[Show abstract][Hide abstract] ABSTRACT: The current report describes the properties of a new apical barrier material formulated from carbonate-containing apatite (CAp) and collagen. CAp particles of around 50 nm were deposited on reconstituted collagen fibers. CAp/col with about 60 wt % CAp (corresponding to apatite content of bone) was obtained after 1 day of calcification. CAp content increased up to about 80 wt % in a 15-day calcification reaction. CAp/col was composed of fine calcified collagen fibers. The crystallinity and Ca/PO(4) ratio of CAp were comparable to those of bone apatite. The mixture of CAp/col and saline reached a pH of about 9. The optimum powder-to-liquid ratio (P/L) to set into a root canal was determined to be 1.2. Furthermore, the mixture (P/L = 1.2) condensed in a root canal was liquid permeable. Thus, the CAp/col was expected as an apical barrier material with osteoconductivity.
No preview · Article · Oct 2008 · Journal of endodontics
[Show abstract][Hide abstract] ABSTRACT: Aiming at creating an apical barrier material that promotes recovery of defects in the root canal, a composite of apatite and collagen was developed. To achieve this, reconstitution and cross-link of atelocollagen, and calcification of reconstituted collagen fibers, were conducted under controlled stirring at 37 degrees C. Deposits were identified as CO3-containing apatite and its crystallinity was comparable to that of bone apatite. After 20 hours of calcification, the composite contained apatite of about 60 wt%. The composite and saline mixture had a pH of about 9. The mixture was easily set into a narrow space, such as the root canal, and was liquid permeable after being set into a root canal. The biological property of the composite was examined in vivo using the molar teeth of dogs. After 8 weeks, a thin layer of new bone-like tissue was formed along the inner wall of root canal. Without the composite paste, such a new bone-like tissue was not observed. Thus, the apatite/collagen composite showed potential as an apical barrier material with osteoconductivity.
No preview · Article · Jan 2008 · Journal- Ceramic Society Japan
[Show abstract][Hide abstract] ABSTRACT: The purpose of this study was to evaluate the cleaning effect of root canal walls using strong acid electrolytic water (SAEW) as a root canal irrigant, and to investigate the influence of SAEW on the root canal dentin by micro-hardness test. Forty-three single-rooted, single-canaled teeth were instrumented using standard step-back technique with K-files. Irrigation was performed using distilled water, 5.25% NaOCl and 3% H(2)O(2), SAEW, or 15% EDTA solution in five groups. Samples were prepared to be examined under a scanning electron microscope (SEM) and micro Vickers hardness (H(V)) test machine. Our results showed that the root cleaning effects of the combined use of SAEW and NaOCl solution as root canal irrigants were equivalent to those in the group with NaOCl and 15% EDTA. When SAEW was used for 1 min under ultrasonic vibration, no decreases in the hardness of dentin inside the root canal were detected.
No preview · Article · Dec 2006 · Journal of Endodontics