Introduction: Comparing the epidemiology of fractures originating in the cervical and apical regions may help to understand the causes and risk of a vertical root fracture. We aimed to determine the frequency of vertical root fractures in different fracture sites and how the fracture site relates to fracture direction and post length.
Methods: Teeth diagnosed with a vertical root fracture were retrospectively surveyed for age and sex of the patient, type of tooth, a fracture region in the longitudinal axial direction, site of the fracture, and presence of a post.
Background: Bone perforation may induce bone marrow cell migration into a collagen sponge onlay implant. This study investigated the efficacy of bone perforation and collagen sponge onlay placement with regard to new bone formation.
Methods: One hundred sixty femurs of 80 Wistar male rats were used in four groups: bone perforation and sponge (PS) group: after perforating the femur, fibrillar and heat-denatured collagen (FC-HAC) sponges were placed on the femur; sponge (S) group: a FC-HAC sponge was placed directly on the femur without bone perforation; perforation (P) group: femur perforation without collagen sponge placement; and control (C) group: neither bone perforation nor sponge placement was used.