歯および顎骨における実質欠損の検出に関する実験的研究 : デンタル X 線撮影とパノラマ X 線撮影による検出能の比較

抄録

Comparison of panoramic and periapical radiography in the detection of artificial defects in the teeth and jaws was carried out in this study. The artificial defects were made on the proximal surfaces of the teeth and into the cortical plate, at the root apex of the dry skulls, with cylindrical burs. Results obtained were as follows : 1. Defects with a size of 1 mm were detected on the mesial proximal surfaces of the maxillary and mandibular central incisors by both techniques. However, on the distal proximal surfaces of the maxillary and mandibular molar and premolars, defects with a size of 2 mm were not detected by either techniques. In panoramic radiography, especially, image overlap made the shadow of the interproximal tooth surfaces difficult to see. When the defects in the proximal surfaces of the maxillary and mandibular molars and premolars were enlarged to 3 mm, the defects were detected by both techniques. 2. Defects with a size of 2 mm in the palatal and lingual cortical plates at the maxillary and mandibular first premolars were detected by both techniques. However, in the palatal cortical plate at the maxillary central incisor and the first molar and in the lingual cortical plate at the mandibular first molar, defects with a size of 2 mm were not detected by both techniques. A defect with a size of 2 mm in the lingual cortical plate at the mandibular central incisor was detected by periapical radiography, but not detected by panoramic radiography. When the defects in the palatal and lingual cortical plate of the maxilla and mandible were enlarged up to 3 mm, the defects, except that in the maxillary first molar, were detected by both techniques. The defect with a size of 3 mm in the palatal cortical plate at the maxillary first molar was not detected by panoramic radiography, but detected by periapical radiography. When the defect in the palatal cortical plate at the maxillary first molar was enlarged up to 5 mm, the defect was detected by panoramic radiography. 3. Defects with a size of 2 mm in the buccal cortical plate at the maxillary and mandibular molar and premoalrs were detected by both techniques. The defects with a size of 2 mm in the buccal cortical plate at the maxillary and mandibular central incisors were not detected by either technique. However, when the defects in the buccal cortical plate at the maxillary and mandibular central incisors were enlarged up to 3 mm, the defects were detected by both techniques. From the above results it was found that panoramic radiography is almost equal to periapical radiography in the detection of defects in the teeth and jaws. Therefore, panoramic radiography should be used clinically as a supplement to periapical radiography for obtaining more accurate diagnosis of jaw lesions.