A median diastema is the space found between the central incisors (most commonly uppers). It is also commonly known as a midline diastema.

Potential Causes Of Median Diastema:

  • Small teeth in a large arch
  • Upper arch spacing
  • Missing or diminutive lateral incisors
  • Midline supernumerary
  • Digit sucking
  • Low lying frenal attachment prevents central incisors moving together (rare)- shown by blanching of the incisive papilla on stretching the frenum and notching between the upper 1’s.
  • Developmental ‘ugly duckling stage’– caused by the lateral incisors applying pressure to the central incisor roots- tends to resolve overtime after the upper 3’s erupt.

Management Of Median Diastema

  • Prior to the eruption of the upper canines (age 11-12), leave and monitor and explain to the parent the diastema may resolve following the eruption of the upper canines
    • Only intervene prior to the eruption of the permanent canines if the diastema is >3mm and there is insufficient space for the eruption of the lateral incisors.
  • Take a periapical of the upper anterior teeth to assess for a supernumerary tooth, followed by extraction.
  • If the median diastema remains following eruption of the permanent canines either:
    • Accept the space
    • Composite build up
    • Close with a fixed appliance
  • Consider frenectomy if the median diastema is caused by a low lying frenum.
References
  1. Littlewood, S.J. and Mitchell, L., 2019. An introduction to orthodontics. Oxford university press.
  2. Abrahams, R. and Kamath, G., 2014. Midline diastema and its aetiology–a review. Dental update, 41(5), pp.457-464.
  3. Savarrio, L. and McIntyre, G.T., 2005. To open or to close space–that is the missing lateral incisor question. Dental Update, 32(1), pp.16-25.
  4. Soo, T.C., 1985. Median diastema closure. Dental update, 12(2), p.121.

See also Impacted Canines