Objective Slit‐window technique is a lateral approach sinus floor elevation (SFE) procedure that utilizes a rigid resorbable membrane in conjunction with stabilizing bony slits to tent the Schneiderian membrane without addition of grafting materials. The aim of this randomized clinical trial was to compare clinical and radiographic outcomes of the Slit‐window SFE with those of SFE with bone grafting. Material and Methods Thirty‐three patients with 38 edentulous sites were included. Edentulous sites were randomly allocated to the Slit‐window SFE or SFE with bone grafting. Simultaneous with SFE, each site received two dental implants. Implant stability quotient (ISQ) values were recorded at baseline and monthly visits for 8 months. The bone coverage and bone height gain at implant sites were recorded on cone beam computed tomography (CBCT) scans 6 and 24 months postoperatively. Results There were no significant differences in the mean ISQ values between the groups at any time point (p > 0.05). All implants in both groups were found to have complete bone coverage. Significant increases in the bone height were found 6 and 24 months postoperatively in both groups (p < 0.001). Conclusions Within limitations of the present study, it can be concluded that the Slit‐window SFE technique without the need for bone grafting resulted in sufficient bone height gain around implants placed simultaneous with the SFE procedures. The bone height around these implants was stable during the 2‐year follow‐up period. The treatment outcomes for these implants were comparable to those placed simultaneous with lateral approach SFE in conjunction with bone grafting.

Introduction Implant placement in an atrophic posterior maxilla is challenging due to sinus pneumatization and presence of insufficient bone volume. Sinus floor elevation (SFE) is a feasible approach to increase the available alveolar bone dimensions. It is known that the maxillary sinus has a potential for healing and bone formation without the need of bone grafts or bone substitutes. However, current graft‐free sinus SFE approaches are technique sensitive and non‐reliable in consistent bone formation. This paper introduces the slit‐window technique as a novel and simple technique to perform graft‐free sinus floor elevation. Case Presentation A 66‐year‐old male presented with edentulous regions in the posterior maxilla and bilateral sinus pneumatization. The treatment included SFE using the graft‐free slit‐window technique on the right site and traditional lateral SFE with bone augmentation on the left site. Two implants were placed simultaneously during sinus lift procedures in each side. The slit‐window technique was performed using a rigid barrier membrane in conjunction with stabilizing bony slits to tent the Schneiderian membrane superiorly. Healing was uneventful for implants in both sides. Six months postoperatively, the amount of bone formation in the non‐grafted site was comparable to that of the grafted site. Conclusion Slit‐window sinus floor elevation procedure is a simple technique to elevate the floor of the sinus without the need for bone grafting.