Using a reamer instead of the osteotomes for breaking the sinus floor has the advantage of creating a thin bone shell that prevents direct contact between the drill and the Schneiderian membrane [24]. Moreover, using a reamer has been shown to cause less discomfort and nausea when compared to the osteotome technique as a result of the constant tapping of the osteotomes [25]. As a result, the CAS kit has the advantage over the BAOSFE and the balloon in preparing the osteotomy and breaking the sinus floor safely and with less complications. Moreover, it was noted during our study that using a drill gives better feedback to the surgeon when breaking the sinus floor compared to the osteotome.

However, in our study, the CAS-kit was able to lift the membrane for a maximum of 5 mm. We believe that the saline pressure injected through the hydraulic lifter from a syringe is small and decreases gradually after leaving the lifter, whereas a study on the Jeder system showed a height gain of (9.2 ± 1.7 mm). This could be attributed to the high hydraulic pressure from the Jeder pump which is a machine that control the hydraulic pressure [23]. On the other hand, in our study, the balloon was able to lift the membrane for 7 mm in all cases; therefore, the balloon was better in elevating the mucosa.

Our study compared between three techniques for SFE for elevation heights of 7 mm. The 7 mm elevation height was chosen as a previous study by Stelzle et al. 2011 showed that BAOSFE caused perforations in the mucosa in all samples for perforation heights of 10 mm [7]. Therefore, we tried to set a threshold that might be achieved with internal sinus lifting techniques and be feasible in clinical practice. Perforations were checked using the three different methods: the mesial window, using a depth gauge, and the injection of saline solution through the osteotomy, which allowed for accurate recording of perforations.