Bone Regeneration in Athymic Calvarial Defects With Accell DBM100

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.

Comparative study of chitosan/fibroin-hydroxyapatite and collagen membranes for guided bone regeneration in rat calvarial defects: micro-computed tomography analysis

This study aimed to utilize micro-computed tomography (micro-CT) analysis to compare new bone formation in rat calvarial defects using chitosan/fibroin-hydroxyapatite (CFB-HAP) or collagen (Bio-Gide) membranes. Fifty-four (54) rats were studied. A circular bony defect (8 mm diameter) was formed in the centre of the calvaria using a trephine bur. The CFB-HAP membrane was prepared by thermally induced phase separation. In the experimental group (n=18), the CFB-HAP membrane was used to cover the bony defect, and in the control group (n=18), a resorbable collagen membrane (Bio-Gide) was used. In the negative control group (n=18), no membrane was used. In each group, six animals were euthanized at 2, 4 and 8 weeks after surgery. The specimens were then analysed using micro-CT. There were significant differences in bone volume (BV) and bone mineral density (BMD) (P<0.05) between the negative control group and the membrane groups. However, there were no significant differences between the CFB-HAP group and the collagen group. We concluded that the CFB-HAP membrane has significant potential as a guided bone regeneration (GBR) membrane.

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.

The comparative effectiveness of demineralized bone matrix, beta-tricalcium phosphate, and bovine-derived anorganic bone matrix on inflammation and bone formation using a paired calvarial defect model in rats

BACKGROUND

In this study, the effectiveness of Iranian Tissue Bank-produced demineralized bone matrix (ITB-DBM), beta-tricalcium phosphate (βTCP), and Bio-Oss(®) (Geistlich Pharma AG, Wolhusen, Switzerland) were evaluated and compared with double controls. The main goal was to measure the amount of new bone formation in the center of defects created in rat calvaria. Another goal was to compare the controls and evaluate the effects of each treatment material on their adjacent untreated (control) defects.

METHODS

In this study, 40 male Wistar rats were selected and divided into four groups, In each group, there were ten rats with two defects in their calvarias; one of them is considered as control and the other one was treated with ITB-DBM (group 1), BIO-OSS (group2), and βTCP (group 3), respectively. But in group 4, both defects were considered as control. The amount of inflammation and new bone formation were evaluated at 4 and 10 weeks. In the first group, one defect was filled with ITB-DBM; in the second group, one defect was filled with Bio-Oss; in the third group, one defect was filled with βTCP; and in the fourth group, both defects were left unfilled. Zeiss microscope (Carl Zeiss AG, Oberkochen, Germany) and Image Tool(®) (version 3.0; University of Texas Health Science Center at San Antonio, San Antonio, TX) software were used for evaluation. SPSS Statistics (IBM Corp, Somers, NY) was used for statistical analysis.

RESULTS

Maximum bone formation at 4 and 10 weeks were observed in the ITB-DBM group (46.960% ± 4.366%, 94.970% ± 0.323%), which had significant difference compared with the other groups (P < 0.001). Ranking second was the Bio-Oss group and third, the βTCP group. Bone formation in the group with two unfilled defects was much more significant than in the other controls beside the Bio-Oss and βTCP after 10 weeks (29.1 ± 2.065, 29.05 ± 1.649), while this group had the least bone formation compared with the other controls at week 4 (2.100% ± 0.758%, 1.630% ± 0.668%, P < 0.001).

CONCLUSION

Overall, the ITB-DBM group showed the best results, although the results for other experimental groups were unfavorable. The authors conclude that human DBM (ITB-DBM) should be offered as an alternative for bone regeneration in animals, such as horses, as well as in humans, especially for jaw reconstruction. In relation to bone regeneration in control defects, the effect of experimental material on controls was apparent during the initial weeks.

In vitro and in vivo evaluation of osteogenesis of human umbilical cord blood-derived mesenchymal stem cells on partially demineralized bone matrix

The osteogenic differentiation potential of umbilical cord blood-derived mesenchymal stem cells (UCB-MSCs) has been documented previously, and partially demineralized bone matrix (pDBM) represents a promising candidate for bone tissue engineering scaffolds. In this study, pDBM scaffolds derived from porcine cancellous bone were evaluated for their ability to support human UCB-MSCs osteogenic differentiation in vitro and bone-forming capacity in vivo to assess the potential use of UCB-MSCs in bone tissue engineering applications. MSCs were isolated from full-term human UCB and expanded, and their cell surface antigen markers and multilineage capability to differentiate into osteoblasts, chondrocytes, and adipocytes were analyzed. The in vitro proliferation and osteogenic differentiation of UCB-MSCs loaded onto the three-dimensional pDBM scaffolds were determined. Critical-sized full-thickness circular defects (5 mm in diameter) created bilaterally in the parietal bones of athymic rats were treated with one of the following: osteogenically induced UCB-MSC/pDBM composites (Group A, n = 8), noninduced UCB-MSC/pDBM composites (Group B, n = 8), pDBM alone (Group C, n = 8), or left untreated (Group D, n = 8). Microcomputed tomography analysis showed that new bone was formed in Group A at 6 weeks postimplantation, and greater bone volume and density were found after 12 weeks. In other groups, new bone formation was not evident after 6 weeks, and no bone union was found at 12 weeks. Histological examination revealed that the defect was repaired by tissue-engineered bone in Group A at 12 weeks, and fibrous union was observed in Groups B, C, and D. These results demonstrate that pDBM can support osteogenic differentiation of human UCB-MSCs in vitro and in vivo, and UCB-MSCs may serve as an alternative cell source for bone tissue engineering and regeneration.

Extremely small-magnitude accelerations enhance bone regeneration: a preliminary study

High-frequency, low-magnitude accelerations can be anabolic and anticatabolic to bone. We tested the hypothesis that application of these mechanical signals can accelerate bone regeneration in scaffolded and nonscaffolded calvarial defects. The cranium of experimental rats (n = 8) in which the 5-mm bilateral defects either contained a collagen scaffold or were left empty received oscillatory accelerations (45 Hz, 0.4 g) for 20 minutes per day for 3 weeks. Compared with scaffolded defects in the untreated control group (n = 6), defects with a scaffold and subject to oscillatory accelerations had a 265% greater fractional bone defect area 4 weeks after the surgery. After 8 weeks of healing (1-week recovery, 3 weeks of stimulation, 4 weeks without stimulation), the area (181%), volume (137%), and thickness (53%) of the regenerating tissue in the scaffolded defect were greater in experimental than in control animals. In unscaffolded defects, mechanical stimulation induced an 84% greater bone volume and a 33% greater thickness in the defect. These data provide preliminary evidence that extremely low-level, high-frequency accelerations can enhance osseous regenerative processes, particularly in the presence of a supporting scaffold.

Assessment of the potential of growth factors for localized alveolar ridge augmentation: a systematic review

OBJECTIVE

To systematically assess the literature regarding the clinical, histological, and radiographic outcome of bone morphogenetic proteins (BMP-2, BMP-7), growth/differentiation factor-5 (GDF-5), platelet-derived growth factor (PDGF), and parathyroid hormone (PTH) for localized alveolar ridge augmentation.

MATERIAL AND METHODS

Five separate Medline searches were performed in duplicate for human and animal studies, respectively. The primary outcome of the included studies was bone regeneration of localized alveolar ridge defects or craniofacial defects.

RESULTS

In six human studies, BMP-2 affected local bone augmentation with increasing volume for higher doses. A majority (43 of 45) of animal studies using BMP-2 showed a positive effect in favour of the growth factor (GF). In six of eight studies, a positive effect was associated with the use of BMP-7. Only one animal study was included for GDF-5 revealing statistically significantly higher bone volume. Regarding PDGF, statistically significantly higher bone volume was observed in five of 10 included studies. Four animal studies using PTH revealed statistically significantly more bone regeneration compared with controls.

CONCLUSIONS

Differing levels and quantity of evidence were noted to be available for the GFs evaluated, revealing that BMP-2, BMP-7, GDF-5, PDGF, and PTH may stimulate local bone augmentation to various degrees. Human data for the potential of rhBMP-2 are supportive.