New discovery of mineralized dental coating can help restore tooth enamel

Russia: Adding a complex of amino acids to the mineralized material hydroxyapatite can help restore tooth enamel, a recent study in Results in Engineering has shown. The research was undertaken jointly by scientists at Voronezh State University, Ural Federal University, Al-Azhar University, National Research Center (Egypt), and Voronezh State Medical University. 

Tooth enamel has a protective function, but its integrity can be destroyed by microfracture, erosion, abrasion, or to the point that if the tissue is not repaired in time, the enamel lesion will impact the dentin and then the tooth's pulp. Current tooth restorative techniques include enamel acid etching to boost the bonding effect, which sometimes leaves behind products which not always may have a positive effect on the bonding of enamel and synthetic materials. 

Hydroxyapatite is a major component of human bones and teeth. Mixing it with polar and polyfunctional organic amino acids can generate a dental coating that recreates the microstructure and composition of natural tooth enamel. The new dental restoration technique can be used to lessen the teeth's sensitivity in case of enamel abrasion or restore it after erosion. 

The new composition material duplicates the features of the tooth's surface at the structural and molecular level and surpasses the strength of the native enamel. 

Pavel Seredin from Ural Federal University in Yekaterinburg, Russia, and colleagues considered the problem of engineering a biomimetic mineralized layer on the surface of native dental tissue (bio-template). 

Using nano crystalline carbonate-substituted calcium hydroxyapatite (HAp), calcium alkali, and a complex of polyfunctional organic and polar amino acids helped to form the mineralized layer on a biotemplate. 

By applying the set of spectroscopic and structural methods of analysis, the authors confirmed the formation of a layer of mineralized biomimetic HAp on the surface of bio-template with properties like those of natural hard tissue. "The thickness of the biomimetic mineralized layer varied from 300 to 500 nm, while the direction of some ncHAp nanocrystals coincides with that of the enamel's apatite crystals," the researchers stated.

"We also demonstrated that the engineered mineralized layer of HAp was characterized by homogeneous micromorphology and enhanced nano hardness in the region of the enamel rods exceeding those of native enamel."

"Developing a strategy for biomimetic engineering and a technique for enamel surface pre-treatment for enabling tissue mineralization has huge potential in dental applications," they conclude. 

Reference:

The study, "Engineering of biomimetic mineralized layer formed on the surface of natural dental enamel," was published in Results in Engineering. 

DOI: https://doi.org/10.1016/j.rineng.2022.100583