Delay in tooth eruption

Delay in tooth eruption

A delay of up to 12 months maybe less important in a healthy child (1).

Timing of teething varies widely:

• a child's first tooth usually erupts between 4 and 10 months of age, and the full complement of 20 deciduous teeth is almost always present by 30 months
  • thus, on average, roughly one tooth erupts per month between 6 and 30 months of age, closely coinciding with a period during which infants are known to experience frequent minor illnesses and rapid developmental change (2). Average deciduous teething dates include:
    • lower central incisors 5-7 months
    • months upper central incisors 6-8 months
    • upper lateral incisors 9-11 months
    • lower central incisors 10-12 months
    • canines 16-20 months
    • first molars 12-16 months
    • second molars 20-30 months (3)
  • some children (1%) develop their first tooth before the age of four months and another 1% get their first tooth after the age of 12 months (3).
  • in some children teeth are present at birth (natal teeth) or develop during the first month of life (neonatal teeth) (3)

Causes of delay include:

• localised delays - tooth in the path of eruption, insufficient space in the dental arch, or dental infection
• iatrogenic - cytotoxic therapy, radiotherapy?
• uncommon or rare systemic causes
  • Down's syndrome
  • Cleidocranial dysplasia
  • congenital hypopituitarism
  • congenital hypothyroidism (1)
  • infantile rickets
  • Gardener's syndrome (4)

A delay in tooth eruption of up to 12 months may be of little or no importance in an otherwise healthy child (5)

• relays often result from such local factors as a tooth in the path of eruption, insufficient space in the dental arch, or dental infection
  • ectopic positioning and impaction most often affect the third molars, second premolars, and canines, possibly because these are the last teeth to erupt

If a child has not shown any signs of tooth eruption by 18 months of age, then this is considered delayed and warrants further investigation to rule out any potential underlying health or developmental issues.

Reference:

1. Holt R et al. ABC of oral health. Oral health and disease. BMJ. 2000;320(7250):1652-1655
2. Sarrell M et al. Parents' and medical personnel's beliefs about infant teething. Patient Education and Counseling 2005; 57 (1): 122-125
3. Ashley MP. Personal View: It's only teething... A report of the myths and modern approaches to teething. British Dental Journal 2001;1914-8
4. Ashley MP. Personal View: It's only teething... A report of the myths and modern approaches to teething. British Dental Journal 2001;1914 - 8
5. Holt R, Roberts G, Scully C. Oral health and disease. West J Med. 2001 Mar;174(3):199–202.