To achieve our purposes, an experimental ex vivo study was carried. This research project was approved by the University of Damascus Local Research Ethics Committee (UDDS-3045PG.) and was funded by the Damascus University Postgraduate Research Budget (97687027834DEN). The sinus floor elevations were done on 18 bisected heads of lambs aged between 6 and 12 months that were slaughtered in a maximum of 4 h before the procedures began. CBCT images of the heads were taken using the Picasso® Pro CBCT system (Vatech™, Seoul, South Korea) set at a voxel size of 0.2 mm, tube current of 5 mA, tube voltage of 83 KV with gray scale of 16 bit per pixel. A standardized position of the lamb’s heads was maintained by the correct head orientation in accordance with the 3D intersecting planes of the red beam. Then, the images were analyzed for the best location to perform the sinus elevation where remaining bone height (RBH) is less than 5 mm on 3DOnDemand® programme (CyberMed, Finland) (Fig. 1). The RBH was measured from the apical tip of the buccal root on the third premolar which will be extracted to the floor of the sinus. The sample was randomized by generating random numbers using Research Randomizer software (http://www.randomizer.org/) [11] making sure that the same method was not done on the same lamb twice.

After the extraction of the third premolar, the mesial side of the sinus was exposed (Fig. 2) in order to check the sinus for any perforations. The elevation height was measured using a depth gauge, and the intended elevation height was 7 mm. If this height was not achieved, the maximum elevation was recorded. When a perforation of the membrane was present, its length was measured using a periodontal probe.

Bone blocks were harvested from the lamb’s head and made into soft bone particles using ACE bone mill®(ACE surgical Supply Co., Inc., Brockton, Ma, USA). For this technique, the osteotomy started with a pilot drill for 2 mm followed by burs with increasing diameter up to 3.2 mm. Then, osteotomes (FRIALIT-2 bone expander, Friadent, DENTSPLY Implants) were used to expand the osteotomy and to break the sinus floor after the addition of bone. The 4.5 mm osteotome was used to break the sinus floor and push continuous insertions of bone particles. Every use of the osteotome to pack the bone is expected to lift the sinus membrane for 1 mm [12].