Efficacy of H-PRF Bone Block Versus DBBM in Transcrestal Sinus Floor Elevation: A Retrospective Cohort Study.

Objective
To compare the effect of deproteinized bovine bone matrix (DBBM) and horizontal platelet rich fibrin bone block (H-PRF-BB) in transcrestal sinus floor elevation (TSFE).Materials And Methods
This retrospective study included 65 patients receiving 73 implants placed simultaneously with TSFE. Patients were divided into two groups: (1) the H-PRF-BB group (23 patients, 24 implants) and (2) the DBBM group (42 patients, 49 implants). Cone beam computed tomography (CBCT) was obtained pre-, immediate post-surgery and at the follow-up time. Residual bone height (RBH), height of the augmented bone above the apex of the implant (AH), and height of the elevated sinus floor (EH) were measured. The differences between the groups were analyzed using Welch's t-test or Mann-Whitney U test. The correlations between RBH0 and whether the implant apex was covered with bone were evaluated through Fisher's exact probability test.Results
RBH preoperative (RBH0) and immediate postoperative (RBH1) exhibited no statistically significant difference between the two groups. The RBH at the follow up time (RBH2) in the H-PRF-BB group (11.46 ± 0.32 mm) was higher than that of the DBBM group (10.31 ± 0.30 mm), but without statistical significance. The bone height gained immediately after TSFE (EH1) was 6.39 ± 0.43 mm in the H-PRF-BB group and 5.65 ± 0.28 mm in the DBBM group (no statistical difference). Nevertheless, the bone height gained at the follow up time (EH2) was higher in the H-PRF-BB (5.39 ± 0.41 mm) group when compared to the DBBM group (4.04 ± 0.24 mm). The bone height change (ΔH) was minimal in the H-PRF-BB group (-1.02 ± 0.18 mm) compared to that in the DBBM group (-1.80 ± 0.23 mm). The mean AH immediately after surgery (AH1) was comparable in both groups, but was higher above the implant apex in the H-PRF-BB group (2.18 ± 0.28 mm) at the follow up time (AH2) when compared to the DBBM group (1.36 ± 0.16 mm). Lastly, the apex exposure rate was also lower in the H-PRF-BB group (12.5%) compared to the DBBM group (29.8%).Conclusion
H-PRF-BB showed better radiographic outcomes in TSFE compared to DBBM, with an elevated EH2 and AH2. The use of H-PRF-BB was found to reduce the height decrease over time and lessen implant exposure at the apex.