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 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.

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 Marginal and internal fit and intaglio surface trueness of interim crowns fabricated from tooth preparation of four finish line locations

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Keunbada Son ◽  
Young-Tak Son ◽  
Ji-Min Lee ◽  
Kyu-Bok Lee
Keyword(s):  
Three Dimensional ◽  
Clinical Situation ◽  
Intraoral Scanner ◽  
Replica Technique ◽  
Finish Line ◽  
Marginal Fit ◽  
Tooth Preparation ◽  
The Right ◽  
Internal Fit ◽  
Marginal Region

AbstractThis study evaluated the marginal and internal fit and intaglio surface trueness of interim crowns fabricated from tooth preparation scanned at four finish line locations. The right maxillary first molar tooth preparation model was fabricated using a ceramic material and placed in four finish line locations (supragingival, equigingival, subgingival, and subgingival with a cord). Intraoral scanning was performed. Crowns were designed based on the scanned area. Interim crowns were fabricated using a stereolithography three-dimensional (3D) printer (N = 16 per location). Marginal and internal fit were evaluated with a silicone replica technique. Intaglio surface trueness was evaluated using a 3D inspection software. One-way analysis of variance and Tukey HSD test were performed for comparisons (α = 0.05). The marginal and internal fit showed significant differences according to locations (P < 0.05); the marginal fit showed the best results in the supragingival finish line (P < 0.05). Intaglio surface trueness was significantly different in the marginal region, with the highest value in the subgingival location (P < 0.05). Crowns fabricated on the subgingival finish line caused inaccurate marginal fit due to poor fabrication reproducibility of the marginal region. The use of an intraoral scanner should be decided on the clinical situation and needs.

scholarly journals In Vitro Comparison of Marginal and Internal Fit of Zirconia Copings Fabricated by One CAD/CAM System with Two Different Scanners

2021 ◽  
Author(s):  
Zahra Khamverdi1 ◽  
Elmira Najafrad ◽  
Maryam Farhadian
Keyword(s):  
T Test ◽  
Marginal Fit ◽  
Significant Difference ◽  
Computer Aided ◽  
Cad Cam ◽  
Zirconia Crowns ◽  
Monolithic Zirconia ◽  
The Mean ◽  
Internal Fit ◽  
Paired T Test

Objectives: Marginal and internal fit of restorations are two important clinical factors for assessing the quality and durability of computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated monolithic zirconia restorations. The purpose of this study was to evaluate the marginal and internal fit of CAD/CAM zirconia crowns with two different scanners (i3D scanner and 3Shape D700). Materials and Methods: Twelve extracted sound human posterior teeth were prepared for full zirconia crowns. Two different extraoral scanners namely i3D scanner and 3Shape D700 were used to digitize type IV gypsum casts poured from impressions. The crowns were milled from presintered monolithic zirconia blocks by a 5-axis milling machine. The replica technique and MIP4 microscopic image analysis software were utilized to measure the marginal and internal fit by a stereomicroscope at ×40 magnification. The collected data were analyzed by paired t-test. Results: The mean marginal gap was 203.62 μm with 3Shape D700 scanner and 241.07 μm with i3D scanner. The mean internal gap was 192.30 μm with 3Shape D700 scanner and 196.06 μm with i3D scanner. The results of paired t-test indicated that there was a statistically significant difference between the two scanners in marginal fit (P=0.04); while, there was no statistically significant difference in internal fit (P=0.761). Conclusion: Within the limitations of this study, the results showed that type of extraoral scanner affected the marginal fit of CAD/CAM fabricated crowns; however, it did not have a significant effect on their internal fit.

Additive vs. Subtractive CAD/CAM Procedures in Manufacturing of the PMMA Interim Dental Crowns. A Comparative in vitro Study of Internal Fit

2020 ◽  
Vol 71 (1) ◽  
pp. 405-410
Author(s):  
Kamel Earar ◽  
Alexandru Andrei Iliescu ◽  
Gabriela Popa ◽  
Andrei Iliescu ◽  
Ioana Rudnic ◽  
...  
Keyword(s):  
In Vitro Study ◽  
Dimensional Accuracy ◽  
Vitro Study ◽  
Dental Crowns ◽  
S 100 ◽  
Cad Cam ◽  
Dental Models ◽  
3D Printed ◽  
Internal Fit

CAD/CAM procedures are increasingly used to the manufacturing of 3D-designed PMMA interim dental crowns. The aim of this in vitro study was to compare the internal fit of interim PMMA crowns fabricated by subtractive versus additive CAD/CAM procedures. Starting from a Co-Cr CAD/CAM master abutment model, 20 standardized dental models of dental stone were done by double impression technique. Subsequently two groups of interim PMMA interim crowns, each of them having 10 specimens, were CAM obtained either by milling or 3D printing, using Exocad software package, milling machine Rolland DWX-50, and the 3D printer MoonRay S 100 respectively. An electronic digital caliper Powerfix Profi+ was used for measurements of the chrome cobalt abutment and crowns inner diameter in 4 directions (mesial-distal gingival, buccal-lingual gingival, mesial-distal occlusal, and buccal-lingual occlusal). The null hypothesis that the internal dimensional accuracy of interim PMMA crowns fabricated by DLP additive method would not be different compared to those obtained by milling procedure was rejected since the printed PMMA interim crowns were more accurate. This study concluded that the milled PMMA interim crowns show larger internal dimensional variations than the 3D printed ones. However, the fit variation among interim crowns fabricated by both procedures was statistically non significant, so that both CAM technologies may be equally used in manufacturing process.

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

Tooth and root size as determined from 0.25- and 0.30-mm voxel size cone-beam CT imaging when contrasted to micro-CT scans (0.06 mm): An ex vivo study

2021 ◽  
pp. 146531252110661
Author(s):  
Gaston F Coutsiers Morell ◽  
Yuli Berlin-Broner ◽  
Carlos Flores-Mir ◽  
Giseon Heo
Keyword(s):  
Repeated Measures ◽  
Root Resorption ◽  
Ex Vivo ◽  
Imaging Modality ◽  
Cone Beam Ct ◽  
Three Dimensional ◽  
Cone Beam ◽  
Micro Ct ◽  
Voxel Size ◽  
Ex Vivo Study

Objective: To quantify tooth volume differences from extracted teeth when using three different three-dimensional (3D) computed tomography (CT)-based imaging modalities. Design: Ex vivo study. Setting: Laboratory and clinics of the University of Alberta. Methods: Cone-beam CT (CBCT) of 12 extracted teeth were scanned using 0.25- and 0.30-mm voxel size from CBCT and a 0.06-mm voxel size from micro-CT (reference standard). 3D reconstructions for each tooth from each imaging modality were made through the software ITK-SNAP®. The mean volume differences between each pair of scanning modalities were calculated and then compared and analysed through a repeated measures ANOVA. Results: The average overestimations of the teeth volume were 15.2% for the high-resolution CBCT and 28.1% for the low-resolution CBCT compared to micro-CT measurements. The differences in absolute volume were 81.6 mm3 and 152.8 mm3, respectively. All differences were statistically significant ( P < 0.05). Conclusions: Orthodontists and researchers who assess root resorption through CBCT imaging should be aware that the depicted volumes may likely be overestimating tooth volume and camouflaging real root volumetric treatment changes.

Marginal Integrity, Internal Adaptation and Compressive Strength of 3D Printed, Computer Aided Design and Computer Aided Manufacture and Conventional Interim Fixed Partial Dentures

2019 ◽  
Vol 9 (12) ◽  
pp. 1745-1750
Author(s):  
Laila Al Deeb ◽  
Khold Al Ahdal ◽  
Ghaith Alotaibi ◽  
Abdullah Alshehri ◽  
Bader Alotaibi ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Computer Aided Design ◽  
Outer Edge ◽  
Marginal Fit ◽  
Marginal Integrity ◽  
Computer Aided ◽  
Cad Cam ◽  
3D Printed ◽  
Internal Adaptation ◽  
Aided Design

The aim was to investigate the marginal fit, internal adaptation and compressive strength of SLA provisionals (SLA) in comparison to CAD-CAM and conventional (CONV) interim fixed partial dentures (FPDs). Thirty interim FPDs were fabricated using CAD-CAM technology (CAD-CAM blocks Ceramill TEMP, PMMA), conventional molding technique (CONV) (TrimPlus, PMMA) and Stereolithography (SLA) method (Form 2, Formlabs, PMMA) (n = 10). Internal adaptation (occlusal, coronal, middle and cervical) and marginal integrity (inner and outer edge) was assessed using micro-computerized tomography (Micro-CT). The failure and compressive strength was assessed by application of a static load at a crosshead speed of 1 mm/min until fracture. Data was analysed using ANOVA and multiple comparisons test. The maximum and minimum marginal mis-fit was for CONV (283.3± 98.6 nm) and CAD-CAM (68.2± 18.1 m) groups. CAD-CAM (68.2± 18.1 m) and SLA (84.7± 27.5 m) provisionals showed comparable marginal mis-fit (p > 0.05). The mean failure load was significantly higher (p < 0.05) in CAD-CAM (687.86± 46.72 N), compared to SLA (534.8± 46.1 N) and CONV (492.7± 61.8 N) samples. Compressive strength for CAD-CAM (2.44± 0.27 MPa) samples was significantly higher (p < 0.05) than SLA (1.80± 0.15 MPa) and CONV (1.65± 0.20 MPa) groups. Marginal fit and internal adaptation of SLA printed FPDs was comparable to CAD-CAM interims. Compressive strength of the SLA interims FPDs can withstand intra-oral loads.

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