Hartlev J, et al. - Using autogenous bone graft covered by either a platelet-rich fibrin membrane in the test group or an inorganic bovine bone substitute and a resorbable collagen barrier membrane in the control group, authors examined the volumetric changes after lateral alveolar ridge augmentation among 27 partially edentulous cases. They noted the mean bone volumetric loss in the test group, 14.7%, and 17.8%, in the control group. They observed a larger amount of bone resorption in the incisor and canine region as compared to in the premolar region of the maxilla, particularly in the control group.