McMullen A F, Himel V T, Sarkar N K
LSU School of Dentistry, New Orleans, LA.
J Endod. 1990 Jun;16(6):269-72. doi: 10.1016/S0099-2399(06)81628-6.
Endodontic access preparation leads to a significant reduction in crown retention. This study sought to determine whether this retention can be regained after access. Eighteen extracted human maxillary incisors had PFM crowns fabricated. Crowns were cemented, retention measured, recemented, access preparations cut, and retention once again measured. Then, crowns were recemented and accesses restored with dental amalgam and new retention measured. This format allowed each crown to be used as a control of itself. For crowns cemented with zinc phosphate cement and restored with amalgam, a 126% increase over original retention was measured. For crowns cemented with polycarboxylate cement and restored with amalgam, a 237% increase over original retention was measured. For crowns cemented with polycarboxylate cement and restored with amalgam, a 237% increase over original retention was measured. These results suggest that recementing crowns secondary to endodontic access and restoring the access with amalgam regains and even surpasses the original retention.
牙髓治疗的开髓预备会导致冠修复体固位力显著降低。本研究旨在确定开髓后这种固位力能否恢复。制作了18颗拔除的人上颌切牙的烤瓷熔附金属全冠。全冠黏固后测量固位力，再次黏固，制备开髓洞形，然后再次测量固位力。接着，全冠再次黏固，用银汞合金修复开髓洞形并测量新的固位力。这种方式使每个全冠都能作为自身的对照。对于用磷酸锌水门汀黏固并用银汞合金修复的全冠，测量到其固位力比原始固位力增加了126%。对于用聚羧酸锌水门汀黏固并用银汞合金修复的全冠，测量到其固位力比原始固位力增加了237%。对于用聚羧酸锌水门汀黏固并用银汞合金修复的全冠，测量到其固位力比原始固位力增加了237%。这些结果表明，牙髓治疗开髓后重新黏固全冠并用银汞合金修复开髓洞形可恢复甚至超过原始固位力。
