New Tooth Engineered Coating Stronger Than Enamel

Scientists in Russia  have perfected hydroxyapatite, a material for mineralizing bones and teeth. By adding a complex of amino acids to hydroxyapatite, they were able to form a dental coating that replicates the composition and microstructure of natural enamel. Improved composition of the material repeats the features of the surface of the tooth at the molecular and structural level, and in terms of strength surpasses the natural tissue. The new method of dental restoration can be used to reduce the sensitivity of teeth in case of abrasion of enamel or to restore it after erosion or improper diet.
Hydroxyapatite is a compound that is a major component of human bones and teeth. Scientists selected a complex of polyfunctional organic and polar amino acids, including, for example, lysine, arginine, and histidine, which are important for the formation and repair of bone and muscle structures. The chosen amino acids made it possible to obtain hydroxyapatite, which is morphologically completely similar to apatite (the main component of tissues) of dental enamel. The researchers also described the conditions of the environment in which the processes of binding of hydroxyapatite to the dental tissue should occur. Only if these conditions are met it is possible to fully reproduce the structure of natural enamel.

Traditionally in dentistry, composite restorative materials are used in enamel restoration. To increase the bonding efficiency of enamel and composite, the restoration technique involves acid etching of the enamel beforehand. The etching products left behind may not always have a positive effect on the bonding of enamel and synthetic materials. To reproduce the enamel layers with biomimetic techniques, we neutralized the media and removed the etching products using calcium alkali. In this way we improved the binding of the new hydroxyapatite layers,” explains Pavel Seredin.
The formation of a mineralized layer with properties resembling those of natural hard tissue was confirmed by field emission electron and atomic force microscopy as well as by chemical imaging of surface areas using Raman microspectroscopy. The study was conducted on healthy teeth to eliminate the influence of extraneous factors on the resulting layer and to be able to compare the results with healthy teeth. Next, the researchers will tackle the challenge of repairing larger defects, which can be of varying nature from the initial stages of caries to cracks and volumetric fractures.

The joint research was conducted by scientists from the Research and Education Center “Nanomaterials and Nanotechnologies” of Ural Federal University, Voronezh State University, Voronezh State Medical University, Al-Azhar University, and the National Research Center (Egypt).

The study and experimental results are published in Results in Engineering.

Source: https://urfu.ru/

Stem Cells Restore Damaged Teeth

A new study demonstrates that stem cells from baby teeth can be used to repair damaged permanent teeth in young children. The findings suggest a new treatment for childhood dental issues may be around the corner. The treatment’s potential applications go much further than just dental health. Half of all children suffer some kind of dental injury while young. Sometimes the damage isn’t to the baby teeth they will lose anyway, but to the permanent adult teeth lying below the gums that they will need for the rest of their lives. In some cases, trauma can cut off the blood supply to a tooth and rot out the living pulp inside it; a condition called “pulp necrosis.” This condition often leads to the loss of the tooth. While treatment exists, it is often unsatisfactory.

A new clinical trial by Yan Jin, Kun Xuan, and Bei Li of the Fourth Military Medicine University in Xi’an, China and Songtao Shi of the University of Pennsylvania‘s School of Dental Medicine demonstrates how to repair teeth suffering from pulp necrosis by taking stem cells from the patient’s baby teeth.

The study, carried out in China on 40 children who had both damaged adult teeth and baby teeth that had yet to fall out, was published in the journal Science Translational Medicine. The test subjects were selected to either receive the new treatment or an older treatment called apexification, which attempts to address the issue by encouraging root development. This was considered the control group.

The patients who received the stem cell treatment, called human deciduous pulp stem cell (hDPSC) treatment, had pulp tissue taken out of one of their healthy baby teeth. This pulp is rich in stem cells. The cells were grown in a lab and then placed into the injured adult tooth. The hope was that the stem cells would encourage the growth of new pulp inside the tooth.

Follow-ups were carried out for up to three years. The patients who had received the hDPSC treatment showed better blood flow in their teeth, better root systems, and thicker dentin than the patents who underwent the traditional procedure. They also had recovered sensation in their teeth, while the control group had not. The use of a patient’s own cells in the treatment also reduced the risk of their body rejecting the therapymaking the concept even more attractive. “This treatment gives patients sensation back in their teeth. If you give them a warm or cold stimulation, they can feel it; they have living teeth again,” Dr. Shi told Penn Today. “For me, the results are very exciting. To see something we discovered take a step forward to potentially become a routine therapy in the clinic is gratifying.

Source: https://penntoday.upenn.edu/