Efficiency and Safety of Dental Implantation in the Area of Hyperdense Jaw Lesions: A Narrative Review

Background. Mineralized lesions of the jaws are often found incidentally on radiographs and computed tomography. Most of them are benign, and only a few rare cases are associated with malignant transformation. However, there is little clinical data on successful rehabilitation with implants in patients with mineralized lesions. This narrative review aimed to study the efficiency and safety of dental implantation in the area of hyperdense lesions. Materials and Methods. A PubMed, Google Scholar, and Science Direct database search was carried out with keywords and manually. Results. The literature exploration identified 323 articles; only 19 of them matched the search criteria and reported cases about dental implantation in the lesion area. It has been shown that in 84.2% of described cases, dental implantation was successful: in the osteoid osteoma, odontoma, cementoblastoma, idiopathic osteosclerosis, and condensing osteitis areas dental implantation was performed without any complications. The possibility of lesion recurrence and implant failure limited the use of dental implants in the area of osteoblastoma and cemento-osseous dysplasia. Although most cases of dental implantation in hyperdense jaw lesions were successful and were not accompanied by complications, further research is needed

Influence of the Degree of Deacetylation of Chitosan and BMP-2 Concentration on Biocompatibility and Osteogenic Properties of BMP-2/PLA Granule-Loaded Chitosan/β-Glycerophosphate Hydrogels

Compositions based on chitosan/β-glycerophosphate hydrogels with highly porous polylactide granules can be used to obtain moldable bone graft materials that have osteoinductive and osteoconductive properties. To eliminate the influence of such characteristics as chain length, degree of purification, and molecular weight on a designed material, the one-stock chitosan sample was reacetylated to degrees of deacetylation (DD%) of 19.5, 39, 49, 55, and 56. A study of the chitosan/β-glycerophosphate hydrogel with chitosan of a reduced DD% showed that a low degree of deacetylation increased the MSCs (multipotent stromal cells) viability rate in vitro and reduced the leukocyte infiltration in subcutaneous implantation to Wistar rats in vivo. The addition of 12 wt% polylactide granules resulted in optimal composite mechanical and moldable properties, and increased the modulus of elasticity of the hydrogel-based material by approximately 100 times. Excessive filling of the material with PLA (polylactide) granules (more than 20%) led to material destruction at a ~10% strain. Osteoinductive and osteoconductive properties of the chitosan hydrogel-based material with reacetylated chitosan (39 DD%) and highly porous polylactide granules impregnated with BMP-2 (bone morphogenetic protein-2) have been demonstrated in models of orthotopic and ectopic bone formation. When implanted into a critical-size calvarial defect in rats, the optimal concentration of BMP-2 was 10 μg/mL: bone tissue areas filled the entire material’s thickness. Implantation of the material with 50 μg/mL BMP-2 was accompanied with excessive growth of bone tissue and material displacement beyond the defect. Significant osteoinductive and osteoconductive properties of the material with 10 μg/mL of BMP-2 were also shown in subcutaneous implantation

Osteoinductive Moldable and Curable Bone Substitutes Based on Collagen, BMP-2 and Highly Porous Polylactide Granules, or a Mix of HAP/β-TCP

In dentistry, maxillofacial surgery, traumatology, and orthopedics, there is a need to use osteoplastic materials that have not only osteoinductive and osteoconductive properties but are also convenient for use. In the study, compositions based on collagen hydrogel were developed. Polylactide granules (PLA) or a traditional bone graft, a mixture of hydroxyapatite and β-tricalcium phosphate (HAP/β-TCP), were used for gel filling to improve mechanical osteoconductive properties of compositions. The mechanical tests showed that collagen hydrogels filled with 12 wt% highly porous PLA granules (elastic modulus 373 ± 55 kPa) or 35 wt% HAP/β-TCP granules (elastic modulus 451 ± 32 kPa) had optimal manipulative properties. All composite components were cytocompatible. The cell’s viability was above 90%, and the components’ structure facilitated the cell’s surface adhesion. The bone morphogenetic protein-2 (BMP-2) provided osteoinductive composition properties. It was impregnated directly into the collagen hydrogel with the addition of fibronectin or inside porous PLA granules. The implantation of a collagen hydrogel with BMP-2 and PLA granules into a critical-size calvarial defect in rats led to the formation of the most significant volume of bone tissue: 61 ± 15%. It was almost 2.5 times more than in the groups where a collagen-fibronectin hydrogel with a mixture of HAP/β-TCP (25 ± 7%) or a fibronectin-free composition with porous PLA granules impregnated with BMP-2 (23 ± 8%) were used. Subcutaneous implantation of the compositions also showed their high biocompatibility and osteogenic potential in the absence of a bone environment. Thus, the collagen-fibronectin hydrogel with BMP-2 and PLA granules has optimal biocompatibility, osteogenic, and manipulative properties

An experimental research in mice on the “soft tissue reaction to 3 different mesh implants: Titanium silk, Parietene Progrip and Prolene”

Purpose: To analyze the soft tissue reaction of ‘Titanium Silk’ mesh implant in comparison with ‘Parietene Progrip’ and ‘Prolene’ mesh implants for the reinforcement and augmentation of soft tissues to improve the results of static correction in Facial Paralysis and other defects of Maxillofacial region. Materials and methods: Under standard laboratory conditions, 89 mice were divided into 4 groups: a control group of 5 mice; first group of 28 mice with Titanium mesh implant, second group of 28 mice with semi-resorbable ‘Parietene Progrip’ implant and third group of 28 mice with ‘Prolene’ implant. Under inhalational anesthesia with ethyl ether at days 7, 14, 30 and 60, seven mice from each experimental group underwent Gross and histological analysis of the mesh structures for the following characteristics: Macrophage Infiltration, Multinucleated Macrophages, Meshwork around the implant fibers, Connective tissue proliferation, Angiogenesis and Fibroblasts. Results: Histological analysis revealed a significantly less pronounced inflammatory response to Titanium mesh implant resulting in the formation of a more delicate connective tissue network around the mesh elements. Conclusion: The experiment clearly demonstrated the cellular and tissue responses to different implantable mesh materials at various times of its integration. It revealed that the titanium mesh is the most bio-inert alloplastic material suitable for reinforcement of soft tissue augmentation and to prioritize it's use in static correction of facial paralysis and other defects of the maxillofacial region. A postoperative timeframe of 30 days is considered appropriate for the adequate formation of connective tissue around the mesh elements. Keywords: Titanium silk, Parietene Progrip, Prolene, Mesh implant, Histological mesh analysis, Static facial nerve repai

Comparative Efficiency of Gene-Activated Matrices Based on Chitosan Hydrogel and PRP Impregnated with <i>BMP2</i> Polyplexes for Bone Regeneration

Gene therapy is one of the most promising approaches in regenerative medicine. Gene-activated matrices provide stable gene expression and the production of osteogenic proteins in situ to stimulate osteogenesis and bone repair. In this study, we developed new gene-activated matrices based on polylactide granules (PLA) impregnated with BMP2 polyplexes and included in chitosan hydrogel or PRP-based fibrin hydrogel. The matrices showed high biocompatibility both in vitro with mesenchymal stem cells and in vivo when implanted intramuscularly in rats. The use of porous PLA granules allowed the inclusion of a high concentration of polyplexes, and the introduction of the granules into hydrogel provided the gradual release of the plasmid constructs. All gene-activated matrices showed transfecting ability and ensured long-term gene expression and the production of target proteins in vitro. At the same time, the achieved concentration of BMP-2 was sufficient to induce osteogenic differentiation of MSCs. When implanted into critical-size calvarial defects in rats, all matrices with BMP2 polyplexes led to new bone formation. The most significant effect on osteoinduction was observed for the PLA/PRP matrices. Thus, the developed gene-activated matrices were shown to be safe and effective osteoplastic materials. PLA granules and PRP-based fibrin hydrogel containing BMP2 polyplexes were shown to be the most promising for future applications in bone regeneration

Osteoinductive Moldable and Curable Bone Substitutes Based on Collagen, BMP-2 and Highly Porous Polylactide Granules, or a Mix of HAP/β-TCP

In dentistry, maxillofacial surgery, traumatology, and orthopedics, there is a need to use osteoplastic materials that have not only osteoinductive and osteoconductive properties but are also convenient for use. In the study, compositions based on collagen hydrogel were developed. Polylactide granules (PLA) or a traditional bone graft, a mixture of hydroxyapatite and β-tricalcium phosphate (HAP/β-TCP), were used for gel filling to improve mechanical osteoconductive properties of compositions. The mechanical tests showed that collagen hydrogels filled with 12 wt% highly porous PLA granules (elastic modulus 373 ± 55 kPa) or 35 wt% HAP/β-TCP granules (elastic modulus 451 ± 32 kPa) had optimal manipulative properties. All composite components were cytocompatible. The cell’s viability was above 90%, and the components’ structure facilitated the cell’s surface adhesion. The bone morphogenetic protein-2 (BMP-2) provided osteoinductive composition properties. It was impregnated directly into the collagen hydrogel with the addition of fibronectin or inside porous PLA granules. The implantation of a collagen hydrogel with BMP-2 and PLA granules into a critical-size calvarial defect in rats led to the formation of the most significant volume of bone tissue: 61 ± 15%. It was almost 2.5 times more than in the groups where a collagen-fibronectin hydrogel with a mixture of HAP/β-TCP (25 ± 7%) or a fibronectin-free composition with porous PLA granules impregnated with BMP-2 (23 ± 8%) were used. Subcutaneous implantation of the compositions also showed their high biocompatibility and osteogenic potential in the absence of a bone environment. Thus, the collagen-fibronectin hydrogel with BMP-2 and PLA granules has optimal biocompatibility, osteogenic, and manipulative properties