In vitro action of various carbamide peroxide gel bleaching agents on the micro hardness of human enamel.
OBJECTIVE
The study was undertaken to evaluate the effects of different carbamide peroxide based gels on micro hardness of enamel exposed to these agents for a period of 8 h daily for a total of 1 week.


METHODS
Thirty enamel specimens of 5 × 5-mm dimensions were sectioned from labial surface of maxillary incisor teeth and were embedded in Bakelite. Each block is polished to facilitate micro hardness testing. Pre-bleaching hardness values of 30 samples were measured using Vickers micro hardness tester. After exposing the specimens for different agents for 8 h daily for 1 week, post-exposure micro hardness values were taken and evaluated.


CONCLUSIONS
With increase in concentration of carbamide peroxide gel from 10% to 16%, mean micro hardness values decreased but to an insignificant level.
Department of Conservative Dentistry, SIBAR Institute of Dental Sciences, Andhra Pradesh, India.
Ch R
ChR
Sunil
V
V
Sujana
T Manisha
TM
Choudary
B
B
Nagesh