Effectiveness of xenogeneic and synthetic bone-block substitute materials with/without recombinant human bone morphogenetic protein-2: A preclinical study using a rabbit calvarium model

Vertical bone augmentation using collagenated or non-collagenated bone substitute materials with or without recombinant human bone morphogenetic protein-2 in a rabbit calvarial model

PURPOSE

The aim of this study was to determine 1) the bone-regenerative effect of porcine bone block materials with or without collagen matrix incorporation, 2) the effect of a collagen barrier, and 3) the effect of adding recombinant human bone morphogenetic protein-2 (rhBMP-2) to the experimental groups.

METHODS

Four treatment modalities were applied to rabbit calvaria: 1) deproteinized bovine bone mineral blocks (DBBM), 2) porcine bone blocks with collagen matrix incorporation (PBC), 3) porcine bone blocks alone without collagen matrix incorporation (PB), and 4) PBC blocks covered by a collagen membrane (PBC+M). The experiments were repeated with the addition of rhBMP-2. The animals were sacrificed after either 2 or 12 weeks of healing. Micro-computed tomography (micro-CT), histologic, and histomorphometric analyses were performed.

RESULTS

Micro-CT indicated adequate volume stability in all block materials. Histologically, the addition of rhBMP-2 increased the amount of newly formed bone (NB) in all the blocks. At 2 weeks, minimal differences were noted among the NB of groups with or without rhBMP-2. At 12 weeks, the PBC+M group with rhBMP-2 presented the greatest NB (P<0.05 vs. the DBBM group with rhBMP-2), and the PBC and PB groups had greater NB than the DBBM group (P>0.05 without rhBMP-2, P<0.05 with rhBMP-2).

CONCLUSIONS

The addition of rhBMP-2 enhanced NB formation in vertical augmentation using bone blocks, and a collagen barrier may augment the effect of rhBMP-2.

Research Hotspots and Trends of Bone Xenograft in Clinical Procedures: A Bibliometric and Visual Analysis of the Past Decade

BACKGROUND

Bone defect therapy is a common clinical challenge for orthopedic and clinical physicians worldwide, and the therapeutic effect affects the physiological function and healthy life quality of millions of patients. Compared with traditional autogenous bone transplants, bone xenografts are attracting attention due to their advantages of unlimited availability and avoidance of secondary damage. However, there is currently a lack of bibliometric analysis on bone xenograft. This study aimed to use bibliometric methods to analyze the literature on bone xenograft from 2013 to 2023, to explore the current status, hotspots, and future trends of research in this field, and to promote its development and progress.

METHODS

Using the Web of Science Core Collection database, we retrieved and collected publication data related to xenogeneic bone grafting materials worldwide from January 2013 to March 2023. Origin (2021), CiteSpace (6.2.R2 standard), and an online bibliometric platform were used for bibliometric analysis and data visualization.

RESULTS

A total of 3395 documents were retrieved, and 686 eligible papers were selected. The country and institutions with the highest number of publications and centrality were the United States (125 papers, centrality = 0.44) and the University of Zurich (29 papers, centrality = 0.28), respectively. The most cited author was Araujo MG (163 times), and the author with the most significant centrality was Froum SJ (centrality = 0.09). The main keyword clusters were "tissue engineering", "sinus floor elevation", "dental implants", "tooth extraction", and "bone substitutes". The most significant bursting keywords in the last three years were "platelet rich fibrin".

CONCLUSIONS

Research on bone xenograft is steadily growing and will continue to rise. Currently, research hotspots and directions are mainly focused on dental implants related to bone-augmentation techniques and bone tissue engineering. In the future, research hotspots and directions may focus on decellularization technology and investigations involving platelet-rich fibrin.

Challenges and tissue engineering strategies of periodontal guided tissue regeneration

Periodontitis is a chronic infectious oral disease with a high prevalence rate in the world, and is a major cause of tooth loss. Nowadays, people have realized that the local microenvironment that includes proteins, cytokines, and extracellular matrix has a key influence on the functions of host immune cells and periodontal ligament stem cells during a chronic infectious disease such as periodontitis. The above pathological process of periodontitis will lead to a defect of periodontal tissues. Through the application of biomaterials, biological agents, and stem cells therapy, guided tissue regeneration (GTR) makes it possible to reconstruct healthy periodontal ligament tissue after local inflammation control. To date, substantial advances have been made in periodontal guided tissue regeneration. However, the process of periodontal remodeling experiences complex microenvironment changes, and currently periodontium regeneration still remains to be a challenging feat. In this review, we summarized the main challenges in each stage of periodontal regeneration, and try to put forward appropriate biomaterial treatment mechanisms or potential tissue engineering strategies that provide a theoretical basis for periodontal tissue engineering regeneration research.

The effect of 3-D printed polylactic acid scaffold with and without hyaluronic acid on bone regeneration

BACKGROUND

Three- dimensional (3D) technology has been suggested to overcome these limitations in guided bone regeneration (GBR) procedures because 3D-printed scaffolds can be easily molded to patient-specific bone defect site. This study aimed to investigate the effect of 3-D printed polylactic acid (PLA) scaffolds with or without hyaluronic acid (HA) in a rabbit calvaria model.

METHODS

A calvaria defect with a diameter of 15 mm was created in 30 New Zealand white rabbits. The rabbits were randomly allocated into 3 groups including no graft group (control, n = 10) , 3D printed PLA graft group (3D-PLA, n = 10) , and 3D printed PLA with hyaluronic acid graft group (3D-PLA/HA, n = 10) . Five animals in each group were sacrificed at 4 and 12 weeks after surgery. Microcomputed tomography and histologic and histomorphometric analyses were performed.

RESULTS

Over the whole examination period, no significant adverse reactions were observed. There were no statistically significant differences in bone volume (BV) /tissue volume (TV) among the three groups at 4 weeks. However, the highest BV/TV was observed in the 3D-PLA/HA group at 12 weeks. The new bone area for control, 3D-PLA, and 3D-PLA/HA showed no statistical differences at 4 weeks. However, the value was significantly higher in the 3D-PLA and 3D-PLA/HA groups compared to the control group at 12 weeks.

CONCLUSION

The 3D printed PLA scaffolds was biocompatible and integrated well with bone defect margin. They were also provided the proper space for new bone formation. Therefore, 3D printed PLA/HA might be a potential tool to enhance bone augmentation. This article is protected by copyright. All rights reserved.