Clinical marginal and internal gaps of Procera AllCeram crowns

Abstract

This study evaluated the marginal and internal gaps of Procera AllCeram crowns in vivo using silicone materials. Ninety Procera AllCeram crowns were evaluated before final cementation. White and black silicone materials were used to record the marginal and internal fit; then the crowns were sectioned bucco-lingually and mesio-distally to measure the thickness of the silicone layer using a microscope. Sixteen reference points were measured on each specimen. Mean marginal gaps among anterior, premolar and molar teeth, and mean gaps at the reference points within the groups were compared by analysis of variance and Dunnett T3 test. The mean values at the margins were the smallest in all tooth groups, whereas those at the rounded slope of the chamfer were the largest. There were significant differences (P < 0.001) in the mean gaps at the four reference points (margin, rounded slope of the chamfer, axial wall and occlusal surface) in each group, except for the molar teeth. The mean marginal gaps of the Procera AllCeram crowns were within the range of clinical acceptance.

Evaluation of the adaptation of zirconia-based fixed partial dentures using micro-CT technology

“…There is a consensus between a series of studies that a marginal opening below 120 µm is clinically acceptable. 3,27,28 In this study, a mean marginal gap of 47 µm was found, which is well below the clinical threshold. This is an important finding since the marginal adaptation is an important criterion for the success of all-ceramic restorations in the long term.…”

Vertical marginal gap &amp; retention of ceramic full coverage &amp; inlay retained ceramic fixed partial dentures

“…Mechanical strength was reported in several researches [12,[56][57][58]. Several researchers have reported marginal gaps both in vitro and in vivo [59][60][61]. The large gap may cause cement solubility and result in plaque accumulation, marginal leakage, second caries, and eventually crown failure [62,63].…”

Fit of zirconia all-ceramic crowns with different cervical margin designs, before and after porcelain firing and glazing

“…The vertical gap between the restoration prosthesis and the die has been measured in previous evaluations of the fit of crown prostheses. Therefore, we measured gaps between the crown prostheses and dies to permit comparison with other reports 1,10,[19][20][21][22][23] . Fitness tests were performed for three abutment teeth with different cervical margin designs.…”