Fit accuracy between zirconia abutments and zirconia crowns  
Li Wei1, Yang Jian-jun2, Wang Da-shan2, Liu Guang-yuan1, Yang Zhen1, Li Ting1
Chinese Journal of Tissue Engineering Research . 2012, (21): 3903 -3906 .  DOI: 10.3969/j.issn.1673-8225.2012.21.024