Carter S M, Wilson P R
School of Dental Science, University of Melbourne, Victoria, Australia.
Int J Prosthodont. 1996 Jan-Feb;9(1):21-9.
Ten extracted molar teeth were prepared to a standardised complete crown preparation. Five stone dies were constructed for each tooth and coated with zero, two, four, six, and eight layers of a paint-on die-spacer. Crowns were fabricated on each die and the force required for removal from each tooth was measured prior to cementation. The crown elevation and force required for removal were measured after luting with zinc phosphate cement. The force required to remove the crowns before cementation decreased with increasing layers of die-spacer. Following cementation, the mean crown elevation decreased from 547 micrometers (zero layers) to 38 micrometers (eight layers); while the mean removal force increased from 250 N (zero layers) to 375 N (eight layers).
选取十颗拔除的磨牙进行标准化全冠预备。为每颗牙齿制作五个石膏代型，并分别涂覆零层、两层、四层、六层和八层的刷涂型代型间隙剂。在每个代型上制作全冠，并在粘固前测量从每颗牙齿上取下全冠所需的力。用磷酸锌水门汀粘固后，测量全冠的提升高度和取下所需的力。粘固前取下全冠所需的力随着代型间隙剂层数的增加而减小。粘固后，全冠的平均提升高度从547微米（零层）降至38微米（八层）；而平均取下力从250牛（零层）增至375牛（八层）。
