Additive manufacturing trueness and internal fit of crowns in resin modified with a commercially available ceramic composite concentrate

Gabriela Panca Sabatini; Mustafa Borga Dönmez; Gülce Çakmak; Münir Demirel; Nadin Al-Haj Husain; Newton Sesma; Hyung-In Yoon; Burak Yilmaz

doi:10.1016/j.prosdent.2024.09.005

Additive manufacturing trueness and internal fit of crowns in resin modified with a commercially available ceramic composite concentrate

J Prosthet Dent. 2024 Sep 19:S0022-3913(24)00603-6. doi: 10.1016/j.prosdent.2024.09.005. Online ahead of print.

Authors

Gabriela Panca Sabatini¹, Mustafa Borga Dönmez², Gülce Çakmak³, Münir Demirel⁴, Nadin Al-Haj Husain⁵, Newton Sesma⁶, Hyung-In Yoon⁷, Burak Yilmaz⁸

Affiliations

¹ Clinical Assistant, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland; and PhD candidate, Department of Prosthodontics, School of Dentistry, University of São Paulo (USP), São Paulo, Brazil.
² Associate Professor, Department of Prosthodontics, Faculty of Dentistry, Biruni University, Istanbul, Turkey; and PhD Student, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland. Electronic address: mustafa-borga.doenmez@unibe.ch.
³ Senior Research Associate, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
⁴ Assistant Professor, Department of Prosthodontics, Faculty of Dentistry, Biruni University, Istanbul, Turkey.
⁵ Senior Lecturer, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
⁶ Associate Professor, Department of Prosthodontics, School of Dentistry, University of São Paulo (USP), São Paulo, Brazil.
⁷ Associate Professor, Department of Prosthodontics, School of Dentistry and Dental Research Institute, Seoul National University, Seoul, Republic of Korea; and Adjunct Professor, Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, Bern, Switzerland.
⁸ 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: 39304488
DOI: 10.1016/j.prosdent.2024.09.005

Abstract

Statement of problem: Inorganic fillers can be incorporated into additively manufactured (AM) resins to improve their properties, and a ceramic composite concentrate has been recently marketed for this purpose. However, knowledge on the printability of AM resins modified with this concentrate is lacking.

Purpose: The purpose of this in vitro study was to evaluate the manufacturing trueness and internal fit of AM crowns in a dental resin modified with a commercially available ceramic composite concentrate.

Material and methods: A maxillary right first molar typodont tooth was prepared and digitized to design a crown in standard tessellation language (STL) format. This STL file was used to fabricate a total of 30 AM crowns, 10 with a resin with no fillers for interim restorations (AM-I), 10 AM-I resin incorporated with ceramic composite concentrate (AM-IR), and 10 with a ceramic-filled resin intended for definitive restorations (AM-D). The modification of the AM-IR resin was performed by mechanically mixing 30 wt% of a commercially available ceramic composite concentrate into AM-I. An intraoral scanner was used to digitize all crowns, which were then seated on the prepared typodont abutment and rescanned. The manufacturing trueness of each crown was measured in 4 regions (overall, external, intaglio, and marginal) and reported with root mean square (RMS) estimates. The internal gaps were calculated by using a triple scan protocol. The intaglio surface deviations were assessed with the Kruskal-Wallis and Dunn tests, while the remaining data were analyzed with the 1-way analysis of variance and Tukey honestly significant difference tests (α=.05).

Results: AM-IR had the highest overall and external RMS and had higher intaglio RMS than AM-D (P≤.001). AM-I had the lowest marginal RMS (P≤.002). AM-IR had the highest average gap values (P≤.027).

Conclusions: AM-IR crowns mostly had lower trueness and high internal gaps. However, the differences among the tested materials in fabrication trueness and average gap values were small, and internal gaps were within the previously reported thresholds.