Analysing the effects of advanced platelet rich fibrin and concentrated growth factor on implant osseointegration with respect to the levels of TNF-alpha, RANKL, and OPG in peri-implant crevicular fluid

Introduction and Aim: Dental implants need an average of 8-12 weeks for prosthetic loading following successful osseointegration process. In order to shorten this period, various regenerative materials can be used to accelerate implant osseointegration. It is known that thrombocyte derivatives obtained by centrifugation of blood to improve bone formation. Our aim in this study is to evaluate the effects of concentrated growth factor (CGF) and Advanced-platelet-rich fibrin (A-PRF) blood materials on osseointegration of dental implants in clinical, radiological and biochemical aspects. Material and Method: Forty patients, 20 patients in the CGF group and 20 patients in the A-PRF group, who were systemically healthy and suitable for the inclusion criteria, were included in the study. Study performed with the split-mouth design, CGF or A-PRF fluid was applied to the implant surface and the implant socket in the test group. In contrast that, no additional intervention was made to the control group. Eighty dental implants were placed at 0.5 mm subcrestal level, CGF or A-PRF membrane according to the test group was applied on the operation site. The implant for the control group was placed on the contralateral site of the mouth without applying any material. Following the implant placement, plaque index, gingival index, probing depth, gingival bleeding index and TNF-α, RANKL, OPG biomarkers isolated with paper strips. Also, resonance frequency analysis was calculated intraoperatively, 4th week and 3th month. In the third month, marginal bone loss was calculated on the panoramic radiography and the mean values were analysed from the mesial and distal sections. For data analysis, Wilcoxon and Friedman tests were used together with Mann-whitney u test and Student's t test. Results: There was no significant difference between the groups in terms of plaque index, gingival index, pocket depth and gingival bleeding index (p<0.05). In the CGF-test group, the initial resonance frequency value of the implants was 74.90 ± 5.23 while it was 77.65 ± 2.81 in the A-PRF-test group. Resonance frequency value was 79.80 ± 1.76 in the third month in the CGF-test group and 78.40 ± 2.91 in the A-PRF-test group. Resonance frequency value at all times was not statistically different between the two groups (p>0.05). In the CGF-test group, the resonance frequency value at the 3rd month was found to be statistically significantly higher (p=0.001). The marginal bone loss was 0.12 ± 0.04 mm in the CGF-test group and 0.17 ± 0.06 mm in the control group. The marginal bone loss was 0.19 ± 0.08 mm in the A-PRF-test group and 0.23 ± 0.09 mm in the control group. The marginal bone loss level between the groups was not statistically significant (p=0.998). For CGF and A-PRF test groups; mean TNF-α levels at 2 weeks were 1.69 ± 1.80 and 1.69 ± 2.09 pg/mL, respectively, and at 3 months 0.64 ± 0.71 and 0.45 ± 0.38 pg/mL. The decrease in TNF-α and RANKL/OPG levels was statistically significant for both CGF and A-PRF- XV test groups (p <0.05). In the CGF-test group, the levels of RANKL at 2 weeks, 4 weeks and 3 months were 4.56 ± 4.26 pg/mL, 6.13 ± 6.89 pg/mL and 2.17 ± 2.64 pg/mL, respectively. Whereas, RANKL levels were 3.06 ± 2.38 pg/mL, 4.97 ± 4.31 pg/mL and 2.49 ± 2.30 pg/mL in the A-PRF-test group, respectively. RANKL levels were found to be statistically similar between the groups (p>0.05). The change over time wassignificant for both groups (p<0.05). It was determined that OPG levels at 2 weeks and 3 months were higher in the CGF-test group compared to the A-PRF test group (p<0.05). It was observed that RANKL/OPG ratio was higher in favor of the A-PRF-test group at the 4th week and at the 3rd month (p<0.05). Conclusion: The use of CGF in dental implantation contributes to implant osseointegration. However, CGF accelerates bone remodeling by inducing the controlled release of biochemical markers around dental implant. Keywords: Dental implant osseointegration, concentrated growth factor, advancedplatelet rich fibrin, inflammatory cytokine, peri-implant crevicular fluid