Wear behavior of materials for additive manufacturing after simulated occlusion of deciduous dentition

• Published in: Journal of the mechanical behavior of biomedical materials Vol. 138; p. 105627
• Main Authors: Shin, Yujeong, Wada, Kanae, Tsuchida, Yumi, Ijbara, Manhal, Ikeda, Masaomi, Takahashi, Hidekazu, Iwamoto, Tsutomu
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01-02-2023
• Subjects: 3D printing; Additive manufacturing; Deciduous teeth; Dental enamel; Dental materials; Dental Porcelain; Materials Testing; Mechanical Phenomena; Microscopy, Electron, Scanning; Surface Properties; Tooth, Deciduous; Wear; Deciduous teeth; Dental materials; Dental enamel; Additive manufacturing; Wear; 3D printing
• ISSN: 1751-6161; 1878-0180
• DOI: 10.1016/j.jmbbm.2022.105627

To evaluate wear characteristics of materials for additive manufacturing (AM) after a simulated occlusal test in primary teeth. Wear was simulated by means of impacting - sliding wear testing (ISWT) between specimens prepared from materials for AM against enamel derived from deciduous teeth.
The prepared hemispherical upper specimens were subjected to impacting-sliding wear test (ISWT) machine against the flattened enamel of deciduous molars on lower specimens. The samples were subjected to 20,000 load cycles using a contact force of 30 N between the opposing surfaces under controlled conditions. In the upper specimens, five groups (n=9): four types of additively manufactured materials Dima, Zenith, Detax, Veltz and a deciduous enamel groups were tested in this study. The enamel-to-enamel group was used as the control. Wear characteristics comprised wear surface area, wear depth, wear volumetric loss, and surface roughness were measured with a confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Data obtained were statistically analyzed by Kruskal-Wallis test and Dunn’s test with Bonferroni correction (p < 0.05).
Dima showed significantly higher worn surface area (p = 0.009, 0.001, and < 0.001 for Zenith, Detax, and control enamel, respectively), volumetric loss (p = 0.027, 0.007, and < 0.001 for Zenith, Detax, and control enamel, respectively), and damaged opposing enamel (p = 0.002, 0.001, and 0.01 for Detax, Veltz, and control enamel, respectively). There was no significant difference among the volumetric loss in Zenith and Detax. However, SEM revealed that Zenith showed rough worn surfaces and chipping, Detax showed rather a smooth circular worn surface. The worn area of Veltz was smaller than Detax and Zenith at 5,000 cycles, but higher at 15,000 and 20,000 cycles, and SEM showed detachment.
Wear behavior was different among different materials for AM. In the upper specimens, DM and VZ showed large wear. In the lower specimens, DM caused largest enamel wear and damage. In contrast, ZT and DX showed lower wear and caused less damage to the antagonistic primary enamel. SEM image of ZT showed large losses due to chipping, whereas DX showed the rather smooth. DX was confirmed to have lowest wear and caused least damage to the opposing deciduous enamel, which might be applicable as restorative treatments in deciduous dentition.
Additive manufactured dental materials could be considered as a treatment modality in deciduous teeth.
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•Four additive manufacturing materials opposed by the enamel of deciduous molars were evaluated the wear characteristics.•Wear characteristics of materials for additive manufacturing were compared with deciduous enamel-enamel.•Detax and Zenith are promising as restorative options in deciduous teeth.•Additive manufactured dental materials could be considered as a treatment modality in deciduous teeth.