Human tooth development focused on determining the processes that initiate tooth development. It is widely accepted that there is a factor within the tissues of the first pharyngeal arch that is necessary for the development of teeth. The tooth germ is an aggregation of cells that eventually forms a tooth. These cells are derived from the ectoderm of the first pharyngeal arch and the ectomesenchyme of the neural crest. The tooth germ is organized into three parts: the enamel organ, the dental papilla and the dental sac or follicle. The "enamel organ " is composed of the outer enamel epithelium, inner enamel epithelium,
Tooth decay rarely does caries affect the cementum alone. Roots have a very thin layer of cementum over a large layer of dentin, and thus most caries affecting cementum also affects dentin. In the Western world, the primary approach to dental hygiene care consists of tooth-brushing and flossing. The purpose of oral hygiene is to remove and prevent the formation of plaque or dental biofilm. While evidence that flossing prevents tooth decay is limited, the practice is still generally recommended. As the amount of bacterial plaque increases, the tooth is more vulnerable to dental caries when carbohydrates in the food are left