Influence of General Mineral Condition on Collagen-Guided Alveolar Crest Augmentation

The local regeneration of bone defects is regulated by general hormone, enzyme, ion, and vitamin levels. General diseases and dysregulation of the human mineral system can impact this process, even in alveolar crest. The aim of this study is to investigate a relation between bone density, measured in two-dimensional X-rays, and general mineral condition of patients. The study included 42 patients on whom tooth extractions were performed. Data were divided into two groups: the region where collagen scaffold (BRM) was used and the reference region of intact normal bone (REF). Two-dimensional intraoral radiographs were taken in all cases just after the surgery (00 M) and 12 months later (12 M). Thyrotropin (TSH), parathormone (PTH), Ca2+ in serum, HbA1c, vitamin 25(OH)D3, and spine densitometry were checked. Digital texture analysis in MaZda 4.6 software was done. Texture Index (TI: BRM 1.66 ± 0.34 in 00 M, 1.51 ± 0.41 in 12 M, and REF 1.72 ± 0.28) and Bone Index (BI: BRM 0.73 ± 0.17 in 00 M, 0.65 ± 0.22 41 in 12 M, and REF 0.80 ± 0.14) were calculated to evaluate bone regeneration process after 12 months of healing (TI (p < 0.05) and BI (p < 0.01) are lower in BRM 12 M than in REF). This showed a relation between BI and TSH (R2 = 26%, p < 0.05), as well as a between BI and patient age (R2 = 65%, p < 0.001), and a weak relation between TI and TSH level (R2 = 10%, p < 0.05). This study proved that a collagen scaffold can be successfully used in alveolar crest regeneration, especially in patients with a high normal level of TSH in the middle-aged population.

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Assessment of Acetabulum Deformity During Preoperative Planning for Hip Arthroplasty

Traumatology and Orthopedics of Russia ◽

10.21823/2311-2905-2019-25-3-153-164 ◽

2019 ◽

Vol 25 (3) ◽

pp. 153-164

Author(s):

D. V. Martynenko ◽

V. P. Voloshin ◽

L. A. Sherman ◽

K. V. Shevyrev ◽

S. A. Oshkukov ◽

...

Keyword(s):

Acetabular Component ◽

Hip Joint ◽

Preoperative Planning ◽

Bone Defects ◽

Lateral Side ◽

X Rays ◽

Two Dimensional ◽

Acetabular Coverage ◽

Anatomical Features ◽

Medial Side

Purpose of the study — to improve the two-dimensional planning of total hip joint arthroplasty to ensure precise positioning of the acetabular component in the deformed acetabulum. Materials and methods. Features of roentgenological anatomy of acetabulum and its coverage were studied on 1058 hip joint x-rays in the AP view in accordance with the procedure developed by the authors to define acetabular square — the site of standard positioning of a spherical femoral head in the acetabulum or of a hemispherical acetabular component. The method consisted of identifying the apex of “teardrop” figure; the most lateral points of the pelvic terminal line and roof of the acetabulum; superior part of the acetabular cavity; medial and inferior points of acetabular coverage, and building the sides of acetabular square — medial, inferior, lateral and superior boundary lines. Connection of “teardrop” apex and lateral point of the pelvic terminal line formed the medial side of acetabular square, and a perpendicular to that line drawn through the “teardrop” apex to its inferior side. The lateral side was drawn either through the intersection of the ascending diagonal line — bisector from the top of the “teardrop” figure with the contour of the acetabulum roof, or was a part of the projection of the most lateral point of the acetabular roof on the inferior side of the square. The superior side was a perpendicular connecting the intersection of the ascending diagonal and lateral bounding lines with the medial side of the acetabular square. The area of the deformed acetabular cavity located outside of the acetabular square was assessed as the acetabular defect. Results. Method of defining the acetabular square allowed to identify types of ratios between acetabular cavity and acetabular coverage in transverse (9 types) and longitudinal (7 types) direction. Combination of transverse ratio of acetabular cavity and coverage with longitudinal type allowed to define the options of acetabular deformities in two-dimensional view. The authors identified 25 types of acetabular deformities. Bone defects of acetabular walls were of the major importance among all anatomical features. Cranial defect of acetabulum was observed in 450 cases, medial wall defect — in 38 cases, defect including cranial and medial areas — in 7 cases. Conclusion. The method suggested by the authors to determine acetabular square and acetabular deformity variations allows to screen the anatomical features of the acetabulum during two-dimensional preoperative planning and to make an informed decision on the need to use other planning techniques. The type of acetabular deformity identified during preoperative planning allows to elaborate the indications for replacement of acetabular bone defects and/or resection of acetabular osteophytes.

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In vivo Evaluation of a Collagen Scaffold Preconditioned with Adipose-derived Mesenchymal Stem Cells Used for Bone Regeneration A histological study

Materiale Plastice ◽

10.37358/mp.18.4.5102 ◽

2018 ◽

Vol 55 (4) ◽

pp. 691-695

Author(s):

Tudor Sorin Pop ◽

Anca Maria Pop ◽

Alina Dia Trambitas Miron ◽

Klara Brinzaniuc ◽

Simona Gurzu ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Bone Regeneration ◽

Histological Study ◽

Collagen Scaffold ◽

Bone Defects ◽

Collagen Scaffolds ◽

In Vivo Evaluation ◽

Calvarial Bone ◽

Bone Apposition

The use of collagen scaffolds and stem cells for obtaining a tissue-engineering complex has been an important concept in promoting repair and regeneration of the bone tissue. Such units represent important steps in the development of an ideal scaffold-cell complex that would sustain new bone apposition. The aim of our study was to perform a histologic evaluation of the healing of critical-sized bone defects, using a biologic collagen scaffold with adipose-derived mesenchymal stem cells, in comparison to negative controls created in the adjacent bone. We used 16 Wistar rats and according to the study design 2 calvarial bone defects were created in each animal, one was filled with collagen seeded with adipose-derived stem cells and the other one was considered negative control. During the following month, at weekly intervals, the animals were euthanized and the specimens from bone defects were histologically evaluated. The results showed that these scaffolds were highly biocompatible as only moderate inflammation no rejection reactions were observed. Furthermore, the first signs of osseous healing appeared after two weeks accompanied by angiogenesis. Collagen scaffolds seeded with adipose-derived mesenchymal stem cells can be considered a promising treatment option in bone regeneration of large defects.

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Drug Delivery Systems Based on Titania Nanotubes and Active Agents for Enhanced Osseointegration of Bone Implants

Current Medicinal Chemistry ◽

10.2174/0929867326666190726123229 ◽

2020 ◽

Vol 27 (6) ◽

pp. 854-902 ◽

Cited By ~ 5

Author(s):

Raluca Ion ◽

Madalina Georgiana Necula ◽

Anca Mazare ◽

Valentina Mitran ◽

Patricia Neacsu ◽

...

Keyword(s):

Drug Delivery ◽

Tio2 Nanotubes ◽

Therapeutic Agent ◽

Bone Defects ◽

Delivery Systems ◽

Antimicrobial Compounds ◽

Bone Implant ◽

Bioactive Agents ◽

Localized Drug Delivery ◽

Regeneration Of Bone

TiO2 nanotubes (TNTs) are attractive nanostructures for localized drug delivery. Owing to their excellent biocompatibility and physicochemical properties, numerous functionalizations of TNTs have been attempted for their use as therapeutic agent delivery platforms. In this review, we discuss the current advances in the applications of TNT-based delivery systems with an emphasis on the various functionalizations of TNTs for enhancing osteogenesis at the bone-implant interface and for preventing implant-related infection. Innovation of therapies for enhancing osteogenesis still represents a critical challenge in regeneration of bone defects. The overall concept focuses on the use of osteoconductive materials in combination with the use of osteoinductive or osteopromotive factors. In this context, we highlight the strategies for improving the functionality of TNTs, using five classes of bioactive agents: growth factors (GFs), statins, plant derived molecules, inorganic therapeutic ions/nanoparticles (NPs) and antimicrobial compounds.

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Effect of Systemic Zoledronic Acid Dosing Regimens on Bone Regeneration in Osteoporotic Rats

Applied Sciences ◽

10.3390/app11041906 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1906

Author(s):

Marwa Y. Shaheen ◽

Amani M. Basudan ◽

Abdurahman A. Niazy ◽

Jeroen J. J. P. van den Beucken ◽

John A. Jansen ◽

...

Keyword(s):

Bone Graft ◽

Bone Grafting ◽

Femoral Condyle ◽

Bone Defects ◽

Histological Evaluation ◽

Favorable Effect ◽

Osteoporotic Bone ◽

Bovine Bone ◽

Graft Placement ◽

Regeneration Of Bone

The aim of this study was to evaluate the regeneration of bone defects created in the femoral condyle of osteoporotic rats, following intravenous (IV) zoledronate (ZA) treatment in three settings: pre-bone grafting (ZA-Pre), post-bone grafting (ZA-Post), and pre- plus post-bone grafting (ZA-Pre+Post). Twenty-four female Wistar rats were ovariectomized (OVX). After 12 weeks, bone defects were created in the left femoral condyle. All defects were grafted with a particulate inorganic cancellous bovine bone substitute. ZA (0.04 mg/kg, weekly) was administered to six rats 4 weeks pre-bone graft placement. To another six rats, ZA was given post-bone graft placement creation and continued for 6 weeks. Additional six rats received ZA treatment pre- and post-bone graft placement. Control animals received weekly saline intravenous injections. At 6 weeks post-bone graft placement, samples were retrieved for histological evaluation of the bone area percentage (BA%) and remaining bone graft percentage (RBG%). BA% for ZA-Pre (50.1 ± 3.5%) and ZA-Post (49.2 ± 8.2%) rats was significantly increased compared to that of the controls (35.4 ± 5.4%, p-value 0.031 and 0.043, respectively). In contrast, ZA-Pre+Post rats (40.7 ± 16.0%) showed similar BA% compared to saline controls (p = 0.663). For RBG%, all experimental groups showed similar results ranging from 36.3 to 47.1%. Our data indicate that pre- or post-surgical systemic IV administration of ZA improves the regeneration of bone defects grafted with inorganic cancellous bovine-bone particles in osteoporotic bone conditions. However, no favorable effect on bone repair was seen for continued pre- plus post-surgical ZA treatment.

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Enhanced regeneration of bone defects using sintered porous Ti6Al4V scaffolds incorporated with mesenchymal stem cells and platelet-rich plasma

RSC Advances ◽

10.1039/d0ra10215f ◽

2021 ◽

Vol 11 (9) ◽

pp. 5128-5138

Author(s):

Ji Li ◽

Ketao Wang ◽

Xiaowei Bai ◽

Qi Wang ◽

Ningyu Lv ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Bone Regeneration ◽

Platelet Rich Plasma ◽

Bone Defects ◽

Regeneration Of Bone

Porous Ti6AI4V scaffolds incorporated with MSC and PRP are more effective in enhancing the bone regeneration.

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Autogenous bone augmentation from the zygomatic alveolar crest: a volumetric retrospective analysis in the maxilla

International Journal of Implant Dentistry ◽

10.1186/s40729-020-00258-y ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Irina Kuster ◽

Livia Osterwalder ◽

Silvio Valdec ◽

Bernd Stadlinger ◽

Maximilian E. H. Wagner ◽

...

Keyword(s):

Gold Standard ◽

Donor Site ◽

Bone Defects ◽

Donor Site Morbidity ◽

Bone Volume ◽

Autogenous Bone ◽

Bone Augmentation ◽

Maximum Volume ◽

Alveolar Crest ◽

Good Access

Abstract Background Autogenous bone augmentation is the gold standard for the treatment of extended bone defects prior to implantation. Bone augmentation from the zygomatic crest is a valuable option with several advantages, but the current literature for this treatment is scant. The aim of this study was to evaluate the increase in bone volume after locoregional bone augmentation using autogenous bone from the zygomatic alveolar crest as well as the complications and success rate. Results Analysis of the augmented bone volume in seven patients showed a maximum volume gain of 0.97 cm3. An average of 0.54 cm3 of autogenous bone (SD 0.24 cm3; median: 0.54 cm3) was augmented. Implantation following bone augmentation was possible in all cases. Complications occurred in three patients. Conclusion The zygomatic alveolar crest is a valuable donor site for autogenous alveolar onlay grafting in a locoregional area such as the maxillary front. Low donor site morbidity, good access, and its suitable convexity make it a beneficial choice for autogenous bone augmentation.

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Study on X-ray Induced Two-Dimensional Thermal Shock Waves in Carbon/Phenolic

Materials ◽

10.3390/ma14133553 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3553

Author(s):

Dengwang Wang ◽

Yong Gao ◽

Sheng Wang ◽

Jie Wang ◽

Haipeng Li

Keyword(s):

Numerical Simulation ◽

Shock Wave ◽

Wave Propagation ◽

Thermal Shock ◽

Anisotropic Material ◽

Energy Deposition ◽

X Rays ◽

Two Dimensional ◽

X Ray ◽

Deposition Depth

Carbon/Phenolic (C/P), a typical anisotropic material, is an important component of aerospace and often used to protect the thermodynamic effects of strong X-ray radiation. In this paper, we establish the anisotropic elastic-plastic constitutive model, which is embedded in the in-house code “RAMA” to simulate a two-dimensional thermal shock wave induced by X-ray. Then, we compare the numerical simulation results with the thermal shock wave stress generated by the same strong current electron beam via experiment to verify the correctness of the numerical simulation. Subsequently, we discuss and analyze the rules of thermal shock wave propagation in C/P material by further numerical simulation. The results reveal that the thermal shock wave represents different shapes and mechanisms by the radiation of 1 keV and 3 keV X-rays. The vaporization recoil phenomenon appears as a compression wave under 1 keV X-ray irradiation, and X-ray penetration is caused by thermal deformation under 3 keV X-ray irradiation. The thermal shock wave propagation exhibits two-dimensional characteristics, the energy deposition of 1 keV and 3 keV both decays exponentially, the energy deposition of 1 keV-peak soft X-ray is high, and the deposition depth is shallow, while the energy deposition of 3 keV-peak hard X-ray is low, and the deposition depth is deep. RAMA can successfully realize two-dimensional orthotropic elastoplastic constitutive relation, the corresponding program was designed and checked, and the calculation results for inspection are consistent with the theory. This study has great significance in the evaluation of anisotropic material protection under the radiation of intense X-rays.

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Efficacy of a combination of simvastatin and poly(DL-lactic-co-glycolic acid) in stimulating the regeneration of Bone Defects

Materials Research ◽

10.1590/s1516-14392012005000159 ◽

2012 ◽

Vol 16 (1) ◽

pp. 215-220 ◽

Cited By ~ 4

Author(s):

Kyl Assaf ◽

Eliana Aparecida de Rezende Duek ◽

Newton Maciel Oliveira

Keyword(s):

Glycolic Acid ◽

Bone Defects ◽

Regeneration Of Bone

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High Speed, High Resolution pnCCDs as Two Dimensional Imaging Spectrometers for X-rays and Electrons

Microscopy and Microanalysis ◽

10.1017/s143192761400498x ◽

2014 ◽

Vol 20 (S3) ◽

pp. 652-653 ◽

Cited By ~ 1

Author(s):

H. Soltau ◽

R. Hartmann ◽

P. Holl ◽

S. Ihle ◽

H. Ryll ◽

...

Keyword(s):

High Resolution ◽

High Speed ◽

X Rays ◽

Two Dimensional

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APPLICATION OF DENDRIMER/PLASMID hBMP-2 COMPLEXES LOADED INTO β-TCP/COLLAGEN SCAFFOLD IN THE TREATMENT OF FEMORAL DEFECTS IN RATS

Biomedical Engineering Applications Basis and Communications ◽

10.4015/s1016237214500057 ◽

2014 ◽

Vol 26 (01) ◽

pp. 1450005 ◽

Cited By ~ 1

Author(s):

Tingwei Bao ◽

Huiming Wang ◽

Wentao Zhang ◽

Xuefeng Xia ◽

Jiabei Zhou ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Type I Collagen ◽

Cell Attachment ◽

Collagen Scaffold ◽

Bone Defects ◽

Bone Morphogenetic Protein 2 ◽

Porous Scaffolds ◽

Type I

Purpose: Plasmid loading into scaffolds to enhance sustained release of growth factors is an important focus of regenerative medicine. The aim of this study was to build gene-activated matrices (GAMs) and examine the bone augmentation properties. Methods: Generation 5 polyamidoamine dendrimers (G5 dPAMAM)/plasmid recombinant human bone morphogenetic protein-2 (rhBMP-2) complexes were immobilized into beta-tricalcium phosphate (β-TCP)/type I collagen porous scaffolds. After cultured with rat mesenchymal stem cells (rMSCs), transfection efficiencies were examined. The secretion of rhBMP-2 and alkaline phosphatase (ALP) were detected to evaluate the osteogenic properties. Scanning electron microscopy (SEM) was used to observe attachment and proliferation. Moreover, we applied these GAMs directly into freshly created segmental bone defects in rat femurs, and their osteogenic efficiencies were evaluated. Results: Released plasmid complexes were transfected into stem cells and were expressed, which caused osteogenic differentiations of rat mesenchymal stem cells (rMSCs). SEM analysis showed excellent cell attachment. Bioactivity of plasmid rhBMP-2 was maintained in vivo, and the X-ray observation, histological analysis and immunohistochemistry (IHC) of bone tissue demonstrated that the bone healing in segmental femoral defects was enhanced by implantation of GAMs. Conclusions: Such biomaterials offer therapeutic opportunities in critical-sized bone defects.

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