At what age do primary and permanent teeth erupt?

From the Guidelines

Primary teeth typically erupt between 4-10 months of age, while permanent teeth begin to erupt around age 6. The eruption of teeth is a complex process influenced by genetic factors, nutrition, and overall health, leading to significant variation in the timing among individuals 1.

Key Points to Consider

• The first primary teeth to appear are usually the lower central incisors, with most children having a complete set of 20 primary teeth by age 3.
• Permanent teeth start erupting around age 6, with the first molars and lower central incisors being among the first to appear.
• The eruption process continues until approximately age 21, when the third molars (wisdom teeth) may emerge.
• The timing of tooth eruption is controlled by a complex interaction of genetic factors and growth hormones that regulate the development and movement of teeth from their formation sites within the jawbones to their functional positions in the mouth.

Clinical Implications

• Understanding the typical timeline for tooth eruption is crucial for anticipatory guidance in infant oral health, allowing for early identification and intervention in cases of delayed or premature eruption.
• The American Academy of Pediatric Dentistry recommends the first oral examination to occur within six months of the eruption of the first primary tooth but by no later than 12 months of age, highlighting the importance of early dental care 1.
• Variations in tooth eruption timing should be considered in the context of overall health and development, with significant deviations potentially indicating underlying issues that require medical or dental evaluation.

From the Research

Primary Teeth Eruption

• The median ages of eruption for primary teeth are:
  • 7.1 months (male) and 7.6 months (female) for mandibular primary central incisors 2
  • 8.7 months (male) and 9.2 months (female) for maxillary primary central incisors 2
  • 10.0 months (male) and 10.3 months (female) for maxillary primary lateral incisors 2
  • 10.4 months (male) and 10.8 months (female) for mandibular primary lateral incisors 2
• The age of the first primary tooth eruption is between 2-15 months old, with a median age of 8 months old 3
• The first primary tooth eruption is typically the incisor of the mandible in 95.3% of infants 3

Permanent Teeth Eruption

• The eruption time of the first permanent tooth is correlated with the eruption time of the first primary tooth, with a delay or early eruption of the first primary tooth resulting in a corresponding delay or early eruption of the first permanent tooth 4
• The exact age of permanent teeth eruption is not specified in the provided studies, but it is known that permanent teeth typically begin erupting around the age of 6 years old, with the first permanent teeth being the first molars and the lower central incisors

General Trends

• Teething typically begins at around 6 months of age and continues until the child is about 3 years old 5
• The median age of total teeth emergence is 31 months of age 3
• There is a positive correlation between the time of first tooth eruption and the time of total teeth emergence 3