Disinfection procedures: their effect on the dimensional accuracy and surface quality of irreversible hydrocolloid impression materials and gypsum casts

Purpose This paper aims to investigate the quality of printed surfaces and manufacturing tolerances by comparing the cylindrical cavities machined in parts obtained by fused deposition modeling (FDM) with the holes manufactured during the printing process itself. The comparison focuses on the results of roughness and tolerances, intending to obtain practical references when making assemblies. Design/methodology/approach The experimental approach focuses on the comparison of the results of roughness and tolerances of two manufacturing strategies: geometric volumes with a through-hole and the through-hole machined in volumes that were initially printed without the hole. Throughout the study, both alternates are explained to make appropriate recommendations. Findings The study shows the best combinations of technological parameters, both machining and three-dimensional printing, which have been decisive for obtaining successful results. These conclusive results allow enunciating recommendations for use in the industrial environment. Originality/value This paper fulfills an identified need to study the dimensional accuracy of the geometries obtained by additive manufacturing, as no experimental evidence has been found of studies that directly address the problem of the FDM-printed part with geometric and dimensional tolerances and desirable surface quality for assembly.

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Comparison of the dimensional accuracy of a combined reversible/irreversible hydrocolloid impression system with other commonly used impression materials

Journal of Prosthetic Dentistry ◽

10.1016/s0022-3913(84)80006-2 ◽

1984 ◽

Vol 52 (6) ◽

pp. 795-799 ◽

Cited By ~ 7

Author(s):

H.W. Herring ◽

M.A. Tames ◽

L.D. Zardiackas

Keyword(s):

Dimensional Accuracy ◽

Impression Materials ◽

Irreversible Hydrocolloid

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Scratching Experimental Research on Critical Cut Depth of Glass BK7

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.589-590.194 ◽

2013 ◽

Vol 589-590 ◽

pp. 194-197 ◽

Cited By ~ 1

Author(s):

Peng Jia

Keyword(s):

Surface Quality ◽

Optical Glass ◽

Dimensional Accuracy ◽

Cutting Fluid ◽

Dry Cutting ◽

Diamond Cutting ◽

Fluid Properties ◽

Indentation Experiment ◽

Cut Depth

For the technology of diamond cutting of optical glass, the machinability of glass is poor, which hindering the practical application of this technology. In order to investigate and ameliorate the machinability of glass, and achieve optical parts with the satisfied surface quality and dimensional accuracy, this paper first conducted SF6 indentation experiment by Vickers microhardness instrument, and then the scratching tests with increasing depths of cut were conducted on glass SF6 to evaluate the influence of the cutting fluid properties on the machinability of glass. Based on this, turning tests were carried out, and the surface quality of SF6 was assessed based on the detections of the machined surfaces roughness. Experimental results indicated that compared with the process of dry cutting, the machinability of glass SF6 can be improved by using the cutting fluid

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The effect of pouring time on the dimensional accuracy of casts made from different irreversible hydrocolloid impression materials

Contemporary Clinical Dentistry ◽

10.4103/0976-237x.118368 ◽

2013 ◽

Vol 4 (3) ◽

pp. 313 ◽

Cited By ~ 7

Author(s):

SupneetSingh Wadhwa ◽

Richa Mehta ◽

Nidhi Duggal ◽

Kamlesh Vasudeva

Keyword(s):

Dimensional Accuracy ◽

Impression Materials ◽

Irreversible Hydrocolloid

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Combination of Laser Material Deposition and Laser Surface processes for the manufacture of sculptured surface components

10.20944/preprints201806.0450.v1 ◽

2018 ◽

Author(s):

Jon Iñaki Arrizubieta ◽

Magdalena Cortina ◽

Jose Exequiel Ruiz ◽

Aitzol Lamikiz

Keyword(s):

Surface Quality ◽

Dimensional Accuracy ◽

Laser Machining ◽

Additive Process ◽

Laser Polishing ◽

Material Deposition ◽

Laser Heat Source ◽

Near Net Shape ◽

Machining Operations

The present work proposes a novel manufacturing technique based on the combination of Laser Metal Deposition, Laser Beam Machining and Laser Polishing processes for the complete manufacturing of complex parts. Therefore, the complete process is based on the application of a laser heat source both for the building of the preform shape of the part by additive manufacturing and for the finishing operations. Their combination enables to manufacture near-net-shape parts and afterwards, remove the excess material via laser machining, which has resulted to be capable of eliminating the waviness resulting from the additive process. Besides, surface quality is improved via laser polishing to reduce the roughness of the final part. Therefore, conventional machining operations are eliminated, what results in a much cleaner process. In order to validate the capability of this new approach, the dimensional accuracy and surface quality of the resulting parts are evaluated. The process has been validated on an Inconel 718 test part, where a previously additively built up part has been finished by means of laser machining and laser polishing.

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Implant Impression Making: Take-Off Guide for Beginners

Dental Journal of Advance Studies ◽

10.1055/s-0041-1736489 ◽

2021 ◽

Author(s):

Aaina Dhanda ◽

Tarun Kalra ◽

Manjit Kumar ◽

Ajay Bansal ◽

Ruchi Sharma

Keyword(s):

Computer Aided Design ◽

Dimensional Accuracy ◽

Computer Assisted ◽

Impression Materials ◽

Starting Point ◽

Irreversible Hydrocolloid ◽

Passive Fit ◽

Edentulous Patients ◽

Aided Design ◽

Relationship Of

AbstractDental implants are fixtures that constitute for the replacements of the root of a missing natural tooth. Dental implant therapy has been widely used for the restoration of partially and fully edentulous patients. The implant literature emphasizes the importance of a passively fitting prosthesis to prevent prosthodontic complications or even loss of fixture integration. Failure to achieve a passively fitting prosthesis and force tightening of superstructure may result in complications such as abutment, framework, and gold screw loosening or fracture. Various materials that can be used for making an implant impression are polyether, polyvinylsiloxane, condensation silicone, polysulfide, irreversible hydrocolloid material, and various others. There are various studies in relation to the accuracy of these impression materials out of which various scientists concluded different results with most studies stating polyether with the maximum amount of dimensional accuracy in comparison to other materials. An accurate implant impression plays a significant role and serves as a starting point in the process of producing good working casts. Thus, the accuracy of impression techniques becomes a significant issue in consideration of passive fit. Reproduction of intraoral relationship of implants through impression procedures is the first step in achieving accurate fit prosthesis. This transference is still complicated by the number, angulation, depth, and position of implants. The advent of computer-aided design/computer-assisted manufacturing technology improved the framework fabrication procedures and has increased the precision of fit of implant prosthesis.

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