Armin Sokolowski

Objectives To assess in a prospective randomized trial two phycogenic bone substitutes—biphasic calcium phosphate (BCP) versus almost pure hydroxyapatite (HA)—for their volume stability and clinical implications after sinus floor elevation (SFE). Materials and Methods Twenty patients requiring lateral‐window SFE 6 months prior to implant surgery were randomized to a BCP or HA group. As primary outcome, the grafts were analyzed for volume stability, using four cone‐beam computed tomography scans obtained immediately/6/12/24 months after SFE. Secondary outcomes were implant survivval, success, periotest values, oral‐health‐related quality of life (OHIP‐G14), and pain (VAS). Results Kolmogorov–Smirnov goodness‐of‐fit test revealed normal distribution of samples ( p = .200). At 6/12/24 months, the augmented volumes decreased to 96/92/90% (HA) or 99/96/96% (BCP). Volume changes were significantly a factor of time ( p < .001; generalized linear model with repeated measures) and reached significantly lower values in HA group ( p = .018). Significant intergroup difference in volume losses was notable at 24 months ( p = .021; t ‐test for independent samples). Periotest values decreased from −3/−4.1 (HA/BCP) after implant placement to −6.3/−4.5 (HA/BCP) after 6 months. OHIP scores diverged at 2 months (HA: 9.5; BCP: 5.2) and largely resolved by 24 months (HA: 1.3; BCP: 1.9). VAS scores were comparable, 2.2 at 1 week after SFE being their highest mean level. Conclusions After 2 years, both groups experienced no biological or technical complications, demonstrating a consistent healing trajectory without notable symptoms. Although no significant differences were observed in implant stability and survival, BCP demonstrated higher volume stability than HA.