An evaluation of the effect on lower extremity fracture healing of collagen-based fusion material containing 2 different calcium phosphate salts: An experimental rat model

Abstract

Background. Collagen-based synthetic bone grafts which contain tricalcium phosphate (TCP) and hydroxyapatite (HA), and collagen-based synthetic bone grafts containing only TCP have some advantages compared to autografts. Therefore, these grafts are frequently used to fill bone defects and pseudoarthrosis. Objectives. The aim of this study was to evaluate and compare the clinical, radiological and histopathological effects of TCP-HA and TCP alone + Type-1 collagen in healing lower extremity fractures in a pseudoarthrosis model in rat femurs. Material and methods. A total of 36 female Wistar rats were randomly separated into 4 groups. Group 1 (n = 10) was the control group. A femur pseudoarthrosis model was created in Groups 2, 3 and 4. On the 90 th day after the 1 st surgery in Group 2 (n = 10), TCP-HA + Type-1 collagen was applied, in Group 3 (n = 10), TCP alone + type-1 collagen was applied, and in Group 4 (n = 6, the placebo group), saline solution was applied. Fixation was performed with an intramedullar pin. After 60 days and clinical and radiological scoring, all animals were sacrificed and a histopathological evaluation of the pseudoarthrosis areas was conducted. Results. In all the clinical, radiological and histopathological measurements used in the evaluations of the differences between the groups, a higher rate of union was determined in Group 2 (TCP-HA). No significant difference was determined between Group 3 and Group 4 in terms of union rates. Conclusions. The clinical, radiological and histopathological results of this study showed that TCP alone was less effective than TCP-HA in the union of a femur pseudoarthrosis model in rats. The reason for this difference was considered to be hydroxyapatite (HA).

A Biological Study of Composites Based on the Blends of Nanohydroxyapatite, Silk Fibroin and Chitosan

“…et al indicated, it is extremely difficult to connect nanoparticles with natural polymers to obtain a homogenous composite [ 6 ]. Nevertheless, according to Aksekili A.M.E. et al [ 7 ], scaffolds with different types of composition with hydroxyapatite (HA) appear promising for the treatment of pseudoarthrosis, due to their biocompatibility and long biodegradation time. Furthermore, in the review by Miriam Filippi et al [ 8 ], we find many examples of different materials based on natural polymers and hydroxyapatite, such as hyaluronic acid, keratin, fibrin, gelatin, silk fibroin (SF), collagen, heparin, chitosan (CTS), alginate, starch, agar, dextran, cellulose, carrageenans or gellan gum.…”