<ORIGINAL ARTICLE>Localization of anti-monocyte/macrophage antibody-positive cells in periodontal tissue of rat maxillary molars after orthodontic tooth movement

To examine the localization of monoclonal anti-monocyte/macrophage (ED1) and macrophage (ED2) antibody-positive cells in periodontium, rat maxillary molar teeth were moved by insertion of band materials. The orthodontic tooth movement was elicited for 5 days, and paraffin-embedded maxillary teeth were stained by fluorescent immunocytochemistry and observed using a confocal laser scanning microscope. The localization of ED1-positive mononuclear cells in the experimental teeth was little different from that in the controls. While ED2-positive mononuclear cells were located throughout the periodontium on the distalside of controls, the number of positive cells decreased on the pressure side of the treated teeth. The present study suggested that most of the immunoreactive mononuclear cells on the distal side of controls are macrophages, while the positive cells on the pressure side of the experimental teeth are osteoclast precursors and a small number of macrophages

<ORIGINAL ARTICLE>The effects of sagittal ramus osteotomy for mandibular prognathism on maximum mouth opening and condylar movement

Maximum mouth opening and condylar movement before and more than 6 months after surgery were analyzed in 23 cases of sagittal ramus osteotomy of the mandible for correction of mandibular prognathism. Condylar movement (translation and rotation) did not show postoperatively a significant difference pre-and postoperatively, and then was a tendency to a reduction of maximum mouth opening was found

Evaluation of X-ray doses and their corresponding biological effects on experimental animals in cone-beam micro-CT scans (R-mCT2).

Studies show that the radiation dose received during a micro-CT examination may have adverse effects on living subjects. However, the correlations between the biological effects and the radiation doses have never been thoroughly evaluated in the majority of cases. In this study, we evaluated the biological radiation effects of measured radiation doses in ICR mice using cone-beam micro-CT scans. Long-term in vivo whole-body micro-CT scans of ICR mice were performed for a duration of 4 weeks. Although a scanning frequency of three scans per week is higher than that necessary for conventional studies, this study represents particular cases where the subjects may undergo an extreme number of examinations. The average X-ray dose of a CT scan measures 16.19 mGy at the center of a phantom and 16.24 mGy at an offset position of 7.5 mm from the center of the phantom. The total average dose at the center of the phantom during the 4-week scanning period was 194.3 mGy. No significant radiation effects were observed in the weight gain curves, organ weights, blood analyses, litter sizes, reared offspring sizes, and the histopathologic results. Therefore, it is unlikely that the measured doses for the CT scans caused any radiation damage in the mice