Tooth-Colored CAD/CAM Materials for Application in 3-Unit Fixed Dental Prostheses in the Molar Area: An Illustrated Clinical Comparison

Abstract

The aim of this study was to compare the clinical properties of tooth-colored computer-aided design/computer-aided manufacturing (CAD/CAM) materials for the fabrication of a 3-unit fixed dental prostheses (FDPs) in the same clinical scenario. A 53-year-old female patient was supplied with a 3-unit FDP to replace a second premolar in the upper jaw. Restorations were fabricated from 3 mol%, 4 mol%, and 5 mol% yttrium oxide zirconia, zirconia with translucency gradient, indirect composite resin, polyetheretherketone (PEEK), and polyetherketoneketone (PEKK). Milling time, weight, and radiopacity were investigated. Esthetics were examined following the US Public Health Service criteria (USPHS). The milling time for zirconia was twice as high as for the indirect composite resin, PEEK, or PEKK. The latter materials had a weight of 2 g each, while zirconia restorations yielded 5 g. Zirconia presented intense radiopacity. PEEK and PEKK required veneering and an opaquer was applied to the PEKK framework. All FDPs showed acceptable esthetics. PEEK and PEKK restorations were featured by a grayish shimmering. A variety of CAD/CAM materials are available to fabricate 3-unit FDPs with esthetically acceptable results. In the esthetic zone, PEEK and PEKK require veneering and an opaquer might be applied. Milling time, weight, and radiopacity were relatively high for zirconia FDPs.

Influence of Polymeric Restorative Materials on the Stress Distribution in Posterior Fixed Partial Dentures: 3D Finite Element Analysis

“…The authors observed that three-unit FDPs manufactured from prepressed PEEK presented greater deformation and required higher loads (2354 N) to fracture when compared to the pressed ones in granular form (1738 N). Some studies report that PEEK is considered a suitable material for restorations in load-bearing occlusal areas [46][47][48][49][50]. However, due to the material elastic modulus, PEEK can be comparable with a temporary material [50].…”

Influence of Alternative and Conventional Surface Treatments on the Bonding Mechanism between PEEK and Veneering Resin for Dental Application

“…Although the weight of the prosthesis does not represent a problem per se [18] regarding this last indication, a reduction in the prosthesis volume into the palatal defect by an implant-retained obturator and its higher stability can be considered a gain in the patient's quality of life [19]. Nevertheless, PEEK infrastructures should be veneered by lithium disilicate, veneering resins for laboratory use or polymethylmethacrylate to achieve desirable aesthetic requirements [20]. The bond strength between the veneering material and PEEK infrastructure must be strong enough to resist the adverse buccal environment which is subject to cyclic loading, different temperatures, and moisture [21].…”

Effect of Acid-Etching Duration on the Adhesive Performance of Printed Polyetheretherketone to Veneering Resin

“…Polyetheretherketone (PEEK), a high-performance polymeric material successfully utilized in traditional industrial fields, has been gradually introduced into dentistry and applied as a framework material of complete dentures, removable partial dentures, and implant-supported prostheses [1][2][3]. Compared with existing dental materials, PEEK shows better mechanical properties of flexural strength and fracture resistance [4,5]. Most reported PEEK prostheses were fabricated with the CAD/CAM milling technique, while the cost of excess material and time remain to be solved in the future [5][6][7].…”

“…Compared with existing dental materials, PEEK shows better mechanical properties of flexural strength and fracture resistance [4,5]. Most reported PEEK prostheses were fabricated with the CAD/CAM milling technique, while the cost of excess material and time remain to be solved in the future [5][6][7]. Additive manufacturing, also named 3D printing, offers a remarkable utilization rate of the material and good shape ability, which has attracted the focus of researchers [8,9].…”

“…Pigments including TiO 2 powders were filled into PEEK to improve the unfavorable color of pure PEEK for clinical use, while this color-modified PEEK hardly improved the aesthetic demand [12]. Explorations achieved good effects by coating veneering resin onto the PEEK surface [5,13,14]. PEEK, as an inert material, has limited bonding strength compared to conventional adhesives.…”