Dental tissue remineralization by bioactive calcium phosphate nanoparticles formulations

Abstract

Recent health care products are based on formulations claimed to provide enamel remineralization and dentinal tubules occlusion through calcium-phosphate bioactive nanocompounds (ion-doped hydroxyapatite and precursor, amorphous calcium phosphate nanoparticles). This study aimed to characterize, test, and compare for the first time the structure and performance of a representative, market-available sample of remineralizing toothpastes and topical mousses. Formulations were characterized to determine their composition and investigate the presence of bioactive compounds and doping elements. A conventional fluoride-containing toothpaste was used as reference. The enamel remineralization and efficacy of dentinal tubules occlusion by tested formulations were investigated ex vivo on human hard tissues. All formulations containing Ca-P bioactive nanocompounds showed remineralizing ability by epitaxial growth of a layer showing the morphology and composition of human hydroxyapatite. Such layers also embedded nanosilica clusters. The presence of doping elements or casein phosphopeptide seemed essential to allow such performances, especially when hydroxyapatite and amorphous calcium phosphate compounds were doped with small amounts of CO32−, F−, Mg2+, and Sr2+. Topical mousse formulations showed a higher tubules occlusion capability than toothpastes, independently from their composition. Therefore, all tested formulations could be useful in restoring tooth structures in a biomimetic way, contrasting dental demineralization processes leading to caries.

TEGDMA-Functionalized Dicalcium Phosphate Dihydrate Resin-Based Composites Prevent Secondary Caries in An In-Vitro Biofilm Model

“…Fluoride ions released from the material can directly inhibit the metabolic pathways of microbial cells in the overlying biofilm and accumulate at the surrounding hard tissue surfaces [30]. The latter leads to the precipitation of calcium fluoridelike deposits, which act as a reservoir and gradually release fluoride during decreased pH conditions [24,31]. The released fluoride prevents enamel demineralization and reduces caries susceptibility by incorporating fluoride into enamel hydroxyapatite via filling or displacing the hydroxyl vacancies, stabilizing the crystal structure forming fluorapatite and lowering the solubility product constant (Ksp).…”

TEGDMA-Functionalized Dicalcium Phosphate Dihydrate Resin-Based Composites Prevent Secondary Caries in an In Vitro Biofilm Model

“…Fluoride ions released from the material can directly inhibit the metabolic pathways of microbial cells in the overlying biofilm and accumulate on surrounding hard tissue surfaces [ 34 ]. The latter leads to the precipitation of calcium fluoride-like deposits, which act as a reservoir and gradually release fluoride during decreased pH conditions [ 27 , 35 ]. The released fluoride prevents enamel demineralization and reduces caries susceptibility.…”

“…Three randomly selected micrographs were obtained for each disk (500×, 2000×, and 5000×) for morphological observation of the surface and with the EDS probe (300 × 300 μm fields) in full-frame mode at 150 s acquisition time. The data acquired by EDS were averaged for each specimen and element, representing the wt.% distribution in a ≈1 μm superficial layer (See Ionescu et al, 2022, Figure 6 [ 27 ]). Elemental distribution at the surface level was visually displayed using the map mode (5000×), with an acquisition time of 600 s.…”

Calcium Phosphate Delivery Systems for Regeneration and Biomineralization of Mineralized Tissues of the Craniofacial Complex

“…To make ACP-PILP more translatable, groups have evaluated ACP-PILP embedded in dental topical formulations, adhesives, or self-setting materials. − An interesting approach developed by Shi et al was based on a mineralized adhesive containing PASP-stabilized PILPs . Here, they showed that ACP-PILPs could be immersed in the etching material with minimal agglomeration and when applied to etched dentin surfaces, they significantly reduced dentin permeability.…”