The aim of this study was to evaluate clinical and radiologic outcomes of a novel device that allows simultaneous hydraulic sinus membrane elevation, bone grafting, and implant placement. A sample of 18 consecutive participants with severe atrophy of the posterior maxilla underwent transcrestal elevation of the sinus membrane and implant placement. At the 6-month follow-up, the following parameters were assessed: implant success, any complications, marginal bone loss (MBL), three-dimensional (3D) graft measurements, implant stability quotient (ISQ), and graft density. No implants failed during follow-up (10.8 ± 2.8 months; range: 7-14 months). No membrane tears or other adverse events were observed. Mean residual alveolar ridge height was 4.78 ± 0.88 mm. Six months after the procedure, the mean MBL was 0.18 mm. The mean sinus membrane elevation was 12.78 ± 2.18 mm (range: 10.7-14.23). Along the basic 3D reference planes, the dimensions of grafted bone measured around implants were as follows: axial area = 239.7 ± 57.68 mm2; sagittal area = 257.0 ± 60.83 mm2; coronal area = 143.3 ± 29.46 mm2. The mean volume of the graft was 2.38 ± 0.26 mL at baseline and 2.05 ± 0.24 mL 6 months after graft maturation (difference: 0.33 ± 0.29 mL, P = .0090). Graft density (in Hounsfield units [HU]), improved during healing from 322.0 ± 100.42 HU to 1,062.0 ± 293.7 HU; difference 740.0 ± 295.35 HU (P = .0001). The mean ISQ value was 65.5 at implant placement, and it increased to 74.1 at the 6-month examination (P = .0014). Of 18 patients, 12 experienced no pain (66.6%) and 10 experienced no swelling (55.5%). No severe pain or swelling was reported in any of the cases. The mean number of analgesic tablets consumed was 0.78 ± 0.67. Mean surgical time was 24.0 ± 4.07 minutes. The iRaise Sinus Lift System may provide a new option for minimally invasive transcrestal sinus surgery with minimal patient discomfort. A physiologic contraction of 13.9% of its original volume was experienced during healing. Long-term clinical studies are needed to confirm these preliminary results.