Tooth polishing This outermost fluoride rich layer of enamel is removed when tooth polishing is provided. The mineral components of saliva and polishing pastes containing fluoride can assist in remineralizing this outer layer. The enamel surface is strong enough to withstand repeated tooth polishing, but it should be avoided on newly erupted teeth, exposed root surfaces and areas of demineralization. If polishing does occur on these surfaces, fluoride therapy can minimize the risk of dental caries. Excessive pressure can lead to frictional heat that may cause pulpal discomfort or necrosis of the dental pulp. Surfaces of restorations may be damaged by conventional
Eggshell the uterus. The egg can take up fluids and grow in size during this process, and the final, most rigid layer is not added until the egg is full-size. Hatching birds, amphibian and egg-laying reptiles have an egg-tooth used to start an exit hole in the hard eggshell. Eggshell waste is fundamentally composed of calcium carbonate, and has the potential to be used as raw material in the production of lime. Eggshell An eggshell is the outer covering of a hard-shelled egg and of some forms of eggs with soft outer coats. Insects and other arthropods lay a variety of