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, 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)