Yamashita J, Shiozawa I, Takakuda K, Miyairi H
Department of Fixed Prosthodontics, Faculty of Dentistry, Tokyo Medical and Dental University, Japan.
Int J Prosthodont. 1997 Jul-Aug;10(4):332-9.
This study investigated fractures of the cement layer between a crown and a die. Model crowns were luted on dies with zinc phosphate cement and various magnitudes of load were applied. Surface strain on the crown was measured using strain gauges. Seal was evaluated using dye penetration and tensile tests. Results showed that cement fracture affected surface strain behavior on the crown and was detected using the surface strain measurement. The dye penetration test and the tensile test could not be used to detect the cement fracture. It is suggested that the three-dimensional relative positioning between the crown and the die affected the development of the cement fracture.
本研究调查了牙冠与代型之间水门汀层的断裂情况。用磷酸锌水门汀将模型牙冠粘结在代型上，并施加不同大小的载荷。使用应变片测量牙冠表面应变。通过染料渗透试验和拉伸试验评估密封性。结果表明，水门汀断裂会影响牙冠表面应变行为，且可通过表面应变测量检测到。染料渗透试验和拉伸试验无法用于检测水门汀断裂。提示牙冠与代型之间的三维相对位置会影响水门汀断裂的发展。
