Visibility of the mandibular canal and the mental foramen in panoramic radiography / 대한구강악안면방사선학회지

PURPOSE: To determine the head position that the superior border of the mandibular canal as well as mental foramen can be more clearly visualized in panoramic radiography MATERIALS AND METHODS: Ten dry mandibles were radiographed bilaterally using PM 2002 CC panoramic machine. A 20 mm thick aluminium filter was added to the slit collimator to obtain radiographs with acceptable density. The specimens were tilted by 2, 4, 6, 8, and 10 degrees downward with and without radiopaque markers. Radiopaque markers were inserted into the mandibular canals and the mental canals of each side of the specimens to serve as reference image when assessing the radiographs. The visibility of the mandibular canal and the mental foramen was estimated by 4 observers on all radiographs. The obtained results were analyzed statistically. RESULTS: Mandibular canals were significantly more clearly visible in the radiographs with 4 and 6 degree downward position on both sides (P<0.05). Mental foramens were significantly more clearly visible in the radiographs with 4, 6, and 8 degree downward on right side and 6 degree downward on left side (P<0.05). There was not significant difference between right and left sides. CONCLUSION: Panoramic radiographs with 4 to 6 degree downward tilting could be valuable in locating the mandibular canal as well as the mental foramen.

Cleidocranial Dysplasia: Report of a Case / 대한구강악안면방사선학회지

Cleidocranial dysplasia(previously known as cleidocranial dysostosis) is a well-known, rare and hereditary skeletal disorder characterized by a variety of dental abnormalities and as its name implies, striking involvement of the cranial vaults and clavicles. A 17-year-old female who presented with short stature and prolonged retention of deciduous teeth, subsequent delay in eruption of permanent teeth is described. She could touch her shoulders together at the midline anteriorly. Diagnostic procedures showed hypoplasia of the maxillary and zygomatic bones, open fontanelles and sutures, and aplasia of the clavicles. The paranasal sinuses were absent or underdeveloped. Characteristically, she had near parallel-sided borders in the ascending ramus of the mandible and abnormal-shaped, the slender pointed coronoid process. The zygomatic arches had a downward bend and discontinuity at the zygomaticotemporal suture area. Radiographic and clinical investigations of her cranial and skeletal abnormalities revealed features of cleidocranial dysplasia.