Biaxial flexural strength of hydrothermally aged resin-based materials

Autor(es)

Vivan, Rodrigo Ricci ; Piza, Mariana Miranda de Toledo ; Silva, Bruna de Mello ; Maltarollo, Thalya Fernanda Horsth ; Sivieri-Araujo, Gustavo ; Alcalde, Murilo Priori ; Duarte, Marco Antonio Hungaro ; Bonfante, Estevam Augusto ; Strazzi-Sahyon, Henrico Badaoui

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS; v. 155, p. 10-pg., 2024-05-06.

Resumo

Purpose: The strength of temporary restorations plays a vital role in full-mouth reconstruction, and it can be impacted by the aging process. The aim of this in vitro study was to evaluate the biaxial flexural strength and fractographic features of different resin-based materials submitted to thermal aging. Material and methods: One hundred and ninety-two resin disc-shaped specimens (6.5 mm in diameter and 0.5 mm in thickness) were fabricated and divided into six experimental groups according to the resin-based materials (Filtek Bulk-Fill flowable resin; J-Temp temporary resin; and Fuji Lining glass ionomer cement) and aging process (before and after thermal cycling). Biaxial flexural strength test was performed using a universal testing machine at a crosshead speed of 0.5 mm/min before and after thermal cycling (5 C-degrees and 55 C-degrees, 5760 cycles, 30 s). The mechanical properties were assessed using Weibull parameters (characteristic strength and Weibull modulus) (n = 30). Fractured specimens were examined under a polarized light stereomicroscope to identify crack origin and propagation direction. The surface microstructure of the resin-based materials was assessed by scanning electron microscopy (n = 2). The Weibull modulus (m), characteristic strength, and reliability properties were calculated, and a contour plot was used to detect differences among groups (95% confidence interval). Results: The Weibull modulus (m), characteristic strength, and reliability of the resin-based compounds were influenced by material type and thermal aging (p < 0.05). Weibull modulus (m) revealed no differences when comparing the materials and aging process (p > 0.05), except for the preceding aging period where Filtek BulkFill exhibited higher values compared to J-Temp (p < 0.05). Filtek Bulk-Fill demonstrated superior characteristic strength and reliability compared to J-Temp and Fuji Lining before and after thermal cycling (p < 0.05). Fractography of the resin-based materials showed fractures originating from surface defects exposed to tensile side and their propagation toward the compressive side. Generally, no differences in surface microstructure were observed on micrographs before and after thermal aging for Filtek Bulk-Fill and Fuji Lining. However, the aging process developed flaws in J-Temp. Conclusion: Resin-based material composition resulted in different flexural strength performance, impacting the Weibull modulus (m), characteristic strength, and reliability of the resin-based restorations. (AU)

• Processo FAPESP: 23/03089-4 - Caracterização microestrutural e óptica da zircônia (3y-tzp) reciclada e infiltrada por vidro
• Beneficiário: Bruna de Mello Silva
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 22/12118-5 - Desenvolvimento do processo de reciclagem da 3Y-TZP e aplicação na produção de compósitos com gradientes de módulo elástico
• Beneficiário: Henrico Badaoui Strazzi Sahyon
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 21/06730-7 - Rumo à zircônia sustentável reciclada a partir do descarte de usinagem e melhorada por infiltração graduada e ao desenvolvimento de blocos de zircônia multicamada resistentes, graduados, e não suscetíveis ao envelhecimento
• Beneficiário: Estevam Augusto Bonfante
• Modalidade de apoio: Auxílio à Pesquisa - Jovens Pesquisadores - Fase 2