Regenerative Capacity of Leukocyte-rich and Platelet-rich Fibrin in Indirect Sinus Elevation Procedure May be Dependent on Model-Specific Modification of the Centrifugation Cycle.

CONTEXT

To compare optical density (OD) and fibrinogen content of leukocyte-rich and platelet-rich fibrin (L-PRF) generated by standard protocol (2700 rotations per minute [RPM] for 12 min) versus relative centrifugal force (RCF)-adjusted protocol across two widely used laboratory centrifuges with swing-out rotors.

AIMS

Centrifuges for PRF production generate forces in excess of 800 g. The study aimed to evaluate OD, fibrinogen content and effectiveness in bone-added osteotome sinus floor elevation (BAOSFE) of leukocyte-rich and platelet-rich fibrin (L-PRF) generated by the standard protocol (2700 RPM for 12 min) versus a RCF-adjusted protocol to generate precisely 400 g of force across two centrifuges with swing-out rotors. The outcomes were compared to a standard centrifuge configured to generate L-PRF as per the original Choukroun guidelines.

SETTINGS AND DESIGN

Sample size for the present study was calculated using proportional power calculation. A minimum sample size of 8 per group was needed to detect a bone height difference of 2 mm when the power of the test is 0.80 at a significance level of 0.05.

SUBJECTS AND METHODS

Based on the centrifuge and protocol used to generate L-PRF, 10 participants were assigned to each of the following groups are as follows: D group, fixed angle centrifuge (DUO Quattro) at default setting. R-O group: Swing-out centrifuge (Remi 8C) + standard protocol. R-A group: Remi 8C centrifuge + RCF-adjusted protocol. C-O group: Swing-out centrifuge (Remi C854) + standard protocol. and C-A group: Remi C854 + RCF-adjusted protocol. OD, fibrinogen content, and gain in bone fill and bone height after BAOSFE were the evaluated outcomes.

STATISTICAL ANALYSIS USED

Data were analyzed using GraphPad Prism Software version 6.0 (GraphPad Software Inc., La Jolla, USA) and SAS Software version 9.3 versions (SAS, New Delhi, India). Data were summarized by mean ± standard deviation for continuous data and median ± inter-quartile range for the score data. The comparison between different time points was done by analysis of one-way repeated measures test, followed by test for score data. The comparison between two groups for repeated data was made by analysis of two-way repeated measures test and followed by test. Spearman's Rho correlation test was used to test the correlation between prognosis and the other variables.

RESULTS

L-PRF from the Remi C854 centrifuge with RCF-adjusted protocol showed OD ( = 0.152) and fibrinogen content ( = 0.232) identical to those from the DUO Quattro centrifuge. L-PRF from Remi 8C centrifuge with the RCF-adjusted protocol resulted in maximum postoperative bone height gain (7.01 ± 1.44 mm) and bone fill (13.50 ± 4.51 mm) which was higher than that of the outcomes from the DUO Quattro centrifuge (6.82 ± 2.92 mm and 12.32 ± 5.31 mm).

CONCLUSIONS

A reduction in RCF resulted in a less dense clot and had a positive influence on the regenerative potential of L-PRF in BAOSFE procedure.