Comparison of trueness and margin quality of additively and subtractively manufactured definitive resin-based laminate veneers

Deniz Yılmaz; Gülce Çakmak; Mehmet Esad Güven; Hyung-In Yoon; Martin Schimmel; Burak Yilmaz

doi:10.1016/j.prosdent.2023.09.011

Comparison of trueness and margin quality of additively and subtractively manufactured definitive resin-based laminate veneers

J Prosthet Dent. 2023 Oct 27:S0022-3913(23)00625-X. doi: 10.1016/j.prosdent.2023.09.011. Online ahead of print.

Authors

Deniz Yılmaz¹, Gülce Çakmak², Mehmet Esad Güven³, Hyung-In Yoon⁴, Martin Schimmel⁵, Burak Yilmaz⁶

Affiliations

¹ Lecturer, Department of Prosthodontics, Faculty of Dentistry, Alanya Alaaddin Keykubat University, Antalya, Turkey.
² Senior Research Associate, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland. Electronic address: guelce.cakmak@unibe.ch.
³ Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Necmettin Erbakan University, Konya, Turkey.
⁴ Associate Professor, Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea; and Visiting Professor, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
⁵ Professor and Head, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland; and External Research Associate, Division of Gerodontology and Removable Prosthodontics, University Clinics of Dental Medicine, University of Geneva, Geneva, Switzerland.
⁶ Associate Professor, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland; Associate Professor, Department of Restorative, Preventive, and Pediatric Dentistry, School of Dental Medicine, University of Bern, Bern, Switzerland; and Adjunct Professor, Division of Restorative and Prosthetic Dentistry, The Ohio State University, Columbus, Ohio.

PMID: 39492045
DOI: 10.1016/j.prosdent.2023.09.011

Abstract

Statement of problem: Currently available 3-dimensional (3D) additively manufactured (AM) resins used for definitive restorations have different chemical compositions and viscosities. The fabrication trueness and margin quality of laminate veneers additively manufactured with different resins have not been extensively studied.

Purpose: The purpose of this in vitro study was to evaluate the fabrication trueness and margin quality of AM and subtractively manufactured (SM) definitive resin-based laminate veneers.

Material and methods: A laminate veneer restoration for a maxillary right central incisor with a 25-µm cement space was designed to generate a reference laminate veneer standard tessellation language (STL) file (RLV-STL). This RLV-STL was used to fabricate resin-based laminate veneers (N=60) for definitive use, either using AM (a low-viscosity, urethane acrylate-based resin (C&B Permanent, AM-LV), a high-viscosity, urethane acrylate-based resin (Tera Harz TC-80DP, AM-HV), and a glass-reinforced composite resin (Crowntec, AM-S) or SM (glass-filler reinforced composite resin blocks (Tetric CAD, SM) technologies. All laminate veneers were digitized with an intraoral scanner (CEREC Primescan SW 5.2) to generate their test STL files (TLV-STLs). RLV-STL and TLV-STLs were transferred into a 3D analysis software program (Geomagic Control X), and a trueness (external, intaglio, and marginal surface) analysis was performed by using the root mean square (RMS) method. The margin quality of laminate veneers was examined visually under a stereomicroscope and graded. The Kruskal-Wallis and Dunn tests were performed to analyze the data (α=.05).

Results: External, intaglio, and marginal RMS values showed statistically significant differences among test groups (P<.001). The SM group had the highest RMS values for the external surface (P<.001), whereas the AM-LV group had the lowest RMS values. The AM-HV group had the highest RMS values for the intaglio surface (P<.001). No significant difference was found between the SM and AM-HV groups for marginal RMS values, which were higher than for the other groups (P=.830). All average values for the axial mesial, axial distal, and incisal edge margin quality of laminate veneers were found to be similar and Grade 3 (smooth edge) in all groups.

Conclusions: Regardless of the evaluated surface, the fabrication technique affected the trueness of laminate veneers. The low-viscosity AM laminate veneers and AM laminate veneers reinforced with glass fillers had higher trueness than the SM laminate veneers at all surfaces. The low-viscosity AM laminate veneers had the highest trueness on external and marginal surfaces among the test groups and had higher trueness than the high-viscosity AM laminate veneers.