In vivo estimation of periapical bone reconstruction by chondroitin sulfate in calcium phosphate cement

Biphasic calcium phosphate cements using an equimolar mixture of tetracalcium phosphate and dicalcium phosphate dihydrate (TeDCPD) for the powder phase were experimentally developed for endodontic clinical use. The liquid for standard cement (CP-1) in this study was 2.1% citric acid solution. In the liquid for the modified cements, 2% (CP-2) or 6% (CP-3) chondroitin sulfate (CS) was added. The microstructure of the cements was observed by scanning electron microscope (SEM). X-ray diffraction analyses (XRD) were also performed. The cements were respectively placed in prepared mandibular first molar canals of rats. Results of SEM and XRD examinations of the cements indicated that the addition of CS accelerated the setting reaction of calcium phosphate cement. In experimental periapical lesion, alveolar bone could be significantly reconstructed with polarized cells along the margin using CP-3, but CP-1. It seems that CS in TeDCPD compound induce osteoblasts or osteoblast-like cells.