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作者从收集到的312颗下颌第一双尖牙中发现畸形根2例(0.64％)。其中1例唇侧颈缘有楔状缺损,牙根于根中、尖1/3交界处分出3根,近中1根、远中2根(附图a),三根分叉,成鼎脚状张开,游标卡尺测冠长7.65mm,根长14.76mm,分叉处距颈缘10.24mm,远中2根根尖间距6.05mm,距近中侧根尖3.82mm与4.92mm。体视显微镜观察每个根尖有2～3个根尖孔。 另一例在牙根舌侧颈缘处分出一细小的额外根(附图b)。额外根根长7.22mm,约为主根全长的1/2,分叉处直径1.55mm,根尖仅一个根尖孔。
The authors found 2 cases (0.64%) of deformed roots from the collected first 312 pairs of mandibular first bicuspids. One case of the labial margin of the lip had a wedge-shaped defect, root in the root, the tip of the junction of 1 out of 3, near 1, far 2 (Figure a), three bifurcation, into a tripod legs Open, vernier caliper measured crown length 7.65mm, root length 14.76mm, bifurcation from the edge of the neck 10.24mm, distance 2 apical 6.05mm, from the proximal apical 3.82mm and 4.92mm. Stereo microscopic observation of each root tip has 2-3 apical foramen. In another case, a small extra root was removed at the lingual margin of the lingual root (Figure b). The extra root length is 7.22mm, about 1/2 of the total length of the main root, 1.55mm in diameter at the bifurcation and only one apical hole in the root tip.