Effects of blood and root-dentin cleaning on the porosity and bond strength of a collagen bioceramic material.

To assess the effect of cleaning protocols on dentin contaminated with blood in reparative endodontic materials, bovine root samples were divided: no contamination (N); contamination (P); contamination and cleaning with saline (S), 2.5% NaOCl+saline (Na) or 2.5% NaOCl+17% EDTA+saline (NaE) and filled with: mineral trioxide aggregate (MTA), calcium-aluminate-cement (C), or C+collagen (Ccol) (n=13). The samples were evaluated for porosity, chemical composition, and bond strength. MTA porosity was lower than C (p=0.02) and higher than Ccol (p<0.001). P and NaE were similar (p=1.00), but higher than the other groups (p<0.001). MTA bond strength was similar to Ccol (p=0.777) and lower than C (p=0.028). P presented lower bond strength than the N (p<0.001); S and Na were similar to each other (p=0.969), but higher than P and lower than N (p<0.001). It was observed a predominance of mixed and cohesive failures. None of the samples showed Ca/P ratio values similar to human hydroxyapatite. This study showed that contamination with blood increased the materials porosity, but dentin cleaning with 2.5% NaOCl reduced this effect, and the collagen additive reduced the material porosity. Furthermore, blood contamination reduced the materials bond strength, and cleaning with saline or 2.5% NaOCl diminished this effect.

Effects of blood and root-dentin cleaning on the porosity and bond strength of a collagen bioceramic material

Abstract To assess the effect of cleaning protocols on dentin contaminated with blood in reparative endodontic materials, bovine root samples were divided: no contamination (N); contamination (P); contamination and cleaning with saline (S), 2.5% NaOCl+saline (Na) or 2.5% NaOCl+17% EDTA+saline (NaE) and filled with: mineral trioxide aggregate (MTA), calcium-aluminate-cement (C), or C+collagen (Ccol) (n=13). The samples were evaluated for porosity, chemical composition, and bond strength. MTA porosity was lower than C (p=0.02) and higher than Ccol (p<0.001). P and NaE were similar (p=1.00), but higher than the other groups (p<0.001). MTA bond strength was similar to Ccol (p=0.777) and lower than C (p=0.028). P presented lower bond strength than the N (p<0.001); S and Na were similar to each other (p=0.969), but higher than P and lower than N (p<0.001). It was observed a predominance of mixed and cohesive failures. None of the samples showed Ca/P ratio values similar to human hydroxyapatite. This study showed that contamination with blood increased the materials porosity, but dentin cleaning with 2.5% NaOCl reduced this effect, and the collagen additive reduced the material porosity. Furthermore, blood contamination reduced the materials bond strength, and cleaning with saline or 2.5% NaOCl diminished this effect.

Resumo As amostras de raízes bovinas foram divididas em: sem contaminação (N); contaminação sanguínea (P); contaminação sanguínea e limpeza com soro fisiológico (S), 2,5% NaOCl+soro fisiológico (Na) ou 2,5% NaOCl+17%EDTA+soro fisiológico (NaE) e preenchido com: agregado de trióxido mineral (MTA), cimento de aluminato de cálcio (C), ou C+colágeno (Ccol) (n=13). A porosidade do MTA foi menor que C (p=0,02) e maior que Ccol (p<0,001). P e NaE foram semelhantes (p=1,00), mas superiores aos demais grupos (p<0,001). A resistência de união do MTA foi semelhante ao Ccol (p=0,777) e inferior ao C (p=0,028). P apresentou menor resistência de união que o N (p<0,001); S e Na foram semelhantes entre si (p=0,969), porém maiores que P e menores que N (p<0,001). Este estudo mostrou que a contaminação com sangue aumentou a porosidade dos cimentos, mas a limpeza da dentina com NaOCl 2,5% reduziu esse efeito, e o aditivo de colágeno reduziu a porosidade dos cimentos. Além disso, a contaminação sanguínea reduziu a resistência de união dos cimentos e a limpeza com solução salina ou NaOCl 2,5% diminuiu esse efeito.