Publications by authors named "Guilherme Siqueira Ferreira Anzaloni Saavedra"
Objective: The aim of this study was to evaluate the effect of four different finishing procedures on the fatigue strength of a fully stabilized zirconia (5Y-FSZ) material.
Materials And Methods: Disc-shaped specimens of a 5Y-FSZ (Katana UTML, Kuraray Noritake) were made (ISO 6872-2015), grinded with 600- and 1200-grit silicon carbide paper, sintered as recommended, and randomly assigned into four groups according to the finishing technique: C (control, as-sintered), P (polished with polishing rubbers), G (glaze application - powder/liquid technique), and PG (polished with polishing rubbers + glaze application - powder/liquid). Then fatigue strength (staircase method), X-ray diffraction (XRD), and scanning electron microscopy (SEM) analyses were performed.
Prefabricated glass fiber-reinforced composite posts have been widely used because of their esthetic properties and favorable biomechanical behavior; however, because they are prefabricated, they may not adapt to the anatomy of all root canals. This case report describes a procedure for restoring teeth with a custom, 1-piece, fiber-reinforced composite post and core fabricated using computer-aided design/computer-aided manufacturing (CAD/CAM). The excellent adaptation of this custom endodontic post enables the use of a thinner, homogenous cement layer; in addition, it eliminates the need to construct a composite resin core build-up.
View Article and Find Full Text PDFDoes overlay preparation design affect polymerization shrinkage stress distribution? A 3D FEA study.
Comput Methods Biomech Biomed Engin
July 2021
Article Synopsis
- The study investigates the polymerization shrinkage stress of three types of dental preparation designs for indirect ceramic overlays using finite element analysis.
- Results indicated that the isthmus preparation (IST) had the highest stress levels followed by without isthmus (wIST) and non-retentive (nRET) preparations, with significant differences noted in both the cement layer and the tooth structure.
- The non-retentive preparation (nRET) demonstrated the lowest shrinkage stress and a more uniform stress distribution, suggesting that this design may be more advantageous for reducing stress on dental materials.
Impact of crystallization firing process on the microstructure and flexural strength of zirconia-reinforced lithium silicate glass-ceramics.
Dent Mater
October 2018
Objectives: The aim of this study was to characterize the microstructure of two zirconia-reinforced lithium silicate (ZLS) glass-ceramics and evaluate their mechanical properties before and after the crystallization firing process (CFP).
Methods: Field emission-scanning electron microscope (FE-SEM) and energy-dispersive X-ray spectroscopy (EDS) analyses were performed for microstructural characterization. To evaluate the pattern of crystallization and the molecular composition of ZLS glass-ceramics, was used X-ray diffraction (XRD).
Purpose: To evaluate the flexural strength of two fixed dental prosthesis (FDP) designs simulating frameworks of adhesive fixed partial prostheses, reinforced or not by glass fiber.
Materials And Methods: Forty specimens, made with composite resin, were divided into 4 groups according to the framework design and the presence of fiber reinforcement: A1 - occlusal support; A2: occlusal support + glass fiber; B1: occlusal and proximal supports; B2: occlusal and proximal supports + glass fiber. The specimens were subjected to the three-point bending test, and the data were submitted to two-way ANOVA and Tukey's test (5%).