DOH114 Lecture Notes - Lecture 12: Permanent Teeth, The Roots
PRIMARY DENTITION
Eruption starts 6mo: Incisors → 1st → canines → 2nd (mandibular → maxillary)
Key differences
1. Smaller in overall size and crown dimensions.
2. Have markedly more prominent cervical ridges
3. Are narrower at their “necks”
4. Are lighter in colour
5. Have roots that are more widely flared
6. Molars have narrower buccolingual diameters
More specific
1. The crowns of primary anterior teeth are wider mesiodistally in comparison
with their crown length than are the permanent teeth.
2. The roots of primary anterior teeth are narrower and longer comparatively
3. Narrow roots with wide crowns present an arrangement at the cervical third
of crown and root that differs markedly from that of the permanent anteriors
4. The roots of the primary molars accordingly are longer and more slender
and flare more, extending out beyond projected outlines of the crowns.
This flare allows more room between the roots for the development of
permanent tooth crowns
5. The cervical ridges of enamel of the anterior teeth are more prominent.
These bulges must be considered seriously when they are involved in any
operative procedure.
6. The crowns and roots of primary molars at their cervical portions are more
slender mesiodistally.
7. The cervical ridges buccally on the primary molars are much more
pronounced, especially on the maxillary and mandibular first molars.
8. The buccal and lingual surfaces of primary molars are flatter above the
cervical curvatures than those of permanent molars; this narrows the
occlusal surfaces.
