A preliminary report on the effect of dimeric rhGDF-5 and its monomeric form rhGDF-5C465A on bone healing of rat cranial defects

Applications of Bone Morphogenetic Proteins in Dentistry: A Bibliometric Analysis

Background

Many articles on bone morphogenetic proteins (BMPs) have been published. Bibliometric analysis is helpful to determine the most influential studies in a specific field. This bibliometric analysis is aimed at identifying and analyzing the top 50 most-cited articles on the dental applications of BMPs.

Methods

An electronic search was conducted using the Web of Science (WoS) “All Databases” without any restriction of language, study design, or publication year. Of 1341 publications, the top 50 were included based on their citation count. After downloading the full texts, their bibliometric data including publication title, authorship, citation count, current citation index 2019, citation density, year of publication, country and institution of origin, journal of publication, type of BMP, study design, evidence level of publication, and keywords were extracted and analyzed.

Results

The citation counts for the top 50 publications ranged from 81 to 557 (median 113.5). The most prolific year was 1997 (n = 7). Wikesjö UM (n = 12) and Wozney JM (n = 11) were the major contributors in this study. Most of the articles were generated primarily from the USA (n = 24), with Loma Linda University Medical Center, USA being the most prolific institution (n = 5). Majority of the articles were published in the Clinical Oral Implants Research and Journal of Periodontology, with nine publications each. Most of the publications were animal studies (n = 30) and focused on BMP-2 (n = 39). Most of the articles were within evidence level V (n = 36). The most frequently used keyword in the top articles was “bone regeneration” (n = 23).

Conclusion

The present study presents insights into the past and recent trends in the applications of BMPs in dentistry. A statistically significant association was observed between citation count, citation density, and age of publication.

Immunohistochemistry evaluation of BMP-2 with β-tricalcium phosphate matrix, polylactic and polyglycolic acid gel, and calcium phosphate cement in rats

PURPOSE

The installation of implants has become a routine procedure in the clinic. However, it takes time and adequate bone thickness, and for that, tissue engineering has made efforts to develop substitutes for autografts, in view of certain disadvantages of this material. The decision to choose the most suitable graft material for each case is an important step in the success of bone reconstruction. This study was to verify, by means of immunohistochemical study, that the addition of bone morphogenetic protein had some influence on biomaterials commercially available, taking into account the formation of mineralized tissue, bone replacement, and the amount of degradation of biomaterials.

METHODS

The sample consisted of 72 rats that were divided into eight treatment groups, in which two defects of 5 mm were made in each animal calvaria. Euthanasia was performed at 5, 15, and 30 days postop.

RESULTS

A histologic and histometric analysis was performed to quantitate the area of mineralized tissue formed, the area of newly formed bone, and the area of degradation of the biomaterials. Data were analyzed with multiple comparisons of means by Tukey contrasts, and significant difference was assigned at the level of P < 0.05. The proteins used for immunohistochemical analysis accounted for the process of formation, mineralization, and bone resorption and was performed using ordinal qualitative analysis, where from assigning scores.

CONCLUSIONS

Bone morphogenetic protein 2 was shown to be effective as an inducer of bone formation process independent biomaterial used mainly for accelerating the resorption process of the framework.

Improved bone defect healing by a superagonistic GDF5 variant derived from a patient with multiple synostoses syndrome

Multiple synostoses syndrome 2 (SYNS2) is a rare genetic disease characterized by multiple fusions of the joints of the extremities, like phalangeal joints, carpal and tarsal joints or the knee and elbows. SYNS2 is caused by point mutations in the Growth and Differentiation Factor 5 (GDF5), which plays an essential role during skeletal development and regeneration. We selected one of the SYNS2-causing GDF5 mutations, p.N445T, which is known to destabilize the interaction with the Bone Morphogenetic Protein (BMP) antagonist NOGGIN (NOG), in order to generate the superagonistic GDF5 variant GDF5(N445T). In this study, we tested its capacity to support regeneration in a rat critical-sized defect model in vivo. MicroCT and histological analyses indicate that GDF5(N445T)-treated defects show faster and more efficient healing compared to GDF5 wild type (GDF5(wt))-treated defects. Microarray-based gene expression and quantitative PCR analyses from callus tissue point to a specific acceleration of the early phases of bone healing, comprising the inflammation and chondrogenesis phase. These results support the concept that disease-deduced growth factor variants are promising lead structures for novel therapeutics with improved clinical activities.

Biocomposite cryogels as tissue-engineered biomaterials for regeneration of critical-sized cranial bone defects

Analysis of the in vivo regeneration capability of any tissue-engineered biomaterial is necessary once it shows potential characteristics during in vitro studies. Thus, we applied polyvinyl alcohol-tetraethylorthosilicate-alginate-calcium oxide (PTAC) biocomposite cryogel on critical-sized cranial bone defects in wistar rats for examining the comparative bone regeneration of cryogel-treated and nontreated defects over a period of 4 weeks. An in-depth analysis was performed from macroscopic level till the gene level. Bone regeneration in cryogel-treated defects was clearly evident from the results, whereas the nontreated group did not show any defect healing except at few peripheral areas. At the macroscopic level, micro-computed tomography analysis revealed new bone formation. This was further confirmed at the cellular level, wherein, new bone formation was demonstrated by hematoxylin and eosin staining. Osteoblastic differentiation was further validated by immunohistological staining of runt-related transcription factor-2 (Runx-2) protein and via calcium-phosphate crystal formation after 2 weeks through scanning electron microscopy and energy dispersive X-ray spectroscopy. Finally, at the gene level, real-time PCR analysis confirmed the mRNA expression of osteoblastic markers, that is, runx-2, collagen type I (Col I), alkaline phosphatase (ALP), and osteocalcin (OCN). Therefore, the results of in vivo cranial defect model studies suggest that PTAC biocomposite cryogels can show suitable potential for human bone regeneration.

Current Approaches of Bone Morphogenetic Proteins in Dentistry

Bone morphogenic proteins (BMPs) are a group of osteoinductive proteins obtained from nonmineralized bone matrix; they are capable of stimulating the differentiation of pluripotent mesenchymal cells to osteoprogenitor cells. They have become a likely treatment option, given their action on regeneration and remodeling of bone lesions and increasing the bone response around alloplastic materials. It may be feasible in the near future for BMPs to replace autologous and allogenic bone grafts. The application of specific growth factors for osteoinduction without using a bone graft constitutes a real impact on bone regeneration. The use of BMP is not only focused on osteogenic regeneration: There are a variety of studies investigating other properties, such as periodontal or dental regeneration from the conservative viewpoint. In this review, we will highlight the role of the BMP in bone, periodontal and dental regeneration.

Biomaterial delivery of morphogens to mimic the natural healing cascade in bone

Complications in treatment of large bone defects using bone grafting still remain. Our understanding of the endogenous bone regeneration cascade has inspired the exploration of a wide variety of growth factors (GFs) in an effort to mimic the natural signaling that controls bone healing. Biomaterial-based delivery of single exogenous GFs has shown therapeutic efficacy, and this likely relates to its ability to recruit and promote replication of cells involved in tissue development and the healing process. However, as the natural bone healing cascade involves the action of multiple factors, each acting in a specific spatiotemporal pattern, strategies aiming to mimic the critical aspects of this process will likely benefit from the usage of multiple therapeutic agents. This article reviews the current status of approaches to deliver single GFs, as well as ongoing efforts to develop sophisticated delivery platforms to deliver multiple lineage-directing morphogens (multiple GFs) during bone healing.

Bone morphogenic protein: an elixir for bone grafting--a review

Bone morphogenetic proteins (BMPs) are multifunctional growth factors that belong to the transforming growth factor beta superfamily. This literature review focuses on the molecular biology of BMPs, their mechanism of action, and subsequent applications. It also discusses uses of BMPs in the fields of dentistry and orthopedics, research on methods of delivering BMPs, and their role in tissue regeneration. BMP has positive effects on bone grafts, and their calculated and timely use with other growth factors can provide extraordinary results in fractured or nonhealing bones. Use of BMP introduces new applications in the field of implantology and bone grafting. This review touches on a few unknown facts about BMP and this ever-changing field of research to improve human life.

Bone morphogenetic proteins in orthopaedic surgery

Bone healing is a predictable process that has a high rate of success. For some patients, and in certain clinical settings, this process can be delayed or completely inhibited. This leads to significant morbidity and may also result in time lost from work, costs related to prolonged medical treatment, and continued pain at the site of nonunion or failed spinal fusion. Several growth factors, specifically BMP-2 and BMP-7, have been approved in several countries for specific indications. The use of these products and potential complications of their use are reviewed.