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Microhardness Measurements on Tooth and Alveolar Bone in Rodent Oral Disease Models
Published on: April 26, 2024
Effect of four different opalescence tooth-whitening products on enamel microhardness
A Majeed1, S R Grobler, M H Moola
1Oral and Dental Research Institute, Faculty of Dentistry, University of the Western Cape, Tygerberg, South Africa.
Objectives:
The purpose was to evaluate the effect of various Opalescence tooth-whitening products on enamel.
Methods And Materials:
Enamel blocks were exposed to Opalescence PF 10% Carbamide Peroxide (n = 10), Opalescence PF 20% Carbamide Peroxide (n = 10), Opalescence Trèswhite Supreme 10% Hydrogen Peroxide (n = 10) and Opalescence Quick PF 45% Carbamide Peroxide (n = 10) according to the manufacturer's instructions. The control group was enamel blocks (n = 10) kept in artificial saliva. The values were obtained before exposure and after the 14-days treatment period. Enamel blocks were kept in saliva between treatments. Indent marks on enamel blocks were examined using the scanning electron microscope for treatment effects.
Results:
All four different Opalescence products damaged enamel. The most damage was done when treated for a long period (112 hours). SEM images also showed damage to enamel by all 4 products. Opalescence with 10% and with 20% Carbamide Peroxide showed the highest damage, which also differed significantly (p < 0.05) from the saliva control group (p < 0.05; Tukey-Kramer Multiple comparison test).
Conclusion:
All 4 Opalescence products damaged enamel. Higher damage was done by the 10% carbamide peroxide and 20% carbamide peroxide products because of the much longer exposure period (112 hours in comparison to 7 hours).
