Permanent tooth eruption is the process of replacing primary teeth (deciduous teeth) with permanent teeth (adult teeth). Permanent tooth eruption starts at the age of 6 years; usually, molars are the first permanent teeth to erupt into the oral cavity.
Stages of tooth eruption
Tooth eruption consists of three stages:
- Pre-eruptive: During this stage, tooth buds move constantly in the jaws to position themselves for eruptive movement. The pre-eruptive stage begins at the end of tooth development and ends at the beginning of root formation.
- Eruptive: In this stage, the teeth move from their developmental site into their functional position in the oral cavity.
- Post-eruptive: It is the final stage that maintains the position of the tooth in occlusion by compensating jaw growth. It starts when the teeth attain occlusion and continues until the tooth remains in the oral cavity.
Sequence of permanent tooth eruption
| Type of teeth | Upper teeth | Lower teeth |
|---|---|---|
| First molars | 6-7 years | 6-7 years |
| Central incisors | 7-8 years | 6-7 years |
| Lateral incisors | 8-9 years | 7-8 years |
| Canine teeth | 11-12 years | 9-10 years |
| Premolars | 11-12 years | 10-12 years |
| Second molars | 12-13 years | 11-13 years |
Primary teeth Vs permanent teeth
Children develop their first tooth around 6–7 months, and a total of 20 primary teeth erupt by the age of 3 years. Primary teeth help the child chew properly and develop correct speech. Four new baby teeth can be seen every 6 months in children.
A set of 32 permanent teeth, which are replaced by primary teeth, can be seen over the years. Adult teeth are larger in size and volume than primary teeth. Oral hygiene and care must be practiced on primary teeth for the ideal eruption of permanent teeth.
