The use of a collagenated porcine cortical lamina in the reconstruction of alveolar ridge defects. A clinical and histological study.

BACKGROUND: Alveolar ridge reconstruction by means of resorbable and non-resorbable membranes has been proposed to increase the hard tissue volume in deficient sites. The purpose of this study was therefore to clinically and histologically evaluate the use of collagenated porcine bone lamina in case of horizontal and vertical bone augmentation procedures in conjunction with particulate porcine xenograft. METHODS: Overall, 8 partially edentulous patients (6 females and 2 males) with a mean age of 45 years requiring bone regeneration procedures to achieve a prosthetically driven implant placement were enrolled. All ridge defects were augmented using a xenogeneic cortical bone barrier in combination with particulate heterologous bone. Bone biopsies were collected during the re-entry procedure. RESULTS: A total of 15 implants were placed both simultaneously or in a staged approach in the augmented sites. No complications occurred during the rehabilitation. Histologically, the bone lamina was widely vascularized and integrated with the surrounding soft tissues and the native bone. The presence of osteoclastic lacunae suggested an active remodeling of the particulate graft and a gradual substitution with the newly formed bone. CONCLUSIONS: Alveolar reconstruction by means of the collagenated cortical lamina gave promising clinical and histological results. The rigidity and the slow resorption pattern allowed for the blood clot protection even in case of vertical defects, avoiding at the same time the re-entry surgery for its removal.

Alveolar ridge augmentation with titanium mesh. A retrospective clinical study.

An adequate amount of bone all around the implant surface is essential in order to obtain long-term success of implant restoration. Several techniques have been described to augment alveolar bone volume in critical clinical situations, including guided bone regeneration, based on the use of barrier membranes to prevent ingrowth of the epithelial and gingival connective tissue cells. To achieve this goal, the use of barriers made of titanium micromesh has been advocated. A total of 13 patients were selected for alveolar ridge reconstruction treatment prior to implant placement. Each patient underwent a tridimensional bone augmentation by means of a Ti-mesh filled with intraoral autogenous bone mixed with deproteinized anorganic bovine bone in a 1:1 ratio. Implants were placed after a healing period of 6 months. Panoramic x-rays were performed after each surgical procedure and during the follow-up recalls. Software was used to measure the mesial and the distal peri-implant bone loss around each implant. The mean peri-implant bone loss was 1.743 mm on the mesial side and 1.913 mm on the distal side, from the top of the implant head to the first visible bone-implant contact, at a mean follow-up of 88 months. The use of Ti-mesh allows the regeneration of sufficient bone volume for ideal implant placement. The clinical advantages related to this technique include the possibility of correcting severe vertical atrophies associated with considerable reductions in width and the lack of major complications if soft-tissue dehiscence and mesh exposures do occur.

Histomorphometrical evaluation of fresh frozen bone allografts for alveolar bone reconstruction: preliminary cases comparing femoral head with iliac crest grafts.

PURPOSE: In the past few years, the use of fresh frozen bone (FFB) grafts has significantly increased. The aim of this study was to evaluate the reconstruction of alveolar bone using femoral head and iliac crest FFB grafts. MATERIALS AND METHODS: The study included 10 patients who need endosseous implant insertion in severe atrophic maxillae. The patients were treated with FFB grafts collected from the femoral head or iliac crest. Bone regeneration was evaluated 6 months after surgery by macroscopic and microscopic analyses. RESULTS: Our results showed good regenerative capacity, both with the FFB from the femoral head and iliac crest. In particular, similar percentages of new-bone formation and graft residual were observed, whereas differences between the percentage of total bone (higher for the iliac crest) and the percentage of non-mineralized tissue (higher for the femoral head) were present. A significantly higher percentage of CD34-positive vessels in the FFB allograft from the femoral head than in the iliac crest were observed. CONCLUSIONS: These findings suggest that FFB allografts could represent a reliable option in oral and maxillofacial surgery. Nevertheless, differences between the use of femoral head or iliac crest bone allografts linked with their different structures should be considered for a more effective surgery.