scholarly journals Micro-CT Analysis of Y-TZP Copings Made by Different CAD/CAM Systems: Marginal and Internal Fit

2018 ◽  
Vol 2018 ◽  
pp. 1-4 ◽  
Author(s):  
Rafaella Caramori Saab ◽  
Leonardo Fernandes da Cunha ◽  
Carla Castiglia Gonzaga ◽  
Amanda Mahammad Mushashe ◽  
Gisele Maria Correr
Keyword(s):  
Tetragonal Zirconia ◽  
Micro Ct ◽  
Ceramic System ◽  
Cad Cam ◽  
Ceramic Blocks ◽  
Ct Analysis ◽  
Ct Technology ◽  
Internal Adaptation ◽  
Internal Fit ◽  
Ceramic Crown

Purpose. The aim of the study was to measure the marginal and internal adaptation (MIA) of zirconia copings, made of 4 ceramic systems for CAD/CAM, using microcomputed tomography (micro-CT) technology. Material and Methods. Two identical stainless steel models were used, representing a preparation for full ceramic crown on a lower molar. The master models were then scanned for the production of copings from specific yttrium oxide partially stabilized tetragonal zirconia polycrystal ceramic blocks of each system (n=10): Cerec/inCoris Zi, Sirona; Cercon/Cercon base, Dentsply; Ceramill/Ceramill Zi, Amann Girrbach; and Lava/Lava Frame Zirconia, 3M ESPE. MIA was evaluated measuring 4 points as follows: marginal gap (MG), axial wall gap (AW), axio-occlusal angle gap (AO), and central occlusal area gap (CO). The data were statistically analyzed by ANOVA and Tukey’s test (α = 0.05). Results. The ceramic system Lava showed greater internal desadaptation (80.75 ± 22.69 µm) while CEREC presented the lowest values (49.92 ± 11.77 µm). There were significant differences between the measurement points evaluated. CO demonstrated the greater values (77.03 ± 22.61 µm). All marginal and internal adaptation values were considered clinically acceptable. Conclusion. It was concluded that there was an influence of the type of ceramic system in marginal and internal adaptation of copings in zirconia.

scholarly journals Digital Procedures Compared to Conventional Gypsum Casts in the Manufacturing of CAD/CAM Adhesive Restorations: 3D Surface Trueness and Interfacial Adaptation Analysis

2021 ◽  
Vol 11 (11) ◽  
pp. 5060
Author(s):  
Andrea Baldi ◽  
Allegra Comba ◽  
Edoardo Alberto Vergano ◽  
Michail L. Vakalis ◽  
Mario Alovisi ◽  
...  
Keyword(s):  
Ct Scan ◽  
Ex Vivo ◽  
Micro Ct ◽  
Marginal Fit ◽  
Cad Cam ◽  
Ct Analysis ◽  
3D Printed ◽  
Tooth Preparation ◽  
Internal Fit ◽  
Ex Vivo Study

Objective. The purpose of this ex vivo study was to compare the trueness of traditional and digital workflows and to analyze the interfacial fit of CAD/CAM restorations on gypsum and 3D-printed casts (3DC). Methods: Forty patients underwent indirect posterior adhesive restorations. After tooth preparation, both traditional and chairside procedures were followed. Obtained models were scanned to generate STL files of the intraoral impression (IOS), the conventional cast (RS), and the 3D-printed cast (3DCS). Superimposition of the casts was performed to evaluate trueness. Then, for each preparation, two identical CAD/CAM restorations were milled and luted on RS and 3DC. Micro-CT scan was performed to evaluate 3D interfacial fit. Results. Surface trueness analysis showed no significant differences among groups (p > 0.05), with average trueness ranging from 11.56 to 17.01 µm. Micro-CT analysis showed significant differences between gypsum casts (average ranging from 135.78 to 212.31 µm) and 3DC (average ranging from 57.63 to 144.55 µm) for both marginal and internal fit. Conclusions. In adhesive restorations manufacturing, digital and conventional procedures generate casts that are not significantly different. Marginal fit of adhesive restorations is similar to conventional crown design and clinically acceptable. It is assumable that a direct digital workflow could benefit from the usage of 3DC.

scholarly journals Integrative description of two new species of Malagasy chirping giant pill-millipedes, genus Sphaeromimus (Diplopoda: Sphaerotheriida: Arthrosphaeridae)

2017 ◽  
Author(s):  
Leif Moritz ◽  
Thomas Wesener
Keyword(s):  
New Species ◽  
Coi Gene ◽  
Micro Ct ◽  
Mitochondrial Coi ◽  
Taxonomic Description ◽  
Mitochondrial Coi Gene ◽  
Two New Species ◽  
Ct Analysis ◽  
Ct Technology ◽  
First Time

The species-rich giant pill-millipedes (Sphaerotheriida) often represent a microendemic component of Madagascar’s mega-invertebrate fauna. Of the chirping genus Sphaeromimus de Saussure & Zehntner, 1902, ten species have been described. Here, we describe two new species of Sphaeromimus integratively, combining light microscopy, scanning electron microscopy, DNA barcoding and micro-CT technology for the first time in a taxonomic description of a giant pill-millipede. S. kalambatritra sp. nov. and S. midongy sp. nov. are the first giant pill-millipedes collected and described from the mountainous rainforests of Kalambatritra and Midongy. Both species show island gigantism compared to their congeners. Our analysis of the mitochondrial COI gene shows that the two species are related to one another with a moderate genetic distance (9.4%), while they are more closely related to an undetermined specimen from the forest of Vevembe (6.3% and 8.4%). They stand in a basal position with S. ivohibe Wesener, 2014 and S. musicus (de Saussure & Zehntner, 1897). The four aforementioned species share a high number of stridulation ribs on the male harp. Our micro-CT analysis provides a look into the head of S. kalambatritra sp. nov. and shows that non-destructive CT methods are a useful tool for studying the inner morphology of giant pill-millipedes.

Marginal Fit Evaluation of CAD/CAM All Ceramic Crowns Obtained by Two Digital Workflows: An In Vitro Study Using Micro‐CT Technology

2019 ◽  
Vol 28 (9) ◽  
pp. 1037-1043 ◽  
Author(s):  
Ibrahim Salim Duqum ◽  
Christian Brenes ◽  
Gustavo Mendonca ◽  
Thiago Almedia Prado Naves Carneiro ◽  
Lyndon F. Cooper
Keyword(s):  
In Vitro Study ◽  
Vitro Study ◽  
Micro Ct ◽  
Marginal Fit ◽  
All Ceramic ◽  
Cad Cam ◽  
Ct Technology ◽  
Ceramic Crowns

scholarly journals Influence of Manufacturing Methods of Implant-Supported Crowns on External and Internal Marginal Fit: A Micro-CT Analysis

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Izabela C. M. Moris ◽  
Silas Borges Monteiro ◽  
Raíssa Martins ◽  
Ricardo Faria Ribeiro ◽  
Erica A. Gomes
Keyword(s):  
Qualitative Evaluation ◽  
Insertion Torque ◽  
Micro Ct ◽  
Marginal Fit ◽  
Manufacturing Method ◽  
Significant Difference ◽  
Cad Cam ◽  
Computed Microtomography ◽  
Ct Analysis ◽  
Manufacturing Methods

Aim.To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography.Methods.Forty external hexagon implants were divided into 4 groups(n=8), according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machining. The crowns were attached to the implants with insertion torque of 30 N·cm. The external (vertical and horizontal) marginal fit and internal fit were assessed through computed microtomography. Internal and external marginal fit data (μm) were submitted to a one-way ANOVA and Tukey’s test(α=.05). Qualitative evaluation of the images was conducted by using micro-CT.Results.The statistical analysis revealed no significant difference between the groups for vertical misfit(P=0.721). There was no significant difference(P>0.05)for the internal and horizontal marginal misfit in the groups GC, GI, and GP, but it was found for the group GCAD(P≤0.05). Qualitative analysis revealed that most of the samples of cast groups exhibited crowns underextension while the group GCAD showed overextension.Conclusions.The manufacturing method of the crowns influenced the accuracy of marginal fit between the prosthesis and implant. The best results were found for the crowns fabricated through CAD/CAM machining.

Evaluation of marginal and internal fit of ceramic and metallic crown copings using x-ray microtomography (micro-CT) technology

2015 ◽  
Vol 114 (2) ◽  
pp. 223-228 ◽  
Author(s):  
Manuel Antonio Pimenta ◽  
Luis Carlos Frasca ◽  
Ricardo Lopes ◽  
Elken Rivaldo
Keyword(s):  
Micro Ct ◽  
X Ray ◽  
Ct Technology ◽  
Internal Fit

Marginal and internal adaptation of ceramic crown restorations fabricated with CAD/CAM technology and the heat-press technique

2014 ◽  
Vol 112 (2) ◽  
pp. 249-256 ◽  
Author(s):  
Hisham A. Mously ◽  
Matthew Finkelman ◽  
Roya Zandparsa ◽  
Hiroshi Hirayama
Keyword(s):  
Cad Cam ◽  
Internal Adaptation ◽  
Ceramic Crown

scholarly journals The affects of cement space thickness and material type with application of micro-CT scanner on marginal discrepancy of restoration

2020 ◽  
Vol 24 (1) ◽  
Author(s):  
Mosharraf Mosharraf ◽  
Amir Azizi ◽  
Babak Naziri ◽  
Majid Abolhasani
Keyword(s):  
Clinical Success ◽  
Micro Ct ◽  
Ct Scanner ◽  
3D Scanner ◽  
Cad Cam ◽  
Monolithic Zirconia ◽  
Marginal Discrepancy ◽  
Spss Software ◽  
Internal Fit

Objective: Studies demonstrated that as one of the newly developed restorative materials, monolithic zirconia resolved several issues of zirconia restoration. Therefore, marginal accuracy and internal fit are necessary for clinical success and quality of restorations, and cement space may influence the marginal fit. Thus, the present research aimed to investigate the effects of the cement thickness and kind of restoration on the marginal discrepancy. Material and methods: In this study, 20 maxillary left first molars, prepared by DRSK Co., were used to fabricate a full crown. Two types of material included monolithic zirconia (Zolid) and Sintron were used to make a full crown. Samples from each group were scanned by dental laboratory 3D scanner and designed and processed using CAD-CAM. The samples were divided into four groups of five with 30- and 50- µm cement spaces. In order to assess the vertical marginal discrepancy, the crowns were fitted on their respective teeth without using any mediator and examined by a micro-CT scanner. Data were analyzed by SPSS software. Results: It has been found that marginal discrepancy in Sintron is higher than the discrepancy of monolithic zirconia. In fact, monolithic zirconia with 50-micron cement space exhibited the least marginal discrepancy and the cement space in Sintron did not significantly influence the marginal discrepancy. Conclusion: It has been concluded that the material kinds and cement space influence the restoration marginal discrepancy constructed by digital workflow.  KEYWORDSDental cements; Dental marginal adaptation; X-Raymicrotomography.

scholarly journals Effect of different impression methods and ceramic materials on adaptation of inlays

2018 ◽  
Vol 21 (3) ◽  
pp. 296
Author(s):  
Marília Pivetta Rippe ◽  
Elen Guerra ◽  
Arianne Vallim Pinto Coelho ◽  
Lilian Costa Anami ◽  
Renata Marques de Melo Marinho ◽  
...  
Keyword(s):  
Lithium Disilicate ◽  
Ceramic Materials ◽  
Digital Impression ◽  
Marginal Adaptation ◽  
Digital Impressions ◽  
Cad Cam ◽  
Ceramic Blocks ◽  
Dental Impression ◽  
Internal Adaptation ◽  
Ceramic Inlay

<p><strong>Objective:</strong> The aim of this study was to evaluate the internal and marginal adaptation of inlays fabricated from different types of impressions (conventional and digital) and different ceramics (feldspathic and lithium disilicate). <strong>Material and Methods:</strong> Forty premolars were prepared for all-ceramic inlay restoration and assigned to 4 groups (n=10), according to the impression method (conventional with addition silicone and digital impressions) and ceramic type (lithium disilicate and feldspathic ceramic blocks). For each type of impression, 10 inlays were fabricated from lithium disilicate blocks and the other 10 from feldspathic ceramic blocks, by means of the CAD-CAM system. The internal adaptation was analyzed by replica. The marginal fit was analyzed under a stereomicroscope by directly measuring the gap formed between the inlay and the tooth in the proximal and occlusal regions. <strong>Results:</strong> The marginal or internal adaptations were not affected by type of impression (conventional = digital impression), irrespective of the ceramic type. Only the internal adaptation was affected by material, i.e., feldspathic ceramic had lower values than disilicate ceramic, when considering the digital impression. <strong>Conclusion:</strong> The conventional and digital impressions promote similar marginal and internal adaptation of tested feldspathic and disilicate ceramic inlays. For digital impression the feldspathic ceramic showed better internal adaptation than lithium disilicate. </p><p><strong>Keywords</strong></p><p>Ceramics; Dental internal adaptation; Dental marginal adaptation; Dental impression technique.</p>

scholarly journals Influence of Conventional, CAD-CAM, and 3D Printing Fabrication Techniques on the Marginal Integrity and Surface Roughness and Wear of Interim Crowns

2021 ◽  
Vol 11 (19) ◽  
pp. 8964
Author(s):  
Nada Aldahian ◽  
Rawaiz Khan ◽  
Mohammed Mustafa ◽  
Fahim Vohra ◽  
Ali Alrahlah
Keyword(s):  
Surface Roughness ◽  
3D Printing ◽  
Pearson Correlation ◽  
Physical Property ◽  
Mean Value ◽  
Surface Wear ◽  
Micro Ct ◽  
Marginal Integrity ◽  
Cad Cam ◽  
Ct Analysis

The aim is to assess the influence of fabrication techniques—conventional (CN), CAD-CAM (CC), and 3D printing (3D)—on the marginal fit, adaptation, surface roughness, and wear of interim restorations of crowns. Thirty interim crowns were fabricated using CN, CC, and 3D techniques. Sixty discs were fabricated to evaluate surface wear and surface roughness properties, with 10 disc samples in each group (n = 10). Internal adaptation and marginal integrity of interim crowns were analyzed with micro CT to detect microgaps at selected points. Average surface micro-roughness (Ra) was calculated in micrometers (μm) using an optical non-contact surface microscope under cyclic loading. Surface wear was evaluated by surface area measurements (mm3) using a micro CT. Analysis of variance (ANOVA) and Tukey’s post hoc comparison tests with Pearson correlation were performed for data analysis. The highest adaptation means were for CN (269.94 ± 64 μm), and the lowest mean value was observed for 3D (197.82 ± 11.72 μm) crowns. CN and CC specimens showed comparable adaptation (p > 0.05), which were significantly higher (p < 0.05) than 3D crowns. CN crowns showed significantly higher marginal misfit compared to 3D (p < 0.05) and CC (p < 0.05) crowns. The highest mean surface roughness was observed in the 3D crowns (5.61 ± 0.33 µm), whereas the lowest was found in CC crowns (3.28 ± 0.34 µm). Better restoration Ra was observed using the CC method followed by CN. CN had the highest wear (17.79 ± 2.78 mm3), and the lowest wear was observed in the 3D (10.81 ± 2.00 mm3) specimen. Low surface wear was observed using 3D printing, followed by CN and CC techniques. The printed specimen showed comparable outcomes to CAD-CAM restoration; however, they were better than CN restoration. A positive correlation between adaptation and surface roughness was observed, indicating an effect of the fabrication technique on material physical property.

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