Cha JK, et al. - In this study, authors examined 40 cases to quantify the influence of alveolar ridge preservation on vertical changes in the posterior maxilla vs spontaneous healing after tooth extraction. They observed a stable level of the sinus floor over time (baseline to 6 months) in the test group [-0.14mm (-0.31, -0.02)]. As compared to the test group, the sinus floor level shifted more coronally [-1.16mm (-1.73, -0.61)] in the control group. In the test group, a significantly larger residual bone height was reported vs the control group at 6 months [7.30mm (6.36, 8.20) vs 4.83mm (3.94, 5.76), respectively].