Synthesis of CAD/CAM, robotics and biomaterial implant fabrication: single-step reconstruction in computer aided frontotemporal bone resection

Abstract Objective Computer-aided design and manufacturing (CAD/CAM) implants are fabricated based on volumetric analysis of computed tomography (CT) scans and are routinely used for the reconstruction of orbital fractures. We present three cases of patients with sphenoorbital meningiomas that underwent tumor resection, orbital decompression, and orbital reconstruction with patient specific porous titanium or acrylic implants in a single procedure. Methods The extent of bone resection of the sphenoorbital meningiomas was planned in a virtual three-dimensional (3D) environment using preoperative thin-layer CT data. The anatomy of the orbital wall in the resection area was reconstructed by superimposing the contralateral unaffected orbit and by using the information of the neighboring bony structures. The customized implants and a corresponding craniotomy template were designed in the desired size and shape by the manufacturer. Results All patients presented with a sphenoorbital meningioma and exophthalmos. After osteoclastic craniotomy with the drilling template, orbital decompression was performed. Implant fitting was tight in two cases and could be easily fixated with miniplates and screws. In the third patient, a reoperation was necessary for additional bone resection, as well as drilling and repositioning of the implant. The postoperative CT scans showed an accurate reconstruction of the orbital wall. After surgery, exophthalmos was substantially reduced and a satisfying cosmetic result could be finally achieved in all patients. Conclusions The concept of preoperative 3D virtual treatment planning and single-step orbital reconstruction with CAD/CAM implants after tumor resection involving the orbit is well feasible and can lead to good cosmetic results.

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Structural Analysis of Product and Computer-Aided Assembly Planning in AssemBL Software Package

Mechanical Engineering and Computer Science ◽

10.24108/0818.0001424 ◽

2018 ◽

pp. 11-33

Author(s):

A. N. Bozhko

Keyword(s):

Computer Aided Design ◽

State Of The Art ◽

Graph Model ◽

Design System ◽

Assembly Planning ◽

Complex Products ◽

Assembly Sequences ◽

Computer Aided ◽

Cad Cam ◽

Aided Design

Computer-aided design of assembly processes (Computer aided assembly planning, CAAP) of complex products is an important and urgent problem of state-of-the-art information technologies. Intensive research on CAAP has been underway since the 1980s. Meanwhile, specialized design systems were created to provide synthesis of assembly plans and product decompositions into assembly units. Such systems as ASPE, RAPID, XAP / 1, FLAPS, Archimedes, PRELEIDES, HAP, etc. can be given, as an example. These experimental developments did not get widespread use in industry, since they are based on the models of products with limited adequacy and require an expert’s active involvement in preparing initial information. The design tools for the state-of-the-art full-featured CAD/CAM systems (Siemens NX, Dassault CATIA and PTC Creo Elements / Pro), which are designed to provide CAAP, mainly take into account the geometric constraints that the design imposes on design solutions. These systems often synthesize technologically incorrect assembly sequences in which known technological heuristics are violated, for example orderliness in accuracy, consistency with the system of dimension chains, etc.An AssemBL software application package has been developed for a structured analysis of products and a synthesis of assembly plans and decompositions. The AssemBL uses a hyper-graph model of a product that correctly describes coherent and sequential assembly operations and processes. In terms of the hyper-graph model, an assembly operation is described as shrinkage of edge, an assembly plan is a sequence of shrinkages that converts a hyper-graph into the point, and a decomposition of product into assembly units is a hyper-graph partition into sub-graphs.The AssemBL solves the problem of minimizing the number of direct checks for geometric solvability when assembling complex products. This task is posed as a plus-sum two-person game of bicoloured brushing of an ordered set. In the paradigm of this model, the brushing operation is to check a certain structured fragment for solvability by collision detection methods. A rational brushing strategy minimizes the number of such checks.The package is integrated into the Siemens NX 10.0 computer-aided design system. This solution allowed us to combine specialized AssemBL tools with a developed toolkit of one of the most powerful and popular integrated CAD/CAM /CAE systems.

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Computer Aided Drafting and Manufacturing Lab Manual - CAD/CAM

SSRN Electronic Journal ◽

10.2139/ssrn.3200900 ◽

2018 ◽

Author(s):

Sathish D ◽

Veeramanikandan Murugan

Keyword(s):

Computer Aided ◽

Cad Cam

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Fracture Load of Metal, Zirconia and Polyetheretherketone Posterior CAD-CAM Milled Fixed Partial Denture Frameworks

Materials ◽

10.3390/ma14040959 ◽

2021 ◽

Vol 14 (4) ◽

pp. 959

Author(s):

Verónica Rodríguez ◽

Celia Tobar ◽

Carlos López-Suárez ◽

Jesús Peláez ◽

María J. Suárez

Keyword(s):

Computer Aided Design ◽

Testing Machine ◽

Fracture Load ◽

Fracture Pattern ◽

Bending Test ◽

Weibull Statistics ◽

Promising Alternative ◽

Computer Aided ◽

Cad Cam ◽

Group 2

The aim of this study was to investigate the load to fracture and fracture pattern of prosthetic frameworks for tooth-supported fixed partial dentures (FPDs) fabricated with different subtractive computer-aided design and computer-aided manufacturing (CAD-CAM) materials. Materials and Methods: Thirty standardized specimens with two abutments were fabricated to receive three-unit posterior FDP frameworks with an intermediate pontic. Specimens were randomly divided into three groups (n = 10 each) according to the material: group 1 (MM)—milled metal; group 2 (L)—zirconia; and group 3 (P)—Polyetheretherketone (PEEK). The specimens were thermo-cycled and subjected to a three-point bending test until fracture using a universal testing machine (cross-head speed: 1 mm/min). Axial compressive loads were applied at the central fossa of the pontics. Data analysis was made using one-way analysis of variance, Tamhane post hoc test, and Weibull statistics (α = 0.05). Results: Significant differences were observed among the groups for the fracture load (p < 0.0001). MM frameworks showed the highest fracture load values. The PEEK group registered higher fracture load values than zirconia samples. The Weibull statistics corroborated these results. The fracture pattern was different among the groups. Conclusions: Milled metal provided the highest fracture load values, followed by PEEK, and zirconia. However, all tested groups demonstrated clinically acceptable fracture load values higher than 1000 N. PEEK might be considered a promising alternative for posterior FPDs.

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Evaluation of the Feasibility of NaCaPO4-Blended Zirconia as a New CAD/CAM Material for Dental Restoration

Materials ◽

10.3390/ma14143819 ◽

2021 ◽

Vol 14 (14) ◽

pp. 3819

Author(s):

Ting-Hsun Lan ◽

Yu-Feng Chen ◽

Yen-Yun Wang ◽

Mitch M. C. Chou

Keyword(s):

Computer Aided Design ◽

Optical Microscope ◽

Dental Restoration ◽

Numerical Control ◽

Test Results ◽

Cnc Machine ◽

Computer Aided ◽

Cad Cam ◽

Aided Design ◽

Better Than

The computer-aided design/computer-aided manufacturing (CAD/CAM) fabrication technique has become one of the hottest topics in the dental field. This technology can be applied to fixed partial dentures, removable dentures, and implant prostheses. This study aimed to evaluate the feasibility of NaCaPO4-blended zirconia as a new CAD/CAM material. Eleven different proportional samples of zirconia and NaCaPO4 (xZyN) were prepared and characterized by X-ray diffractometry (XRD) and Vickers microhardness, and the milling property of these new samples was tested via a digital optical microscope. After calcination at 950 °C for 4 h, XRD results showed that the intensity of tetragonal ZrO2 gradually decreased with an increase in the content of NaCaPO4. Furthermore, with the increase in NaCaPO4 content, the sintering became more obvious, which improved the densification of the sintered body and reduced its porosity. Specimens went through milling by a computer numerical control (CNC) machine, and the marginal integrity revealed that being sintered at 1350 °C was better than being sintered at 950 °C. Moreover, 7Z3N showed better marginal fit than that of 6Z4N among thirty-six samples when sintered at 1350 °C (p < 0.05). The milling test results revealed that 7Z3N could be a new CAD/CAM material for dental restoration use in the future.

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Characterisation of the Filler Fraction in CAD/CAM Resin-Based Composites

Materials ◽

10.3390/ma14081986 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1986

Author(s):

Andreas Koenig ◽

Julius Schmidtke ◽

Leonie Schmohl ◽

Sibylle Schneider-Feyrer ◽

Martin Rosentritt ◽

...

Keyword(s):

Computer Aided Design ◽

Point Of View ◽

Specific Information ◽

Dental Resin ◽

X Ray ◽

Computer Aided ◽

Cad Cam ◽

Filler Fraction ◽

The Individual ◽

Aided Design

The performance of dental resin-based composites (RBCs) heavily depends on the characteristic properties of the individual filler fraction. As specific information regarding the properties of the filler fraction is often missing, the current study aims to characterize the filler fractions of several contemporary computer-aided design/computer-aided manufacturing (CAD/CAM) RBCs from a material science point of view. The filler fractions of seven commercially available CAD/CAM RBCs featuring different translucency variants were analysed using Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDS), Micro-X-ray Computed Tomography (µXCT), Thermogravimetric Analysis (TG) and X-ray Diffractometry (XRD). All CAD/CAM RBCs investigated included midifill hybrid type filler fractions, and the size of the individual particles was clearly larger than the individual specifications of the manufacturer. The fillers in Shofu Block HC featured a sphericity of ≈0.8, while it was <0.7 in all other RBCs. All RBCs featured only X-ray amorphous phases. However, in Lava Ultimate, zircon crystals with low crystallinity were detected. In some CAD/CAM RBCs, inhomogeneities (X-ray opaque fillers or pores) with a size <80 µm were identified, but the effects were minor in relation to the total volume (<0.01 vol.%). The characteristic parameters of the filler fraction in RBCs are essential for the interpretation of the individual material’s mechanical and optical properties.

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Influence of Sequential CAD/CAM Milling on the Fitting Accuracy of Titanium Three-Unit Fixed Dental Prostheses

Materials ◽

10.3390/ma14061401 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1401

Author(s):

Doo-Bin Song ◽

Man-So Han ◽

Si-Chul Kim ◽

Junyong Ahn ◽

Yong-Woon Im ◽

...

Keyword(s):

Titanium Alloy ◽

Computer Aided Design ◽

Dental Prostheses ◽

Computer Aided ◽

Cad Cam ◽

Fixed Dental Prostheses ◽

Gap Data ◽

Aided Design ◽

Fitting Accuracy

This study investigated the fitting accuracy of titanium alloy fixed dental prostheses (FDP) after sequential CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) fabrication. A three-unit FDP model connecting mandibular second premolars and molars was prepared and scanned to fabricate titanium FDPs by CAD/CAM milling. A total of six FDPs were sequentially milled in one titanium alloy disk using a new set of burs every time (n = 4). The fitting accuracy of FDPs was mesiodistally evaluated by a silicone replica technique and the measurement was triplicated at four different locations: MO (marginal opening), MG (marginal gap), AG (axial gap), and OG (occlusal gap). Data were statistically analyzed using ANOVA and Tukey’s HSD test. The fitting accuracy of PMMA (polymethyl methacrylate) FDPs milled using the worn or new bur were evaluated by the same procedure (n = 6). The mean dimensions of titanium FDP for all measuring positions, except for AG, were significantly increased from the third milling. However, no difference was noted between the first FDP and the second FDP milled with the same set of burs. Severe edge chippings were observed in all milling burs. Detrimental effects of the worn burs on the fitting accuracy were demonstrated in the CAD/CAM-milled PMMA FDP. The results recommend proper changing frequency of cutting burs to achieve the quality of fit and predictable outcomes for dental CAD/CAM prostheses.

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Marginal Integrity of CAD/CAM Ceramic Crowns Using Two Different Finish Line Designs

Medical Principles and Practice ◽

10.1159/000516833 ◽

2021 ◽

Author(s):

Jaber Hussain Akbar ◽

Ridwaan Omar ◽

Yacoub Al Tarakmah

Keyword(s):

Dental Treatment ◽

Statistical Significance ◽

United States Public Health ◽

Finish Line ◽

Marginal Integrity ◽

Computer Aided ◽

Cad Cam ◽

Group A ◽

Group B ◽

Line Design

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.

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Machining Feature-Based CAD/CAPP for STEP-NC

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.598.591 ◽

2014 ◽

Vol 598 ◽

pp. 591-594 ◽

Cited By ~ 2

Author(s):

Li Yan Zhang

Keyword(s):

Process Planning ◽

Manufacturing Process ◽

Data Transfer ◽

Operation Planning ◽

Computer Aided Process Planning ◽

Machining Feature ◽

Computer Aided ◽

Cad Cam ◽

Feature Based ◽

Cam Systems

ISO 14649, known as STEP-NC, is new model of data transfer between CAD/CAM systems and CNC machines. In this paper, the modeling based on machining feature is proposed. The machining feature comes from the manufacturing process considering the restriction of machining technology and machining resource. Then the framework for computer aided process planning is presented, where the algorithms of operation planning is studied. The practical example has been provided and results indicate that machining feature based model can integrate with CAPP and STEP-NC seamlessly.

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