Page 115 - REMOVABLE ORTHODONTIC APPLIANCES

Chapter 12

Problem cases

This chapter deals with a number of situations, mesially with a removable appliance - so bring-
many of which will demand fixed appliances if ing them into contact with the central incisors.
satisfactory results are to be achieved. In
certain situations, however, judiciously planned
extractions and the use of removable appli- Peg-shaped upper lateral incisors
ances may produce worthwhile improvements.
These have an unattractive appearance and can
be difficult to restore satisfactorily. Attempts to
move the posterior teeth forward to close space
Missing teeth and teeth with may result in an unsatisfactory buccal intercus-
abnormal form pation. Where there is sufficient crowding,
extraction of peg-shaped lateral incisors may be
considered, but removable appliances are only
Missing upper laterals
suited to deal with this problem when the
Absence of an upper lateral incisor may be canines are distally inclined and can be tipped
suspected when the deciduous tooth is absent into contact with the centrals.
or if its loss is delayed. If the permanent tooth
does not erupt, radiographic investigation is
required. Missing lower incisors
Where both upper laterals are congenitally Lower central incisors are occasionally absent,
absent and there is a degree of crowding, inter- with the deciduous incisors being retained. In
ceptive extraction of the upper deciduous later- the absence of marked crowding it is usually
als and deciduous canines may encourage advisable to retain the deciduous incisors until
forward eruption of the permanent canines, so such time as they can be satisfactorily restored
allowing them to make contact with the central or replaced. Where crowding is present it is
incisors. Where only one of the lateral incisors sometimes possible to extract the deciduous
is missing, a less satisfactory result is likely to be incisors and later the deciduous canines to
obtained. The possibility of a centre-line shift encourage forward movement of the lovvcr
may make it preferable to plan treatment buccal segments and assist space closure.
involving prosthetic replacement of the missing
lateral incisor at a later stage. An older patient
with a missing lateral incisor will usually require
fixed appliances. In the presence of crowding Missing second premolars
and distally inclined canines, however, it may Second premolars are commonly congenitally
occasionally be possible to tilt the canines absent. This may be detected as part of a