Dimensional accuracy of 3D printed vertebra

Previous studies on accuracy of three-dimensional (3D) printed model focused on full arch measurements at few points. The aim of this study was to examine the dimensional accuracy of 3D-printed models which were teeth-prepped for three-unit fixed prostheses, especially at margin and proximal contact areas. The prepped dental model was scanned with a desktop scanner. Using this reference file, test models were fabricated by digital light processing (DLP), Multi-Jet printing (MJP), and stereo-lithography apparatus (SLA) techniques. We calculated the accuracy (trueness and precision) of 3D-printed models on 3D planes, and deviations of each measured points at buccolingual and mesiodistal planes. We also analyzed the surface roughness of resin printed models. For overall 3D analysis, MJP showed significantly higher accuracy (trueness) than DLP and SLA techniques; however, there was not any statistically significant difference on precision. For deviations on margins of molar tooth and distance to proximal contact, MJP showed significantly accurate results; however, for a premolar tooth, there was no significant difference between the groups. 3D color maps of printed models showed contraction buccolingually, and surface roughness of the models fabricated by MJP technique was observed as the lowest. The accuracy of the 3D-printed resin models by DLP, MJP, and SLA techniques showed a clinically acceptable range to use as a working model for manufacturing dental prostheses

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Dimensional Accuracy Evaluation of 3D - Printed Parts Using a 3D Scanning Surface Metrology Technique

2020 11th IEEE Control and System Graduate Research Colloquium (ICSGRC) ◽

10.1109/icsgrc49013.2020.9232583 ◽

2020 ◽

Author(s):

Emmanuelle R. Biglete ◽

Jennifer C. Dela Cruz ◽

Marvin S. Verdadero ◽

Mark Christian E. Manuel ◽

Allison R. Altea ◽

...

Keyword(s):

Dimensional Accuracy ◽

3D Scanning ◽

Surface Metrology ◽

Accuracy Evaluation ◽

3D Printed

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Quality Performance Evaluation of Thin Walled PLA 3D Printed Parts Using the Taguchi Method and Grey Relational Analysis

Journal of Manufacturing and Materials Processing ◽

10.3390/jmmp4020047 ◽

2020 ◽

Vol 4 (2) ◽

pp. 47 ◽

Cited By ~ 1

Author(s):

Kyriaki-Evangelia Aslani ◽

Dimitrios Chaidas ◽

John Kechagias ◽

Panagiotis Kyratsis ◽

Konstantinos Salonitis

Keyword(s):

Surface Roughness ◽

Wall Thickness ◽

Grey Relational Analysis ◽

Dimensional Accuracy ◽

Optimization Techniques ◽

Extraction Temperature ◽

Quality Performance ◽

Relational Analysis ◽

3D Printed ◽

Grey Relational

This paper investigates the quality performance of FDM 3D printed models with thin walls. The design of experiments method (DOE) was used and nine models of the same size were fabricated in a low-cost 3D printer using polylactic acid (PLA) material. Two limited studied parameters were considered (extraction temperature and wall thickness), each one having three levels. External X and Y dimensions were measured using a micrometer, as well as four surface roughness parameters (Ra, Rz, Rt, Rsm) with a surface tester. Two optimization techniques (the Taguchi approach and Grey relational analysis) were utilized along with statistical analysis to examine how the temperature and wall thickness affect the dimensional accuracy and the surface quality of the parts. The results showed that high extraction temperature and median wall thickness values optimize both dimensional accuracy and surface roughness, while temperature is the most important factor.

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Study the precision of fixed partial dentures of Co-Cr alloys cast over 3D printed prototypes

Archives of Materials Science and Engineering ◽

10.5604/01.3001.0012.0610 ◽

2018 ◽

Vol 1 (90) ◽

pp. 25-32 ◽

Cited By ~ 2

Author(s):

Ts. Dikova ◽

Dzh. Dzhendov ◽

Iv. Katreva ◽

Ts. Tonchev

Keyword(s):

Surface Roughness ◽

Layer Thickness ◽

Dimensional Accuracy ◽

Average Roughness ◽

Dental Clinics ◽

Primary Model ◽

3D Printers ◽

3D Printed ◽

The Right ◽

Printed Patterns

Purpose: of this paper is to investigate the accuracy of Co-Cr dental bridges, manufactured using 3D printed cast patterns. Design/methodology/approach: Four-unit dental bridges are fabricated from the alloys i-Alloy and Biosil-f by lost-wax process. The polymeric cast patterns are 3D printed with different layer’s thickness (13 μm, 35 μm and 50 μm). Two 3D printers are used: stereolithographic “Rapidshape D30” and ink-jet “Solidscape 66+”. The geometrical and fitting accuracy as well as the surface roughness are investigated. Findings: It is established that Co-Cr bridges, casted from 3D printed patterns with 50 μm layer thickness, characterize with the largest dimensions – 3.30%-9.14% larger than those of the base model. Decreasing the layer thickness leads to dimensional reduction. The dimensions of the bridges, casted on patterns with 13 μm layer thickness, are 0.17%-2.86% smaller compared to the primary model. The average roughness deviation Ra of the surface of Co-Cr bridges, manufactured using 3D printed patterns, is 3-4 times higher in comparison to the bridge-base model. The greater the layer thickness of the patterns, the higher Ra of the bridges. The silicone replica test shows 0.1-0.2 mm irregular gap between the bridge retainers and abutments of the cast patterns and Co-Cr bridges. Research limitations/implications: Highly precise prosthetic constructions, casted from 3D printed patterns, can be produced only if the specific features of the 3D printed objects are taken in consideration. Practical implications: Present research has shown that the lower the thickness of the printed layer of cast patterns, the higher the dimensional accuracy and the lower the surface roughness. Originality/value: The findings in this study will help specialist in dental clinics and laboratories to choose the right equipment and optimal technological regimes for production of cast patterns with high accuracy and low surface roughness for casting of precise dental constructions.

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Factors Influencing the Dimensional Accuracy of 3D-Printed Full-Coverage Dental Restorations Using Stereolithography Technology

The International Journal of Prosthodontics ◽

10.11607/ijp.4835 ◽

2016 ◽

Vol 29 (5) ◽

pp. 503-510 ◽

Cited By ~ 44

Author(s):

Nawal Alharbi ◽

Reham Osman ◽

Daniel Wismeijer

Keyword(s):

Dimensional Accuracy ◽

Full Coverage ◽

Dental Restorations ◽

Factors Influencing ◽

3D Printed

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Additive Manufacturing of Bone Scaffolds Using PolyJet and Stereolithography Techniques

Applied Sciences ◽

10.3390/app11167336 ◽

2021 ◽

Vol 11 (16) ◽

pp. 7336

Author(s):

Shummaila Rasheed ◽

Waqas Akbar Lughmani ◽

Muhannad Ahmed Obeidi ◽

Dermot Brabazon ◽

Inam Ul Ahad

Keyword(s):

Mechanical Properties ◽

Additive Manufacturing ◽

Dimensional Accuracy ◽

Human Bone ◽

Compression Tests ◽

3D Scaffold ◽

Bone Scaffolds ◽

3D Printed ◽

Printing Direction ◽

Printing Techniques

In this study, the printing capability of two different additive manufacturing (3D printing) techniques, namely PolyJet and micro-stereolithography (µSLA), are investigated regarding the fabrication of bone scaffolds. The 3D-printed scaffold structures are used as supports in replacing and repairing fractured bone tissue. Printed bone scaffolds with complex structures produced using additive manufacturing technology can mimic the mechanical properties of natural human bone, providing lightweight structures with modifiable porosity levels. In this study, 3D scaffold structures are designed with different combinations of architectural parameters. The dimensional accuracy, permeability, and mechanical properties of complex 3D-printed scaffold structures are analyzed to compare the advantages and drawbacks associated with the two techniques. The fluid flow rates through the 3D-printed scaffold structures are measured and Darcy’s law is applied to calculate the experimentally measured permeability. The Kozeny–Carman equation is applied for theoretical calculation of permeability. Compression tests were performed on the printed samples to observe the effects of the printing techniques on the mechanical properties of the 3D-printed scaffold structures. The effect of the printing direction on the mechanical properties of the 3D-printed scaffold structures is also analyzed. The scaffold structures printed with the µSLA printer demonstrate higher permeability and mechanical properties as compared to those printed using the PolyJet technique. It is demonstrated that both the µSLA and PolyJet printing techniques can be used to print 3D scaffold structures with controlled porosity levels, providing permeability in a similar range to human bone.

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Investigations for Wax Coated 3D Printed Hybrid Patterns for Partial Dentures

Volume 1: Additive Manufacturing; Manufacturing Equipment and Systems; Bio and Sustainable Manufacturing ◽

10.1115/msec2019-2701 ◽

2019 ◽

Author(s):

Kamaljit Singh Boparai ◽

Gurpartap Singh ◽

Rupinder Singh ◽

Sarabjit Singh

Keyword(s):

Fused Deposition Modeling ◽

Three Dimensional ◽

Surface Hardness ◽

Dimensional Accuracy ◽

Acrylonitrile Butadiene Styrene ◽

Processing Technique ◽

Patient Specific ◽

Fused Deposition ◽

3D Printed

Abstract In this work, 3D printed master patterns of acrylonitrile butadiene styrene (ABS) thermoplastic material have been used for the preparation of Ni-Cr based functional prototypes as partial dentures (PD). The study started with patient specific three dimensional (3D), CAD data (fetched through scanning). This data was used for preparation of .STL file for printing of master patterns on fused deposition modeling (FDM) setup. The 3D printed master patterns were further wax coated to reduce the surface irregularities (as cost effective post processing technique). The hybrid patterns were subjected to investment casting for the preparation of Ni-Cr based PD. The finally prepared functional prototypes as PD were optimized for dimensional accuracy, surface finish and surface hardness as responses. The results are visualized and supported by photomicrographs and in-vitro analysis.

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Research on 3D printed fixture components

MATEC Web of Conferences ◽

10.1051/matecconf/201817802008 ◽

2018 ◽

Vol 178 ◽

pp. 02008

Author(s):

Dragoş-Florin Chitariu ◽

Adriana Munteanu

Keyword(s):

Surface Roughness ◽

Fused Deposition Modeling ◽

Dimensional Accuracy ◽

Active Surface ◽

Fused Deposition ◽

Deposition Modeling ◽

3D Printed ◽

Machining Control ◽

Materials Used ◽

High Level

Fixtures are used for orientation, positioning and tightening of the workpiece during machining, control and assembly. The main fixture requirements are: orientation, positioning and tightening precision in accordance with the machining requirements. The materials used for fixture components, especially, supports and clamping mechanism are, usually, alloy steel with HRC hardness up to 55-60 HRC. These components are machined to high level of precision thus assuring the overall precision of the fixture. In order to achieve high stiffness and a good dampening capacity the fixture become, usually, very heavy. In the case of manually operated fixtures light weight is an advantage; also there are operations such as inspection, assembly where the operating forces are low. In this case lightweight materials can be used for fixture construction. In this paper the FDM (Fused Deposition Modeling) 3D printing technology is used. Support buttons and v-block fixture components were selected and 3D printed. The effect of printing orientation of active surfaces of support was analysed. The dimensional accuracy and surface roughness on the active surface were measured. Experimental results indicate that surface roughness is dependent on the orientation of the printed workpiece.

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

Revista de Chimie ◽

10.37358/rc.20.1.7866 ◽

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.

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