ایمان حفار

Facilitating the fracture healing process is important to increase the fracture healing speed and to decrease the time period till union. This study aimed to evaluate the effects of blood clot and doxycycline on bone healing process.

Twenty mature male New Zealand white rabbits were used, in this study. A defect was created in the middle part of the radius. The rabbits were randomly distributed into 4 groups and the gaps were filled with the graft materials: blood clot, doxycycline, combination of blood clot and doxycycline and control group in which the defect was left empty. Radiographs of operated limbs were taken on 14th, 28th, 42nd and 56th postoperative days. Histologic samples were taken on the 56th day post surgery.

On radiographic evaluation significant difference between the groups was not observed (p>0.05). On histopathological evaluation, blood clot and doxycycline groups were superior to control group (P<0.05), also combination of blood clot and doxycycline group was superior to other ones (P<0.05). There was no evidence of graft rejection in any group.

This study demonstrated that the combination of blood clot and doxycycline has a better function in bone healing process than other groups.

Phenytoin ointment is a usual medicine for wound healing. Aloe vera gel promotes wound healing by directly stimulating the activity of macrophages and fibroblasts that increase both collagen and proteoglycan synthesis, thereby promoting tissue repair. The aim of this study was to evaluate the effects of phenytoin ointment1%, aloe vera gel, royal jelly and honey on skin wound healing in rabbit animal model.

5 rabbits with 50 skin wounds were used in this study. Phenytoin ointment1%, aloe vera gel, royal jelly and honey were used in four wounds and another was considered as an untreated control. Macroscopic study was performed on days 4, 8, 12, 16 and 20 after wounding and histopathologic study was done on the days 10 and 21 from the wounds.

On the 8th and 12th days in the Aloe vera gel, royal jelly and honey groups, the area of the wound had a significant difference (p < 0.05) than group1 (phenytoin), indicating a faster reduction of the wound surface than the phenytoin group. On the 16th day after surgery, the ulcer surface of the honey group was completely closed and on day 20 all the wounds were fully restored in all groups. Also, histopathologic studies on 10 and 21 days showed no significant difference between the studied groups and all wounds were completely restored on day 20.

Finally, the results of this Study showed that phenytoin 1% ointment, aloe vera gel, royal jelly and honey, all had a good effect on wound healing.

Acceleration of bone healing is one of the most challenging issues in orthopedic science. This study aimed to evaluate bone healing process with the application of fish bone powder and human lyophilized platelet (prepared with a novel protocol) in the rabbit animal model.

  This study was carried out on 20 male New Zealand white rabbits (12 month old), divided into four equal groups as control, fish bone powder, lyophilized platelet and a combination of fish bone powder and lyophilized platelet. After exposing the radius, a bone segment (10 mm) was cut from the bone, and the empty space was left empty in the control group but filled with the mentioned biomaterials in other groups. Radiographs of each rabbit were taken on the 14th, 28th, 42nd, and 56th post-operative days to evaluate bone formation, union and remodeling of the bone defect. All animals were euthanized on the 56th post-operative day for histopathological evaluation.

Radiological evaluation showed a significant difference between the lyophilized platelet group (P=0.02) and the control (P=0.007) and the fish bone powder (P=0.005) on 56th post-operative day, where the lyophilized platelet group was superior, compared to other groups. Moreover, the histopathological evaluation revealed a significant difference between the control group (P=0.01), the fish bone powder (P=0.03) and lyophilized platelet group (P=0.01), where treatment groups were superior, compared to the control group on 56th post-operative day. Nonetheless, there was no evidence of graft rejection in all groups.

According to the results of the study, using lyophilized platelet could accelerate the bone healing process in rabbit and has the potential for use in medicine.