RESUMO
BACKGROUND: The degradation speed of biological materials is critical for the clinical use of guided bone regeneration.The partial biological characteristics and treatment efficacy of concentrate growth factor (CGF) fibrin have been explored preliminarily, but its degradation properties have not yet been reported.OBJECTIVE: To explore the degradation properties of CGF fibrin and platelet-rich fibrin (PRF) in artificial saliva and compare the degradation speed of these two biological products.METHODS: Ten volunteers were selected, and 18 mL of venous blood from each volunteer was extracted and stored in two vacuum blood collectors. The blood samples were then placed into the drum of the Medifuge centrifugal acceleration machine, to separate CGF fibrin and PRF specimens following the preparation process, respectively. Both CGF fibrin and PRF specimens were respectively made into bulk and membranoid, and were then immersed in artificial saliva under 37 ℃. The mass of the bulk specimens and area of the membranoid specimens were measured regularly, and the degradation processes of CGF and PRF were recorded. The degradation curves were drawn to compare the degradation speed of CGF fibrin and PRF.RESULTS AND CONCLUSION: The mass of CGF fibrin and PRF showed no significant difference at the 5th day (P >0.05), while the mass of CGF fibrin was higher than that of PRF at the 3rd, 4th and 6th days (P < 0.05). The residual area of CRF was significantly larger than that of PRF at posttreatment 1-6 days (P < 0.05). To conclude, the degradation speed of bulk or membranoid CRF is slow than that of PRF in artificial saliva. The higher the fibrin content is, the slower the degradation ability is, indicating the strong bioreproductive function.
RESUMO
<p><b>OBJECTIVE</b>To investigate the changes in the expression of phospholipase C-gamma1tyr783 (PLC-γ1tyr783) in the condylar cartilage of a young rat during functional mandibular protraction. This work also explores the function of PLC-γ1tyr783 in the rat mandibular condylar cartilage bone remodeling, which could provide experimental evidence for clinical bone ortho- pedic work.</p><p><b>METHODS</b>A total of 60 four-week-old male Sprague-Dawley (SD) rats were used in this study. The rats were divided equally and randomly into experimental group and control group. The functional appliances that were fitted to the upper incisors of the animals in the experimental group were worn 24 h a day after the rats were fed for 7 d with homemade pellet feed. The animals in the experimental group, along with their matched controls, were sacrificed after 1, 3, 7, 14, 21, and 28 d. The bilateral condylar was fixed, decalcified, dehyded, and then conventional paraffin embedded. Immunohisto- chemistry of PLC-γ1tyr783 was applied to observe its express distribution and variation.</p><p><b>RESULTS</b>The expression of PLC-γ1tyr783 decreased gradually in the control group, which showed age-related changes (P > 0.05). On the 14th day, PLC-γ1tyr783 expres- sion in the experimental group was significantly higher than that in the control group. PLC-γ1tyr783 expression began to appear statistically and significantly different between the two groups (P < 0.01).</p><p><b>CONCLUSION</b>PLC-γ1tyr783 is involved in the bone remodeling process of the rat condylar cartilage after functional mandibular-protraction.</p>