PRF alone did not prevent socket residue, and recommended combining it with bone substitute material.	Accepted as an adjunct. The specific claim that it removes the need for grafting material is not supported.
Titanium sensitivity testing	Standard patch testing	No validated test exists. Results are wildly discordant — one study found 37.5% positive on one method and 0% on another in the same patients.	Not established. The mechanism appears innate rather than allergic, which undercuts both the dismissal and the commercial testing model.

What you can get on the NHS

NHS dental treatment in England is charged in three bands: £27.90 for examination and advice, £76.60 for fillings and root canal treatment, £332.10 for crowns and dentures. Where each of the treatments above sits against that structure decides more about what patients actually do than the evidence does.

Metal-free fillings and crowns. The only item on this list routinely available. White fillings are provided on the NHS “when clinically necessary” — in practice usually front teeth, with amalgam still recommended for back ones. Crowns fall under Band 3. Amalgam itself has been restricted across the UK since 1 July 2018 for children under 15, pregnant and breastfeeding women and primary teeth, on environmental rather than clinical-safety grounds, with a UK-wide phase-out deadline of 31 December 2034 agreed at Minamata COP-6.

Protected amalgam removal. Partly. Replacing a filling is Band 2 treatment. The protective protocol around it — rubber dam, high-volume evacuation, external air filtration — is not itself an NHS service.

Extraction plus immediate ceramic implant. Partly. Extraction and root canal treatment are both Band 2. The implant is private.

Ceramic implants, cavitation surgery, platelet-rich fibrin and titanium sensitivity testing. None appears among the treatments listed in any NHS band.

The split is worth focusing on, because no clinic page will. Of those four private-only treatments, one is private for ordinary reasons of NHS scope: ceramic implants have clinical guideline recognition and cost is the barrier, not evidence. The other three are the three weakest-evidenced items in the table above. In practice, the further a treatment sits from the evidence, the more likely a patient is paying for it directly and the less likely anyone independent has assessed whether it worked. That doesn’t automatically mean it doesn’t work. It is just that robust research may not have been done.

Materials: fillings, crowns and implants

The argument here is materials science rather than contested physiology. The EU banned dental amalgam from January 2025 and a global phase-out is agreed for 2034, so metal-free restoration is simply where dentistry is going. On implants, the International Team for Implantology’s 2023 consensus puts zirconia five-year survival at 97.2%, and Germany has had an S3 guideline covering ceramic implants since October 2022.

The guideline sets two limits. The evidence applies mainly to one-piece designs, with two-piece systems recommended only under study conditions. And there is no clinical evidence that zirconia outperforms titanium at preventing peri-implantitis.

Amalgam removal

Amalgam removal divides cleanly into two questions that are often run together. Removing a filling that needs replacing anyway, with protection, is well founded: high-speed drilling volatilises mercury vapour frequently above safety thresholds for more than an hour afterwards, according to a mainstream occupational health journal. Removing intact, sound fillings to treat illness elsewhere is a different proposition. The FDA advises against it and the ADA’s Code of Ethics calls it improper and unethical in non-allergic patients where the dentist alone has recommended it.

On the named removal protocol: it has never been evaluated by the ADA, the FDA or any UK body, positively or negatively. Its individual components — rubber dam, high-volume evacuation, sectioning rather than drilling out, external suction — are standard uncontroversial practice.

Cavitation surgery and root canal replacement

Cavitation surgery is the treatment on which biological dentistry and conventional dentistry are furthest apart. The American Association of Endodontists will not condone surgical intervention for suspected lesions of this type, and Aetna classifies the procedure along with its bone grafting and detection imaging as experimental, investigational or unproven.

The research has moved in the past two years, and mostly through one collaboration between Professor Shahram Ghanaati at Goethe University Frankfurt and Johann Lechner, the Munich clinician who has documented the condition for four decades. A molecular study published in May 2025 compared affected jawbone against healthy controls and found a different gene expression profile, with CCL5/RANTES, VEGF and IGF upregulated and collagen types I, II and IV downregulated. The sample was three cases against three controls, age and sex were not accounted for, and the authors call for replication. Separately, a 2025 scoping review from a conventional academic group in Poland treats the condition as a real entity characterised by silent inflammation and recommends advanced imaging together with surgical intervention.

The largest systematic review to date screened 4,051 articles and included 29. Pain remission after surgical curettage ranged from 66% to 100%, with up to a third of patients showing minimal improvement or recurrence. No gold-standard diagnostic method could be identified, every included study was observational with a high risk of bias, and the authors called for prospective trials.

Replacing a root-treated tooth with an implant on systemic grounds is a separate question. The AAE finds no valid scientific evidence linking root canal treatment to systemic disease, and where research interest has revived it concerns untreated apical infection — the disease rather than the treatment.

The tension in this literature is worth exploring, because it is usually reported one way or the other. The research most often cited in support of cavitation surgery is Ghanaati’s, and Ghanaati’s group is not arguing that the finding is a disease. Its 2025 radiological study concluded that cavitation formation “seems to be a physiological process that takes place in most cases and persists even after six months,” and its practical recommendation was that implant planning requires three-dimensional imaging. If incomplete socket healing is near-universal, that is the strongest available argument against treating it as pathology — and it is the same argument, from the same authors, that the treatment’s advocates cite as vindication.

The adjuncts

Platelet-rich fibrin, drawn from the patient’s own blood, is accepted as a healing adjunct. A randomised split-mouth trial published in November 2025 found that PRF alone did not prevent socket residue after third molar extraction, and recommended combining it with bone substitute material — the opposite of the position that adequate systemic preparation removes the need for grafting.

On titanium sensitivity testing, a 2022 review of the available diagnostics concluded that no validated test exists. Results are discordant, with one study finding 37.5% of patients positive on one method and none of the same patients positive on another, and the authors argue the mechanism is innate rather than allergic. That cuts against the position that titanium sensitivity is not a real phenomenon, and against the reliability of any test currently sold for it.

Cone beam imaging

Every treatment in the table above is downstream of a diagnosis, and in biological dentistry the diagnosis usually starts with a cone beam scan. Cavitations cannot be seen on a conventional intraoral film; the claim depends on three-dimensional imaging, and practitioners describe it as a first-stage step rather than a response to a specific finding.

UK guidance does not support using it that way. The Faculty of General Dental Practice’s Selection Criteria for Dental Radiography, the standard reference for UK practice, states that there is “no evidence to support the use of CBCT routinely in these cases, nor any evidence of any improvement in patient outcomes when CBCT is used,” and cautions against localised CBCT examinations “becoming standard ‘defensive’ practice.” Health Protection Agency guidance sets the test narrowly: only examinations that “will provide extra information to aid the patient’s management or prognosis, and which cannot be gained from lower dose conventional imaging techniques, should be authorised,” and where the machine allows a choice, “the smallest volume size needed to answer the clinical question should be used.”

Under the Ionising Radiation (Medical Exposure) Regulations, a named practitioner has to justify each individual exposure — the scan has to be defensible for that patient, for a stated clinical question.

The doses involved are small in absolute terms. The FGDP puts a small field of view CBCT at 11–214 µSv against 2.7–38 µSv for a panoramic radiograph and 0.3–21.6 µSv for an intraoral film. But the comparison that matters is not with background radiation; it is with the lower-dose image that might have answered the same question, which is the comparison the guidance itself makes.

What this means when choosing a clinic

The answer to whether biological dentistry is evidence-based differs by treatment, which is why the question is worth asking treatment by treatment. Ceramic implants and metal-free restoration have guideline recognition. Elective removal of intact fillings and cavitation surgery currently do not. A clinic may offer both and describe them in the same terms.

There is also a practical division that the evidence discussion tends to miss. Of the seven treatments above, one is routinely available on the NHS, two are partially, and four are private-only. That is not a judgement on any of them — implants are private for reasons that have nothing to do with biological dentistry — but it does mean the treatments with the weakest evidence base are the ones a patient pays for directly.

Our guide to what biological dentistry is covers the underlying claims in more detail, and we have looked separately at Dr Dominik Nischwitz, the field’s most prominent advocate.