Description

• Teething is the eruption of the primary or deciduous teeth, which most children experience without difficulty. It is a natural, gradual, and predictable process, with normal variation among infants.
• Primary (deciduous) teeth:
  • Primary tooth eruption usually begins at 5–7 months of age.
  • The order of primary tooth eruption and average age is:
    • Central mandibular incisors (5–7 months)
    • Central maxillary incisors (6–8 months)
    • Lateral mandibular incisors (7–10 months)
    • Lateral maxillary incisors (8–11 months)
    • Cuspids (16–20 months)
    • 1st molars (10–16 months)
    • 2nd molars (20–30 months)
  • Delayed eruption may be familial or due to systemic syndromes or nutritional deficiencies. Delayed eruption may also be seen with cleft palate (1) and lower birth weight (2,3).
  • Tooth eruption in premature infants occurs according to postconceptual age rather than age since birth (chronological age).
  • Natal/Neonatal teeth:
    • Natal teeth (present at birth) occur in 1/2,000 neonates.
    • Neonatal teeth erupt in the 1st month of life.
    • Natal/Neonatal teeth are most often prematurely erupted primary (deciduous) teeth, but may be supernumerary.
    • 15–20% of cases are familial; also may be secondary to a syndrome or congenital anomalies of the head and neck.
    • Natal/Neonatal teeth may be loose, but most are the normal deciduous lower central incisors and can persist.
    • Natal/Neonatal teeth may be removed if there is an aspiration risk or if they cause trauma to the infant or to the mother (breastfeeding).
• System(s) affected: Gastrointestinal

Epidemiology

Incidence
Predominant age: Birth–3 years of age

Risk Factors

Genetics
Both premature and delayed tooth eruption may be familial. Primary failure of eruption has been linked to mutations of the PTHR1 gene (4).

Etiology

Teething symptoms are more common with eruption of the primary incisors (5)[B].

Commonly Associated Conditions

Teething may be coincident with other conditions, such as common childhood illnesses (e.g., roseola, viral gastroenteritis, upper respiratory infection) and serious bacterial infections, causing local or systemic signs and symptoms (e.g., fever, GI disturbance, fussiness, drooling, rash, and sleep disturbance).