Human tooth development inner enamel epithelium) What follows is part of the initial 'enamel organ', the center of which is made up of stellate reticulum cells that serve to protect the enamel organ. This is all encased by the OEE layer. Other events occur during the bell stage. The dental lamina disintegrates, leaving the developing teeth completely separated from the epithelium of the oral cavity; the two will not join again until the final eruption of the tooth into the mouth. The crown of the tooth, which is influenced by the shape of the inner enamel epithelium, also takes shape during this stage.
Tooth whitening filling the root canal with gutta-percha points, cleaning the inside of the canal using etchant and placing a peroxide gel or sodium perborate tetrahydrate into the pulp chamber so they can work directly inside the tooth on the dentine layer. In this variation of whitening the whitening agent is sealed within the tooth over a period of some days and replaced as needed, the so-called "walking bleach" technique.. A seal should be placed over the root filling material to minimise microleakage. There is a small risk of external resorption. An alternative to the walking bleach procedure is the inside-out bleach