Bone formation and bone implant contact in diabetic patients; A histomorphometry human study

This study aimed to quantify new bone formation in the femurs of diabetic Wistar rats. Over an eight-week period, MTI-MP® implants were evaluated in control rats and in diabetic rats. At several points during this period, various markers for bone deposit were introduced. The material was observed under fluorescent light microscopy. New bone formation in periosteal and cortical regions linked to the implant did not vary significantly between the groups. However, there were significant differences in total new bone formation in the medullar canal and in bone/implant contact area in the medullar portion. Bone deposits attached to the surface of the temporary implants demonstrated that they are biocompatible and capable of osseointegration.

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Influence of Simvastatin-Loaded Implants on Osseointegration in an Ovariectomized Animal Model

BioMed Research International ◽

10.1155/2015/831504 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 8

Author(s):

Wen Fang ◽

Shifang Zhao ◽

Fuming He ◽

Li Liu ◽

Guoli Yang

Keyword(s):

Animal Model ◽

Bone Formation ◽

Electrochemical Process ◽

New Bone Formation ◽

Bone Implant ◽

Natural Bone ◽

Porous Implant ◽

Bone Implant Contact ◽

Dose Effects ◽

Ovariectomized Animal

The success of bone implants in the presence of osteoporosis is limited by lack of osseointegration between the implant and the natural bone. This study applied an electrochemical process to deposit simvastatin-nanohydroxyapatite (HA) coatings on porous implant surfaces and investigated the effects of these simvastatin-HA coatings on implant surfaces in an animal model of osteoporosis. In this study, simvastatin-HA coated implants were inserted into the tibia of osteoporotic rats. After 2, 4, and 12 weeks, tissue was retrieved for histomorphometric evaluation. The results indicated that the simvastatin-HA coatings increased bone-implant contact and new bone formation around implant surfaces. In conclusion, implants loaded with simvastatin by an electrochemical process improved implant osseointegration in osteoporotic rats. Furthermore, the increased concentration of simvastatin could affect the osseointegration, but the dose-effects also need further investigation.

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In Vivo and In Vitro Evaluation of Coated HAp Films with Different Surface Morphology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.539-543.710 ◽

2007 ◽

Vol 539-543 ◽

pp. 710-715

Author(s):

Kotaro Kuroda ◽

Ryoichi Ichino ◽

Masazumi Okido

Keyword(s):

Bone Formation ◽

Surface Morphology ◽

New Bone Formation ◽

Contact Ratio ◽

Bone Implant ◽

Ft Ir ◽

Mouse Osteoblast ◽

Surface Morphologies

Hydroxyapatite (HAp) coatings were formed on cp titanium plates and rods by the thermal substrate method in an aqueous solution that included 0.3 mM Ca(H2PO4)2 and 0.7 mM CaCl2. The coating experiments were conducted at 40-140 oC and pH = 8 for 15 or 30 min. The properties for the coated samples were studied using XRD, EDX, FT-IR, and SEM. All the specimens were covered with HAp, which had different surface morphologies such as net-like, plate-like and needle-like. After cleaning and sterilization, all the coated specimens were subjected to in vivo and vitro testing. In the in vitro testing, the mouse osteoblast-like cells (MC3T3-E1) were cultured on the coated and non-coated specimens for up to 30 days. Moreover, the specimens (φ2 x 5 mm) were implanted in rats femoral for up to 8 weeks, the osseoinductivity on them were evaluated. In in vitro evaluations, there were not significant differences between the different surface morphologies. In in vivo evaluations, however, two weeks postimplantation, new bone formed on both the HAp coated and non-coated titanium rods in the cancellous and cortical bone. The bone-implant contact ratio, which was used for the evaluation of new bone formation, was significantly dependent on the surface morphology of the HAp, and the results demonstrated that the needle-like coating appears to promote rapid bone formation.

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Therapeutic effects of Hypoxia-Inducible Factor-1α (HIF-1α) on bone formation around implants in diabetic mice

10.1101/392670 ◽

2018 ◽

Author(s):

Sang-Min Oh ◽

Jin-Su Shin ◽

Il-Koo Kim ◽

Jae-Seung Moon ◽

Jung-Ho Kim ◽

...

Keyword(s):

Bone Formation ◽

Rna Sequencing ◽

Normal Mouse ◽

Target Genes ◽

Hypoxia Inducible Factor ◽

Diabetic Mouse ◽

Differentially Expressed ◽

Diabetic Patients ◽

Diabetic Mice ◽

Hypoxia Inducible Factor 1Α

AbstractPatients with uncontrolled diabetes are susceptible to implant failure due to impaired bone metabolism. Hypoxia-Inducible Factor 1α (HIF-1α), a transcription factor that is up-regulated in response to reduced oxygen condition during the bone repair process after fracture or osteotomy, is known to mediate angiogenesis and osteogenesis. However, its function is inhibited under hyperglycemic conditions in diabetic patients. The aim of this study is to evaluate the effects of exogenous HIF-1α on bone formation around implants by applying HIF-1α to diabetic mice via a novel PTD-mediated DNA delivery system. Smooth surface implants (1mm in diameter; 2mm in length) were placed in the both femurs of diabetic and normal mice. HIF-1α and placebo gels were injected to implant sites of the right and left femurs, respectively: Normal mouse with HIF-1α gel (NH), Normal mouse with placebo gel (NP), Diabetic mouse with HIF-1α gel (DH), and Diabetic mouse with placebo gel (DP). RNA sequencing was performed 4 days after surgery. Based on RNA sequencing, Differentially Expressed Genes (DEGs) were identified and HIF-1α target genes were selected. Histologic and histomorphometric results were evaluated 2 weeks after the surgery. The results showed that bone-to-implant contact (BIC) and bone volume (BV) were significantly greater in the DH group than the DP group (p < 0.05). A total of 216 genes were differentially expressed in DH group compared to DP group. On the other hand, there were 95 DEGs in the case of normal mice. Twenty-one target genes of HIF-1α were identified in diabetic mice through bioinformatic analysis of DEGs. Among the target genes, NOS2, GPNMB, CCL2, CCL5, CXCL16 and TRIM63 were manually found to be associated with wound healing-related genes. In conclusion, local administration of HIF-1α via PTD may help bone formation around the implant and induce gene expression more favorable to bone formation in diabetic mice.

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Abstract P031: Effect of Exercise on Function and Differentiation of Adipose Tissue Derived Mesenchymal Stromal Cells (MSCs)

Circulation ◽

10.1161/circ.137.suppl_1.p031 ◽

2018 ◽

Vol 137 (suppl_1) ◽

Author(s):

Nabanita Kundu ◽

Cleyton Domingues ◽

Peter Kokkinos ◽

Eric Nylen ◽

Sabyasachi Sen

Keyword(s):

Gene Expression ◽

Alkaline Phosphatase ◽

Bone Formation ◽

Aerobic Exercise ◽

Stromal Cells ◽

Exercise Intervention ◽

Diabetic Patients ◽

Differentiation Potential ◽

Post Exercise ◽

Bone Formation Markers

Approximately 422 million people have diabetes worldwide (2014) and it is predicted that diabetes will rise by nearly 54% by 2030. Aerobic exercise is known to show positive effect on health of diabetic and pre diabetic patients. The effect of exercise has been studied extensively using plasma biochemistry but cellular data is scares. Previously, we have shown endothelial progenitor cells (EPCs) can act as a strong cellular biomarker of endothelial function following aerobic exercise as an intervention. In this study, we are examining the effect of aerobic exercise on adipocyte derived MSCs to study stromal cell differentiation and as a cellular surrogate of fat metabolism. Methods: Overweight and obese subjects (n=5) were enrolled in a 12 week exercise intervention study. The biweekly exercise sessions were supervised by a trained exercise physiologist and consisted of a 1 hour sessions that included warm-up and cool-down and 30 min of combined aerobic and resistance training at an exercise intensity of 50-80% of heart rate reserve. Physical and biochemical parameters were tested pre and post exercise. Subcutaneous abdominal fat biopsies were obtained and fat derived stromal cells were cultured in vitro for 2-3 weeks. MSCs were analyzed for mRNA gene expression (qRT-PCR) and cellular oxygen consumption rate (OCR), pre and post 12 week exercise. Results: With exercise, A1C reduced significantly. An increase of METs was also noticed post exercise. Both basal and maximal respiration increased significantly post exercise when compared with commercially obtained MSCs. Simultaneously, mitochondrial genes COX4 and ATP5B (p= 0.01, 1.4 fold, 0.02, 1.5 fold respectively), Glucose transporter, GLUT1 (p=0.04, 1.8 fold), antioxidants GPX3 and CAT (p= 0.01, 3.2 fold and p=0.04, 1.5 fold respectively) upregulated whereas pro-inflammatory cyclo-oxygenase-2 (p=0.04, 2.5 fold) gene reduced significantly, post exercise. Regarding differentiation potential of multipotent MSCs, post exercise, we noted enhanced expression of bone markers such Alkaline Phosphatase (p= 0.03, 2.7 fold) BGLAP and RUNX2 (1.3 and 1.2 fold) and also for collagen marker COL2 (2.4 fold) expression. For adipogenic differentiation potential PPARG mRNA expression was reduced. Interestingly, serum value of osteocalcin increased significantly from 15.0 (5.5) to 16.3(6.1) ng/ml (9% increase, p=0.03) with 1% increase in bone alkaline phosphatase level, post exercise. Conclusion: We conclude that exercise augments cellular glucose transporters (GLUT1), anti-oxidants and reduce MSC inflammation and up-regulates mitochondrial function and gene expression profile of MSCs. Increased serum value of osteocalcin complement increased gene expression of bone formation markers indicating a cross talk between fat derived MSCs and bone formation, post exercise.

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Strontium-Loaded Nanotubes of Ti–24Nb–4Zr–8Sn Alloys for Biomedical Implantation

Journal of Biomedical Nanotechnology ◽

10.1166/jbn.2021.3160 ◽

2021 ◽

Vol 17 (9) ◽

pp. 1812-1823

Author(s):

Fei Liu ◽

Xinyu Wang ◽

Shujun Li ◽

Yiheng Liao ◽

Xinxin Zhan ◽

...

Keyword(s):

Early Stage ◽

Contact Rate ◽

Hard Tissue ◽

Tissue Slices ◽

Bone Implant ◽

P Elements ◽

Low Elastic Modulus ◽

Bone Implant Contact

Ti–24Nb–4Zr–8Sn (Ti2448) alloys, with a relatively low elastic modulus and unique mechanical properties, are desirable materials for oral implantation. In the current study, a multifaceted strontium-incorporating nanotube coating was fabricated on a Ti2448 alloy (Ti2-NTSr) through anodization and hydrothermal procedures. In vitro, the Ti2-NTSr specimens demonstrated better osteogenic properties and more favorable osteoimmunomodulatory abilities. Moreover, macrophages on Ti2-NTSr specimens could improve the recruitment and osteogenic differentiation of osteoblasts. In vivo, dense clots with highly branched, thin fibrins and small pores existed on the Ti2-NTSr implant in the early stage after surgery. Analysis of the deposition of Ca and P elements, hard tissue slices and the bone-implant contact rate (BIC%) of the Ti2-NTSr implants also showed superior osseointegration. Taken together, these results demonstrate that the Ti2-NTSr coating may maximize the clinical outcomes of Ti2448 alloys for implantation applications.

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Vertical Bone Implant Contact Around Anterior Immediate Implants and Their Stability After Using Either Alloplast or L-PRF or Both in Peri-Implant Gap: A Prospective Randomized Trial

Journal of Maxillofacial and Oral Surgery ◽

10.1007/s12663-020-01426-8 ◽

2020 ◽

Author(s):

Md Shahbaz Alam ◽

Arjun Dhiman ◽

Veena Jain ◽

Ongkila Bhutia ◽

Gunjan Pruthi

Keyword(s):

Randomized Trial ◽

Prospective Randomized Trial ◽

Bone Implant ◽

Bone Implant Contact ◽

Immediate Implants

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In VivoMicroCT Monitoring of Osteomyelitis in a Rat Model

BioMed Research International ◽

10.1155/2015/587857 ◽

2015 ◽

Vol 2015 ◽

pp. 1-12 ◽

Cited By ~ 13

Author(s):

Vincent A. Stadelmann ◽

Inga Potapova ◽

Karin Camenisch ◽

Dirk Nehrbass ◽

R. Geoff Richards ◽

...

Keyword(s):

Morphological Changes ◽

Orthopedic Implants ◽

Surgical Removal ◽

Element Analysis ◽

Bone Implant ◽

Bone Implant Contact ◽

Bone Changes ◽

Bone Fraction ◽

Microct Imaging

Infection associated with orthopedic implants often results in bone loss and requires surgical removal of the implant. The aim of this study was to evaluate morphological changes of bone adjacent to a bacteria-colonized implant, with the aim of identifying temporal patterns that are characteristic of infection. In anin vivostudy with rats, bone changes were assessed usingin vivomicroCT at 7 time points during a one-month postoperative period. The rats received either a sterile orStaphylococcus aureus-colonized polyetheretherketone screw in the tibia. Bone-implant contact, bone fraction, and bone changes (quiescent, resorbed, and new bone) were calculated from consecutive scans and validated against histomorphometry. The screw pullout strength was estimated from FE models and the results were validated against mechanical testing. In the sterile group, bone-implant contact, bone fraction, and mechanical fixation increased steadily until day 14 and then plateaued. In the infected group, they decreased rapidly. Bone formation was reduced while resorption was increased, with maximum effects observed within 6 days. In summary, the model presented is capable of evaluating the patterns of bone changes due to implant-related infections. The combined use of longitudinalin vivomicroCT imaging and image-based finite element analysis provides characteristic signs of infection within 6 days.

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Anodisation Increases Integration of Unloaded Titanium Implants in Sheep Mandible

BioMed Research International ◽

10.1155/2015/857969 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Warwick J. Duncan ◽

Min-Ho Lee ◽

Tae-Sung Bae ◽

Sook-Jeong Lee ◽

Jennifer Gay ◽

...

Keyword(s):

Titanium Implant ◽

Titanium Implants ◽

Implant Stability ◽

Bone Implant ◽

Implant Stability Quotient ◽

Phosphate Ions ◽

Surface Control ◽

Bone Implant Contact ◽

The Subject ◽

Clinically Significant

Spark discharge anodic oxidation forms porous TiO2films on titanium implant surfaces. This increases surface roughness and concentration of calcium and phosphate ions and may enhance early osseointegration. To test this, forty 3.75 mm × 13 mm titanium implants (Megagen, Korea) were placed into healed mandibular postextraction ridges of 10 sheep. There were 10 implants per group: RBM surface (control), RBM + anodised, RBM + anodised + fluoride, and titanium alloy + anodised surface. Resonant frequency analysis (RFA) was measured in implant stability quotient (ISQ) at surgery and at sacrifice after 1-month unloaded healing. Mean bone-implant contact (% BIC) was measured in undemineralised ground sections for the best three consecutive threads. One of 40 implants showed evidence of failure. RFA differed between groups at surgery but not after 1 month. RFA values increased nonsignificantly for all implants after 1 month, except for controls. There was a marked difference in BIC after 1-month healing, with higher values for alloy implants, followed by anodised + fluoride and anodised implants. Anodisation increased early osseointegration of rough-surfaced implants by 50–80%. RFA testing lacked sufficient resolution to detect this improvement. Whether this gain in early bone-implant contact is clinically significant is the subject of future experiments.

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