Changes in micro-TBS to pulp chamber dentin after the application of NaOCl & reversal effect by using sodium ascorbate.
10.5395/JKACD.2009.34.6.515
- Author:
Su Mi KWON
1
;
Tae Gun KIM
;
Mi Kyung YU
;
Kwang Won LEE
Author Information
1. Department of Conservative Dentistry, School of Dentistry & Institute of Oral Bioscience, Chonbuk National University, Korea. lkw@chonbuk.ac.kr
- Publication Type:Original Article
- Keywords:
micro-TBS to Pulp Chamber Dentin;
NaOCl;
Reversal Effect;
Sodium Ascorbate
- MeSH:
Ascorbic Acid;
Dental Pulp Cavity;
Dentin;
Sodium
- From:Journal of Korean Academy of Conservative Dentistry
2009;34(6):515-525
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
Clinical suggestion for the limitation of application time of NaOCl solution is needed to avoid large reductions in resin-dentin bond strength. The aim of this study was to measure the change of micro-tensile bond strength after the various application time of 5.25% NaOCl solution to pulp chamber dentin in endodontic access cavity, and to evaluate the effect of 10% sodium ascorbate application for 10 min on bond strength after the treatment of 5.25% NaOCl solution. In this experiment, there were no statistical differences(p>0.05) in bond strengths between upper chamber dentin and lower chamber dentin. NaOCl-treated group for 20 min did not show any significant decrease(p>0.05) in bond strength than non-treated control group. In contrast to that, bond strengths of NaOCl-treated groups for 40 & 80 min were significantly lower(p<0.05) than that of non-treated control group. 10% sodium ascorbate retreated group for 10 min after 5.25% NaOCl application for 40 min to chamber dentin showed the recovery of bond strength significantly. However, the bond strength of sodium ascorbate retreated group after 5.25% NaOCl application for 80 min was still significantly lower(p<0.05) compared to the non-treated control group, which means the reductions in resin-dentin bond strength were not fully reversed. On the contrary, sodium ascorbate retreated group after 5.25% NaOCl application for 5 min showed significantly higher(p<0.05) bond strength compared to the control group, which demonstrates its superior recovery effect. In SEM exminations of specimens retreated with 10% sodium ascorbate after NaOCl application for 40 & 80 min showed that resin tags were formed clearly and densely, but weakly in density and homogeneity of individual resin tag compared to the control specimen.
