Marco Cicciù

Recombinant human bone morphogenetic protein-2 promote and stabilize hard and soft tissue healing for large mandibular new bone reconstruction defects

AbstractNumerous autogenous bone-grafting procedures are available for the recovering of large continuity defects of the mandible. However, these surgical techniques present several limitations involving postoperative morbidity and pain. The development of new bone technique reconstruction not involving autogenous bone graft would offer new opportunities for facial bone reconstruction.This report highlights the possibility of recombinant human bone morphogenetic protein type 2 (rhBMP-2) application without concomitant bone grafting material in the restoration of continuity critical-sized defects after tumor resection in the mandible. The presented case shows a large mandibular reconstruction after tumor removal in a 31-year-old white man affected by ameloblastoma.In this case, the rhBMP-2 application with a carrier consisted on absorbable collagen sponge gives excellent newly formed bone at 18 months of control clinical and radiologic follow-up.The results indicated that the use of rhBMP-2 without concomitant autogenous bone grafting materials in large critical-sized mandibular defects secondary to large mandibular tumor produced excellent regeneration of the treated area.

Immediate distraction osteogenesis: the sandwich technique in combination with rhBMP-2 for anterior maxillary and mandibular defects.

AbstractThe goal of this study was to demonstrate the technique and effectiveness of incorporating recombinant human bone morphogenetic protein-2 (rhBMP-2) to the established sandwich osteotomy technique. Although the success of the sandwich osteotomy procedure has been well documented, we hope to show that the addition of rhBMP-2 will enhance bone formation.We performed a sandwich osteotomy technique in patients who had been treated initially by grafting with suboptimal results. Only defects involving the anterior maxilla (3 patients) or the anterior mandible (1 patient) were included. There were 4 patients, 2 men and 2 women, with an age range of 19 to 62 years. The causes of the ridge deficiencies ranged from pathology to trauma. The height (distance) of distracted transport bone segment was measured. The amount of relapse was measured 6 months after the surgery.All patients exhibited a significant increase in bone height. The amount distracted was 6.75 mm (range, 5–11 mm). The amount of relapse was 8.5% (range, 0%–18%). Dental implants were placed in the reconstructed ridges in all patients. There were no instances of permanent paresthesia. Two patients had exposure of a portion of the hardware, which healed uneventfully.The sandwich osteotomy technique has proven to be an effective method for augmenting deficient alveolar ridges. The addition of rhBMP-2 may aid in its success rate by promoting osteogenesis at the osteotomy site, especially in multiple-operated patients where other traditional techniques have failed to gain the desired ridge height.

Vertical ridge augmentation of the atrophic posterior mandible with sandwich technique: bone block from the chin area versus corticocancellous bone block allograft--clinical and histological prospective randomized controlled study.

The aim of the present study is to compare the histological aspects of bone formation in atrophic posterior mandibles augmented by autologous bone block from chin area with corticocancellous bone block allograft used as inlays with the sandwich technique. Materials and Methods. Sixteen patients with bilateral partial edentulism in the posterior mandible were selected. The residual bone height, preliminarily measured by computed tomography scans, ranged between 5 and 7 mm from the inferior alveolar nerve. All patients required regeneration procedure with autologous bone block from chin area (control group) versus bone block allograft Puros (Zimmer Dental, 1900 Aston Avenue, Carlsbad, CA, USA) (test group). Histological and histomorphometric samples were collected at the time of implant positioning in order to analyze the percentage of newly formed bone, the residual graft material, and marrow spaces/soft tissue. Results. No statistically significant differences between the two groups were found regarding the percentage of newly formed bone. The percentage of residual grafted material was significantly higher in the test group, whilst the percentage of marrow spaces was higher in control group. Conclusions. In conclusion, both procedures supported good results, although the use of bone blocks allograft was less invasive and preferable than harvesting bone from the mental symphysis.

Recombinant human bone morphogenetic protein type 2 application for a possible treatment of bisphosphonates-related osteonecrosis of the jaw.

Abstract Bisphosphonates are a class of agents used for treating osteoporosis and malignant bone metastases treatment. Osteonecrosis of the jaws is the main complication in a subset of patients receiving these drugs. Based on a growing number of case reports and institutional reviews, bisphosphonate therapy can cause exposed and necrotic bone that is isolated to the jaw. This clinical investigation is aimed at analyzing the clinical effect of recombinant human bone morphogenetic protein type 2 (rhBMP-2) application in patients affected by bisphosphonates-related osteonecrosis of the jaws undergoing surgery for necrotic bone removal. A case review was made of 20 patients. The rhBMP-2 in all the cases reported here was used alone with the collagen carrier without concomitant bone materials. The cases involved osteonecrotic lesions of the upper and lower jaws. A total dose of 4 to 8 mg of rhBMP-2 was delivered to the surgical site in concentrations of 1.5 mg/mL (depending on the size of lesion). Patients were followed up over a period ranging 6 to 12 months. Patients had successful healing of the necrotic area. New bone formation in the surgical area could be clinically evaluated by palpation at the end of 3 to 4 months and confirmed by radiographic examination at the end of 12 months. This study indicated that the use of rhBMP-2 without concomitant bone grafting materials was useful in promoting healing of bisphosphonates-related osteonecrosis of the jaws. The use of growth factors, particularly rhBMP-2, should be considered a therapeutic choice in patients affected by osteonecrosis of the jaws related to bisphosphonate therapy.

Use of a Porcine Collagen Matrix as an Alternative to Autogenous Tissue for Grafting Oral Soft Tissue Defects

PURPOSE Soft tissue grafting is often required to correct intraoral mucosal deficiencies. Autogenous grafts have disadvantages including an additional harvest site with its associated pain and morbidity and, sometimes, poor quality and limited amount of the graft. Porcine collagen matrices have the potential to be helpful for grafting of soft tissue defects. PATIENTS AND METHODS Thirty consecutive patients underwent intraoral grafting to re-create missing soft tissue. Defects ranged in size from 50 to 900 mm(2). Porcine collagen matrices were used to reconstruct missing tissue. Indications included preprosthetic (22), followed by tumor removal (5), trauma (2), and release of cheek ankylosis (1). RESULTS The primary efficacy parameters evaluated were the degree of lateral and/or alveolar extension and the evaluation of re-epithelialization and shrinkage of the grafted area. Overall, the percentage of shrinkage of the graft was 14% (range, 5%-20%). The amount of soft tissue extension averaged 3.4 mm (range, 2-10 mm). The secondary efficacy parameters included hemostatic effect, pain evaluation, pain and discomfort, and clinical evaluation of the grafted site. All patients reported minimal pain and swelling associated with the grafted area. No infections were noted. CONCLUSION This porcine collagen matrix provides a biocompatible surgical material as an alternative to an autogenous transplant, thus obviating the need to harvest soft tissue autogenous grafts from other areas of the oral cavity.

Recombinant human bone morphogenetic protein type 2 jaw reconstruction in patients affected by giant cell tumor.

Giant cell tumor (GCT) is a relatively common skeletal tumor. Mandibular localization of this tumor is usually treated with resection of the tumor area. Several autogenous bone-grafting techniques are available for the restoration of large continuity defects of the mandible. However, these procedures are associated with limitations involving postoperative morbidity, difficulty in ambulation (hip graft), and pain. The development of a technique of surgical reconstruction not involving autogenous bone would offer new opportunities for facial bone reconstruction, particularly of the mandible. This study aims to underline the effect of recombinant human bone morphogenetic protein type 2 (rhBMP-2) in a collagen carrier with concomitant bone grafting material in the restoration of continuity critical-size defects after GCT resection in the mandible. The rhBMP-2 was used with absorbable collagen sponge. A total dose of 4 to 8 mg of rhBMP-2 was delivered to the surgical site in concentrations of 1.5 mg/mL. The patient was followed up over a period from 6 to 18 months. Occlusal function was initially restored with conventional prosthesis. Bone formation in the surgical area could be palpated at the end of 3 to 4 months and identified radiographically at the end of 5 to 6 months. The results clearly indicated that the use of rhBMP-2 without concomitant bone grafting materials in large critical-size mandibular defects secondary to GCT produced excellent regeneration of the area, establishing the basis for the return of prosthodontic function.

Bisphosphonate-Associated Osteonecrosis of the Jaw in Patients with Multiple Myeloma and Breast Cancer

Osteonecrosis of the jaw is an unremitting adverse outcome associated with bisphosphonate therapy in patients with multiple myeloma or bone metastases from solid tumors. Twelve patients who presented with exposed bone associated with bisphosphonates were reviewed to determine the type, dosage and duration of their bisphosphonate therapy, presenting findings, comorbidities and the event that incited the bone exposure. The discontinuation of bisphosphonate therapy has not helped reverse the presence of osteonecrosis, and the surgical manipulation of the involved site appears to worsen the underlying bone pathology. Hyperbaric oxygen, which has proven efficacious in other forms of osteonecrosis by establishing an oxygen gradient, is of no definitive benefit to patients with bisphosphonate-induced exposed bone. Antibiotic therapy is useful in controlling pain and swelling but ineffective in preventing the progression of the exposed bone. To date, prevention is the only currently possible therapeutic approach to the management of this complication.

Histomorphometric Evaluation of Anorganic Bovine Bone Coverage to Reduce Autogenous Grafts Resorption: Preliminary Results

Physiologic resorption due to remodeling processes affects autogenous corticocancellous grafts in the treatment of atrophic jawbone alveolar ridges. Such a situation in the past made overgrafting of the recipient site mandatory to get enough bone support to dental implants in order to perform a prosthetic rehabilitation. Anorganic bovine bone, conventionally used to treat alveolar bone deficiencies in implant surgery, showed a high osteoconductive property thanks to its micro and macrostructure very similar to that of human hydroxyapatite. An original technique provides for the application of a thin layer of anorganic bovine bone granules and a collagen membrane on the top of the corticocancellous onlay bone grafts to reduce in a remarkable way the graft resorption due to remodeling. The results of a clinical prospective study and a histomorphometric analysis done on autogenous grafts harvested from the iliac crest showed that the proposed technique is able to maintain the original bone volume of the corticocancellous blocks.

Protein-Signaled Guided Bone Regeneration Using Titanium Mesh and Rh-BMP2 in Oral Surgery: A Case Report Involving Left Mandibular Reconstruction after Tumor Resection

Recombinant human bone morphogenetic protein-2 (rhBMP-2) is an osteoinductive protein approved for use in oral and maxillofacial defect reconstruction. Growth factors act as mediators of cellular growth on morphogenesis and mythogenesis phases. Utilized as recombinant proteins, these growth factors need the presence of local target cells capable of obtaining the required results. This cell population may be present at the wound site or added to scaffolding material before implantation at the surgical site. The aim of this study is to evaluate the clinical and radiographic results of a reported case with a large bone defect, treated with an absorbable collagen sponge, rhBMP-2 and a titanium plate and mesh. The Authors want to report a case which shows the resulting effectiveness of the rhBMP2 action regarding a large, mandibular defect reconstruction. This case also shows how the removal of a rare tumor such as a ghost cell tumor of the jaw may be treated without harvesting bone from another body site. A quick diagnosis of the lesions is important in order to perform the most suitable treatment. The Authors also underline the clinical and histological steps to insure the correct treatment is carried out to solve the case. Moreover, from results obtained from this case, it is possible to highlight several clinical benefits for the patient by adding rhBMP-2 to the common allograft to not only have alveolar reconstruction defects and sinus floor augmentation, but also to have alveolar cleft reconstruction and to treat segmental defects.

Schneider membrane elevation in presence of sinus septa: Anatomic features and surgical management

Maxillary sinus floor elevation via a lateral approach is a predictable technique to increase bone volume of the edentulous posterior maxilla and consequently for dental implants placement. The sinus floor is elevated and it can be augmented with either autologous or xenogeneic bone grafts following an opening bone window created on the facial buccal wall. Maxillary septa are walls of cortical bone within the maxillary sinus. The septa shape has been described as an inverted gothic arch arising from the inferior or lateral walls of the sinus and may even divide the sinus into two or more cavities. Some authors have reported a higher prevalence of septa in atrophic edentulous areas than in nonatrophic ones. Radiographic identification of these structures is important in order to perform the right design of the lateral window during sinus lift. Aim of this investigation is to highlight the correct steps for doing sinus lift surgery in presence of those anatomic variations. Clinicians should always perform clinical and radiographic diagnosis in order to avoid complications related to the sinus lift surgery.