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This issue features articles on e-cigarettes, peri-implantitis, and ceramic dental implants.
Cover image: Human tooth fractured enamel. SEM of a fracture in a tooth revealing the enamel rod morphology. Tooth enamel is the highly mineralised covering of the crown of a tooth. It is the hardest and most highly mineralised substance of the body. Ninety-six percent of enamel consists of mineral, with water and organic material composing the rest. Enamel is a translucent substance composed of parallel rods (or prisms) of highly calcified material cemented together by a hard, calcified substance. The basic unit of enamel is called an enamel rod or enamel prism which is a tightly packed mass of hydroxyapatite crystals in an organised pattern. The rods are arranged perpendicular to the surface of the enamel. Hydroxylapatite is a crystalline calcium phosphate. Enamel has two unique classes of proteins called amelogenins and enamelins. Magnification: x400.