|
Effects of
different concentrations of bleaching agent on the micro
hardness and shear bond strength of restorative materials –
An in vitro study
A. R. Prabhakar*, Suzan Sahana, T. Mahantesh and T. D.
Vishwas
Department of Pedodontics and Preventive Dentistry,
Bapuji Dental College and Hospital, Davangere – 577 004,
Karnataka – India.
*Corresponding author. E-mail:
attiguppeprabhakar@yahoo.com.
Tel: 91-8192-220575. Fax: 91-8192 - 220578.
Accepted
12 January, 2010 |
|
With the growing awareness of esthetics, the use of
bleaching agents are on the increase. Bleaching agents
intended to be used at home affects the existing
restorations. The aim of the present study was to evaluate
the effect of bleaching with carbamide peroxide agents at
concentrations 10 and 22% on the microhardness and shear
bond strength of composites and compomers. For microhardness
and shear bond strength evaluation, samples of both
composite and compomer restorative materials were subdivided
into control group (stored in artificial saliva),
Experimental groups bleached with 10% CP and those bleached
with 22% carbamide peroxide. Following 2 weeks of bleaching
treatment, Vickers’s hardness number was noted for each test
specimen using a microhardness meter. For shear bond
strength evaluation, the specimens were subjected to shear
test under Instron universal testing machine. One way
Analysis of Variance (ANOVA) was used for multiple group
comparisons followed by Tukey’s test for pair wise
comparison. Bleaching with carbamide ceroxide at
concentrations 10 and 22% caused reduction in hardness of
composite restorative materials. However bond strength of
both composite and a compomer restorative material was not
affected following bleaching treatment. Hence it can be
deduced that bleaching caused reduction in hardness of
composite restorative materials.
Key words:
Carbamide peroxide, bleaching, restoration, bonding,
microhardness, composite resins, compomer. |
