Comparisons of condylar movements with the functional occlusal clutch and tray clutch recording methods in CADIAX system / 国际口腔科学杂志·英文版

<p><b>AIM</b>The purpose of this study is to compare the effects of the two clutches on recording the condylar movement.</p><p><b>METHODOLOGY</b>Ten subjects (6 women, 4 men; mean age 25.4 years) participated in the study. The mandibular movement, sagittal condylar inclination angle, and transversal condylar inclination angle of each subject were recorded with the CADIAX using the two clutches, respectively. The characteristics of the tracings of the protrusion, opening, and mediotrusion were analyzed with the t-test statistics at a = 0.05 level. The Kappa values were calculated for an assessment of the congruence of the tracings.</p><p><b>RESULTS</b>The results showed that the contour, direction, and dimension of the tracings in the two clutches were approximately same, but the tracings determined by the functional occlusal clutch were more regular and congruent. In the group segment recorded with the tray clutch, opening/closing paths of one subject showed crossed and time curves of three subjects appeared peak-like changes of velocity, but none were statistically different (P>0.05).</p><p><b>CONCLUSION</b>The research suggests that the functional occlusal clutch should be preferred in the evaluation of the mandibular function, as the tracings with the tray clutch are more likely to produce false positive results.</p>

The distribution of collagen I, II, X and alkaline phosphatase in the development of condylar cartilage of fetal mouse mandible / 华西口腔医学杂志

<p><b>OBJECTIVE</b>The purpose of this study was to investigate the distribution of collagen I, II , X, alkaline phosphatase (ALP) and their roles during initiation of condylar cartilage of the fetal mouse.</p><p><b>METHODS</b>Coronary sections of mandible of mouse embryo aged from 14th to 18th day were studied under light microscope after stained by immunohistochemical method with antibody of types I, II, X collagen and ALP.</p><p><b>RESULTS</b>On the 14th day of mouse embryo, it was found that mesenchymal cells condensation continuous with the periosteum. Type I collagen and ALP were positive behind the terminal of the ossifying mandibular periosteum where future condylar will form. On the 15th day, positive staining for types I, II collagen was found in mesenchymal cells around hypertrophic cells and type X collagen was detected in hypertrophic cells. ALP was positive in both mesenchymal cells and hypertrophic cells. On the 16th day, type I collagen was observed from periosteal osteogenic cells and mesenchymal cells of the fibrous cell layer to the upper hypertrophic cell layer while Type II collagen was restricted from the lower polymorphic cell layer to the bottom of the hypertropic cell layer. Type X collagen was positive in the hypertrophic cell layer. ALP was positive in periosteal osteogenic cells and hypertrophic chondral cells, but not in the polymorphic cell layer.</p><p><b>CONCLUSION</b>Development of condylar cartilage is different from that of limb bone. Types I, II, X collagen are expressed in the condylar chondrocyte on the early stage of endochondral ossification. The histology evidence supports the conjecture that condylar cartilage is derived from differentiated mesenchymal cells of the preperiosteum or periosteum of the mandible where ALP is positively expressed.</p>