Daniel B. Spagnoli

Pivotal, Randomized, Parallel Evaluation of Recombinant Human Bone Morphogenetic Protein-2/Absorbable Collagen Sponge and Autogenous Bone Graft for Maxillary Sinus Floor Augmentation

PURPOSE The purpose of this prospective study was to evaluate the safety and effectiveness of recombinant human morphogenetic protein-2 (rhBMP-2) on an absorbable collagen sponge (ACS) compared with an autogenous bone graft when used for 2-stage maxillary sinus floor augmentation. The study assessed new bone formation, placement integration, and functional loading after 6 months and long term for 2 years. MATERIALS AND METHODS A total of 160 subjects were randomized, enrolled, and followed from January 1999 to February 2004 at 21 centers in the United States. The subjects with less than 6 mm of native bone height were treated with 1.50 mg/mL rhBMP-2/ACS or with an autograft. The height and density measurements were quantified by computed tomography scans. Core biopsies were obtained at dental implant placement and used for histological analysis. Safety was evaluated by oral examinations, radiographs, serum chemistries, and hematology. RESULTS A significant amount of new bone was formed by 6 months postoperatively in each group. The mean change in bone height in the rhBMP-2/ACS subjects was 7.83 +/- 3.52 mm versus 9.46 +/- 4.11 mm for the bone graft subjects. At 6 months after dental restoration, the induced bone in the rhBMP-2/ACS group was significantly denser than that in the bone graft group. No marked differences were found in the histologic parameters evaluated between the 2 groups. The new bone was comparable to the native bone in density and structure in both groups. The success rate for the rhBMP-2/ACS group was 79% (64 of 81 subjects), and 201 of 251 implants placed in the bone graft group and 199 of 241 implants placed in the rhBMP-2/ACS group were integrated, retained, and functional at 6 months after loading. No adverse events were deemed related to the rhBMP-2/ACS treatment. The autograft group was noted to have a 17% rate of long-term parasthesia, pain, or gait disturbance related to the bone graft harvest. CONCLUSIONS The results of our multicenter, randomized, prospective, clinical trial have shown the effectiveness and safety of rhBMP-2/ACS compared with bone graft for sinus floor augmentation. The studys primary endpoint was exceeded, and the implants placed in rhBMP-2/ACS and bone graft groups performed similarly after functional loading.

Dental Implants and the Use of rhBMP-2

Tissue engineering is an emerging field of medicine and dentistry that combines the bodys natural biologic response to tissue injury with engineering principles. The goal is to replicate or reconstruct the natural form and function of missing tissues and organs. Tissue-engineered bone with native qualities will be necessary for implantation or migration of engineered teeth in the future, and is currently required for the osseointegration of dental implants. This article addresses the role of bone morphogenetic proteins (BMP) in native bone healing for implant osseointegration and the application of BMP for de novo bone regeneration.

Extraction Socket Grafting and Buccal Wall Regeneration with Recombinant Human Bone Morphogenetic Protein-2 and Acellular Collagen Sponge

The natural evolution of the extraction socket is one of bone loss, most significantly affecting the buccal-lingual dimension. The healing socket regenerates through intramembranous ossification. The newly developed bone undergoes remodeling and responds to mechanical stress (modeling). The load created by a dental implant leads to long-term modeling of the bone. Allograft, xenograft, or alloplast grafts are static, inert materials often found unresorbed in graft sites. Residual graft particles that do not resorb can interfere with stressand strain-induced bone modeling. Bone morphogenetic protein-2 (BMP-2) is a cytokine member of the transforming growth factor b superfamily that stimulates de novo bone formation. Recombinant human BMP-2 (rhBMP-2) (1.5 mg/mL) delivered via an acellular collagen sponge (ACS) is a versatile graft that can be used alone, in conjunction with mineralized cancellous particles, and with simultaneous implant placement. Implants placed in extraction sockets act as a construct to enhance bone regeneration. In the author’s experience, implants placed in sockets with wall defects and grafting with rhBMP-2/ACS have shown excellent integration and buccal wall regeneration. When implant placement is not feasible, socket preservation screws can be used to support gingiva and regenerate alveolar form while maintaining biologic width.

Tissue engineering for lateral ridge augmentation with recombinant human bone morphogenetic protein 2 combination therapy: a case report.

This case report describes a tissue-engineered reconstruction with recombinant human bone morphogenetic protein 2/acellular collagen sponge (rhBMP-2/ ACS) + cancellous allograft and space maintenance via Medpor Contain mesh in the treatment of a patient requiring maxillary and mandibular horizontal ridge augmentation to enable implant placement. The patient underwent a previously unsuccessful corticocancellous bone graft at these sites. Multiple and contiguous sites in the maxilla and in the mandibular anterior, demonstrating advanced lateral ridge deficiencies, were managed using a tissue engineering approach as an alternative to autogenous bone harvesting. Four maxillary and three mandibular implants were placed 9 and 10 months, respectively, after tissue engineering reconstruction, and all were functioning successfully after 24 months of follow-up. Histomorphometric analysis of a bone core obtained at the time of the maxillary implant placement demonstrated a mean of 76.1% new vital bone formation, 22.2% marrow/cells, and 1.7% residual graft tissue. Tissue engineering for lateral ridge augmentation with combination therapy requires further research to determine predictability and limitations.

Tissue Engineering for Vertical Ridge Reconstruction

This article provides an overview of basic tissue engineering principles as they are applied to vertical ridge defects and reconstructive techniques for these types of deficiencies. Presented are multiple clinical cases ranging from office-based dentoalveolar procedures to the more complex reconstruction of postresection mandibular defects. Several different types of regenerative tissue constructs are presented; either used alone or in combination with traditional reconstructive techniques and procedures, such as maxillary sinus augmentation, Le Fort I osteotomy, and microvascular free tissue transfer. The goal is to also familiarize the reconstructive surgeon to potential future strategies in vertical alveolar ridge augmentation.

Bifocal Distraction in Patient with Rheumatoid Arthritis and Severe Condylar Degeneration: Report of Case

El compromiso facial en pacientes con artritis reumatoide es variable dependiendo del inicio, tipo y duracion de la enfermedad. El tratamiento del paciente con mordida abierta resultante de procesos degenerativos condilares son desafiantes para los cirujanos. La artritis reumatoide es una enfermedad sistemica de etiologia desconocida caracterizada por inflamacion cronica y proliferacion del tejido sinovial. Algunos estudios han demostrado que pacientes con artritis reumatoide pueden desarrollar osteoartrosis progresiva que resulta en importantes cambios condilares. Con el desarrollo de la distraccion osteogenica para el tratamiento de la hipoplasia mandibular se abrio un nuevo capitulo en el manejo quirurgico de pacientes con artritis reumatoide asociada a deficiencias esqueletales. El objetivo de este articulo es evaluar la aplicacion de distraccion osteogenica en un caso de mordida abierta anterior en paciente con artritis reumatoide y degeneracion condilar severa.

Biologics and Cell Therapy Tissue Engineering Approaches for the Management of the Edentulous Maxilla: A Systematic Review.

PURPOSE The aim of this systematic review was to evaluate current and emerging regenerative approaches for implant site development in the edentulous atrophic maxilla using tissue engineering and regenerative medicine (TERM) principles and to identify priorities for future research. MATERIALS AND METHODS Two independent examiners conducted a comprehensive search using specific keywords to identify original clinical studies using TERM for implant site development in the edentulous atrophic maxilla including indications for alveolar ridge preservation, horizontal alveolar augmentation, maxillary sinus augmentation, and augmentation of severe vertical or combined defects. Endpoints included clinical, radiographic, histologic, and patient-centered outcomes. RESULTS The initial search identified 3,061 articles. The final selection included 89 articles, of which 12 evaluated alveolar ridge preservation, 6 horizontal defects, 61 maxillary sinus augmentation, and 11 management of severe vertical or combined defects. A summary of the main findings relative to the effect of TERM-based approaches applied for implant site development in the atrophic maxillary segments is presented. Marked heterogeneity among included studies prevented meaningful quantitative analysis. The following relevant effects of TERM-based therapies for site development in the edentulous atrophic maxilla were observed: (1) recombinant human bone morphogenetic protein-2 in an absorbable collagen sponge carrier increased bone augmentation; (2) recombinant human platelet-derived growth factor BB in combination with freeze-dried bone allograft or beta tricalcium phosphate accelerated bone formation through accelerated remodeling of carrier biomaterials; (3) autologous cell therapy enhanced clinical and radiographic outcomes; (4) autologous cell therapy in alveolar ridge preservation provided superior histomorphometric outcomes (vital bone formation) at 6 weeks; and (5) platelet-rich plasma formulations combined with autologous bone grafts for maxillary sinus augmentation increased radiographic density and accelerated bone mineralization at 6 months. CONCLUSION Clinical success has been demonstrated with the application of different TERM modalities for implant site development in the edentulous atrophic maxilla. However, indications are narrow and further study is needed. Clinical trials assessing meaningful outcomes, involving larger populations, and with longer follow-up are warranted to discern the effectiveness of the achieved results compared with a valid control.

Preemptive Analgesia and Multimodal Pain Management for Temporomandibular Total Joint Replacement Surgery

Pain is a complex experience and not a single entity. Postoperative pain in patients undergoing temporomandibular joint replacement occurs due to several reasons.