Two-in-one strategy: a remineralizing and anti-adhesive coating against demineralized enamel

Abstract

Tooth enamel is prone to be attacked by injurious factors, leading to a de/remineralization imbalance. To repair demineralized enamel and prevent pulp inflammation caused by biofilm accumulation, measures are needed to promote remineralization and inhibit bacterial adhesion on the tooth surface. An innovative material, poly (aspartic acid)-polyethylene glycol (PASP-PEG), was designed and synthesized to construct a mineralizing and anti-adhesive surface that could be applied to repair demineralized enamel. A cytotoxicity assay revealed the low cytotoxicity of synthesized PASP-PEG. Adsorption results demonstrated that PASP-PEG possesses a high binding affinity to the hydroxyapatite (HA)/tooth surface. In vitro experiments and scanning electron microscopy (SEM) demonstrated a strong capacity of PASP-PEG to induce in situ remineralization and direct the oriented growth of apatite nanocrystals. Energy dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD) and Vickers hardness tests demonstrated that minerals induced by PASP-PEG were consistent with healthy enamel in Ca/P ratio, crystal form and surface micro-hardness. Contact angle tests and bacterial adhesion experiments demonstrated that PASP-PEG yielded a strong anti-adhesive effect. In summary, PASP-PEG could achieve dual effects for enamel repair and anti-adhesion of bacteria, thereby widening its application in enamel repair.

Influence of ER-CR-YSGG Laser and Photodynamic Therapy on the Dentin Bond Integrity of Nano-Hydroxyapatite Containing Resin Dentin Adhesive: SEM-EDX, Micro-Raman, Micro-Tensile, and FTIR Evaluation

“…HA is a slowly resorbing, non-toxic, bioactive, and biocompatible material [10]. The presence of HA in a material promotes the biomimetic mineralization of dental tissues [11]. Among nanomaterials, the nano-HA particles have a similar crystal structure as that of the apatite present in the hard tissues of humans [12] and have been successfully used for various medical applications related to bone tissue engineering [13].…”

Dental Materials for Oral Microbiota Dysbiosis: An Update

“…In view of the abundant existence of Ca 2+ ions on the tooth surfaces, modifying polymers with groups that can interact with these ions has been an alternative. For example, Hou et al synthesized a highly hydrophilic diblock copolymer polyethylene glycol-poly (aspartic acid) (PEG-PAsp), where carboxyl groups in the PAsp segments provide binding sites with Ca 2+ on the enamel surfaces, so that PEG segments on the other side can inhibit S. mutans and Stoeptococcus sanguis (S. sanguis) adhesion on the enamel (Hou et al, 2020). Compared with carboxyl groups, PO 3− 4 groups are equipped with stronger ability to bind with Ca 2+ .…”

Bio-inspired special wettability in oral antibacterial applications

“…The polymers can be adsorbed to negatively charged metallic oxide spontaneously, such as titanium or niobium oxide surfaces, to form a stable, densely packed PEG monomolecular adlayer to reduce the adhesion of bacteria ( Harris et al, 2004 ). Poly (aspartic acid)-polyethylene glycol (PASP-PEG) was synthesized by a similar method with high affinity for hydroxyapatite (HA)/tooth surfaces and low toxicity, and promoted mineralization of PASP, like mineralization protein ( Hou et al, 2020 ). And the reason for antiadhesion is as follows ( Figure 3 ): Firstly, a water layer is formed due to hydrophilicity ( Lüsse and Arnold, 1996 ; Aray et al, 2004 ); in addition, “steric repulsion” can be obtained from the long chain of PASP-PEG, which is an entropic effect concerning the change in free energy associated with confinement and the dehydration of soft polymer chains ( Hui et al, 2017 ).…”