Development and Pre-Clinical Evaluations of a Novel Dentine Substitute

A new material in the field of restorative dentistry has to combine physical and biological properties with sealing capacity and handling properties. It's a long way from the characterization of the material and the setting reaction to the clinical trials but it's also a beautiful challenge to improve and to evaluate a new material in the same time. Most of the behaviour and of the physical properties of tri calcium silicate cements could be explained from the scientific literature of concrete and from the understanding of the different speciations of water inside the cement: adsorbed, inter-layer or linked. Then, the characterization of the setting process can easily be evaluated by the evolution of the different mechanical properties such as microhardness, flexural strength, compressive strength. However, the understanding of the behaviour of the interface with dental tissues needs other methodologies such as impedance spectroscopy, dye penetration measurements, SEM observations. The main interest of this kind of dentin substitute is the crystallization of a “hydroxyapatite like” material inside the dentine tubules without any kind of dentin conditioning. It's there the opportunity to seal the interface and to improve the quality of sealing with time while many other materials are decreasing regarding this property. We called these crystals “mineral tags” because of the structure and of the localization of these new formations. Obviously, we are now going to evaluate with more sophisticated devices the interface between dentine and calcium silicate cements to demonstrate the potential of such material in term of bioactivity.