Alban Desoutter

1 Introduction The dentin–enamel junction (DEJ) is one of the key structures of the human tooth. It is in this transition zone that highly mineralized enamel is joined to dentin, which is rich in organic matrix. Enamel is composed primarily of a mineral phase (96%) with a small amount of water (3%) and a residue of organic matter (1%). It is the hardest element in the human body.

2. Materials and Methods 2.1. Porous Silicon Particle Production Porous silicon (pSi) wafer/chips were prepared via electrochemical etching of silicon wafers (p++ type boron-doped crystalline, 0.0012 Ωcm resistivity) in a custom-made Teflon cell. First, etching was performed at a constant current density of 200 mA/cm2 for 25–30 min from generator source, in a hydrofluoric acid (HF) solution in ethanol (3:1 HF: ethanol solution, v/v) which formed a porous layer on the surface.