华西口腔-修复理想桥基牙 PPT课件

uch a tooth, little opportunity is found to develop sufficient mechanical retention and still not endanger the pulp. It is much better, when such teeth are encountered, to employ plete veneer type of retainer.Р非全冠的桥固位体的结构经常会在一个重度磨损的牙齿上引起严重的机械或生物学问题。过度磨损的牙齿因为降低了冠的高度,很难获得足够的机械固位,也会累及牙髓。当遇到这样的牙齿时,用全贴面类型的固位体会更好。РAt times teeth egress beyond their normal occlusal plane to a point where, to use them as bridge abutments, it is necessary to grind down a considerable portion of the occlusal third of the crown. Such teeth are not usually in occlusal contact with the opposing arch. The amount of such vertical displacement varies from 1mm. to a point where the teeth touch the mucosa of the opposite arch. Р有时牙齿会伸长超过了他们所在的正常的合平面,用他们作为桥基牙时,必须将牙冠合1/3磨去相当多的一部分。这样的牙齿通常和对合牙没有咬合接触。这样的垂直移位的量会从1mm到牙齿接触到对合牙弓的粘膜。