Open healing of contained and non-contained extraction sockets covered with a ribose cross-linked collagen membrane: a pilot study

PURPOSE: This study investigated whether the placement of ribose cross-linked collagen (RCLC) membranes without primary soft tissue closure predictably resulted in sufficient alveolar ridge preservation in contained and non-contained extraction sockets. METHODS: Membranes were positioned across extraction sockets, undermining full-thickness flaps, and the gingival margins were fixed by double-interrupted sutures without crossed horizontal mattress sutures for 1 week. In non-contained sockets, a bone substitute was used to support the membrane within the bony envelope. Radiographs and clinical images obtained 4 months later were analyzed by ImageJ software using non-parametric tests. RESULTS: In 18 patients, 20 extraction sockets healed uneventfully and all sites received standard-diameter implants (4.1, 4.8, or 5.0 mm) without additional bone augmentation. Soft tissues and the muco-gingival border were well maintained. A retrospective analysis of X-rays and clinical photographs showed non-significant shrinkage in the vertical and horizontal dimensions (P=0.575 and P=0.444, respectively). The new bone contained vital bone cells embedded in mineralized tissues. CONCLUSIONS: Within the limitations of this pilot study, open healing of RCLC membranes may result in sufficient bone volume for implant placement without additional bone augmentation in contained and non-contained extraction sockets.