Suliman A A, Boyer D B, Lakes R S
Department of Conservative Dentistry, College of Dentistry, University of Mosul, Iraq.
J Dent Res. 1993 Nov;72(11):1532-6. doi: 10.1177/00220345930720111201.
A Michelson interferometry apparatus was used for measurement of the displacement of the buccal cusps of premolars after restoration of MOD preparations with composites. The effects of composite type, cavity size, and hydration conditions were examined. Interferometry permitted real-time measurement of cusp movement as it occurred. Contraction occurred very rapidly, about 1/3 of the 60-minute amount within the two-minute period of exposure to the curing light. Cusp movement was smooth rather than interrupted, indicating lack of microfracturing at deformations of 11-46 microns. Contraction, 0.94% for Heliomolar and 1.2% for P-50, was similar to the linear polymerization shrinkage of the resins. Less cusp movement occurred in small cavities than in large cavities. Hydrated teeth had less cusp movement than dehydrated teeth.
使用迈克尔逊干涉仪装置测量用复合材料修复MOD洞形后的前磨牙颊尖位移。研究了复合材料类型、洞腔大小和水化条件的影响。干涉测量法能够实时测量尖部移动情况。收缩发生得非常迅速，在暴露于固化光的两分钟内，收缩量约为60分钟总量的1/3。尖部移动平稳而非间断，表明在11 - 46微米变形时没有微裂纹。Heliomolar材料的收缩率为0.94%，P - 50材料为1.2%，与树脂的线性聚合收缩率相似。小洞中尖部移动比大洞中的少。湿牙齿的尖部移动比干牙齿的少。
