The effect of subcutaneous Insulin-like Growth Factor-1 (IGF-1) injection on rabbit auricular cartilage autograft viability.

Insulin-like Growth Factor-1 (IGF-1) is one of the significant substances affecting the growth and development of cartilage tissue in the body. The aim of this study is to evaluate the possible histopathological effects of local IGF-1 injection on the viability of rabbit auricular cartilage autografts. To this end, the single-piece and sliced cartilage tissues obtained from 20 albino rabbits' auricula were implanted in the subcutaneous pockets created on the back skins of the experimental animals. Every two weeks IGF-1 (10 mg/ml) injections were performed on the autograft implants of one group and normal saline (0.9%) injections were performed on the other group. Experimental animals were sacrificed at the end of the third month. A total of 34 tissue samples obtained after dissection were evaluated and scored histopathologically according to their cartilage viability, environmental reaction, and regenerative activities. The intergroup evaluation carried out for the single-piece and sliced cartilage grafts revealed that there was statistically more cartilage viability and less foreign-body reaction in the IGF-1 group than the normal saline group (p<0.05). While there was a statistically significant difference between the groups for single-piece grafts regarding regenerative activity (p<0.05), there was no significant difference for sliced grafts. The IGF-1 group, however, showed more activity. The results we obtained point out to the fact that IGF-1 increases the tissue viability of the implanted auricular autograft and it suppresses immune modulation effect.

The comparison of thermal tissue injuries caused by ultrasonic scalpel and electrocautery use in rabbit tongue tissue.

The aim of this study compares to the increase in tissue temperature and the thermal histological effects of ultrasonic scalpel, bipolar and unipolar electrosurgery incisions in the tongue tissue of rabbits. This study evaluates the histopathological changes related to thermal change and the maximum temperature values in the peripheral tissue brought about by the incisions carried out by the three methods in a comparative way. To assess thermal tissue damage induced by the three instruments, maximum tissue temperatures were measured during the surgical procedure and tongue tissue samples were examined histopathologically following the surgery. The mean maximum temperature values of the groups were 93.93±2.76 Cº for the unipolar electrocautery group, whereas 85.07±5.95 Cº for the bipolar electrocautery group, and 108.23±7.64 Cº for the ultrasonic scalpel group. There was a statistically significant relationship between the increase in maximum temperature values and the separation among tissue layers, edema, congestion, necrosis, hemorrhage, destruction in blood vessel walls and fibrin accumulation, and between the existence of fibrin thrombus and tissue damage depth (p<0.05). It was concluded that the bipolar electrocautery use gives way to less temperature increase in the tissues and less thermal tissue damage in comparison to the other methods.