Development
For more information on general tooth development, see Tooth development.The aggregate of cells which eventually form a tooth are derived from the ectoderm of the first branchial arch and the ectomesenchyme of the neural crest. As in all cases of tooth development, the first hard tissue to begin forming is dentin, with enamel appearing immediately afterwards.
The deciduous maxillary central incisor begins to undergo mineralization 14 weeks in utero, and at birth 5/6ths of the enamel is formed. The crown of the tooth is completed 1.5 months after birth and erupts into the mouth at around 10 months of age, making these teeth usually the second type of teeth to appear. The root completes its formation when the child is 1.5 years old.
The permanent maxillary central incisor begins to undergo mineralization when a child is 3–4 months of age. The crown of the tooth is completed at around 4–5 years of age and erupts into the mouth at 7–8 years of age. The root completes its formation when the child is 10 years old.
Read more about this topic: Maxillary Central Incisor
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