Human tooth development the formation of odontoblasts continue from the tips of the cusps, the odontoblasts secrete a substance, an organic matrix, into their immediate surrounding. The organic matrix contains the material needed for dentin formation. As odontoblasts deposit organic matrix termed predentin, they migrate toward the center of the dental papilla. Thus, unlike enamel, dentin starts forming in the surface closest to the outside of the tooth and proceeds inward. Cytoplasmic extensions are left behind as the odontoblasts move inward. The unique, tubular microscopic appearance of dentin is a result of the formation of dentin around these extensions. After dentin formation begins,
Layer by Layer there are many variant techniques for the final layer, depending on whether the corner or edge pieces are solved first. The CFOP speedcubing technique, developed by Jessica Fridrich and others in the 1980s, similarly divides the puzzle into layers to be solved. However the method uses far more algorithms and shortcuts than the beginners' methods. Layer by Layer The Layer by Layer method is a method of solving the 3x3x3 Rubik's Cube. Many beginners' methods use this approach, but it also forms the basis of the CFOP speedcubing technique. The Layer by Layer Method was pioneered by David Singmaster in