Porcelain monolayers and porcelain/alumina bilayers reinforced by Al2O3/GdAlO3 fibers


Autoria(s): Sgura, Ricardo; Medeiros, Igor Studart; Cesar, Paulo Francisco; Campos, Adeliani Almeida; Hernandes, Antonio Carlos
Contribuinte(s)

UNIVERSIDADE DE SÃO PAULO

Data(s)

24/10/2013

24/10/2013

2012

Resumo

Aim. This work tested the effect of the addition of Al2O3/GdAlO3 longitudinal fibers in different contents to veneering porcelain of two dental all ceramic systems. Methods: Fibers (0.5 mm diameter) obtained by the Laser Heated Pedestal Growth (LHPG) method were added to bar-shaped specimens made by veneer porcelain (monolayers) or both the veneer and the core ceramic (bilayers) of two all-ceramic systems: In-Ceram Alumina - glass infiltrated alumina composite (GIA) and In-Ceram 2000 AL Cubes - alumina polycrystal (AP) (VITA Zahnfabrik). The longitudinal fibers were added to veneering porcelain (VM7) in two different proportions: 10 or 17 vol%. The bars were divided into nine experimental conditions (n = 10) according to material used: VM7 porcelain monolayers, VM7/GIA, VM7/AP; and according to the amount of fibers within the porcelain layer: no fibers, 10 vol% or 17 vol%. After grinding and polishing the specimens were submitted to a three point bending test (crosshead speed = 0.5 mm/min) with porcelain positioned at tensile side. Data were analyzed by means of one-way ANOVA and a Tukey's test (alpha = 5%). Scanning electronic microscopy (SEM) was conducted for fractographic analysis. Results. Regarding the groups without fiber addition, VM7/AP showed the highest flexural strength (MPa), followed by VM7/GIA and VM7 monolayers. The addition of fibers led to a numerical increase in flexural strength for all groups. For VM7/GIA bilayers the addition of 17 vol% of fibers resulted in a significant 48% increase in the flexural strength compared to the control group. Fractographic analysis revealed that the crack initiation site was in porcelain at the tensile surface. Cracks also propagated between fibers before heading for the alumina core. Conclusions. The addition of 17 vol% of Al2O3/GdAlO3 longitudinal fibers to porcelain/glass infiltrated alumina bilayers significantly improved its flexural strength. 10 vol% or 17 vol% of fibers inclusion increased the flexural strength for all groups. (C) 2011 Elsevier Ltd. All rights reserved.

Identificador

JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS, AMSTERDAM, v. 5, n. 1, supl. 1, Part 2, pp. 110-115, JAN, 2012

1751-6161

http://www.producao.usp.br/handle/BDPI/36029

10.1016/j.jmbbm.2011.08.012

http://dx.doi.org/10.1016/j.jmbbm.2011.08.012

Idioma(s)

eng

Publicador

ELSEVIER SCIENCE BV

AMSTERDAM

Relação

JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS

Direitos

closedAccess

Copyright ELSEVIER SCIENCE BV

Palavras-Chave #DENTAL MATERIALS #DENTAL CERAMIC #MATERIALS STRENGTH #FIBER REINFORCEMENT #FIXED PARTIAL DENTURES #HEATED PEDESTAL GROWTH #FRACTURE-TOUGHNESS #MATRIX COMPOSITES #STRESS-DISTRIBUTION #EUTECTIC FIBERS #CERAMICS #STRENGTH #RUPTURE #MODE #ENGINEERING, BIOMEDICAL #MATERIALS SCIENCE, BIOMATERIALS
Tipo

article

original article

publishedVersion