There
are many forms of orthodontic appliances depending on the type
of problem and operator preference. The following treatments are
what I have found work well, however there are many other acceptable
methods for most of these problems.
Anterior
crossbite is usually corrected by the use of a maxillary
expander. This is at minimum a three-stage procedure. During
the first visit the patient is evaluated and sedated. Whole mouth
impressions are taken, and sent to the orthodontic laboratory
for fabrication of the appliance. The second visit is for cementation
of the appliance and instructing the owner on how to adjust the
appliance. The owner adjusts the appliance until the teeth are
in the correct position. Then the appliance is left in place
for a period of time as a retainer. This is usually not long
in these cases as the overlapping of the teeth can act as a natural
retainer. Then the patient is sedated and the appliance is removed
and the teeth cleaned. Arch bars and elastic ligatures or incline
planes can be used as well with good success.
Mesial
tipped upper canines (Lance effect) is usually treated by
means of elastic bands. The patient is sedated and orthodontic
brackets are attached to the canine as well as posterior teeth
(to act as an anchor for movement). Often several teeth are included
in the anchorage, or possibly wires in the maxillary bone, or
possibly extraoral anchors (headgear). Orthodontic elastics are
stretched between the teeth to stimulate movement. The elastics
are change by the owner usually without sedation. When the tooth
is in the correct position, the retention period ensues to avoid
the tooth moving back to its original position.
Base
narrow canines are orthodontically treated by means of an
incline plane. This works by making a base over the palate between
the upper canines and forward to the upper incisors, and then
creating a groove starting at where the offending tooth or teeth
strike the palate, and directing the teeth to the correct place
in the mouth. The force is applied when the animal closes his
mouth. This appliance can be created in the animal's mouth or
on models by a dental lab. The advantages to creating the appliance
in the mouth are that it is done in one anesthetic procedure
and is slightly less expensive. The advantages to the laboratory-fabricated
appliance are that there is less irritation to the palate, and
that the appliance can be made to expand to allow the patient
to grow. When the tooth is in the right position the appliance
is removed and the palate acts as a natural retainer. An expansion
device can be made to fit between the lower canines to push them
out as well.
Posterior
crossbite and rotated teeth are
very difficult to treat orthodontically and therefore will not
be covered on this page.