直接法和间接法前牙桩核冠修复的临床对比观察

目的：评价用嵌体蜡直接法和用寒天、藻酸盐印模材料联合印模法制取残冠、残根桩核的临床应用。方法：对91例119颗残冠残根分别用嵌体蜡直接法和用寒天联合印模间接法制作桩核。完成后的桩核经临床试戴、黏固后烤瓷全冠修复。结果：嵌体蜡直接法修复76颗牙，成功71颗，失败5颗；间接法修复43颗牙，成功42颗，失败1颗。结论：寒天联合印模法操作简便，印模精确度高，桩核与根管、根面边缘密合性好，固位力强，临床实用性好。

Clinical evaluation of extensively damaged pulpless anterior teeth restored with direct and indirect cast dowel-core crowns

OBJECTIVE: To compare the clinical effects of the restoration of residual crowns and roots with direct and indirect cast dowel-core crowns. METHODS: The direct and indirect techniques were applied to fabricate cast dowel-core in 119 teeth of 91 patients. The direct dowel-cores were made by fabricating wax patterns in the prepared teeth in the patients' mouth; and the indirect dowel-cores were fabricated with wax patterns on casts poured by injecting agar impression material into the canal. Then the completed wax patterns were invested. After finishing the dowel-cores, they were cemented in the teeth. The metalceramic crowns were made to restore these teeth. RESULTS: Of the 119 teeth, 71 succeeded and 5 failed in 76 dowel-cores made by the direct method; and only 1 tooth failed among the 43 dowel-cores made by the indirect method. CONCLUSION: The indirect method using agar impression material can be manipulated easily and conveniently with accurate impressions. The dowel-core fits the root canal and the margin has good adaption. The retention is good and this method is practicable.