Restoring Tooth Enamel: A Breakthrough in Regenerative Dentistry

Tooth enamel is the hardest substance in the human body; it is tougher than bone and protects our teeth every day from wear and tear due to chewing, grinding, and exposure to acids. But when enamel is lost, it doesn't grow back, and as a result, its resistance to deterioration also diminishes (1^✔ ✔Trusted Source
Biomimetic supramolecular protein matrix restores structure and properties of human dental enamel

Go to source). Enamel erosion is caused by acidic foods, bacterial colonies, and even over-brushing. Almost half of the world population is exposed to enamel erosion, for which the economic spending alone stands at approximately US $544 billion each year.

Dentists so far could only provide a temporary solution through fillings, veneers, or fluoride treatments, none of which could actually restore enamel!

A New Hope In Restoring Lost Enamel: Biomimetic Protein Matrix

Scientists under the guidance of Professor Alvaro Mata and others from several institutions have designed a biomimetic supramolecular protein matrix capable of regenerating enamel-like tissue and rebuilding its strength and resilience.

This innovation is built on elastin-like recombinamers (ELRs), which are synthetic proteins designed to mimic the behaviour of amelogenin (a natural protein responsible for enamel formation during initial stages of tooth development).

The ELR-based coating, when applied to eroded teeth, showed the following results:

• Simulated the natural process of forming enamel.
• Promotes the growth of apatite nanocrystals (the mineral crystals that make enamel strong).
• Recreates the hierarchical layers of real enamel, from the outer aprismatic layer to the deeper prismatic zones.

How the New Enamel Works: Recreating Nature’s Design

The blueprint of this research is purely based on the very nature of enamel. Natural enamel develops through a protein framework known as amelogenin, which acts like a guide to calcium and phosphate ions to form as organised nanocrystals. The researchers replicated this, using a fibril-rich ELR matrix containing special hydrophobic, hydrophilic, and acidic sequences to form fibres on their own in the presence of calcium ions.

Layer-by-Layer Enamel Regrowth

When applied as a thin coating (2-10 μm) to etch or erode enamel:

• The matrix initiates epitaxial growth – i.e., new crystals are produced from the existing old ones.
• The formed layers resemble the microarchitecture of the natural enamel regions (aprismatic, prismatic, and inter-prismatic).

This ELR system can also be done in 3-4 minutes, unlike previous methods that necessitated either the use of toxic chemicals or extended applications (of lab materials), since it only needs materials that are present in dental offices (ethanol, glutaraldehyde, and calcium ions).

Stronger Than Before: Enamel Fully Restored

The enamel, which had been acid-damaged previously, prior to treatment, had lost the bulk of its strength; it was weak and tender, resembling chalk.

• Flexibility (Young's modulus): Reduced to approximately 37 GPa.
• Hardness: It is only 1.1 GPa, which implies that it can be easily worn or broken.

After applying the new ELR protein coating, the enamel grew nearly as vigorously as healthy natural enamel:

• Flexibility: Rose to 76 GPa
• Hardness: Had gone up to 3.1 GPa (nearly fully restored).

Even more impressively, the repaired enamel could withstand friction and wear more than the natural enamel.

• The surface became smoother, and the friction was cut down to 0.29.
• The overall wear strength, which is the degree of its resistance to damage, rose by about 92 GPa to 171 GPa, which is higher than the 153 GPa of normal enamel!

In simple terms, the new layer did not merely seal the tooth, but it also made it more durable, smoother and tougher than previously.

Beyond Healing Enamel, Healing the Dentine Too!

The ELR coating (even when enamel was lost entirely, and the underlying dentine was also revealed) was capable of:

• Infiltrating the collagen net of dentine.
• Forming mineral layers that are similar to enamel on its surface.
• Restoring the dentine-enamel junction of natural teeth.

The two aspects of this capacity provide the potential to one day assist patients with severe cases of enamel erosion or hypersensitivity.

The researchers tested the newly developed enamel with real-life stresses that could cause wear and tear for the natural enamel:

• 1 year of brushing teeth: No structural damage.
• Chewing and grinding (75 N force) for 3.5 years: equivalent wear resistance of natural enamel.
• Acidic beverages (pH 4.0 acetic acid): More resistant to erosion in comparison with untreated enamel.
• Human saliva tests: In the saliva of different donors, the coating demonstrated remarkable efficacy, and under real-world circumstances, enamel regeneration was consistent.

The ELR coating was also stable even at extreme temperatures, pH and brushing, thus demonstrating great stability.

What Importance Does Restoring Enamel Hold?

This study would be a paradigm shift in restorative dentistry. Instead of giving a patchwork to the lost enamel, in the near future, dentists will be able to regenerate it biologically, which can restore enamel’s natural form and functionality.

In a situation where they are taken to clinics, this biomimetic method could:

• Lessen dental erosion and sensitivity.
• Provide a quick, safe and least invasive treatment.
• Improve oral health services worldwide, particularly in countries with limited access to quality dental care.

Towards a Regenerative Future With Enamel Regeneration

It was thought to be impossible to regenerate functional enamel, but the research shows that it is possible.

The biomimetic ELR matrix can restore enamel's strength, toughness, and chemical resistance in addition to regenerating its intricate nanostructure.

Even though in vivo (live patient) research is still pending before clinical implementation, this innovation is a significant step towards self-healing teeth and regenerative dentistry in the future. The authors conclude that their approach has immense potential in clinical practice and also presents promising opportunities for bio-inspired materials that could enable bio-inspired enamel to work again.

Reference:

1. Biomimetic supramolecular protein matrix restores structure and properties of human dental enamel - (https://www.nature.com/articles/s41467-025-64982-y)

Source-Medindia