In vitro comparison of impact of different bleaching Agents on the microhardness of Enamel

Abstract

Background: Various agents are used these days for increasing the esthetics. One such procedure is bleaching that offers various advantages, as it is minimal invasive and cheap option to color the teeth and remove stain. The altered enamel after the bleaching process shows surface demineralization and porosities. The present study aimed to evaluate the effect of different bleaching agents on the microhardness of enamel. Materials and methods:A total of 100 freshly human extracted maxillary premolar teeth were selected for the study. Teeth with sound tooth structure were included for the study. All the specimens were randomly divided into four groups with 25 specimens in each group depending upon the type of bleaching agent used: Group A, artificial saliva (Control group); Group B, 35% hydrogen peroxide (HP); Group C, 25% HP; Group D, 10% carbamide peroxide (CP). Knoop Hardness Number (KHN) was calculated at 24, 48-hour, and 7-week interval.

The effects of fractional CO2 laser, Nano-hydroxyapatite and MI paste on mechanical properties of bovine enamel after bleaching

“…In our study the specimen were exposed to 40 % HP. Our findings were in accordance with the results obtained by previous studies who noticed no enamel alteration after bleaching solution exposure ( 21 , 22 ). In this study there was significant difference between 24 hours and two months and hardness was higher in two months.…”

“…It was concluded that increase in elastic modulus of bleached enamel could be achieved by post treatment. Bleaching procedures also involve different techniques with different composition of peroxides ( 21 ). Literature quotes numerous studies showing adverse effects of these agents on tooth microhardness ( 4 , 8 ).…”

“…In this study there was significant difference between 24 hours and two months and hardness was higher in two months. According to a study, there was any difference between 24, 48 hours and 1 week of bleached groups ( 21 ). Probably the use of remineralization agents leads to this difference.…”

Effects of in-office bleaching agent combined with different desensitizing agents on enamel

“…On the other hand, some studies suggest that saliva may partially lead to the replacement of the mineral loss caused by the bleaching treatment. 29 , 30 Basting, et al 31 (2005) reported that immersion in a solution similar to human saliva for two weeks after bleaching may increase microhardness of bleached enamel. Similar to previous findings, saliva could present a reformative effect on the microhardness loss in this study.…”

Reabsorción cervical externa por filtración de un material aclarante

“…liberados ( 2 ). Asimismo, se pueden presentar posibles efectos adversos al tratamiento, como la alteración del esmalte con zonas desmineralizadas, porosidades, que incluso influyen en su microdureza ( 3,4 ). Sin embargo, otros estudios mencionan que no existen alteraciones en la microdureza, la rugosidad y la morfología de la superficie ( [5][6][7] ).…”