P11-4 / Curodont: What It Is, Does It Work?

P11-4 at a glance

Not injected — read this first

P11-4 has no human injectable use, no injection dose and no injection safety data. It is applied to a prepared tooth surface by a dentist or a hygienist working on a dentist's prescription. Nothing on this page describes reconstitution or injection, because no such protocol exists for this compound.

What it is

An 11-residue rationally designed self-assembling peptide, Ac-Gln-Gln-Arg-Phe-Glu-Trp-Glu-Phe-Glu-Gln-Gln-NH2 (QQRFEWEFEQQ), CAS 593266-60-5, listed on cosmetic and drug labels under the INCI name oligopeptide-104. It is a structural biomaterial with no receptor, no systemic target and no endogenous human counterpart.

Brand names

Marketed as Curodont Repair (EU and Switzerland) and Curodont Repair Fluoride Plus (United States), both applied by a dental professional, and as Curodont Protect, a consumer dentifrice whose US label lists stannous fluoride as the active ingredient and oligopeptide-104 among the inactive ingredients. The underlying self-assembling-peptide platform is branded Curolox Technology. Invented and patented at the University of Leeds, licensed to credentis AG in Switzerland, now sold under the vVARDIS brand. Those are third-party trademarks. Medibact is not affiliated with, endorsed by, sponsored by or reselling any of them.

What it is used for

Guided remineralization of early, non-cavitated enamel caries and white-spot lesions, including the chalky white marks that develop around orthodontic brackets. It is not a treatment for a cavity that has already broken through the enamel surface.

How it is applied

In a dental chair, as part of a single appointment: the tooth is cleaned by prophylaxis, the lesion is conditioned and then etched so the peptide can pass through the intact surface layer, and the peptide solution is applied and left in place long enough to diffuse into the lesion body and assemble there. Fluoride varnish usually follows. Home-use gel and toothpaste formulations of the peptide also exist and are sold through ordinary retail channels.

Evidence status

Stronger human evidence than most compounds in peptide catalogues, with real caveats. A 2023 JADA systematic review and meta-analysis of six trials found substantially more caries arrest (relative risk 1.82, 95% CI 1.32-2.50; number needed to treat 2.8) and a mean 32% reduction in lesion size — while stating that all six trials carried elevated risk of bias and two used non-masked assessors. Two independent randomized trials did not place it ahead of modern fluoride varnishes.

Regulatory status

CE-marked as a medical device in the EU and Switzerland, permitting dentist use for early caries. In the United States the marketed product is an over-the-counter monograph anticaries drug whose recognized ACTIVE ingredient is sodium fluoride 0.05%; oligopeptide-104 appears among the INACTIVE ingredients with no stated amount. P11-4 itself holds no FDA approval and no identified 510(k) clearance.

Half-life

Not established, and not a meaningful parameter for this compound. There is no human pharmacokinetic data because it is never given systemically. The only retention data come from laboratory models, which report that a portion of the applied peptide remains inside the lesion as assembled scaffold.

Sport

Not on the WADA Prohibited List, including the 2026 List effective 1 January 2026, and there is no plausible basis for listing it — a topically applied dental material with no hormonal, metabolic or ergogenic mechanism does not fall under S2 or any other class.

Availability and what Medibact sells

Obtained through a dental practice, not sold to consumers as a standalone compound. Raw P11-4 is sold research-use-only by laboratory suppliers, explicitly not for human use. Medibact sells USP-grade bacteriostatic water and digital educational guides. Medibact does not sell peptides, and specifically does not sell P11-4 or any Curodont product.

Reported ranges from research/community — examples, not recommendations.

What it is / mechanism

P11-4 is a biomaterial rather than a signalling peptide, and that single distinction governs everything else about it. It binds no receptor, activates no pathway, has no systemic target and has no endogenous human counterpart. It is an eleven-residue sequence — Ac-Gln-Gln-Arg-Phe-Glu-Trp-Glu-Phe-Glu-Gln-Gln-NH2, written QQRFEWEFEQQ, CAS 593266-60-5 — that was designed at the University of Leeds to do one physical thing extremely reliably: assemble itself into a fibrous three-dimensional matrix when, and only when, it encounters a particular set of chemical conditions. Those conditions are the ones found inside an early enamel lesion. Enamel demineralizes from the inside first: acid produced by plaque bacteria dissolves mineral in the subsurface body of the enamel while the outermost layer stays comparatively intact, leaving a porous, chalky, still-unbroken white area. That is what a white-spot lesion is, and that porous subsurface body is the target. P11-4 is supplied to the dentist as a monomeric solution — the peptide is held in its unassembled, free-flowing form, thin and mobile enough to diffuse through the pores of the intact surface layer and into the lesion body. The trigger waiting inside the lesion is the lesion's own chemistry. A demineralized lesion is an acidic, ion-rich microenvironment, and it is that combination — low pH together with the elevated ionic strength of the dissolved mineral around it — that switches the peptide from monomer to matrix. Hierarchical self-assembly follows in stages: individual monomers align into antiparallel beta-sheet tapes, tapes stack into ribbons, ribbons into fibrils, and fibrils into fibres. Those stages proceed in that order, the lowest-order tapes forming first and the higher-order fibres taking longest to develop; no timescale is given here, because the published assembly kinetics come from laboratory systems rather than from a treated tooth. The result is a scaffold that structurally mimics the enamel matrix protein assemblies present when a tooth is first mineralized during development. The direction of that pH trigger is worth stating explicitly, because it is frequently reported backwards. Assembly is switched on by acid, not by neutralization. The same acidity that created the lesion is what causes the peptide to gel and lock into place precisely where the damage is, and this is the whole basis of the design: the material is inert and mobile everywhere else in the mouth and becomes a solid scaffold only in the diseased volume. Assembly is pH-controlled, which is what gives the manufacturer control over where and when the matrix forms. The assembled fibres carry regularly spaced anionic glutamate domains along their surfaces, and these act as high-affinity calcium nucleation sites. Calcium and phosphate ions already dissolved in saliva are captured at those sites, and hydroxyapatite crystals nucleate and grow de novo from within the lesion outward. This is the point most consumer coverage of Curodont gets wrong. P11-4 donates no mineral whatsoever. It contains no calcium, no phosphate and no fluoride. It is a nucleation template, and it is entirely dependent on the patient's own saliva to supply the raw material — which is also why saliva quality, diet and oral hygiene remain the limiting factors in whether the approach works for a given person. A secondary contribution is purely physical: the assembled matrix occludes lesion porosity, reducing the diffusive loss of mineral back out of the lesion. Laboratory work indicates that a portion of the applied peptide is retained inside the lesion as scaffold rather than being lost from it. The rationale offered for why this differs from fluoride is spatial rather than chemical. Topical fluoride acts predominantly at the lesion surface, promoting formation of acid-resistant fluorapatite and tending to seal the outer layer; the mechanistic argument for P11-4 is that it seeds mineral growth throughout the body of the lesion instead. The two are not framed as competitors by the manufacturer — in the clinical trials and in the US formulation, the peptide is used alongside fluoride rather than instead of it. One technical footnote is worth stating plainly, because it is central to why this compound is not a candidate for systemic use. The assembled, functional form of P11-4 is an engineered amyloid-like beta-sheet fibril. That structure is exactly what makes it work inside acellular enamel, where there are no cells to interact with it. It is also precisely the property that makes systemic administration a non-starter, and nobody has developed it for that purpose. There is no research programme, no trial and no published human data on parenteral P11-4 of any kind.

Researched effects

What P11-4 is meant to accomplish is narrow and specific: arrest and partial reversal of early enamel caries, without a drill and without removal of tooth structure. In practical terms the outcomes reported in trials fall into three categories. First, lesion activity — an active, chalky, rough white-spot lesion becoming inactive and hard on clinical assessment. Second, lesion size and mineral content — measurable shrinkage of the lesion area and increased mineral density on quantitative light-induced fluorescence, laser fluorescence or radiographic assessment. Third, appearance — white spots becoming less visually obvious as the enamel behind them regains mineral and its refractive index moves back toward that of sound enamel. That third outcome is the one patients care about most and the one most likely to disappoint if expectations are not set carefully. Improvement in appearance is gradual, takes weeks to months as remineralization proceeds, and is partial rather than total in most reported cases. The mean lesion-size reduction across the pooled trials was 32%, with a standard deviation of 28% — a wide spread that reflects genuine variation in how individual lesions respond. This is not a cosmetic whitening product, it does not affect the colour of sound enamel, and it does nothing for staining, fluorosis or intrinsic discolouration. The boundary of its usefulness is sharp and clinically important. P11-4 targets non-cavitated lesions, meaning the enamel surface must still be structurally intact. Once a lesion has cavitated — once the surface has collapsed and there is an actual hole — the porous diffusion pathway that the whole mechanism depends on no longer behaves the same way, and conventional restorative treatment is what is indicated. That is a determination a dentist makes by examination and radiograph, and it is the reason this is a prescribed clinical procedure rather than a consumer product. The pooled trial data reflect this boundary honestly: the meta-analysed reduction in cavitation had a confidence interval that crossed 1 (relative risk 0.32, 95% CI 0.10-1.06), so the claim that it prevents lesions from progressing to cavitation remains suggestive rather than established. The most consistent finding across the trial base is the one on caries arrest, and it is a real effect: pooled relative risk 1.82 for lesion arrest with a number needed to treat of 2.8, meaning fewer than three lesions treated for one additional arrested lesion compared with control. A 2024 randomized trial in Clinical Oral Investigations reported substantially less lesion progression with the peptide-plus-fluoride product than with sodium fluoride varnish over six months. A triple-blind trial published in BMC Oral Health in 2026, of a home-use peptide-plus-fluoride gel used during fixed orthodontic treatment, found initial lesions on 7.2% of surfaces versus 14.5% with the control gel over eighteen months. What P11-4 does not do is equally worth stating. It does not regrow enamel that has been lost to cavitation or fracture, it does not replace fillings, it does not treat dentine caries, it does not affect gum disease, and it has no systemic effect of any kind — no metabolic, hormonal, recovery, cognitive, cosmetic or performance action. Every clinical effect attributed to it happens inside a few hundred microns of one tooth surface.

Dosage — reported ranges (overview)

There is no dose of P11-4 in the pharmacological sense, and framing it as one is the most common category error made about this compound. What exists is a single-lesion topical application delivered as part of a clinical procedure, and what governs the outcome is the surface preparation and the patient's saliva, not the quantity of peptide. In outline, the procedure runs as follows. The tooth is cleaned by prophylaxis. The dentist then conditions the lesion to clear organic material out of its pores and etches the surface so that the peptide can pass through the intact outer layer, after which the surface is rinsed and dried. The peptide solution is applied to the prepared lesion and left in place long enough to diffuse into the lesion body and assemble in situ, and fluoride varnish typically follows. The US presentation, Curodont Repair Fluoride Plus, is a two-unit kit whose components are combined at the chairside and then pressed against the prepared lesion, after which the patient is asked to avoid rinsing, eating and drinking for a short period. Reapplication regimens in the published trials ranged from a single application, to a repeat several months later, to one arm using repeated applications of the peptide matrix. Home-use gel formulations combining P11-4 with approximately 900 ppm sodium monofluorophosphate were applied twice weekly after brushing over eighteen months in the BMC Oral Health orthodontic trial. That outline is given to explain what the appointment involves, deliberately without the reagents, concentrations and timings that would make it a reproducible recipe. Those details belong in the manufacturer's instructions for use and in a clinician's training, not on a consumer explainer, because the procedure involves caustic conditioning and etching agents applied to a tooth immediately adjacent to gingival and other soft tissue, after a clinical determination that the lesion is genuinely non-cavitated and appropriate for the approach. Regulators treat it accordingly. The North Carolina State Board of Dental Examiners published an interpretive statement dated 18 October 2024, addressing whether application of Curodont may be delegated by a dentist to a dental hygienist; it concluded that a hygienist may apply it, but only following prophylaxis and only where a dentist has examined the patient and prescribed the treatment. That statement is publicly available on the board's website, and it is a useful illustration of how the procedure is classified: a dentist-prescribed clinical act. Attempting any part of it outside a dental setting would be both unsafe and, in most jurisdictions, the unlicensed practice of dentistry. For completeness on the research-supply side: raw lyophilized P11-4 is sold research-use-only by laboratory chemical suppliers and is explicitly labelled not for human use. Suppliers issue benchwork handling guidance with that material for in vitro experiments; those figures are laboratory parameters for cell-free and cell-culture work, they are not reproduced anywhere on this page, and they are not dosing information of any kind. There is no reported human injection dosing for this compound at any quantity, by any route, in the published literature or in community practice, and no number from a laboratory or animal setting translates into one.

The full step-by-step protocol examples, titration schedule, and a printable protocol sheet with a dosing and injection log are included in the paid Protocol Playbook for this guide.

Reconstitution — not applicable

This page deliberately contains no reconstitution table, and that is not an omission. P11-4 is not reconstituted with bacteriostatic water and it is not injected. It arrives at a dental practice as a finished, ready-to-use product — a two-unit kit or a pre-formulated gel or dentifrice — and it is applied to a prepared tooth surface. There is no vial to mix, no concentration in micrograms per millilitre to calculate, no insulin-syringe unit conversion, and no injection volume, because none of those quantities exist for this compound in humans. Every other compound covered on this site is reconstituted and drawn up, and it would be easy to assume the same arithmetic applies here. It does not, and publishing worked numbers would create exactly the wrong impression: that somewhere there is a subcutaneous P11-4 protocol waiting to be dosed correctly. There is not. No regulator has approved P11-4 for injection or systemic administration anywhere in the world; no human trial has used any route other than topical application in the mouth; and there is no human pharmacokinetic or systemic safety data against which any injection quantity could be judged safe or unsafe. Research-use-only material sold by laboratory suppliers is intended for benchwork and is labelled not for human use. This page also holds to that consistently rather than only in this section: no concentration, no solvent figure and no preparation parameter for the raw peptide appears anywhere in this guide, in the mechanism section, the storage notes or the discussion of laboratory and animal work. Readers who arrived from a reconstitution-focused search are in the right place for information and the wrong place for a mixing protocol. The bacteriostatic water calculator is likewise absent on purpose: bacteriostatic water has no role in the use of this compound. What follows covers what P11-4 is, what the dental evidence shows, and how the product is regulated.

Injection / administration basics

Not applicable, and stated as an absence rather than presented as a clean record. P11-4 is not injected in humans. There is no subcutaneous, intramuscular, intravenous or any other parenteral protocol for this compound in the published literature, in any regulatory filing, in any clinical trial, or in reported community practice. There is no needle gauge, no site rotation convention, no injection frequency and no reported experience, because the route does not exist. The closest thing in the whole record is preclinical and strictly local: a rat study in which a hydrogel form of the peptide was placed into surgically created periodontal defects, where the material acted as a scaffold occupying a defect rather than as a drug distributed through the body. A broader preclinical literature exists on P11-family self-assembling peptide hydrogels as locally placed scaffolds for bone and cartilage tissue engineering, and it follows the same pattern — in vitro or small-animal, always sited locally in a defect, never given systemically, never in humans. The formulation details of that work are laboratory parameters for animal surgery and are not reproduced here, because they carry no transferable meaning for a person and every reason to be misread as though they did. There is a specific reason this gap matters more here than it would for an ordinary understudied peptide. The functional form of P11-4 is not the monomer in the applied solution; it is the assembled, engineered amyloid-like beta-sheet fibril that forms when the monomer meets the acidic, ion-rich conditions inside a lesion. A peptide designed to switch from free monomer to fibrillar solid in response to local chemistry is a fundamentally different proposition in a systemic compartment than it is inside acellular enamel, where there are no cells for it to interact with. Nothing can be said about how that would behave in humans, favourably or unfavourably, because it has never been studied. Absence of evidence about parenteral exposure is not evidence of safety, and the excellent tolerability record described elsewhere on this page belongs entirely to topical dental application and does not transfer to any other route.

Half-life & frequency rationale

Not established, and not a meaningful parameter for this compound. There is no published human pharmacokinetic data for P11-4 — no plasma half-life, no Cmax, no clearance, no volume of distribution — for the straightforward reason that it is never administered systemically and its systemic absorption has never been characterized. Any figure quoted as a half-life for P11-4 has been invented or borrowed from an unrelated peptide. The parameter that actually matters for a scaffold biomaterial is retention at the site of action, not clearance from plasma, and there the literature offers only laboratory observations: in artificial-lesion models a portion of the applied peptide is retained within the lesion as assembled scaffold. The scaffold is intended to persist inside the lesion over the weeks during which remineralization proceeds, which is why clinical outcomes are assessed at three, six, twelve and eighteen months rather than in hours. The manufacturer's safety rationale for the fraction that is not retained is that swallowed material is broken down to its constituent amino acids or excreted — a reasonable expectation for a short peptide passing through the gut, though it is a rationale rather than a measured pharmacokinetic result. The practical takeaway is that duration of action for P11-4 is a question about how long a mineral scaffold survives inside a tooth, not a question about circulating concentrations, and it should not be compared with the half-life figures published for systemic peptides.

Stacking — overview

P11-4 is not stacked, and the concept does not transfer to it. Stacking is a framework for systemic signalling compounds, where two agents acting on related pathways might produce additive or complementary effects somewhere in the body. P11-4 has no pathway, no receptor and no systemic distribution. It is a structural scaffold that assembles inside one lesion on one tooth and nucleates mineral there. Nothing that circulates in the bloodstream interacts with it, and combining it with a systemic peptide would be combining two unrelated things that never meet. What does exist is co-formulation and sequencing within a dental treatment plan, which is a different concept. Fluoride varnish is routinely applied immediately after the peptide in both the trials and clinical practice — not as a synergistic stack in the peptide sense, but because the two act at different depths and the peptide depends on salivary mineral supply that fluoride helps preserve. The US product is formulated with sodium fluoride as its recognized active ingredient and chlorhexidine digluconate among its inactive ingredients alongside the peptide. The home-use gel tested in the orthodontic trial combined the peptide with roughly 900 ppm sodium monofluorophosphate, and Curodont Protect is a consumer dentifrice whose US label lists stannous fluoride as the active ingredient and oligopeptide-104 among the inactive ingredients. All of those are decisions made by a formulator or a treating dentist about a coherent oral-care regimen, not selections a user assembles. It is also worth naming what would genuinely improve outcomes with this compound, since that is what a stacking question is usually reaching for: the peptide draws its calcium and phosphate from saliva, so salivary flow, dietary sugar frequency, plaque control and any medication or condition causing dry mouth all bear directly on whether remineralization proceeds. Those are the real co-factors, and they are conversations for a dental professional rather than additions to a protocol.

For how combinations are grouped by research context, the named blends, and why a pre-mixed blend vial cannot be calculated from its total milligrams, see the peptide stacks guide.

Storage & handling

• No patient-side storage question arises for the clinical product. Curodont Repair and Curodont Repair Fluoride Plus are supplied as sealed single-use kits held by the dental practice and applied in the chair, and storage and shelf-life follow the manufacturer's labelling and the practice's own materials handling — not anything a patient does at home.
• Home-use formulations — the peptide-plus-monofluorophosphate gel tested in the orthodontic trial, and Curodont Protect, a consumer dentifrice whose US label lists stannous fluoride as the active ingredient and oligopeptide-104 among the inactive ingredients — are ordinary consumer oral-care products stored according to their own package labelling, in the same way as any toothpaste or dental gel.
• Bacteriostatic water plays no part in the handling of this compound at any stage. It is not reconstituted, so the benzyl-alcohol preservative logic that governs multi-withdrawal peptide vials is simply not relevant here, and none of Medibact's bacteriostatic water guidance applies to P11-4.
• Research-use-only lyophilized P11-4 sold by laboratory suppliers is stored and handled according to that supplier's certificate of analysis and safety data sheet. It is labelled explicitly not for human use, the guidance issued with it is benchwork guidance for in vitro experiments rather than a preparation protocol for anything given to a person, and no part of it is reproduced on this page.
• The reason the marketed product ships finished rather than as a powder to be mixed is the peptide's defining property: it is engineered to stay unassembled until it meets the conditions inside a lesion, and holding it reliably in that unassembled state is a formulation problem the manufacturer has solved in the factory. That is why the dental product exists as a ready-to-use unit, why there is nothing for a practice or a patient to prepare, and why no mixing step exists anywhere in its legitimate use.

Guide FAQ

Quick answers about guide scope, access, and educational use context.