scholarly journals Bone remodeling effect of a chitosan and calcium phosphate-based composite

2019 ◽  
Vol 6 (4) ◽  
pp. 241-247 ◽  
Author(s):  
Lilja Kjalarsdóttir ◽  
Arna Dýrfjörd ◽  
Atli Dagbjartsson ◽  
Elín H Laxdal ◽  
Gissur Örlygsson ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Formation ◽  
Bone Remodeling ◽  
Morphological Changes ◽  
Drill Hole ◽  
New Bone Formation ◽  
Sprague Dawley ◽  
Time Points ◽  
Formation Pattern ◽  
Rat Mandible

Abstract Chitosan is a biocompatible polymer that has been widely studied for tissue engineering purposes. The aim of this research was to assess bone regenerative properties of an injectable chitosan and calcium phosphate-based composite and identify optimal degree of deacetylation (%DDA) of the chitosan polymer. Drill holes were generated on the left side of a mandible in Sprague-Dawley rats, and the hole was either left empty or filled with the implant. The animals were sacrificed at several time points after surgery (7–22 days) and bone was investigated using micro-CT and histology. No significant new bone formation was observed in the implants themselves at any time points. However, substantial new bone formation was observed in the rat mandible further away from the drill hole. Morphological changes indicating bone formation were found in specimens explanted on Day 7 in animals that received implant. Similar bone formation pattern was seen in control animals with an empty drill hole at later time points but not to the same extent. A second experiment was performed to examine if the %DDA of the chitosan polymer influenced the bone remodeling response. The results suggest that chitosan polymers with %DDA between 50 and 70% enhance the natural bone remodeling mechanism.

Effect of Particle Size on New Bone Formation In Vivo Using Calcium Phopshate Glass

2007 ◽  
Vol 330-332 ◽  
pp. 165-168
Author(s):  
Hyun Ju Moon ◽  
Racquel Z. LeGeros ◽  
Kyoung Nam Kim ◽  
Kwang Mahn Kim ◽  
Seong Ho Choi ◽  
...  
Keyword(s):  
Particle Size ◽  
Calcium Phosphate ◽  
Bone Formation ◽  
Phosphate Glass ◽  
Glass Powder ◽  
New Bone Formation ◽  
Sprague Dawley ◽  
Constant Weight ◽  
Calvarial Defects

The purpose of this study was to compare the bone regenerative effect of calcium phosphate glass according to the particle size in vivo. We prepared two different sizes, that is 400 μm and 40 μm, of calcium phosphate glass powder using the system CaO-CaF2-P2O5-MgO-ZnO. Critical-sized calvarial defects were created in 60 male Sprague-Dawley rats. The animals were divided into 3 groups of 20 animals each. Each defect was filled with a constant weight of 0.5 g calcium phosphate glass powder mixed with saline. As controls, the defect was left empty. The rats were sacrificed 2 or 8 weeks after postsurgery, and the results were evaluated using histological as well as histomorphometrical studies. The particle size of the calcium phosphate was crucial; 400 μm particles promoted new bone formation, while 40 μm particles inhibited it because of severe inflammation.

scholarly journals Biocompatibility and Bone Formation of Flexible, Cotton Wool-like PLGA/Calcium Phosphate Nanocomposites in Sheep

2011 ◽  
Vol 5 (1) ◽  
pp. 63-71 ◽  
Author(s):  
Oliver D Schneider ◽  
Dirk Mohn ◽  
Roland Fuhrer ◽  
Karina Klein ◽  
Käthi Kämpf ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Formation ◽  
Antimicrobial Properties ◽  
Drill Hole ◽  
Bone Defects ◽  
Long Bone ◽  
Minimal Amount ◽  
Cotton Wool

Background: The purpose of this preliminary study was to assess the in vivo performance of synthetic, cotton wool-like nanocomposites consisting of a biodegradable poly(lactide-co-glycolide) fibrous matrix and containing either calcium phosphate nanoparticles (PLGA/CaP 60:40) or silver doped CaP nanoparticles (PLGA/Ag-CaP 60:40). Besides its extraordinary in vitro bioactivity the latter biomaterial (0.4 wt% total silver concentration) provides additional antimicrobial properties for treating bone defects exposed to microorganisms. Materials and Methods: Both flexible artificial bone substitutes were implanted into totally 16 epiphyseal and metaphyseal drill hole defects of long bone in sheep and followed for 8 weeks. Histological and histomorphological analyses were conducted to evaluate the biocompatibility and bone formation applying a score system. The influence of silver on the in vivo performance was further investigated. Results: Semi-quantitative evaluation of histology sections showed for both implant materials an excellent biocompatibility and bone healing with no resorption in the adjacent bone. No signs of inflammation were detectable, either macroscopically or microscopically, as was evident in 5 µm plastic sections by the minimal amount of inflammatory cells. The fibrous biomaterials enabled bone formation directly in the centre of the former defect. The area fraction of new bone formation as determined histomorphometrically after 8 weeks implantation was very similar with 20.5 ± 11.2 % and 22.5 ± 9.2 % for PLGA/CaP and PLGA/Ag-CaP, respectively. Conclusions: The cotton wool-like bone substitute material is easily applicable, biocompatible and might be beneficial in minimal invasive surgery for treating bone defects.

Histopathological assessment of healing process using an amniotic membrane in osteotomy defects caused by piezosurgery and conventional surgery in rats

2020 ◽  
Author(s):  
Semsettin Ilker ◽  
Alper Ilker ◽  
Efe Sivrikaya
Keyword(s):  
Bone Formation ◽  
Amniotic Membrane ◽  
Healing Process ◽  
Outcome Variable ◽  
New Bone Formation ◽  
Sprague Dawley ◽  
Conventional Surgery ◽  
Surgical Methods ◽  
Healing Score ◽  
Building Level

Abstract There is a paucity of studies aimed to compare the healing process of piezosurgery with conventional surgery. This study evaluated the histopathological assessment of healing process in osteotomy defects caused by these surgical methods in rats using an amniotic membrane (hAM). In this randomized controlled experimental study, there were 2 main groups: group 1 (Piezosurgery method-right tibia) and group 2 (Conventional surgery method-left tibia) and subgroups determined by the sacrification periods on the 7th (n = 20) and 21st days (n = 20). hAM was used in all groups. The primary outcome variable was new bone formation, while inflammation, necrosis, fibrotic tissue formation in the defective zone were secondary outcomes. 40 male Sprague Dawley rats were used. The 7th day fibrosis levels and the 7th new bone-building level of the group who underwent piezosurgery were found to be significantly higher than those of the group undergoing conventional surgery (p < 0.05) and the 21st new bone-building level was significantly lower than conventional surgery. In all rats, on the 21st day, there were statistically significant decreases in inflammation, fibrosis, and increases in the healing score (p < 0.05). Also, there was no statistically difference in new bone formation between 7st and 21st days (p > 0.05). The choice of conventional surgery when applying with hAM increases the new bone building in the late period.

The Application of Scanning Acoustic Microscopy in a Bone Remodeling Study

1995 ◽  
Vol 117 (3) ◽  
pp. 286-292 ◽  
Author(s):  
Sheu-Jane Shieh ◽  
M. C. Zimmerman ◽  
N. A. Langrana
Keyword(s):  
Bone Formation ◽  
Bone Remodeling ◽  
Acoustic Impedance ◽  
Basic Structure ◽  
Acoustic Microscopy ◽  
Scanning Acoustic Microscopy ◽  
New Bone Formation ◽  
Primary Mechanism ◽  
Low Modulus ◽  
Surface Remodeling

Scanning acoustic microscopy (SAM) was used in the evaluation of bone remodeling around a cylindrical unicortical defect. SAM is a technique for the nondestructive evaluation of materials, and has only recently been employed as an orthopaedic research tool. The utility of SAM was demonstrated by using it to measure an elastic property known as acoustic impedance. Specifically, the acoustic impedance of bone formed by remodeling around a cylindrical defect was measured. The defects were filled with either a low modulus “void” or rigid inclusion to create various states of stress in the bone in the vicinity of the defect. After six months of implantation of the inclusions in the sheep metatarsal, new bone formation on periosteal and endosteal surfaces about the defect region was observed. These regions of new bone were less stiff and had 18.0 ± 6.5% lower acoustic impedance than the pre-existing bone in the intracortical region of the metatarsal. There was no difference in the degree of new bone formation about void and rigid inclusions. Both underwent significant adaptational changes in response to the elevated stress about the defect. These changes affected the basic structure of the bone cross-section at the level of the defect and effectively reduced the stress levels about the defect. By using SAM to measure acoustic impedance, it was seen that little internal remodeling occurred in the intracortical region. Hence, the primary mechanism of strain-induced bone remodeling observed in this experimental model was surface remodeling.

In Vitro and In Vivo Evaluation Of Calcium Phosphate Bone Graft Substitutes

2010 ◽  
Vol 654-656 ◽  
pp. 2065-2070
Author(s):  
Ho Yeon Song ◽  
Young Hee Kim ◽  
Jyoti M. Anirban ◽  
In Seon Byun ◽  
Kyung A Kwak ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Formation ◽  
Bone Graft ◽  
Cellular Proliferation ◽  
New Bone Formation ◽  
Hydroxy Apatite ◽  
Defect Sites ◽  
Bone Graft Substitutes

Calcium phosphate ceramics such as hydroxy apatite (HA), β-tricalcium phosphate (β-TCP) and bicalcium phosphate (BCP) have been used as a bone graft biomaterial because of their good biocompatibility and similarity of chemical composition to natural bones. To increase the mechanical and osteoconductive properties, the granules and spongy type porous bone graft substitutes were prepared by fibrous monolithic process and polyurethane foam replica methods, respectively. The pore sizes obtained using these approaches ranged between 100-600 µm. The cytotoxicity, cellular proliferation, differentiation and ECM deposition on the bone graft substitutes were observed by SEM and confocal microscopy. Moreover, the scaffolds were implanted in the rabbit femur. New bone formation and biodegradation of bone graft were observed through follow-up X-ray, micro-CT analysis and histological findings. After several months (2, 3, 6, 12 and 24 months) of implantation, new bone formation and ingrowths were observed in defect sites of the animal by CaP ceramics and 2 to 3 times higher bone ingrowths were confirmed than that of the normal trabecular bones in terms of total bone volume (BV).

Bone Marrow Autograft Associated to Macroporous Biphasic Calcium Phosphate for Bone Substitution in an Animal Model of Sequels of Radiotherapy

2005 ◽  
Vol 284-286 ◽  
pp. 285-288
Author(s):  
Oliver Malard ◽  
Jean Michel Bouler ◽  
Jerome Guicheux ◽  
Olivier Gauthier ◽  
E. Lerouxel ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Calcium Phosphate ◽  
Bone Formation ◽  
Biphasic Calcium Phosphate ◽  
Bone Repair ◽  
Major Surgery ◽  
Graft Versus Host Reaction ◽  
Bone Reconstruction ◽  
New Bone Formation ◽  
Study Results

Bone invasion is common in case of Squamous Cell Carcinomas (SCC) of the upper aero-digestive tract. Radiotherapy is required in addition to large surgical tumor removal. This treatment usually generates irreversible injuries on the reparation properties of the tissues, especially on bone. The quality of life of patients undergoing major surgery and radiotherapy in maxillary and mandible areas is reduced, but could be improved by bone reconstruction. The aim of this study was to evaluate the bone reconstruction possibilities by Macroporous Biphasic Calcium-Phosphate (MBCPÔ). The MBCP substitute was evaluated as granules and associated to autologous bone marrow (BM) graft in irradiated areas, in an inbreeding rodent model. Radiation sequels were created on inferior members of half of the rats. 3 weeks later, 3-mm osseous defects were created on each animal. The inbreeding model allows BM to be grafted without graft-versus-host reaction. Defects were filled either with MBCP alone, BM alone or a mixture of MBCP and BM. Six weeks after implantation, animals were sacrificed: bone repair and ceramic degradation were evaluated by qualitative and quantitative study. Results showed that bioceramics were well osteointegrated. Filling the defects with BM alone showed a significant increased of newly-formed bone formation but only after irradiation, whereas filling defects with MBCP alone increased new-bone formation only without previous irradiation. Associating MBCP to BM provided the best new-bone formation rates after irradiation. Degradation of the ceramic was the most important in case of BM grafting. This study demonstrated that BM added to MBCP constitute an appropriate material to be considered in case of bone defect occurring in irradiated tissue, and could be foreseen for use after bone removal for oncologic obligations.

Sign in / Sign up

Export Citation Format

Share Document