RESUMEN
PURPOSE: The objective was to investigate changes in bone height after implant placement in combination with simultaneous internal sinus lift (ISL) without graft material. MATERIALS AND METHODS: For a retrospective clinical study, 101 implants placed in combination with ISL without graft were selected. The study included 66 patients (mean age 59.6 years) with radiographs from baseline (T0) and two follow-ups after mean times of 7 months (T1) and 17 months (T2). Apical changes in bone height were measured at the mesial and distal aspects of the implant. Correlation analysis was performed to identify factors affecting changes in bone height. RESULTS: Mean apical bone gains of 1.0 mm (mesial) and 1.7 mm (distal) were observed at T1. At T2, mean apical bone gains were 1.5 mm and 2.1 mm (distal). The change in apical bone height was significant between T0 and T1, between T0 and T2, and between T1 and T2. Rank correlation analysis revealed a significant correlation (Spearman rho: -0.2 to -0.4) between small initial bone height and a greater amount of apical bone gain. CONCLUSIONS: A gain in apical bone height can be expected if implants are placed in combination with ISL without graft material. Variability is high, however.