951H
Fig. 14.20 (a) The panoramic view shows that the crown of the |3 is close to the mid-
line. (b) The lateral view shows that it is palatal to the roots of the incisors.
14.5.4 Early treatment
During the later mixed dentition, if an upper canine is not palpable normally and is
found to be ectopic, extraction of the primary canine has a good chance of correcting
or improving the path of eruption of the permanent canine, provided it is not too
severely displaced. Extraction of the primary canine is only appropriate under these
conditions:
(1) early detection⎯mixed dentition;
(2) canine crown overlap of no more than half the width of the adjacent incisor root as
seen on a panoramic view;
(3) canine crown no higher than the apex of the adjacent incisor root;
(4) angle of 30° or less between the canine's long axis and the mid-sagittal plane;
(5) reasonable space available in the arch⎯no more than moderate crowding.
Unless the upper arch is spaced, the contralateral primary canine should also be
removed to prevent the upper centreline shifting. Eruption of the permanent canine
should be monitored clinically and if necessary radiographically, and specialist advice
sought if it fails to show reasonable improvement after a year.
The main disadvantage of extracting the primary canine is losing the option of
retaining it if the permanent canine fails to erupt. It may also allow forward drift of
the upper buccal teeth where there is a tendency to crowding, and if space is critical a
space maintainer should be fitted.
14.5.5 Later treatment
The treatment options in the permanent dentition are to:
(1) expose the canine and align it orthodontically;
(2) transplant the canine;
(3) extract the canine;