These are the first teeth to erupt into the oral cavity. The primary dentition is comprised of 20 teeth. Often these teeth are referred to as deciduous teeth. These teeth will be exfoliated (lost) as the permanent teeth erupt. In each arch of the mouth, there are two central incisors, two lateral incisors, two canines, and four molars. The teeth are usually recognized by a letter of the alphabet beginning with “A” (Maxillary right second molar) and ending with “T” (Mandibular right second molar). There are no premolars or third molars in the primary dentition. The approximate eruption and exfoliation dates for the primary teeth are listed in Table 1.
Table 1. Primary Dentition.2
|Central Incisor||8-12 Months||6-7 Years|
|Lateral Incisor||9-13 Months||7-8 Years|
|Canine||16-22 Months||10-12 Years|
|1st Molar||13-19 Months||9-11 Years|
|2nd Molar||25-33 Months||10-12 Years|
|Central Incisor||6-10 Months||6-7 Years|
|Lateral Incisor||10-16 Months||7-8 Years|
|Canine||17-23 Months||9-12 Years|
|1st Molar||14-18 Months||9-11 Years|
|2nd Molar||22-31 Months||10-12 Years|
Figure 7. Primary Dentition Teeth Named and Numbered.