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Ratiometric Imaging of Extracellular pH in Dental Biofilms
Published on: March 9, 2016
Influence of calcium hydroxide on dyes for dentin labeling, anlyzed by means of a new methodology
Ivaldo Gomes de Moraes1, Fernanda Gomes de Moraes, Graziela Garrido Mori
1Bauru Dental School, University of São Paulo.
Abstract:
The objective of this study was to evaluate the influence of calcium hydroxide in intracanal dressing on the ability of the dyes rhodamine B and methylene blue to label the dentine. Forty extracted human mandibular premolars had their canals instrumented and were divided into four groups: in two groups, the canals were filled with a calcium hydroxide paste and the others remained in distilled water. After 15 days, in two groups (with and without dressing), the canals were obturated with sealer containing methylene blue, whereas the others contained rhodamine B. For analysis, the roots were transversally sectioned in their cervical, medium and apical thirds, and the labeling was analyzed. The Mann-Whitney test showed statistically significant difference between the dressing/methylene blue group and the others. Based on these results, it was concluded that calcium hydroxide in intracanal dressing negatively interferes with the labeling ability of methylene blue.
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