4. 후두과와 유양돌기의 일차상이 거의 동일한 부위에 중첩되어 나타났으며 후두과의이차상만이 그 반대측 후두과의 일차상 위에 유사한 형태로 약간 확대되어 나타났다.
5. 두개저의 정중부위에 위치한 전두동하연, 토이기안, 접골동하연 및 후두골후방부위의 상이 정중선을 중심으로 좌우 대칭적으로 양측에 나타났다.
[영문]
This study was performed to observe the secondary images and to analyse the relationships between the primary and secondary images in panoramic radiograph.
Using the Moritta's Panex-EC panoramic x-ray machine and the human dry skull, the author analysed 17 radiographs which were selected from 65 radiographs of the dry skull that attached the radipgaque materials, and the attached regions of the radiopaque materials were the normal anatomical structures which were important and the selected regions for the evaluation of the secondary images effectively.
The results were as follows;
1. The cervical vertebrae showed three images. The midline image was the most distorted and less clear, and bilateral images were slightly superimposed over the posterior border of the mandibular ramus.
2. In mandible, the secondary image of the posterior border of the ramus was superimposed on the opposite ramus region, and this image was elongated from the anterior border of the ramus to the lateral side of the posterior border of the ramus.
The secondary image of the condyle was observed on the upper area of the coronoid process, the sigmoid notch and the condyle in opposite side.
3. In maxilla, the posterior region of the hard palate showed the secondary image on the lower part of the nasal cavity and the medial wall of the maxillary sinus.
4. The primary images of the occipital condyle and the mastoid process appeared on the same region, and only the secondary image of the occipital condyle was observed symmetrically on the opposite side with similar shape to the primary one.
5. In the cranial base, the anatomical structures of the midsagittal portions like a inferior border of the frontal sinus, sella turcica, inferior borderr of the sphenoid sinus and inferior border of the posterior part of the occipital bone showed the simillar shape between the primary and secondary images symmetrically.