3D-printed temporal bone models for training: Does material transparency matter?

Purpose: To investigate the impact of 3D-printed temporal bone models with two different material transparencies on trainees' mastoidectomy performance.

Methods: Eleven ORL residents performed two anatomical mastoidectomies with posterior tympanotomy on two 3D-printed models with different transparency and VR simulation training. Participants where divided into two groups based on their experience.

Surface Roughness and Grain Size Variation When 3D Printing Polyamide 11 Parts Using Selective Laser Sintering.

Selective laser sintering (SLS) is a well-established technology that is used for additive manufacturing. Significant efforts have been made to improve SLS by optimizing the powder deposition, laser beam parameters, and temperature settings. The purpose is to ensure homogeneous sintering and prevent geometric and appearance inaccuracies in the manufactured objects.

3-D-Printed Models for Temporal Bone Training: A Validity Study.

Objective: 3-D printing offers convenient and low-cost mastoidectomy training; nonetheless, training benefits using 3-D-printed temporal bones remain largely unexplored. In this study, we have collected validity evidence for a low-cost, 3-D-printed temporal bone for mastoidectomy training and established a credible pass/fail score for performance on the model.

Study Design: A prospective educational study gathering validity evidence using Messick's validity framework.

3D-printing a cost-effective model for mastoidectomy training.

Background: 3D-printed temporal bone models can potentially provide a cost-effective alternative to cadaver surgery that can be manufactured locally at the training department. The objective of this study was to create a cost-effective 3D-printed model suitable for mastoidectomy training using entry level and commercially available print technologies, enabling individuals, without prior experience on 3D-printing, to manufacture their own models for basic temporal bone training.

Methods: Expert technical professionals and an experienced otosurgeon identified the best material for replicating the temporal bone and created a cost-effective printing routine for the model using entry-level print technologies.

Effect of 3D-Printed Models on Cadaveric Dissection in Temporal Bone Training.

Objective: Mastoidectomy is a cornerstone in the surgical management of middle and inner ear diseases. Unfortunately, training is challenged by insufficient access to human cadavers. Three-dimensional (3D) printing of temporal bones could alleviate this problem, but evidence on their educational effectiveness is lacking.

Enabling Micro Injection Moulding Using a Soft Tooling Process Chain with Inserts Made of Mortar Material.

The manufacturing of inserts for micro injection moulding made of mortar material is presented in this work. The fabrication of the mortar insert described in this publication relied on a versatile and relatively fast rapid prototyping process based on soft tooling. The mortar insert has a QR code with micro features on its surface, which was replicated in acrylonitrile butadiene styrene (ABS) polymer by the micro injection moulding process.

Degradation Mechanisms of Metal-Supported Solid Oxide Cells and Countermeasures: A Review.

Metal-supported oxide cells (MSCs) are considered as the third-generation solid oxide cells (SOCs) succeeding electrolyte-supported (first generation) and anode-supported (second generation) cells, which have gained much attention and progress in the past decade. The use of metal supports and advanced technical methods (such as infiltrated electrodes) has vastly improved cell performance, especially with its rapid startup ability and power density, showing a significant decrease in raw materials cost. However, new degradation mechanisms appeared, limiting the further improvement of the performance and lifetime.

3D-Printed Models for Temporal Bone Surgical Training: A Systematic Review.

Objective: 3D-printed models hold great potential for temporal bone surgical training as a supplement to cadaveric dissection. Nevertheless, critical knowledge on manufacturing remains scattered, and little is known about whether use of these models improves surgical performance. This systematic review aims to explore (1) methods used for manufacturing and (2) how educational evidence supports using 3D-printed temporal bone models.

A Soft Tooling Process Chain for Injection Molding of a 3D Component with Micro Pillars.

The purpose of this paper is to present the method of a soft tooling process chain employing Additive Manufacturing (AM) for fabrication of injection molding inserts with micro surface features. The Soft Tooling inserts are manufactured by Digital Light Processing (vat photo polymerization) using a photopolymer that can withstand relatively high temperaturea. The part manufactured here has four tines with an angle of 60°.

Studies of the interaction of two organophosphonates with nanostructured silver surfaces.

Electrochemical cycling of silver surfaces in the presence of the organophosphonates paraoxon and malathion leads to changes in the electrochemical response of silver and the formation of silver nanostructures. Adsorption of the organophosphonates onto the silver surfaces causes a significant reduction in the observed current response due to an increase in the charge transfer resistance. Surface enhanced Raman spectroscopy (SERS) measurements indicate that paraoxon adsorbs with no structural changes, while malathion decomposes and a thiophosphonate interacts with the surface.

Chemical behavior of electrochemically generated nanostructured silver surfaces.

A simple electrochemical method has been proposed for the preparation of silver nanoparticles that can be used for the detection of cyanide. Both the electrochemical behavior and morphology of the Ag nanoparticles have been characterized in the presence of KCN or diethyl cyanophosphonate (DECP) as well as in alkaline media. These were investigated by cyclic voltammetry and scanning electron microscopy (SEM).

Electrochemical properties of gas-generated silver nanoparticles in the presence of cyano- and chloride-containing compounds.

The electrochemistry of gas-generated naked Ag nanoparticles deposited on indium-tin oxide covered glass plates is compared to bulk polycrystalline Ag. The nano-specific electrochemistry has been identified and includes the preferential formation of beta-oxides. In 100 mM KOH supporting electrolyte, disruption of beta-oxide formation is exploited to test for the presence of diethyl cyanophosphonate.

Size and charge effects on the binding of CO to late transition metal clusters.

We report on the size and charge dependence of the C-O stretching frequency, nu(CO), in complexes of CO with gas phase anionic, neutral, and cationic cobalt clusters (Co(n)CO(-0+)), anionic, neutral, and cationic rhodium clusters (Rh(n)CO(-0+)), and cationic nickel clusters (Ni(n)CO(+)) for n up to 37. We develop models, based on the established vibrational spectroscopy of organometallic carbonyl compounds, to understand how cluster size and charge relate to nu(CO) in these complexes. The dominating factor is the available electron density for backdonation from the metal to the CO pi* orbital.

Substituent effects on the adsorption of dialkyl sulfides on gold nanoparticles.

The adsorption of chloroethyl ethyl sulfide and 2,2'-dichloro ethyl sulfide to gold nanoparticles has been examined in the gas phase using surface-plasmon resonance spectroscopy. The equilibrium constants for the gas-phase adsorption reactions are 14 +/- 4 and 25 +/- 5 atm(-1), respectively. The bond energy of the Au-chloroethyl ethyl sulfide complex is 44 +/- 9 kJ mol(-1).

Gold cluster carbonyls: saturated adsorption of CO on gold cluster cations, vibrational spectroscopy, and implications for their structures.

We report on the interaction of carbon monoxide with cationic gold clusters in the gas phase. Successive adsorption of CO molecules on the Au(n)(+) clusters proceeds until a cluster size specific saturation coverage is reached. Structural information for the bare gold clusters is obtained by comparing the saturation stoichiometry with the number of available equivalent sites presented by candidate structures of Au(n)(+).

Photoionization of NbCO and Nb(CO): Is CO Molecularly or Dissociatively Adsorbed on Niobium?

The photoionization efficiency spectra of gas-phase NbCO and Nb(CO) have been acquired using a laser-ablation, photoionization mass spectrometer. The adiabatic ionization energies of the species are 5.82 ± 0.

Photoinduced charge-transfer dehydrogenation in a gas-phase metal-DNA base complex: Al-cytosine.

An Al-cytosine association complex has been generated via laser ablation of a mixture of aluminum and cytosine powders that were pressed into a rod form. The ionization energy of the complex is found to be 5.16 +/- 0.