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Effect of bleaching on the cemento-enamel junction
Roberta Esberard1, Renata R Esberard, Roberto M Esberard
1Department of Pathology, Bauru Dental School, University of São Paulo, Brazil. roesberard@hotmail.com
American Journal of Dentistry
|October 3, 2007
Summary
Dental bleaching agents can alter the cemento-enamel junction (CEJ), leading to increased dentin exposure. This study used scanning electron microscopy (SEM) to analyze these morphological changes in human teeth.
Area of Science:
- Dentistry
- Dental Materials Science
- Microscopy
Background:
- Dental bleaching is a common cosmetic procedure.
- The cemento-enamel junction (CEJ) is a critical area of the tooth.
- Understanding the effects of bleaching on the CEJ is important for clinical practice.
Purpose of the Study:
- To evaluate the impact of various dental bleaching agents on the human tooth's cemento-enamel junction (CEJ).
- To assess morphological alterations at the CEJ using scanning electron microscopy (SEM).
Main Methods:
- Thirty intact human teeth were sectioned into 60 specimens.
- Specimens were divided into six groups and subjected to different bleaching protocols (carbamide peroxide, hydrogen peroxide, sodium perborate).
- Scanning electron microscopy (SEM) was used to examine morphological changes at the CEJ after bleaching.
Main Results:
- All tested bleaching agents induced morphological changes at the cemento-enamel junction (CEJ).
- Increased dentin exposure was observed at the CEJ following bleaching treatments.
- SEM analysis revealed distinct alterations in the CEJ structure.
Conclusions:
- Dental bleaching agents can adversely affect the cemento-enamel junction (CEJ).
- Increased dentin exposure at the CEJ is a potential consequence of dental bleaching.
- Further research is needed to mitigate these effects and ensure tooth integrity.
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