936H
Fig. 14.15 A 9-year-old child with an anterior open bite associated with thumb
sucking. (b) A 16-year-old girl with a continuing digit-sucking habit causing a
localized open bite.
937H
Fig. 14.16 (a) A 12-year-old girl whose digit-sucking habit has caused an anterior
open bite and increased overjet. (b) and (c) Split plate with a steep anterior bite plane
to break the habit while the overjet is being reduced.
14.4.6 Incisor spacing⎯mid-line diastema
This is mentioned only to point out that treatment just for spacing is rarely indicated
in the mixed dentition stage. Parents are often concerned about spacing of the upper
incisors, and they can be reassured that it will often reduce as the permanent upper
canines erupt. It is, however, important to ensure that an upper mid-line diastema is
not due to a supernumerary tooth (see 938HSection 14.6.1). A diastema may also be due to
generalized spacing, diminutive teeth, congenital absence of upper lateral incisors, or
to a fleshy upper labial frenum. There is some disagreement about the role of
frenectomy in the treatment of diastemata, but it is very rarely indicated in the mixed
dentition stage and is probably best carried out during active orthodontic treatment.