This study was performed to compare the bone mineral densities measured at mandibular premolar area by copper-equivalent image and hydroxyapatite phantom with those measured at radius by dual energy absorptiometry and to evaluate the clinical usefulness of Digital system with slide scanner, copper-equivalent image, and hydroxyapatite phantom. For experiment, intraoral radiograms of 15 normal subjects ranged from 20 years old to 67 old were taken with copper-step wedge at mandibular premolar area and bone mineral densities calculated by conversion equation to bone mineral density of hydroxyapatite were compared with those measured at radius distal 1/3 area by Hologic QDR-1000. Obtained results as follows: 1) The conversion equation was Y=5.97X-0.25 and its determination coefficient was 0.9967. The coefficient of variation in the measurement of copper-equivalent value ranged from 4% to 8% and showed high reproducibility. 2) The coefficient of variation in the measurement of bone mineral density by the equation ranged from 7% to 8% and showed high reproducibility. 3) The bone mineral densities ranged from 0.35 to 0.79g/cm2 at mandibular premolar area. 4) The correlation coefficient between bone mineral densities at mandibular premolar area and those at radius distal 1/3 area was 0.8965. As summary, digital image analyzing system using copper-equivalent image and hydroxyapatite phantom appeared to be clinically useful to measure the bone mineral density at dental area.
Bicuspid ; Bone Density* ; Durapatite ; Humans ; Mandible* ; Radius ; Young Adult

Traumatic bone cyst is a pathologic cavity that is not lined with epithelium. It is, therefore, not a true cyst. It may be a normal variant rather than a disease process. The etiology of the condition is unknown. This condition is occured widely ranging ages(2 to 75years), however, most are found during the second decade of life. Radiographically, this condition is radiolucent lesion with well-defined outline, scalloping of superior margins. Cyst enucleation and curettage is the treatment of choice. The authors compared and analyzed the clinicoradiologic features of the five cases of traumatic bone cyst, diagnosed at the Dental college hospital in Chosun University, Kwangju, Korea. The five cases were shown the follwed results; 1. 3cases occured in second decade of life and no significant sex differences (M:F, 2:3) All cases occurred in mandible. 2. Two patients complained symptoms, but three cases had no symptom with encountering during routine examination. 3. In 3 of 5cases, teeth vitality existed except one tooth and no checking of teeth vitality in two cases. 4. All cases didn't have any accurate trauma history, but one case was in orthodontic treatment, another case was postextraction site area. 5. Radiologically, "scalloping appearance" were evident in all cases; in 3 cases, multilocular tendency and only one case seen intact mandibular canal image. 6. Histologically, alll section showed bone trabeculae with blastic activity, 2 cases showed no epithelial lining, and other 2 cases were seen innflammatory cell infiltration in edematous tissue. 7. Surgical intervention (curettage) was that treatment of choice.
Bone Cysts* ; Curettage ; Epithelium ; Gwangju ; Humans ; Korea ; Mandible ; Pectinidae ; Sex Characteristics ; Tooth