Quality Of Regenerated Bone Research Articles

Biphasic Calcium Phosphate in the Extraction Socket Preservation: A Systematic Review

ABSTRACT Introduction: Various studies have suggested use of socket grafting materials after dental extraction for socket preservation. However, there is no single material that has been accepted as standard for preserving the socket. The purpose of this systematic review was to analyze the evidence for the use of biphasic calcium phosphate for socket regeneration. Materials and Methods: The team conducted a systematic literature search in accordance with the protocol registered at PROSPERO. PubMed, OVID, and EMBASE databases were used in the search. The articles were then screened using RAYYAN open-source software for the synthesis of evidence. Results: Of the 240 articles found in the search, two studies could be included in the review. Conclusion: Biphasic calcium phosphate (60% hydroxyapatite, HA and 40% beta-tricalcium phosphate, β-TCP) has a significant effect in the socket preservation and quality of bone regeneration.

The additive effects of bioactive glasses and photobiomodulation on enhancing bone regeneration.

Bioactive glasses (BG) have been generally used in bone defects repair for its good osteoinductivity and osteoconductivity. However, the early angiogenesis of BG in the repair of large-sized bone defects may not be sufficient enough to support new bone formation, resulting in the failure of bone repair. Photobiomodulation (PBM) therapy, which is superior on promoting early angiogenesis, may contribute to the angiogenesis of BG and further enhance the repair of bone defects. Therefore, we applied BG and PBM in combination and preliminarily investigated their additive effects on bone regeneration both in vitro and in vivo. The in vitro results revealed that BG combined with PBM remarkably enhanced human bone marrow mesenchymal stem cells proliferation, osteogenic-related genes expression and mineralization, which was better than applying BG or PBM respectively. For in vivo studies, the histological staining results showed that BG induced new bone formation in the interior of defects and promoted new bone reconstruction at 6 weeks post-operation. The micro-computed tomography results further confirmed that BG combined with PBM accelerated bone formation and maturation, improved the speed and quality of bone regeneration, and promoted bone repair. In conclusion, with the optimum BG and PBM parameters, BG combined with PBM generated additive effects on promoting bone regeneration.

Temporal metabolic profiling of bone healing in a caprine tibia segmental defect model.

Bone tissue engineering is an emerging field of regenerative medicine, with a wide array of biomaterial technologies and therapeutics employed. However, it is difficult to objectively compare these various treatments during various stages of tissue response. Metabolomics is rapidly emerging as a powerful analytical tool to establish broad-spectrum metabolic signatures for a target biological system. Developing an effective biomarker panel for bone repair from small molecule data would provide an objective metric to readily assess the efficacy of novel therapeutics in relation to natural healing mechanisms. In this study we utilized a large segmental bone defect in goats to reflect trauma resulting in substantial volumetric bone loss. Characterization of the native repair capacity was then conducted over a period of 12 months through the combination of standard (radiography, computed tomography, histology, biomechanics) data and ultra-high-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS) metabolic profiling. Standard metrics demonstrated that samples formed soft callus structures that later mineralized. Small molecule profiles showed distinct temporal patterns associated with the bone tissue repair process. Specifically, increased lactate and amino acid levels at early time points indicated an environment conducive to osteoblast differentiation and extracellular matrix formation. Citrate and pyruvate abundances increased at later time points indicating increasing mineral content within the defect region. Taurine, shikimate, and pantothenate distribution profiles appeared to represent a shift toward a more homeostatic remodeling environment with the differentiation and activity of osteoclasts offsetting the earlier deposition phases of bone repair. The generation of a comprehensive metabolic reference portfolio offers a potent mechanism for examining novel biomaterials and can serve as guide for the development of new targeted therapeutics to improve the rate, magnitude, and quality of bone regeneration.

Outcome Analysis of Osseous Ingrowth in an Artificially Created Gap Non-union Using the Novel 3D Biodegradable Polycaprolactone Poly-l-Lactide Polymer Scaffold: Insights from an Experimental Study.

Synthetic biopolymers have been widely used to manage bone effects in recent years. The study aims to analyse the ability to repair artificially created ulnar bone defects with the scaffold made of Polycaprolactone (PCL) and investigate the material's feasibility as a bone graft substitute. We have tested a novel 3D biodegradable Polycaprolactone Poly-l-Lactide polymer scaffold in an experimental animal model. 14 adults New Zealand white rabbits were used to create the ulnar defect model of 10mm in length, and randomly divided into group A (test-12 rabbits), group B (control-3 rabbits). The defect area was implanted with the PCL scaffold in the test group, whereas it was left as such in the control group. The repairing effect was observed by gross, histology, radiology, and the Scanning electron microscopy (SEM) at 4, 8, and 12weeks. Cook's scoring was used to assess the radiological parameters. Histological and radiological results showed better quality of bone regeneration in the defect area at 12week follow-up period. The SEM image at that period showed impregnation of the osteogenic cells in the surface and pores of the scaffold material. It was evident that the scaffold was thoroughly degraded, corresponding with osteogenesis. New bone formation was statistically significant in the test group than in the control group. The Polycaprolactone Poly-l-Lactide polymer scaffold is biodegradable in-vivo at a suitable half-life. It has an excellent porous structure, no tissue toxicity, excellent mechanical strength, high osteogenesis potential, and osteoconductivity. Therefore, it can be used as bone graft material in the gap non-union and as a void filler in bone defects.

The horizon of bone organoid: A perspective on construction and application.

Bone defects repair and regeneration by various causes such as tumor resection, trauma, degeneration, etc. have always been a key issue in the clinics. As one of the few organs that can regenerate after adulthood, bone itself has a strong regenerative ability. In recent decades, bone tissue engineering technology provides various types of functional scaffold materials and seed cells for bone regeneration and repair, which significantly accelerates the speed and quality of bone regeneration, and many clinical problems are gradually solved. However, the bone metabolism mechanism is complicated, the research duration is long and difficult, which significantly restricts the progress of bone regeneration and repair research. Organoids as a new concept, which is built in vitro with the help of tissue engineering technology based on biological theory, can simulate the complex biological functions of organs in vivo. Once proposed, it shows broad application prospects in the research of organ development, drug screening, mechanism study, and so on. As a complex and special organ, bone organoid construction itself is quite challenging. This review will introduce the characteristics of bone microenvironment, the concept of organoids, focus on the research progress of bone organoids, and propose the strategies for bone organoid construction, study direction, and application prospects.

Effect of Photobiomodulation on Relapse in an Experimental Rapid Maxillary Expansion Model in Rat.

Rapid maxillary expansion (RME) is performed on transversely deficient maxilla. As all orthodontic treatments, retention is important in maintaining therapeutic outcomes. Fixed /removable retainers are used post-RME causing hygiene and compliance problems. Given photobiomodulation's positive effects on the quantity and quality of bone regeneration, its effect on post-RME relapse was studied. Thirty Sprague Dawley rats were randomly divided into group R, non-irradiated RME-treated (n=12), group P, irradiated RME-treated (n=12) and group C, non-RME non-irradiated (n=6). A 1.5mm metal ring inserted between maxillary incisors at days 0 and 15 was expanded until 1.5mm space was obtained at day 30. In group P, Ga-Al-As diode laser (810nm, 100mW, 4J/cm2 , 30secs) was applied on days 0, 2, 4, 6, 8, 10, 12 and 14 as predictor variable. The relapse was measured as the space lost between incisors for 30days after appliance removal (primary outcome variable) and compared with t-test. In week 2, space loss in group P was significantly lower (P<0.05) than all other groups. The relapse during weeks 2 and 3 was significantly lower in group P than group R. However, no significant difference in relapse amount was found between groups during first and fourth week. There was a significant difference (P<0.05) between groups in relapse rates (secondary outcome variable) but not in total relapse after 4weeks. Photobiomodulation proved beneficial in resisting relapse in our study, and it is suggested to be continued until the end of expansion.

Regenerated Bone Pattern Around Exposed Implants with Various Designs.

The design and surface features of dental implants substantially affect the healing and remodeling of adjacent bones. This study aimed to investigate the impact of design and surface on bone regeneration using implants of two different pitches, each with three different surface features. Custom-manufactured titanium implants (length, 10 mm; diameter, 3.5 mm) were divided along the major axis into two sections: one with 0.6-mm pitch and the other with 0.4-mm pitch. They were processed by turned, blasting and etching, and anodic oxidation surface treatments and implanted into rabbit tibia. The upper 4 mm of the inserted implants was exposed, and bone regeneration was induced around the exposed area using a titanium chamber (height: 4 mm) containing particulate autogenous and bovine bone. After a 12-week healing period, the quantity and quality of bone regeneration around the implants were evaluated. Thirty specimens-10 specimens each from the turned, blasting and etching, and anodic oxidation surface groups with 0.6- and 0.4-mm pitch sizes- were evaluated by histomophometric analysis. The vertical height and width of regenerated bone around blasting and etching and anodic oxidation surfaces were significantly greater than those around turned implants (P < .05); the vertical heights of regenerated bone around the 0.4-mm-pitch sections of blasting and etching and anodic oxidation surfaces were significantly greater than those around the 0.6-mm-pitch sections (P < .05). Both blasting and etching and anodic oxidation surfaces exhibited significantly greater bone-to-implant contact and bone volume at the implant thread than turned implants (P < .05). However, there was no significant difference between the 0.6- and 0.4-mm-pitch sections. The findings of this study indicate that blasting and etching and anodic oxidation surfaces with a 0.4-mm-pitch design result in greater vertical ingrowth of regenerated bone than those with a 0.6-mm-pitch design.

Reconstruction of oro-facial region; challenges and opportunities

Event Abstract Back to Event Reconstruction of oro-facial region; challenges and opportunities Ashraf A. Ayoub1, Randa Al Fotawi1, K E. Tanner2, Matthew J. Dalby3 and Kurt Naudi1 1 University of Glasgow, Glasgow Dental Hospital & School, United Kingdom 2 University of Glasgow, Biomedical Engineering Division, School of Engineering, United Kingdom 3 University of Glasgow, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, United Kingdom Background: Surgical reconstruction of functional and aesthetic defects, particularly following ablative cancer surgery, is often compromised by limited vascularity and the associated donor site morbidity. A compromised vascular bed is a major obstacle for the successful uptake of a micro-vascular flap. Aim: Investigate a novel approach of using an injectable scaffolding into a pedicled muscle flap for reconstruction of a critical size mandibular defect. Materials and Methods: Under general anesthesia bone marrow was aspirated from both the rabbit’s anterior iliac crest. Cells were cultured and expanded according to a validated standard protocol before application in the surgical defect[1]. A critical size bony defect, 20mm x 15mm, was created in the rabbit’s mandibular body[2]. A fixation plate was applied at the inferior border to maintain the mandibular integrity, while the superior border was maintained. A pedicled masseter muscle flap was rotated and adapted to fill the created surgical defect. An injectable calcium sulfate/hydroxyapatite scaffolding material (Cerament Spine Support) loaded with BMP-7 and mesnechymal stem cells was injected into the muscle flap to induce bone formation. Animals were sacrificed at three months following surgery. The quality of bone regeneration was assessed using Cone Beam Computerised Tomography (CBCT), micro CT and histological assessment. Results: In all the cases sporadic areas of bone regeneration were detected within the muscle flap. In some cases the volume of newly formed bone was more than the volume of bone resected to the create the defect. Bone formation was in close proximity to the injectable scaffold material. Micro CT showed a different trabecular pattern in the regenerated bone to the native bone tissue. Fig 1 Micro CT showing new bone formed in the defect. Histologically, the regenerated tissue consisted of a mixture of mature bone with clear Haversion structure and areas of woven bone. Some areas of fibrous tissue “muscle metaplasia” was detected between the newly generated bone and the surrounding muscle fibres. New bone formation was either from the defect edges or Fig 2 Undecalcified section stained with Goldner’s trichrome, showing resorption of the graft material and new bone formation. Conclusions: The muscle flap acted as a bioreactor for bone induction under the influence of calcium sulfate/hydroxyapatite, stem cells and BMP-7. Three months is insufficient for complete restoration of the bony defect. The new bone formation concentrated around the areas of the injected cells and material. Randa Alfotawi was funded by King Saud University, Ministry of Higher Education; Bone Support AB (Lund, Sweden) is thanked for provision of the Cerament™ bone cements

The effect of platelet-rich fibrin on bone regeneration and angiogenesis in rabbit cranial defects

This study evaluated the effect of platelet-rich fibrin (PRF) on the osteogenesis and angiogenesis of rabbit calvarial defects. The calvarium of nine rabbits was exposed. In each rabbit, two circular bone defects, one on each side of the midline, were prepared using a reamer drill. While the experimental site received PRF, the control sites were left filled with blood. The animals were sacrificed after a period of 1 week (n=3), 2 weeks (n=3), and 4 weeks (n=3). The following histomorphometric data were recorded: 1) the area of the newly formed tissue relative to total bone defect (NT) and the area of newly formed osteoid relative to newly formed tissue (NB), 2) the longest and shortest vertical height of the newly formed tissue relative to the vertical height of normal tissue (LH, SH), 3) newly formed osteoid on the defect margin using region of interest (NBR), and 4) bony pontic formation from the margin was used to evaluate bone growth (OS). The expression of vascular endothelial growth factor (VEGF) was evaluated by immunohistochemical staining. The differences between groups were not significant at any experimental time point. However, a significant linear increase of NB and NBR including OS value according to time was observed in the PRF group. In addition, the intensity and percentage range of VEGF expression showed a significant linear decrease trend with the time in the PRF group. The results of this study suggest that PRF may enhance the quality of bone regeneration.

Socket Preservation: Allograft vs. Alloplast

Background: The volume shrinkage of the alveolar ridge might be minimized by the ridge preservation stagesand applied biomaterials, after tooth extraction. Objectives: The aim of this study is to compare alloplastic with allograft in terms of preservation and bone regeneration of the alveolar ridge after tooth extraction. Materials and Methods: This study clinically assessed this issue via the Split Mouth method which assessed 10 dental sockets filled with alloplasts and 9 others with allografts postextraction. The effectiveness of each material was clinically and histologically processed. The alveolar ridge width was measured by a gauge, before filling the socket and 2 months postextraction when inserting the dental implant. The histological process of bone samples were observed under light microscope at the time of fixture insertion to evaluate live and dead bone, trabecular, amorphous and non- osteoblastic. The changes in two groups in terms of the quantity underwent T-Test examination and the quality of bone regeneration was assessed using MANN-U-WHITNEY test. IRB and ethical approval was granted for our study. Results: Minimal reduction of alveolar ridge widths were observed in both groups (reduction of alveolar ridge in the allograft group: 0.61 mm ± 1.06 and in the alloplast group: 0.85 mm ± 0.88) but the difference was not significant statistically (P=0.6); no significant differences were noted in vital (P=0.9), nonvital (P<0.8), trabecular (P<0.7) or amorphous (P<0.4) bone. Conclusion: Both materials were equal in terms of the quantity and the quality of osteoblasts and both were the same in terms of live and dead bone. No major differences in the regenerated bone could be found between these two groups.

Dentate Transport Discs Can Be Used to Reconstruct Large Segmental Mandibular Defects

This study tested the use of a dentate transport segment for the reconstruction of a large U-shaped defect in the anterior segment of the canine mandible using a novel curved reconstruction plate. The quality and quantity of bone regenerate formed by dentate versus edentulous transport segments were compared. In 5 adult foxhound dogs, a defect of 70 to 75mm was created in the canine mandible by excising the mandible anterior to the right and left fourth premolars. Reconstruction was performed by trifocal distraction osteogenesis using a bone transport reconstruction plate (BTRP-02), with 2 transport units being activated simultaneously, one on either side of the defect, 1 dentate and 1 edentulous. Bilateral distraction proceeded at a rate of 1mm/day until the segments docked against each other in the midline. After 39 to 44 days of consolidation, the animals were euthanized. The quantity and quality of bone regeneration on the 2 sides were compared using micro-computed tomography. The defect reconstruction was successful. The amount and quality of bone formed by the transport segments were similar on the 2 sides. There were no major differences in the bone volume fraction and density of the regenerate bone formed by the 2 transport segments. The bone volume fraction and density of the regenerate bone were considerably lower than those of the host bone in the distal segments, likely owing to the short consolidation period. Bone transport remains a viable option in reconstructing anterior segmental defects in the mandible. The use of dentate or edentulous transport segments for reconstruction provides options for thesurgeon in often highly compromised patients requiring these surgeries.

Role of collagen membrane in lateral onlay grafting with bovine hydroxyapatite incorporated with collagen matrix in dogs

PurposeThe objective of this study was to elucidate the role of collagen membranes (CMs) when used in conjunction with bovine hydroxyapatite particles incorporated with collagen matrix (BHC) for lateral onlay grafts in dogs.MethodsThe first, second, and third premolars in the right maxilla of mongrel dogs (n=5) were extracted. After 2 months of healing, two BHC blocks (4 mm×4 mm×5 mm) were placed on the buccal ridge, one with and one without the coverage by a CM. The animals were sacrificed after 8 weeks for histometric analysis.ResultsThe collagen network of the membranes remained and served as a barrier. The quantity and quality of bone regeneration were all significantly greater in the membrane group than in the no-membrane group (P<0.05).ConclusionsThe use of barrier membranes in lateral onlay grafts leads to superior new bone formation and bone quality compared with bone graft alone.

Hydroxyapathite gel as a basis for pharmaceutic composites

A method has been proposed for producing hydroxyapatite gel, which can be used in surgery and dentistry as a biocompatible and active material for the development of pharmaceutical compositions with an improved quality of bone regeneration and an enhanced therapeutic effect.

Is platelet-rich plasma the perfect enhancement factor? A current review.: Andrés R. Sánchez, Phillip J. Sheridan, Leo I. Kupp. Int J Oral Maxillofac Implants 2003;18:93-103

Guided bone regeneration is an accepted surgical method employed in implant dentistry to increase the quantity and quality of the host bone in areas of localized alveolar defects. The lack of predictability in osseous regenerative procedures with various grafting materials suggests that improvement in the osteoinductive properties of these materials is highly desirable. Platelet-rich plasma (PRP), a modification of fibrin glue made from autologous blood, is being used to deliver growth factors in high concentration to sites requiring osseous grafting. Growth factors released from the platelets include platelet-derived growth factor, transforming growth factor beta, platelet-derived epidermal growth factor, platelet-derived angiogenesis factor, insulin-like growth factor 1, and platelet factor 4. These factors signal the local mesenchymal and epithelial cells to migrate, divide, and increase collagen and matrix synthesis. PRP has been suggested for use to increase the rate of bone deposition and quality of bone regeneration when augmenting sites prior to or in conjunction with dental implant placement Only 6 human studies using PRP have been found in the dental implant literature and 5 were case series or reports. Thus, there is clearly a lack of scientific evidence to support the use of PRP in combination with bone grafts during augmentation procedures. This novel and potentially promising technique requires well-designed, controlled studies to provide evidence of efficacy.