Open AccessMarginal and internal fit evaluation of conventional metal-ceramic versus zirconia CAD/CAM crowns
Author(s) -
Nayana Paul,
KN. Raghavendra Swamy,
MR. Dhakshaini,
S. Sowmya,
M. Meravini
Publication year - 2020
Publication title -
journal of clinical and experimental dentistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.481
H-Index - 23
ISSN - 1989-5488
DOI - 10.4317/jced.55946
Subject(s) - cad , cubic zirconia , ceramic , materials science , metal , dentistry , composite material , medicine , metallurgy , engineering , engineering drawing
Background The purpose of this in vivo study was to compare the marginal and internal gap widths of monolithic zirconia crowns fabricated by CAD/CAM technique and metal-ceramic crowns fabricated by conventional technique.Material and Methods 10 participants needing a single restoration were selected. Zirconia crowns using CAD/CAM technology (Group A) (n=10) and metal-ceramic crowns (Group B) (n=10) using lost wax casting technique were fabricated for each selected tooth. The marginal and internal gaps of crowns were recorded using a replica technique with light body silicone material stabilized with a regular set putty. Each replica was sectioned buccolingually and mesiodistally and then evaluated at five pre-determined sites. The points measured were PM for marginal gap, PA for axial gap, PAO for axio-occlusal transition gap and PO and PCO for occlusal gaps using a stereomicroscope at 30× magnication. The Paired Sample (t) test was used to detect significant differences between the two groups in terms of marginal and internal fit (α= 0.05).Results The mean for the marginal gap was 77.42μm (±39.5μm) for Group A compared with 95.86μm (±55.12μm) for Group B. Mean values for internal gap was 87.24 (±21.7 µm) for Group A and 132.91 µm (± 50.63 µm) for Group B. Significant differences were observed between both the groups for marginal ( p =.010) and internal ( p =.000) fit.Conclusions The CAD/CAM fabricated zirconia crowns demonstrated a better accuracy of fit when compared to metal-ceramic crowns fabricated by conventional technology. Key words: Marginal fit, Internal fit, Computer-aided design/computer-aided manufacturing (CAD/CAM).