Caries is the most common disease in the world. Great efforts have been undertaken for prevention and to identify a regenerative treatment solution for dental caries. Self-assembling β-sheet forming peptides have previously shown to form 3-dimensional fiber networks supporting tissue regeneration. In particular, the self-assembling peptide P-4 has shown potential in the treatment and prevention of dental caries. It has previously been shown that application of monomeric P-4 solution to early carious lesions can increase net mineral gain by forming de novo hydroxyapatite crystals. The hypothesis for the mode of action was that monomeric self-assembling peptide P-4 diffuses into the subsurface lesion body and assembles therein into higher order fibrils, facilitating mineralization of the subsurface volume by mimicking the natural biomineralization of the tooth enamel, and it remains within the lesion body as a scaffold built-in by the newly formed hydroxyapatite. The aim of the present study was to investigate the mechanism of action of the self-assembling peptide P-4 supporting mineralization of carious enamel. By various analytical methods, it could be shown that the self-assembling peptide P-4 diffuses into the subsurface lesion, assembles into higher formed aggregates throughout the whole volume of the lesion, and supports nucleation of de novo hydroxyapatite nanocrystals and consequently results in increased mineral density within the subsurface carious lesion. The results showed that the application of self-assembling peptide P-4 can facilitate the subsurface regeneration of the enamel lesion by supporting de novo mineralization in a similar mode of action as has been shown for the natural formation of dental enamel.

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Biomaterials with antimicrobial properties are now commonly used in different clinical specialties including orthopedics, endodontic, and traumatology. As a result, assessing the antimicrobial effect of coatings applied on implants is of critical importance. In this study, we demonstrate that isothermal microcalorimetry (IMC) can be used for monitoring bacterial growth and biofilm formation at the surface of such coatings and for determining their antimicrobial effects. The antibacterial effects of silver doped hydroxyapatite (HA) and calcium hydroxide coatings on Staphylococcus epidermidis were determined with a minimal workload. Using the Gompertz growth model we determined biofilm growth rates close to those values reported in the literature. Furthermore, we were able to estimate the reduction in the bacterial inocula originally applied at the surface of the coatings. Therefore, in addition to monitoring the antimicrobial effect of silver doped HA and calcium hydroxide coatings, we also demonstrate that IMC might be a valuable tool for assessing such antimicrobial properties of implant coatings at a minimal workload.

Tailor made bioceramic scaffolds in combination with the corresponding surface chemistry and biology is of great importance for a successful implantation and rapid osseo-integration. The present study investigates the fabrication of Hydroxyapatite (HA) scaffolds with defined macro porosity by means of powder based 3D-printing. In order to mime natural bone with its elastic collagen structure, the 3D-printed ceramic structures were post-treated by polymeric infiltration. Compressive Strength analysis (CS) confirmed the positive impact of an elastomeric phase on mechanical properties. 3D-printed HA scaffolds in combination with polymer result in biodegradable scaffolds with promising mechanical properties for potential use in regenerative medicine.

Cytotoxicity of amorphous calcium phosphate (ACP) and chitosan lactate (ChOL) multifunctional and hybrid composite coatings on MRC-5 human lung fibroblast cell line is elucidated. ACP/TiO2 and ACP/TiO2/ChOL are deposited onto Ti by novel in situ anodization/anaphoretic process at constant voltage. Cytotoxicity tests showed that there was no significant decrease in the survival of healthy MRC-5 cells eposed to composite samples without chitosan lactate, while there was an increase in the number of viable cells in the sample containing ChOL. The findings show that there is improved cell proliferation, differentiation and cell viability in the ChOL-containing sample, which makes ACP/TiO2/ChOL coating a good candidate for the applications in medicine and stomatology.