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Effect of sodium hypochlorite on primary dentin--a scanning electron microscopy (SEM) evaluation
Gisele Maria Correr1, Roberta Caroline Bruschi Alonso, Maria Fernanda Grando
1Department of Restorative Dentistry, Dental Materials Area, Piracicaba Dental School, University of Campinas, Piracicaba, São Paulo, Brazil.
Journal of Dentistry
|November 29, 2005
Summary
Sodium hypochlorite (NaOCl) significantly alters etched deciduous dentin collagen. Higher NaOCl concentrations reduce the time needed to remove the collagen fibrils network in dental applications.
Area of Science:
- Dental Materials Science
- Biomaterials
- Scanning Electron Microscopy
Background:
- Etched deciduous dentin is susceptible to chemical alterations.
- Sodium hypochlorite (NaOCl) is commonly used in dentistry but its effect on dentin collagen requires detailed evaluation.
Purpose of the Study:
- To assess the impact of varying sodium hypochlorite (NaOCl) concentrations and application times on etched deciduous dentin.
- To characterize the morphological changes in dentin collagen using scanning electron microscopy (SEM).
Main Methods:
- Deciduous anterior teeth were etched and treated with different concentrations (5% and 10%) and times (0-120s) of NaOCl.
- Scanning electron microscopy (SEM) was used to analyze the dentin surface, evaluating smear layer presence and collagen fibril alteration.
- Statistical analysis included Kruskal-Wallis and Mann-Whitney tests.
Main Results:
- All NaOCl-treated groups exhibited significant alterations in the collagen fibril network compared to controls.
- Complete collagen removal was observed with 5% NaOCl at 120s and 10% NaOCl at 30s, 60s, and 120s.
- Higher NaOCl concentrations accelerated collagen removal.
Conclusions:
- Sodium hypochlorite (NaOCl) causes significant morphological changes in etched deciduous dentin.
- The effectiveness of NaOCl in removing the collagen network is concentration-dependent, with higher concentrations requiring less time.
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