Spacing – detailed

➤ Lower lip trap

A lower lip trap can cause the upper incisors to be proclined and spacing to develop.

➤ Ectopic or impacted teeth

Ectopic or impacted teeth are not in their normal arch position, hence sometimes causing spacing to arise. It may also displace teeth which it impacts with, causing a diastema (i.e. impacted maxillary canines may displace the upper lateral incisors).

➤ Missing teeth or hypodontia

Multiple missing teeth is an indication for future spacing issues. This should be assessed and sometimes managed with the patient and parent at a younger age.

➤ Aesthetic concerns of spaces

Generalised or localised spacing in the permanent dentition can be an aesthetic concern to the patient and is an indication for treatment (Wong et al. 2006). The severity of the problem may not always be associated with the psychological concern to the patient (Jolley et al. 2010, Meyer-Marcotty et al. 2010).

➤ Missing teeth or hypodontia

• Besides third molars (25%), the second premolars (3%), upper lateral incisors (2%) and lower incisors (< 1%) are the more common teeth to suffer from agenesis (Wisth et al. 1974, Graber 1978)
• Prevalence of hypodontia (two or more teeth missing, excluding third molars) is 6.4% and a higher prevalence in Africa at 13.4% (Khalaf et al. 2014).
• Sometimes second premolars develop late and the contralateral side should be used as a guide.
• Hypodontia is closely associated with microdontia and ectopic canines (Graber 1978, Peck et al. 1996).
• Early loss of permanent teeth due to pathologies and extractions are also another cause for localised spacing.

➤ Frenum associated with spacing

Central diastemas are common expressions of localised spacing in the dentition. Most often there would be closely involved frenum that could be preventing the incisors from contacting.

➤ Hypoplasia or dimunitive teeth

Generalised spacing can be associated with a primary tooth-jaw size discrepancy. Teeth may be relatively small compared to the jaw size and this can be seen with microdontia patients (Graber 1978)

➤ Ectopic or impacted teeth

Ectopic or impacted teeth outside the arch form can lead to localised spacing (e.g. palatally impacted canines). The arch may however be considered crowded when bringing the tooth into the arch form. (Peck et al. 1996)