Thermal stresses in porcelain veneered lithium disilicate and zirconia dental crowns: comparative analysis using a validated viscoelastic finite element model - Shrestha, Rupesh; Fredeen, Steven; Reddy, Niyati; Alves, Larissa Márcia Martins; Zhang, Yu; Kim, Jeongho (Journal of the Mechanical Behavior of Biomedical Materials, 2025)