Comparison of effect on repair of bone defect using pedicle fascial flap promoting tissue engineering complex guided by membrane and vascularization / 中国综合临床

ABSTRACT

Objective The tissue engineering technique and the microsurgery technology is combined to construct the uncellular tissue engineering complex with vascularization and membrane guided dual effect. Through comparing study of using the simple biomembrane guided bone regeneration technique to construct the uncellular tissue engineering complex to repair the large segment bone defect in the animal body,the bone reparative effect of the tissue engineering bone wrapped by pedical fascial flap with vessels and that wrapped by the simple biomembrane was compared, thus to provide experimental evidence for the clinical application. Methods Twenty-four Newzland 5-month-old rabbits were used to build the bilateral periosteumincluded bone defect modelsin the middle piece of the ulna and the length of the defect was 1 cm. Autologous red bone marrow was implanted in the tissue engineering bone which was prepared by osteoinductive absorbing material including BMP. The prepared tissue engineering bone was implanted in the bone defect area. The right side was wrapped by the simple absorbable biomembrane, whereas the left side was wrapped by pedical fascial flap with blood supply. At the fourth, eighth, twelfth and sixteenth week after the operation each group was examined by the radiograph (x-ray), the light density measurement, gross morphology and histological inspection,bone shape measurement analysis in the repairing area and the biomechanics measurement at the twelfth week. The data was analyzed to test the difference of the bond defect repair. Results The radiograph, gross morphology and histological inspection showed the growth of vessels in the implant area, the quantity and the forming speed of the bone trabecula and, the cartilaginous tissue, the formation of the mature bone structure,remodeling of the diaphysis, recanalization of the cavum ossis and the absorption and the degradation of the implant of the group of pedical fascial flap with blood supply was superior to that of the group of the simple absorbable biomembrane. At the fourth, eighth, twelfth and sixteenth week after the operation the bone trabecula area were( 20. 35 ± 2. 41 ) %, ( 40. 21 ± 1.97 ) %, (66. 67 ± 3.44 ) % and ( 86. 47 ± 3.99) % respectively in the group of pedical fascial flap with blood supply, and were ( 7. 46 ± 2.64 ) %, ( 20. 66 ± 2. 28 ) % , ( 40. 22 ±1.84)% and(58. 18 ± 1.79) respectively in the group of the simple absorbable biomembrane. At the same time point after the operation the light density were 0. 636 ± 0. 012,0. 596 ± 0. 062,0. 552 ± 0. 009 and 0. 451 ±0. 008 respectively in the group of pedical fascial flap with blood supply, and 0. 742 ± 0. 032,0. 713 ± 0. 022,0. 655 ±0. 018 and 0. 606 ±0. 015 respectively in the group of the simple absorbable biomembrane. The units of blood vessel reproductive area in the bone repair junctional zone were ( 18.75 ± 2. 09 ) %, ( 37.41 ± 3.22 ) %,(53. 06 ±2. 18)% and (36.72 ±4. 73)% respectively in the group of pedical fascial flap with blood supply,and (5. 34 ± 1.17 ) %, (9. 48 ± 2.96) %, ( 22.43 ± 2. 21 ) % and ( 26. 27 ± 3. 14 ) % respectively in the group of the simple absorbable biomembrane. The biomechanics intension was 26.62 ± 3.96 in the group of pedical fascial flap with blood supply and 18. 38 ±0. 71 in the group of the simple absorbable biomembrane at the twelfth week after the operation. All of the differences were significant( P ＜0. 05 ). Conclusion The pedical fascial flap with blood supply has significant effect in promoting the tissue engineering bone to vascularize and promoting the bone formation by vascularization. The membrane guided bone regeneration technique restricted not only the growth of the fibrous connective tissue in the reparative process of the large segment bone defect effectively, but also the ability of fast and effective vascularization, thus the chronic creep and substitution process would be needed. Simple application of the biomembrane can compensate the shortcoming of chronic creep of the implanted material by the growth of the external callus.