scholarly journals Influence of finish line design on the marginal fit of nonprecious metal alloy coping fabricated by 3D printing, milling and casting using CAD CAM

2018 ◽  
Vol 29 ◽  
pp. 281-281
Author(s):  
Ayoung Ahn ◽  
Jai-Young Kowk ◽  
Seong-Joo Heo ◽  
Seong-Kyun Kim
Author(s):  
Jaber Hussain Akbar ◽  
Ridwaan Omar ◽  
Yacoub Al Tarakmah

Statement of problem- Research on evaluation of crowns made by the latest CAD/CAM systems for their marginal adaptation is scarce. Purpose- The purpose of this in vitro study was to evaluate the marginal integrity of crowns fabricated by the latest Chairside Economical Restorations of Esthetic Ceramic (CEREC) system using two different finish line preparation designs: Chamfer and Shoulder. Material and methods- Typhodont teeth were equally divided into two groups, group A and B. The teeth were prepared for full coverage crowns with a shoulder (group A) and chamfer finish line design (group B). An experienced prosthodontist prepared all crown preparations. Evaluation of six sites per sample was completed by two calibrated, experienced prosthodontists using the modified United States Public Health Services (USPHS) criteria. The descriptive statistics and Z-test were used to evaluate the results. Results- A total of 180 teeth were included in the study (90 teeth in each group). Only two crowns in group A and one crown in group B were clinically unacceptable. There was no statistical significance (p=0.282) between the two groups regarding finish-line design. Conclusions- CEREC system provides clinically acceptable crowns and can safely be utilized in dental treatment. Therefore, Contemporary Dental Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) restorations should be considered as a safe treatment modality by dental professionals.


2012 ◽  
Vol 06 (02) ◽  
pp. 163-168 ◽  
Author(s):  
Gulce Subasi ◽  
Nilgun Ozturk ◽  
Inan Ozgur ◽  
Nalan Bozogullari

ABSTRACTObjectives: This in-vitro study investigated the marginal fit of two all-ceramic copings with 2 finish line designsMethods: Forty machined stainless steel molar die models with two different margin designs (chamfer and rounded shoulder) were prepared. A total of 40 standardized copings were fabricated and divided into 4 groups (n=10 for each finish line-coping material). Coping materials tested were IPS e.max Press and Zirkonzahn; luting agent was Variolink II. Marginal fit was evaluated after cementation with a stereomicroscope (Leica MZ16). Two-way analysis of variance and Tukey-HSD test were performed to assess the influence of each finish line design and ceramic type on the marginal fit of 2 all-ceramic copings (α =.05) Results: Two-way analysis of variance revealed no statistically significant differences for marginal fit relative to finish lines (P=.362) and ceramic types (P=.065)Conclusion: Within the limitations of this study, both types of all-ceramic copings demonstrated that the mean marginal fit was considered acceptable for clinical application (≤120 μm). (Eur J Dent 2012;6:163-168)


2019 ◽  
Vol 122 (2) ◽  
pp. 143-151 ◽  
Author(s):  
Adel Al Maaz ◽  
Geoffrey A. Thompson ◽  
Carl Drago ◽  
Hongseok An ◽  
David Berzins

2020 ◽  
Vol 18 ◽  
pp. 228080002092451
Author(s):  
Khulud A Al-Aali ◽  
Mohammed S. Bin-Shuwaish ◽  
Aasem M Alhenaki ◽  
Khold Al Ahdal ◽  
Laila Al Deeb ◽  
...  

Objective: The aim of this study was to evaluate marginal fit of yttrium tetragonal zirconia polycrystals (Y-TZP)’ copings with different finish line designs fabricated with various digital scanners and milling systems. Methods: Three model plastic teeth were prepared with three finish line designs: Design-1, continuous chamfer; Design-2, chamfer with shallow depression; Design-3, chamfer with deep depression. The “master models” were replicated using elastomeric polyvinyl siloxane impression material and poured in type IV stone generating 90 dies, 30 dies for each design. Dies were scanned and copings were milled utilizing three digital scanners and computer-aided design/computer-aided manufacturing (CAD/CAM) systems: System-1, InEos Red Scan (Sirona Dental Systems, Germany), Vitablocks® Mark II (VITA, Germany) copings milled by Cerec® inLab (Sirona Dental Systems, Germany); System-2, Cerec® AC Connect with BlueCam (Sirona Dental Systems, Germany), Vitablocks® Mark II (VITA, Germany) copings milled by Cerec® inLab (Sirona Dental Systems, Germany); and System-3, NobleProcera™ Optical Scanner (NobleBiocare™), procera zirconia coping milled by a Noble Procera™ milling machine (NobleBiocare™). Copings were seated on their respective “master models” and secured with uniform force. Eight measurements per coping were performed at pre-established points, with a metallurgical microscope (Zeiss, Germany) connected to a high precision digital video-micrometer (Javelin JV6000, California, USA) at 200 × magnification. Results: The tested systems demonstrated marginal gaps ranging from 12.4 to 26.6 µm. Results for marginal fit of milled copings fabricated using three systems with different finish line designs differed significantly ( p < 0.05). Procera zirconia copings scanned and milled with NobleProcera™ exhibited significantly lower marginal gaps compared to other specimen groups. However, InEos Red Scan/Vitablocks® Mark II/Cerec® inLab showed maximum marginal gaps among the study specimens. Conclusions: CAD-CAM manufactured Y-TZP’ copings exhibited marginal gaps ranging from 12.49 to 26.6 µm. The CAD-CAM fabrication system was a significant factor influencing the marginal misfit of Y-TZP’ copings. Margin design exhibited system dependent influence on the marginal misfit. Marginal misfit observed for all systems were within clinically acceptable parameters.


2020 ◽  
Vol 23 (3) ◽  
Author(s):  
Mohamed Eldamaty ◽  
Mohammed Abdel-Aziz ◽  
Ahmed El-Kouedi ◽  
Tamer Hamza

Objective: The purpose of this study was to evaluate the effect of finish line design and cement space thickness on the marginal accuracy of monolithic zirconia crowns. Materials and methods: Thirty crowns were fabricated from translucent zirconia (inCoris TZI) using Cerec in-Lab system and divided into three main groups (10 each) according to the finish line type of the die (knife-edge, chamfer, and shoulder). Every group was divided into two subgroups (5 each) according to cement space thickness (20 and50μm). Optical impressions were taken for the dies using the Cerec scanner and cement space was set twice for every finish line design; 20 and 50 μm. The completed crowns were cemented to the dies and the marginal gap was evaluated. The collected data was statistically analyzed using Mann-Whitney U test and Kruskal-Wallis test and the significance level was set at P ≤ 0.05. Results: Regarding the marginal gap; there was no statistically significant difference between different finish line designs or between different cement space thicknesses. Conclusion: Neither finish line design nor cement space thickness has an effect on the marginal gap of inCoris TZI crowns.KeywordsCement space; Finish line; Marginal fit; Monolithic zirconia.


2014 ◽  
Vol 112 (2) ◽  
pp. 155-162 ◽  
Author(s):  
Raúl Euán ◽  
Oscar Figueras-Álvarez ◽  
Josep Cabratosa-Termes ◽  
Rogelio Oliver-Parra

Author(s):  
A.V. Stomatov ◽  
D.V. Stomatov ◽  
P.V. Ivanov ◽  
V.V. Marchenko ◽  
E.V. Piitsky ◽  
...  

In this work, the authors studied and compared the two main methods used in dental practice for the automated production of orthopedic structures: the widely used CAD / CAM milling method and the 3D printing technology. As an object of research, temporary crowns were used, which were made on the basis of the same digital model: a) by the method of CAD / CAM milling from polymethylmethacrylate disks; b) by 3D printing from photopolymer resin based on LCD technology. Comparison of production methods and finished designs was carried out according to the following characteristics: strength, durability, aesthetic qualities, accuracy of orthopedic designs, etc. According to the results of the study, it was concluded that 3D printing can be a good alternative to CAD / CAM milling in solving problems of temporary prosthetics.


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