Histomorphometric study of rabbit's maxillary sinus augmentation with various graft materials

Tooth Graft: An Umbrella Overview

This umbrella review aims to evaluate systematic/meta-analysis studies containing clinical evidence on tooth grafts as bone substitutes in the oral and maxillofacial regions. Using language restrictions and Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, an electronic database search of PubMed, MEDLINE, Embase, Cochrane library, and Google Scholar was conducted, featuring published studies up until August 2022. All systematic/meta-analysis review articles relating to tooth graft materials were matched against the inclusion criteria. Two qualified researchers independently assessed the studies' inclusion or exclusion criteria and risk of bias, and a third investigator assisted in resolving ambiguities. A total of 81 systematic/meta-analysis studies, comprising 21 animal-controlled trials, 23 randomized controlled human trials, 23 prospective studies, and 14 retrospective studies, were selected for this study. A small risk of bias was observed in systematic studies/meta-analyses. In addition, the clinical evidence from the analysis of these studies revealed a low incidence of side effects. According to the current review, two systematic reviews indicated that autogenous bone grafting of prepared teeth might be as effective as other bone grafting materials. Four studies also mentioned autologous grafts as potential alternatives to autologous grafts, autogenous demineralized dentin (ADDM), engineered grafts, root blocks, and dental matrix. On the other hand, three systematic studies stated that more long-term research is needed to confirm their findings. Finally, given the importance of standardization and homogeneity of studies for clinical cases, it is advised to be used cautiously due to the risks of transplant rejection.

Early tissue and healing responses after maxillary sinus augmentation using horizontal platelet rich fibrin bone blocks

BACKGROUND

The effects of horizontal platelet-rich fibrin (H-PRF) bone block on the healing and immune response during sinus augmentation have not been fully investigated histologically at early time points.

METHODS

Eighteenth male New Zealand white rabbits underwent bilateral sinus augmentation and were divided into two groups: deproteinized bovine bone mineral (DBBM) alone and H-PRF + DBBM (H-PRF bone block) group. Maxilla samples were collected at 3, 7 and 14 days post sinus augmentation procedures and analyzed using histological staining for the number of inflammatory cells, new blood vessels and evidence for early osteoclast bone turnover/remodeling. Furthermore, the effects of H-PRF bone blocks on the migration of osteoblasts and THP-1 macrophages were evaluated using a Transwell assay in vitro.

RESULTS

A higher number of immune cells were found in the H-PRF bone block group at 3 and 7 days post-surgery when compared to the DBBM alone group,most notably in the regions close to the mucosal lining and bone plates. Furthermore, a significantly greater number of new blood vessel formations and early signs of osteoclast development were found in the H-PRF bone block group at 14 days. The in vitro transwell assay further confirmed that culture medium from H-PRF bone block markedly promote the migration of osteoblasts and THP-1 macrophages.

CONCLUSIONS

The findings from this study have shown that H-PRF bone block is capable of increasing early immune cell infiltration leading to the acceleration of neovascularization and speeding the process of bone metabolism in vivo following maxillary sinus grafting with DBBM.

Impact of Different Preparations of Tooth Graft vs Xenogeneic Bone Graft on Bone Healing: An Experimental Study

AIM

This study aims to compare the effect of demineralized xenogeneic tooth graft in its two forms, particulate and block, with bovine xenograft in the healing of a rabbit tibial bone defect model.

MATERIALS AND METHODS

Two monocortical bony defects were made in the right tibias of 36 rabbits, and were divided into four groups. Group I defects were left empty, while group II, III, and IV were filled with bovine xenograft, demineralized particulate tooth graft, and demineralized perforated block tooth graft, respectively for evaluation of the bone healing process. Three rabbits from each group were euthanized at 2, 4, and 6 weeks after surgery. The bone specimens were processed and stained with hematoxylin and eosin (H&E) and osteopontin (OPN) immunohistochemical staining. The results were subjected to image analysis and quantitative evaluation.

RESULTS

Demineralized particulate tooth graft showed the best bone healing capacity compared to all other groups at all time points tested, as it showed a large amount of the formed bone, rapid closure of the defect with a significant increase in OPN expression, and the least amount of the residual grafted particles.

CONCLUSION

In comparison to bovine xenograft and demineralized dentin block graft, the demineralized particulate tooth grafting material is a promising bone grafting substitute as it proved to be osteoconductive, biocompatible, and bioresorbable.

CLINICAL SIGNIFICANCE

Demineralized tooth grafting material can aid in the regeneration of large bone defects, leading to improvement in the filling of the bone defects which can help in oral and maxillofacial reconstruction.

Osteogenic differentiation and inflammatory response of recombinant human bone morphogenetic protein-2 in human maxillary sinus membrane-derived cells

The aim of the present study was to investigate the osteogenic potential of human maxillary sinus membrane (hMSM)-derived cells, and the role of recombinant human bone morphogenetic protein-2 (rhBMP-2) in the inflammatory response of hMSM-derived cells and gingival fibroblasts following sinus floor elevation procedure (SFE). hMSM-derived cells from the samples were isolated, subcultured, and analyzed using immunohistochemical staining and flow cytometry. The hMSM-derived cells obtained from passage 6 were used for Alizarin Red staining and quantitative reverse transcription-quantitative PCR to observe its osteogenic activity and inflammatory reaction upon supplementation with rhBMP-2. The hMSM-derived cells were shown to be heterogeneous, as indicated by their positive expression of human mesenchymal stem cell markers (STRO-1, high mobility group AT-hook 2, CD44, CD105 and OCT-3/4), fibroblast cell marker (fibroblast-specific protein 1) and epithelial cell marker (epithelial cell adhesion molecule). Calcium nodules were found to be more notably evident in the rhBMP-2 group, following osteogenic differentiation. The gene expression of osteogenic markers was significantly upregulated in the cells supplemented with rhBMP-2. Supplementation with rhBMP-2 also enhanced the expression of inflammatory markers in hMSM-derived cells and gingival fibroblasts; however, NF-κB and TNF-α expression was not significantly increased compared with the control in the hMSM-derived cells. hMSM contains mesenchymal stem cells (MSCs) capable of differentiating into osteogenic cells. The supplementation of rhBMP-2 enhanced osteogenic differentiation and induced an inflammatory response which was greater in gingival fibroblasts compared with hMSM-derived cells. In summary, the hMSM is a potential contributor to the osteogenic process following SFE, and the use of rhBMP-2 may increase the inflammatory response accordingly. The gingival tissue may be responsible for the increased inflammatory response by rhBMP-2 and postoperative complications.

Commercially available bone graft substitutes: the impact of origin and processing on graft functionality

Development of effective and cost-efficient bone tissue engineering grafts has been the key area of research for regenerative medicine, yet an ideal grafting material has remained elusive due in large part to the highly dynamic nature of bone. A wide array of materials, both natural and synthetic, have been implemented as potential candidates for commercially available products, yet the gold standard for grafting material still remains autogenous bone. We review currently commercially available bone graft materials and relevant graft characteristics that impact the effectiveness of tissue repair, emphasizing the advantages and disadvantages of materials based on composition and origin. Examined materials were selected through a web-based search for readily accessible and clinically applicable graft materials. Grafts were then categorized according to material source to examine advantages and disadvantages associated with allogenic, xenogeneic, synthetic materials. Lastly, the application of bioactive molecules onto these basal grafts is explored to illustrate the enhancement and regulative capacity of these additives on traditional osteobiologic materials.

The Use of Tooth Derived Bone Graft Materials in Sinus Augmentation Procedures: a Systematic Review

OBJECTIVES

The goal of this systematic review was to assess the current literature about sinus augmentation procedure using different types of tooth derived bone graft materials, thorough analysing the outcomes of sinus grafting with tooth grafts compared to sinus grafting with xenografts, allografts and alloplasts by radiography and histomorphometry.

MATERIAL AND METHODS

An electronic search in the MEDLINE (NCBI PubMed and PubMed Central) database was conducted to identify articles concerning application of tooth bone grafts in sinus augmentation. The search was restricted to English language articles published in the last 10 years (December 2009 to March 2019).

RESULTS

In total, 21 articles were found, out of which 7 met the inclusion criteria and were included in the final synthesis. According to the type of diagnostic tool, data about graft material outcome in sinus was extracted, and included the residual alveolar height, augmented graft height, resorption height as seen in panoramic radiography and histomorphometric analysis of new bone formation and residual graft material.

CONCLUSIONS

Within the limitations of our review, we suggest that tooth derived graft materials are as successful as xenografts, allografts and alloplasts in sinus augmentation procedures according to the radiographic and histomorphometric showings. Additional wider research should be conducted in order to determine whether tooth derived graft materials are superior to the currently used materials.