Mechanical properties of 3D-printed and milled composite resins for definitive restorations : an in vitro comparison of initial strength and fatigue behavior

Prause, Elisabeth (author), Malgaj, Tine (author), Kocjan, Andraž (author), Beuer, Florian (author), Hey, Jeremias (author), Jevnikar, Arne Peter (author), Schmidt, Franziska (author)

Objective: To evaluate the flexural strength and fatigue behavior of a novel 3D-printed composite resin for definitive restorations. Materials and Methods: Fifty disc-shaped specimens were manufactured from each of a nanohybrid composite resin (NHC), polymer-infiltrated ceramic network (PICN), and 3D-printed composite resin (3D) with CAD-CAM technology. Biaxial flexural strength (σ$_{in}$) (n = 30 per group) and biaxial flexural fatigue strength (σ$_{ff}$) (n = 20 per group) were measured using piston-on-three-balls method, employing a staircase approach of 105 cycles. Weibull statistics, relative-strength degradation calculations, and fractography were performed. The results were analyzed with 1-way ANOVA and Games-Howell post hoc test (α = 0.05). Results: Significant differences in σ$_{in}$ and σ$_{ff}$ among the groups (p < 0.001) were detected. The NHC group provided the highest mean ± standard deviation σ$_{in}$ and σ$_{ff}$ (237.3 ± 31.6 MPa and 141.3 ± 3.8 MPa), followed by the PICN (140.3 ± 12.9 MPa and 73.5 ± 9.9 MPa) and the 3D (83.6 ± 18.5 MPa and 37.4 ± 23.8 MPa) groups. The 3D group exhibited significantly lower Weibull modulus (m = 4.7) and up to 15% higher relative strength degradation with areas of nonhomogeneous microstructure as possible fracture origins. Conclusions: The 3D-printed composite resin exhibited the lowest mechanical properties, where areas of nonhomogeneous microstructure developed during the mixing procedure served as potential fracture origins.

• Language: English
• Keywords: 3D-printed composite resins, Weibull, additive manufacturing, flexural fatigue strength, flexural strength, milled composite resins, staircase approach
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: MF - Faculty of Medicine
• Publication status: Published
• Publication version: Version of Record
• Year: 2024
• Number of pages: Str. 391–401
• Numbering: Vol. 36, iss. 2
• PID: 20.500.12556/RUL-154085
• UDC: 616.31
• ISSN on article: 1708-8240
• DOI: 10.1111/jerd.13132
• COBISS.SI-ID: 163917571
• Publication date in RUL: 24.01.2024

Record is a part of a journal

• Title: Journal of esthetic and restorative dentistry
• Publisher: Wiley
• ISSN: 1708-8240
• COBISS.SI-ID: 3185684

Licences

• License: CC BY-NC-ND 4.0, Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International
• Link: http://creativecommons.org/licenses/by-nc-nd/4.0/
• Description: The most restrictive Creative Commons license. This only allows people to download and share the work for no commercial gain and for no other purposes.

Secondary language

• Language: Slovenian
• Keywords: 3D-natisnjene kompozitne smole, aditivna izdelava, upogibna napetost, mlete kompozitne smole

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0087
• Name: Keramični in komplementarni materiali za napredne inženirske in biomedicinske aplikacije

• Funder: ARRS - Slovenian Research Agency
• Project number: J3-3064
• Name: Predklinične in klinične raziskave cirkonijeve oksidne dentalne keramike, izdelane s tehnologijami aditivnega oblikovanja (ZIRAMDENT)