Hydroxyapatite (HAP)

2022: Scientists suggest using scallop shell in dentistry

An international team of scientists with the participation of NITU MISIS researchers received material for restorative surgery from the shell of the Nodipecten nodosus scallop. It is safe for the body and has high antibacterial properties. In the future, the material can be used in dentistry and maxillofacial implantology. The institute announced this on December 13, 2022.

As of December 2022, infection of medical implants remains one of the main problems in orthopedic and dental operations. An emerging complication - inflammation around the implant often requires concomitant drug therapy, but this often leads to side effects due to the characteristic properties of antibiotics and their high doses.

Such a problem can be solved using biomaterials with antibacterial activity, in particular on the basis of hydroxyapatite (HAP), which is a mineral component of bone tissue and tooth enamel. This material has biocompatibility and bioactive properties, can be easily integrated into bone tissue and adjacent tissue areas.

An international team of scientists from Russia, India and the Republic of Korea, led by Gopalu Karunakaran, has been studying the production of this biomaterial from various types of raw materials and improving its characteristics for several years. Recently, researchers introduced a method for the synthesis of highly pure biocompatible hydroxyapatite with improved antibacterial properties from biosolids - scallop shell (Nodipecten nodosus).

According to preliminary data, hydroxyapatite with scallop shell may exhibit higher antibacterial properties than the similar material to the blue mussel, which the team of researchers presented earlier. However, as scientists note, further research will be required to refine and compare materials from biological waste in detail.

Using the microwave hydrothermal synthesis method, hydroxyapatite samples were obtained in the form of mesoporous nanorods. As precursors - substances leading to the formation of the desired substance, scallop shells, calcium phosphate and cetrimonium bromide were used. Zinc-doped hydroxyapatite nanorods have demonstrated remarkable antibacterial properties in relation to anthropoid pathogenic bacteria Klebsiella pneumoniae (MTCC 7407) and Bacillus subtilis (MTCC 1133), and with an increase in zinc concentration, antibacterial properties increase. Moreover, these materials are completely non-toxic, - said Evgeny Kolesnikov, co-author of the work, employee of the Department of Functional Nanosystems and High-Temperature Materials of NITU MISIS.

Scientists conducted toxicity studies of the material using biological test objects - Zebrafish.

In the future, the scientists plan to continue to investigate the influence of various additional modifiers on the antibacterial properties of hydroxyapatite, as well as increasing the variety of biofeeds used to synthesize highly pure biocompatible hydroxyapatite.