The first four teeth to erupt in the primary dentition located between the maxillary and mandibular canines. They are morphologically similar to their permanent successors; however, although smaller, their mesio-distal width is relatively larger when compared to the vertical height (axial length) of the crown to give them a more bulbous appearance. Unlike the permanent incisors, they do not have any tubercles (mamelons) on the incisal edge on eruption. Relative to the size of the tooth, the pulp chamber is larger than in the permanent incisors and therefore the surrounding dentine is proportionally thinner. Calcification of the primary incisors commences at 4–5 months in foetal life and the crowns are normally complete by 2 months after birth. They erupt at about 6–8 months after birth and the roots are complete at 1–2 years. See also dentition.
Primary (deciduous) incisors