EXPERIMENTAL RESEARCH USING CALCIUM PHOSPHATE PASTE ON CRANIAL SUTURE DEFECTS OF RATS

Abstract

Artificial graft substitutes are widely used in the reconstruction of bone defects. Their advantages include reduced time for surgery and no need for a donor. On the other hand, there are disadvantages such as infection risk and tissue affinity. Calcium phosphate paste (CPP) is an artificial graft substitute that becomes a self-hardening paste when powder and liquid are mixed and converts in vivo into hydroxyapatite. CPP, commercially available since 2000 has high tissue affinity, can be formed into the desired shape during surgery, and is converted gradually in vivo into biological tissue: thus, its use is increasing in the fields of orthopedic surgery and maxillofacial surgery. In this study, we created a defect in the cranial coronal suture in rats in the growing phase, and studied the histological and morphological effects of filling the defect with CPP. Histological examination indicated that the CPP was present without any gaps with the surrounding bone tissue and became incorporated into bone tissue over time with no osseous fusion in the surrounding bone tissue. The animals without CPP showed osseous fusion at the site of the suture defect. Morphological examination indicated that when compared to the animals without CPP, the animals treated with CPP showed significantly fewer effects on the growth of the cranium surrounding the site of the CPP filling. This study indicates that CPP is an extremely useful artificial graft substitute for use on the skull during the growth phase.