Abstract
In children, we often encounter cases associated with impacted teeth and the abnormal position of the unerupted permanent teeth. These abnormalities may cause malocclusion or cysts as a result. There has been little study to identify the accurate relationship regarding space between the impacted tooth and other teeth in dentition and the morphology of the involved tooth, all of which is necessary for occlusal guidance and surgical treatment. Three-dimensional assessment was therefore investigated with use of computed tomography (CT).
The material used was a dry skull of a child in which the tooth with curved root was attached on the maxilla. The silicone impression of the dental arch was then taken and the plaster model of the dental arch was made. The plastic sheet on which the 28 reference points were composed with the gutta-percha was prepared on the dental cast.
The computed tomography was then take on the dry skull and was put on the plastic sheet at 1 mm intervals. The total number of images was 26, which were printed as the same size as the actual one.
The data were compared between the image constructed from CT and the three-dimensional measurement on the actual tooth.
The results were as follows:
1. The difference of the three-dimensional length between Orale, the upper left front teeth and the impacted tooth was very small (-0.03∼+1.66mm).
2. Regarding the volume of the impacted tooth, the difference was 27mm3.
3. The reconstructed images was a satisfactory one which could be applied to the clinical use.
