Pietro Ausiello1, Stefano Ciaramella2, Massimo Martorelli2, Antonio Lanzotti2, Antonio Gloria3, David C Watts4. 1. School of Dentistry-University of Naples Federico II, Italy. 2. Department of Industrial Engineering, Fraunhofer JL IDEAS-University of Naples Federico II, Italy. 3. Institute of Polymers, Composites and Biomaterials-National Research Council of Italy, Naples, Italy. Electronic address: angloria@unina.it. 4. School of Medical Sciences and Photon Science Institute, University of Manchester, United Kingdom.
Abstract
OBJECTIVES: To investigate the influence of specific resin-composite, glass ceramic and glass ionomer cement (GIC) material combinations in a "multi-layer" technique to replace enamel and dentin in class II mesio-occlusal-distal (MOD) dental restorations using 3D-Finite Element Analysis (FEA). METHODS: Four 3D-FE models (A-D) of teeth, adhesively restored with different filling materials, were created and analyzed in comparison with a 3D model (E) of a sound lower molar. Models A, B & C had "multilayer" constructions, consisting of three layers: adhesive, dentin replacement and enamel replacement. Model A: had a low modulus (8GPa) composite replacing dentin and a higher modulus (12GPa) composite replacing enamel. Model B: had a GI cement replacing dentin and a higher modulus (12GPa) composite replacing enamel. Model C: had a low modulus (8GPa) composite replacing dentin and a very high modulus (70GPa) inlay replacing enamel. Model D: had a lithium disilicate inlay replacing both dentin and enamel with a luting cement base-layer. Polymerization shrinkage effects were simulated and a load of 600N was applied. All the materials were assumed to behave elastically throughout the entire deformation. RESULTS: Model A showed the highest stress distribution along all the adhesive interfaces of the shrinking resin-based materials with a critical condition and failure risk marginally and internally. Model D, by contrast, showed a more favorable performance than either of the multilayer groups (A-C). Stress and displacement plots showed an elastic response similar to that obtained for the sound tooth model. Model B and Model C performed according to their bilayer material properties. The use of a non-shrink dentin component simulating a GIC clearly affected the shrinkage stress at the basis of the Model B; while the bulk resin composite having a 12GPa Young's modulus and linear polymerization shrinkage of 1% strongly influenced the biomechanical response in the bucco-lingual direction. SIGNIFICANCE: Direct resin-based composite materials applied in multilayer techniques to large class II cavities, with or without shrinking dentin layers, produced adverse FEA stress distributions and displacements. An indirect lithium disilicate inlay used to replace lost dentin and enamel in posterior restored teeth generated lower stress levels, within the limits of the elastic FEA model. Crown
OBJECTIVES: To investigate the influence of specific resin-composite, glass ceramic and glass ionomer cement (GIC) material combinations in a "multi-layer" technique to replace enamel and dentin in class II mesio-occlusal-distal (MOD) dental restorations using 3D-Finite Element Analysis (FEA). METHODS: Four 3D-FE models (A-D) of teeth, adhesively restored with different filling materials, were created and analyzed in comparison with a 3D model (E) of a sound lower molar. Models A, B & C had "multilayer" constructions, consisting of three layers: adhesive, dentin replacement and enamel replacement. Model A: had a low modulus (8GPa) composite replacing dentin and a higher modulus (12GPa) composite replacing enamel. Model B: had a GI cement replacing dentin and a higher modulus (12GPa) composite replacing enamel. Model C: had a low modulus (8GPa) composite replacing dentin and a very high modulus (70GPa) inlay replacing enamel. Model D: had a lithium disilicate inlay replacing both dentin and enamel with a luting cement base-layer. Polymerization shrinkage effects were simulated and a load of 600N was applied. All the materials were assumed to behave elastically throughout the entire deformation. RESULTS: Model A showed the highest stress distribution along all the adhesive interfaces of the shrinking resin-based materials with a critical condition and failure risk marginally and internally. Model D, by contrast, showed a more favorable performance than either of the multilayer groups (A-C). Stress and displacement plots showed an elastic response similar to that obtained for the sound tooth model. Model B and Model C performed according to their bilayer material properties. The use of a non-shrink dentin component simulating a GIC clearly affected the shrinkage stress at the basis of the Model B; while the bulk resin composite having a 12GPa Young's modulus and linear polymerization shrinkage of 1% strongly influenced the biomechanical response in the bucco-lingual direction. SIGNIFICANCE: Direct resin-based composite materials applied in multilayer techniques to large class II cavities, with or without shrinking dentin layers, produced adverse FEA stress distributions and displacements. An indirect lithium disilicate inlay used to replace lost dentin and enamel in posterior restored teeth generated lower stress levels, within the limits of the elastic FEA model. Crown
Authors: João Paulo Mendes Tribst; Amanda Maria de Oliveira Dal Piva; Pietro Ausiello; Arianna De Benedictis; Marco Antonio Bottino; Alexandre Luiz Souto Borges Journal: Craniomaxillofac Trauma Reconstr Date: 2020-12-09
Authors: Daniel Maranha da Rocha; João Paulo Mendes Tribst; Pietro Ausiello; Amanda Maria de Oliveira Dal Piva; Milena Cerqueira da Rocha; Rebeca Di Nicoló; Alexandre Luiz Souto Borges Journal: Restor Dent Endod Date: 2019-08-07
Authors: Enrico Salvati; Cyril Besnard; Robert A Harper; Thomas Moxham; Richard M Shelton; Gabriel Landini; Alexander M Korsunsky Journal: J Adv Res Date: 2020-09-06 Impact factor: 10.479
Authors: João Paulo Mendes Tribst; Amanda Maria de Oliveira Dal Piva; Roberto Lo Giudice; Alexandre Luiz Souto Borges; Marco Antonio Bottino; Ettore Epifania; Pietro Ausiello Journal: Int J Environ Res Public Health Date: 2020-06-05 Impact factor: 3.390