The potential of additive manufacturing technologies and their processing parameters for the fabrication of all‐ceramic crowns: A review

Abstract

Objective This article aims to provide a review of the additive manufacturing technologies and the processing parameters that have been investigated for the fabrication of all ceramic crowns. Overview Additive manufacturing has crept its way into the field of dentistry for the fabrication of resin and metal prosthesis. To evaluate the current status of additive manufacturing for the fabrication of all ceramic crowns, literature review was targeted to include publications pertaining to the fabrication of dental ceramics and all ceramic crowns. With respect to the additive manufacturing of dental ceramics, five technologies have been investigated to date: stereolithography, material extrusion, powder based fusion, direct inkjet printing, and binder jetting. The processing parameters and experimental outcomes were collated and described for each of the aforementioned technologies. Conclusion Additive manufacturing has demonstrated promising experimental outcomes and corroborated to the fabrication all ceramic crowns. However, the technology is yet to witness a commercial breakthrough within this domain. Clinical Significance Additive manufacturing mitigates raw material wastage and tooling stresses that are associated with milling of ceramics. Continued research and development can lead to its approbation as an alternate technology for manufacturing all ceramic restorations.

Ceramic Materials and Technologies Applied to Digital Works in Implant-Supported Restorative Dentistry

“…A subtractive milling machine cuts a block of restorative material to make the CAD product during the CAM phase, using cutting tools and the calculated paths of these tools. Recently, additive manufacturing technology has been introduced in various clinical dental fields and used to produce implant-supported restoration in digital works [2].…”

“…Subtractive or additive manufacturing is used to process materials, including metals, ceramics, and polymers, for implant-supported restorations [2,8]. The materials required for different CAD/CAM systems have been developed and applied in various ways, depending on the type of processing equipment involved.…”

“…Subtractive manufacturing (SM), mainly the milling method, is used for directly processing ceramic or metal ingots for definitive prostheses. In the field of implant-supported fixed prosthodontics, the ceramic materials have been actively utilized for SM, as excess material waste and esthetics limit the use of metals (including gold) [2]. SM is also applied to polymers like polymethylmethacrylate for provisional restorations.…”

“…Generally, SM produces dental prostheses accurately, and this technology has been well established in dentistry. A disadvantage is that SM leaves much waste because of a significant amount of loss of a material from milling the material block [2,8]. Another important limitation is that the degrees of freedom of the equipment, including the number of milling axes and the dimension of tools, affect the reproduction of an object, especially when the object is morphologically complex [8].…”

“…Additive manufacturing (AM) is advantageous in material waste and the reproducibility of a complex body. AM also reduces the residual stress from tooling, which frequently occurs in SM [2]. However, the dimensional accuracy, surface-finishing quality and mechanical properties of an object from AM are still under investigation in the dental field [2,8].…”