The results of this meta- analysis showed no significant changes in enamel microhardness when using the 10 % carbamide peroxide bleaching gel over periods of 7 , 14 and 21 days
Several studies have investigated the effect of bleaching on dental tissues .
The evaluation of the effect of home bleaching with 10 % carbamide peroxide is important for assessing alterations in enamel microhardness that may affect dental health in terms of resistance to masticatory forces .
This meta- analysis was performed in order to determine scientific evidence regarding the effects of home vital bleaching with 10 % carbamide peroxide gel on the microhardness of human dental enamel .
In-Vitro Comparative Study of In-office and Home Bleaching Agents on Surface Micro-morphology of Enamel.
OBJECTIVE To evaluate the effect of home-use bleaching agent containing 16 % Carbamide Peroxide ( CP ) and in-office bleaching agent with 38 % Hydrogen Peroxide ( HP ) on surface micro-morphology of enamel . STUDY DESIGN An experimental study . PLACE AND DURATION OF STUDY The discs were prepared at Material Engineering Department of NED University of Engineering and Technology , Karachi , and surface morphology was analyzed at Central ized Science Laboratory of Karachi University , Pakistan . Duration of study was one year from January to December 2012 . METHODOLOGY Forty five sound human third molar crowns , extracted for periodontal reason , were included in the study .  Longitudinal sections were made using diamond disks ( 0.2 mm ) under water lubrication to obtain enamel slabs measuring ( 3 mm x 3 mm ) . The slabs were embedded in polystyrene resin by using 2.0 cm diameter PVC molds , leaving the outer enamel surface uncovered by the resin . Ninety dental enamel slabs were prepared . The slabs were then r and omly divided into 3 groups . Each group contained thirty specimens ( n=30 ) . Group 1 was kept in artificial saliva at 37 ° C in incubator ( Memart , Germany ) during whole experiment . Group 2 was treated with power whitening gel ( White Smile 2011 , Germany ) . Group 3 was treated with tooth whitening pen ( White Smile 2011 , Germany ) . The most central region or the region that was most representative of the entire surface area was used . The SEM ( Jeol-Japan-JSM6380A , JAPAN ) micrographs were examined to determine the type of surface presented . The enamel changes were classified as no or mild alteration , moderate alteration and severe altered surface . RESULTS Regarding micro-morphology , the enamel surface of control groups showed smooth surface in general with some scattered clear scratches due to the polishing procedure . The specimens bleached in group 2 and group 3 , represented areas of mild erosion . CONCLUSION Bleaching with 38 % Hydrogen Peroxide ( HP ) and 16 % Carbamide Peroxide ( CP ) result ed in mild changes in surface micro-morphology of enamel
The results of this meta- analysis showed no significant changes in enamel microhardness when using the 10 % carbamide peroxide bleaching gel over periods of 7 , 14 and 21 days
Several studies have investigated the effect of bleaching on dental tissues .
The evaluation of the effect of home bleaching with 10 % carbamide peroxide is important for assessing alterations in enamel microhardness that may affect dental health in terms of resistance to masticatory forces .
This meta- analysis was performed in order to determine scientific evidence regarding the effects of home vital bleaching with 10 % carbamide peroxide gel on the microhardness of human dental enamel .