Abstract
Transposition of teeth has been observed and reported in the past.
In most of these cases, the treatment of transposition of the teeth begins at Hellman's dental stage III B.
In this case, we found them at Hellman's dental stage III A and conducted for a long term investigation.
Causes of transposition of the teeth seemed to be the malposition and the wrong direction of the canine and the first premolor.
The following had to be considered in the treatment of this case.
1. At, the early stage of Hellman's dental stage III A, we recognized transposition of the teeth and put this under observation for a long period of time. We then made best choice of starting the treatment.
2. We needed to maintain the eruption space in order to promote the natural eruption of the transposition of the teeth.
3. We needed to know the root formation, position, direction and existance of impediment factors (such as odontoma) to diagnosis the natural eruption of the transposition of the teeth, so using 3 DCT was very useful.
4. At Hellman's dental stage III B, we decided the order of tooth arrangement, and it was then possible to shorten the treatment period.
