Comparison of the Marginal Fit of Pressable Ceramic to Metal Ceramic Restorations

• Published in: Journal of prosthodontics 2009-12, Vol.18 (8), p.645-648
• Main Authors: Holden, Jason E., Goldstein, Gary R., Hittelman, Eugene L., Clark, Elizabeth A.
• Format: Article
• Language: English
• Subjects: all-ceramic; Aluminum Silicates - chemistry; Ceramics - chemistry; Crowns; Dental Marginal Adaptation - standards; Dental Models; Dental Porcelain - chemistry; Dental Prosthesis Design; Dentistry; Humans; Incisor; marginal fit; marginal opening; Materials Testing; Metal Ceramic Alloys - chemistry; Potassium Compounds - chemistry; Surface Properties; Tooth Preparation, Prosthodontic
• ISSN: 1059-941X; 1532-849X
• DOI: 10.1111/j.1532-849X.2009.00497.x

Purpose: The aim of this in vitro study was to compare the marginal adaptation of a pressed ceramic material, when used with and without a metal substructure, to a traditional feldspathic porcelain‐fused‐to‐metal restoration with a porcelain butt margin. Materials and Methods: A maxillary central incisor typodont tooth was prepared with a 1.5 mm 360° shoulder with rounded internal line angle, and 30 polyether impressions were made. Dies were poured in type IV dental stone, and 30 restorations were fabricated: 10 metal ceramic restorations (MCR) with porcelain butt joints, 10 pressed to metal restorations (PTM), and 10 all‐ceramic restorations (PCR). All restorations were evaluated on their respective dies at 45× magnification using an Olympus SZX‐12, measurements of the marginal openings were made, and ANOVA and Scheffé post hoc tests were used to evaluate the data. Results: The mean marginal opening was 72.2 ± 5.9 μm for MCR, 49.0 ± 5.9 μm for PTM, and 55.8 ± 5.9 μm for PCR. The post hoc tests showed that there was a statistical difference between the marginal adaptation of the PTM and MCR groups (p < 0.05). There was no significant difference in marginal adaptation between the PTM and the PCR groups, or the PCR and the MCR groups. Conclusions: The PTM group demonstrated a smaller mean marginal opening than the MCR group. The mean marginal openings of all three groups were within a clinically acceptable range.