Post Crow and PostCore Crown口腔修复学

1、zhu ziyuanstaff room of prosthodonticslpost crown (dowel crown) lpost-core crown (dowel-core crown, post and core system )uwhats the post crown and post-core crown?uwhats the difference between the post crown and post-core crown?uwhen do people need one?uwhat influence the retention and strength?uwh

2、ats the point of tooth preparing?uhow to fabricate it? 是利用冠桩插入根管内以获得是利用冠桩插入根管内以获得固位的一种冠修复体。固位的一种冠修复体。uchange crown without change postuchange direction of the toothurestore the extensive tooth defect with full crownu perfect rct ( root canal therapy 根管治疗根管治疗)u12 weeks after rct completedu fistula ci

3、catrizedu lesion around apex limitedu extensively damaged toothuthe defect is in subgingival areauanterior tooth fracture（trauma）umalposition (错位错位) or torsiversion (torsoclusion 扭转扭转) umalformed (畸形畸形) tooth uas a retainer for fpd( fixed partial denture 固定义齿固定义齿)u age under 18u inflammation with cl

4、inical symptomu severe bone absorption (1/3 of root)u the root canal is curved and tinyua lateral cleft in root cannel uan oblique fracture under alveolar crest uthe broken post can not be taken out.udeep bite, compact occlusion.ulength: 2/3-3/4 length of the rootu4mm apical seal remainedulength of

5、the post length of the crownulength of the post inside alveolar 1/2 length of the root inside alveolar udiameter: 1/3 of the roots diameteru cross section shapeu external shapeu parallel postu cone-shaped postu trapeziform postu external shapeu smooth postu screwed postu serrated postsmooth post scr

6、ewed post udentinal ferruleudentinal ferruleumetal post-corecast metal post-corepreformed ( prefabricated ) post-coreunon-metal post-coreglass fiber postcarbon fiber postceramic postucoronal portion preparationreduce the tooth with crown preparation ucoronal portion preparationremove all cariesucoronal portion preparationremove unsupported tooth structureucanal preparationuroot surface preparationuimpression of cast post-coreudirect method( metal post-core)uimpression of cast post-coreudirect method( metal post-core)uimpression of cast post-coreudirect method( posteri