Microstructural Observations of Laser-Sintered Specimens for Prosthodontic Applications
type: CreativeWork
description: ABSTRACTObjectives: Laser sintering is a recently introduced technology that has been used to prepare dental restorations from a biocompatible Co-Cr base metal alloy. The objectives of this study were to obtain detailed information about dimensional accuracy available with laser sintering, along with the microstructure and Vickers hardness of the alloy.Methods: Representative maxillary coping and implant framework specimens were prepared from STL files by a commercial laser sintering apparatus (Phenix Systems), using the dedicated Co-Cr alloy. Compatible dental porcelain was bonded to the coping specimen (North Shore Dental Labs, Lynn, MA). Specimens were sectioned with a slow-speed diamond saw, prepared for metallographic examination by resin-mounting and polishing with a series of abrasives, and observed with a scanning electron microscope and optical microscope at a range of magnifications. Alloy compositions were obtained by x-ray energy-dispersive spectrometric analyses. A Co-Cr alloy implant framework prepared by conventional milling/polishing and a cast Ni-Cr alloy coping for a conventional metal-ceramic restoration with the dental porcelain served as controls. Microstructures of the laser-sintered and cast alloys were revealed by electrolytic etching. Values of Vickers hardness for the Co-Cr alloy in the laser-sintered implant framework and the coping for the metal-ceramic restoration were compared, along with the cast coping. Dimensions of the milled/polished and laser-sintered implant frameworks were measured microscopically and compared.Results: The laser-sintered Co-Cr alloy had a fine-grained microstructure, and there was some difficulty in revealing full details by electrolytic etching, whereas the cast Ni-Cr alloy had a well-defined dendritic microstructure. The laser-sintered Co-Co alloy coping had intimate interfacial attachment to dental porcelain. The Vickers hardness was slightly (< 10%, but statistically significant), higher for the laser-sinter…
abstract: ABSTRACTObjectives: Laser sintering is a recently introduced technology that has been used to prepare dental restorations from a biocompatible Co-Cr base metal alloy. The objectives of this study were to obtain detailed information about dimensional accuracy available with laser sintering, along with the microstructure and Vickers hardness of the alloy.Methods: Representative maxillary coping and implant framework specimens were prepared from STL files by a commercial laser sintering apparatus (Phenix Systems), using the dedicated Co-Cr alloy. Compatible dental porcelain was bonded to the coping specimen (North Shore Dental Labs, Lynn, MA). Specimens were sectioned with a slow-speed diamond saw, prepared for metallographic examination by resin-mounting and polishing with a series of abrasives, and observed with a scanning electron microscope and optical microscope at a range of magnifications. Alloy compositions were obtained by x-ray energy-dispersive spectrometric analyses. A Co-Cr alloy implant framework prepared by conventional milling/polishing and a cast Ni-Cr alloy coping for a conventional metal-ceramic restoration with the dental porcelain served as controls. Microstructures of the laser-sintered and cast alloys were revealed by electrolytic etching. Values of Vickers hardness for the Co-Cr alloy in the laser-sintered implant framework and the coping for the metal-ceramic restoration were compared, along with the cast coping. Dimensions of the milled/polished and laser-sintered implant frameworks were measured microscopically and compared.Results: The laser-sintered Co-Cr alloy had a fine-grained microstructure, and there was some difficulty in revealing full details by electrolytic etching, whereas the cast Ni-Cr alloy had a well-defined dendritic microstructure. The laser-sintered Co-Co alloy coping had intimate interfacial attachment to dental porcelain. The Vickers hardness was slightly (< 10%, but statistically significant), higher for the laser-sinter…
author: Fathalah, Ahmed A.A
language: English
keywords: Dentistry, Laser sintering, Alloys, Prosthodontics, Hardness, Composition, Metals, Structure
date published: 2013-08-23
date modified: 2026-07-24T03:37:46Z
provider: OhioLINK
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: The Ohio State University