Nanostructured Zn-Substituted Monetite Based Material Induces Higher Bone Regeneration Than Anorganic Bovine Bone and β-Tricalcium Phosphate in Vertical Augmentation Model in Rabbit Calvaria

The capacity of a nanostructured multicomponent material composed of Zn-substituted monetite, amorphous calcium phosphate, hydroxyapatite and silica gel (MSi) to promote vertical bone augmentation was compared with anorganic bovine bone (ABB) and synthetic β-tricalcium phosphate (β-TCP). The relation between biological behavior and physicochemical properties of the materials was also studied. The in vivo study was conducted in a vertical bone augmentation model in rabbit calvaria for 10 weeks. Significant differences in the biological behavior of the materials were observed. MSi showed significantly higher bone regeneration (39%) than ABB and β-TCP (24%). The filled cylinder volume was similar in MSi (92%) and ABB (91%) and significantly lower in β-TCP (81%) implants. In addition, β-TCP showed the highest amount of non-osteointegrated particles (17%). MSi was superior to the control materials because it maintains the volume of the defect almost full, with the highest bone formation, the lowest number of remaining particles, which are almost fully osteointegrated and having the lowest amount of connective tissue. Besides, the bone formed was mature, with broad trabeculae, high vascularization and osteogenic activity. MSi resorbs gradually over time with an evident increment of the porosity and simultaneous colonization for vascularized new bone. In addition, the osteoinductive behavior of MSi material was evidenced.

FEATURES OF PREOPERATIVE MANAGEMENT AND METHODS OF EXAMINATION OF PATIENTS OF GROUPS UNDER RESEARCH

Despite the active ability to repair, it is frequently noticed that the independent potentialof bone tissue is insufficient, that is a serious problem in reconstructive maxillofacialsurgery, orthopedics and traumatology. In recent years, there has been an activesearch for implant material that would match the autologous bone in its properties andcharacteristics. Tissue engineering technologies allow to create tissue equivalents tobone tissue using autogenous stromal cells deposited on biocompatible or biologicalmaterial of tissue engineering design. The article presents the features of preoperativemanagement, description of the used examination methods and bone augmentationmaterials in patients of the groups under study.Objective – to use a set of adequate methods of examination and optimal preoperativemanagement of patients of the group under study during sinus lifting, post-extractionsocket preservation, osteosynthesis for mandibular fractures and impacted wisdom teethextraction, which were accompanied by the use of bone augmentation materials based onmultipotent mesenchymal stromal cells.Material and methods. 280 people aged 18 to 55 with partial or complete adentiaand atrophy of the alveolar process of the jaws, with chronic periodontium infectionand chronic generalized periodontitis, with fractures and impacted third molars wereexamined in the Department of Surgical Dentistry and Maxillofacial Surgery of theChernivtsi Regional Clinical Hospital. All patients were planned to make orthopedicstructures based on dental implants.Results. The use of computed tomography in preoperative examination of patients in thestudied group allows not only visually to examine the object, but also to perform directdensitometric analysis with measurement of attenuation coefficients in Hounsfield units,that is a significant advantage over X-ray examination.Conclusions. The use of bone augmentation materials based on multipotent mesenchymalstromal cells of adipose tissue during dental operations improves the regenerativeproperties of bone tissue and helps to reduce the duration of inpatient treatment.

Implant restoration of hypodontia resulting from ectodermal dysplasia: a case report

Background Ectodermal dysplasia is a congenital genetic disorder with a prevalence of 1:10,000 to 1:100,000. The clinical features of ectodermal dysplasia include sparse hair, missing teeth, and abnormal development of the skin, sweat glands, and other tissues and organs. Since 1985, dentists have used implants to correct tooth defects in patients with ectodermal dysplasia with reasonable success rates. However, there is still no widely accepted treatment for the oral defects caused by this disease. Case summary: This report describes a 19-year-old female patient with congenital ectodermal dysplasia, congenital absence of most of her teeth, and mandibular and maxillary dysplasia. The patient and her family were concerned about the patient’s growth and development, so she came to our hospital to restore her missing teeth. During several months of treatment, the patient underwent bone augmentation surgery for the maxilla and mandible, implant placement, a root repositioning flap, and free gingival grafting, which was completed in five stages. The patient completed the permanent implant restoration, and the desired results were achieved. Conclusion The patient’s mouth was restored through the use of bone augmentation and soft tissue grafting techniques, enabling appropriate function and appearance.

Gene-Activated Matrix with Self-Assembly Anionic Nano-Device Containing Plasmid DNAs for Rat Cranial Bone Augmentation

We have developed nanoballs, a biocompatible self-assembly nano-vector based on electrostatic interactions that arrange anionic macromolecules to polymeric nanomaterials to create nucleic acid carriers. Nanoballs exhibit low cytotoxicity and high transfection efficiently in vivo. This study investigated whether a gene-activated matrix (GAM) composed of nanoballs containing plasmid (p) DNAs encoding bone morphogenetic protein 4 (pBMP4) could promote bone augmentation with a small amount of DNA compared to that composed of naked pDNAs. We prepared nanoballs (BMP4-nanoballs) constructed with pBMP4 and dendrigraft poly-L-lysine (DGL, a cationic polymer) coated by γ-polyglutamic acid (γ-PGA; an anionic polymer), and determined their biological functions in vitro and in vivo. Next, GAMs were manufactured by mixing nanoballs with 2% atelocollagen and β-tricalcium phosphate (β-TCP) granules and lyophilizing them for bone augmentation. The GAMs were then transplanted to rat cranial bone surfaces under the periosteum. From the initial stage, infiltrated macrophages and mesenchymal progenitor cells took up the nanoballs, and their anti-inflammatory and osteoblastic differentiations were promoted over time. Subsequently, bone augmentation was clearly recognized for up to 8 weeks in transplanted GAMs containing BMP4-nanoballs. Notably, only 1 μg of BMP4-nanoballs induced a sufficient volume of new bone, while 1000 μg of naked pDNAs were required to induce the same level of bone augmentation. These data suggest that applying this anionic vector to the appropriate matrices can facilitate GAM-based bone engineering.

EFFECTS OF BONE AUGMENTATION MATERIALS ON PECULIARITIES OF POSTOPERATIVE PERIOD IN PATIENTS AFTER IMPACTED THIRD MOLAR EXTRACTION AND THEIR CLINICAL EFFICIENCY

The article presents a comparative analysis of the clinical effectiveness of bone augmentation materials, in particular, compositions including multipotent mesenchymal stromal cells of adipose tissue and platelet-enriched plasma, used to fill bone defects during the operation of third molars extraction. The criteria for the effectiveness of treatment at the stage of the early postoperative period in the participants included the assessment of the pain intensity, collateral oedema and hyperaemia of the oral mucosa after the surgery. The aim of the study is to determine the clinical efficiency of osteoplastic materials and to determine the feasibility of using tissue equivalents of bone tissue based on multipotent mesenchymal stromal cells of adipose tissue for healing of bone defects in patients with impacted third molars. Methods and participants. The study was conducted on the basis of the Department of Surgical Dentistry and Maxillofacial Surgery of Bukovynian State Medical University, Chernivtsi, Ukraine. Extraction of impacted third molars surgery was performed on 72 patients. After the tooth extraction, 31.94% of them underwent bone augmentation by osteoplastic material “Colapan–L” (group A); 41.67% of patients had bone augmentation with a combination of multipotent mesenchymal stromal cells of adipose tissue+”Colapan–L”+platelet-rich plasma (group B), and in the rest, 26.39% of patients, wound healing occurred under a blood clot (group C). Postoperative pain syndrome was assessed using the Numerical Rating Scale (NRS) based on patients' subjective feeling of pain. Visual assessment of the severity of collateral oedema and hyperaemia of the oral mucosa after surgery was also performed. A scoring system was used to determine the severity of collateral oedema. To assess the state of the postoperative period in patients of all study groups, a protocol was completed daily during the hospital stay period that reflected the most important data of an objective and subjective nature. During the procedure of morning dressings, we analyzed patients' complaints and evaluated general and local status: presence of appetite, quality of sleep, wound pain, postoperative oedema, hematoma, and hyperaemia of the oral mucosa, presence of secretions from the wound, body temperature, and type of wound healing. The study has demonstrated that at the final stage of postoperative follow-up the 89.31% of patients who received a combination of “Colapan–L” with multipotent mesenchymal stromal cells of adipose tissue and platelet-rich plasma reported no pain that is 1.2 times p1<0.05 and 1.3 times p2<0.05 higher than in the patients of groups A and B. Collateral oedema was absent in 98.47% of the group B patients that exceeded 1.2 times p1<0.05 the number of such individuals in group A, where the bone defect was augmented with the osteoplastic material “Colapan–L”, and in 1.4 times higher, p1<0.01, p1>0.05 that the indicators of group B, where the healing of the bone defect developed without osteoplastic materials. The absence of hyperaemia of the oral mucosa was found in 92.37% of the patients in groups B, which was 1.3 and 1.4 times higher than the values obtained in groups A and B, p1<0.05, p2<0.01.