A comparison of the clinical and histologic efficacy of ridge preservation with freeze-dried bone allograft and a collagen membrane as compared to extraction only for implant site development

Background. Tooth extraction often leads to loss of ridge width and height. The aim of this randomized, controlled, blinded, clinical study was to determine if ridge preservation would prevent post-extraction resorptive changes as assessed by clinical and histologic parameters.; Methods. 24 patients requiring an extraction and delayed implant placement were randomly selected to receive either extraction alone (EXT) or ridge preservation (RP) using freeze-dried bone allograft (FDBA) and a collagen membrane. Following atraumatic extraction, horizontal and vertical ridge dimensions were determined using a digital caliper and a stent. Groups were subdivided to receive implant placement at either 4 or 6 months. Prior to implant placement 2.7 x 6 mm trephine cores were obtained and preserved in formalin for histologic analysis.; Conclusions. Ridge preservation using FDBA and a collagen membrane improved ridge height and width dimensions when compared to extraction alone. These dimensions may be more suitable for implant placement especially in areas where loss of ridge height would compromise the esthetic result. The quantity of bone observed on histologic analysis was greater in preservation sites although these sites included both vital and nonvital bone. (Abstract shortened by UMI.)...