Hygiene Atlas

Atlas · Plate III · Histology and Embryology · 02

Tooth development

Teeth begin forming around the sixth to seventh week in utero and pass through initiation, bud, cap, bell, apposition and maturation. The enamel organ makes enamel, the dental papilla becomes dentin and pulp, and the dental follicle becomes cementum, PDL and bone. Hertwig's epithelial root sheath shapes the root, and its leftover rests of Malassez can later form cysts.

High-yield facts · 7

  1. Teeth arise from ectoderm (enamel) and neural crest-derived ectomesenchyme (dentin, pulp, cementum, PDL).S52
  2. Primary tooth development begins around the 6th-7th week in utero with the dental lamina.S52
  3. Stages: initiation, bud, cap, bell, apposition, maturation.S52
  4. Enamel organ, dental papilla and dental sac (follicle) form at the cap stage; papilla becomes dentin and pulp, follicle becomes cementum, PDL and alveolar bone.S52
  5. Reciprocal (inductive) interaction: preodontoblasts differentiate into odontoblasts, which lay down the first dentin; that dentin then triggers ameloblasts to make enamel.S52
  6. Hertwig epithelial root sheath determines root number and shape; its rests are the epithelial rests of Malassez.S52
  7. Crown formation of first permanent molars begins at about birth.S52

Facts are written in our own words; each tag links to its source. Values marked "sources vary" differ between references, so check the one your program uses.