Immobilization of BMP‐2, BMP‐7 and alendronic acid on titanium surfaces: Adhesion, proliferation and differentiation of bone marrow‐derived stem cells

This study analyzed the influence of titanium (TiO2 ) surface modifications with two osteogenic proteins (BMP-2, BMP-7) and an anti-osteoclastic drug (alendronic acid [AA]) on sandblasted/acid-etched (SLA) and plain TiO2 (PT) on cell adhesion, proliferation and differentiation (alkaline phosphatase [AP] and osteocalcin [OC]) of bone-marrow derived stem cells (BMSCs) after 1, 3 and 7 days in-vitro. Initially, AA surfaces showed the highest cell number and surface coverage. At day 3 and 7, BMP and AA-modified surfaces exhibited a significantly enhanced cell growth. For proliferation, at days 3 and 7, an enhancement on BMP-2, BMP-7 and AA-surfaces was seen. At day 7, SLA also showed a higher p…

Priming with proangiogenic growth factors and endothelial progenitor cells improves revascularization in linear diabetic wounds

In the present study, we investigated whether proangiogenic growth factors and endothelial progenitor cells (EPCs) induce favourable effects on cutaneous incisional wound healing in diabetic mice. The proangiogenic effects of human EPCs were initially analyzed using a HUVEC in vitro angiogenesis assay and an in vivo Matrigel assay in nude mice (n=12). For the diabetic wound model, 48 Balb/c mice with streptozotocin (STZ)-induced diabetes were divided randomly into 4 groups (12 mice in each group). Subsequently, 3, 5 and 7 days before a 15-mm full-thickness incisional skin wound was set, group 1 was pre-treated subcutaneously with a mixture of vascular endothelial growth factor (VEGF)/basic …

Elastin Cables Define the Axial Connective Tissue System in the Murine Lung

The axial connective tissue system is a fiber continuum of the lung that maintains alveolar surface area during changes in lung volume. Although the molecular anatomy of the axial system remains undefined, the fiber continuum of the lung is central to contemporary models of lung micromechanics and alveolar regeneration. To provide a detailed molecular structure of the axial connective tissue system, we examined the extracellular matrix of murine lungs. The lungs were decellularized using a 24 hr detergent treatment protocol. Systematic evaluation of the decellularized lungs demonstrated no residual cellular debris; morphometry demonstrated a mean 39 ± 7% reduction in lung dimensions. Scanni…

Possible Implications for Improved Osteogenesis? The Combination of Platelet-Rich Fibrin With Different Bone Substitute Materials

Bone substitute materials (BSM) are widely used in oral regeneration, but sufficient angiogenesis is crucial for osteogenesis. The combination of BSM with autologous thrombocyte concentrations such as platelet-rich fibrin (PRF) may represent a clinical approach to overcome this limitation. This study analyzes the early influence on osteoblast (HOB) in vitro. Here, four different BSM (allogeneic, alloplastic, and two of xenogeneic origin) were combined with PRF. After the incubation with osteoblasts for 24 h, cell viability, migration, and proliferation were assessed. Next, marker of proliferation, migration, and differentiation were evaluated on gene and protein levels in comparison to the …

Influence of Different Bisphosphonates on Keratinocytes, HUVEC, Fibroblasts and Osteoblasts in-vitro

Investigation of inhibitory effects on EPC-mediated neovascularization by different bisphosphonates for cancer therapy.

Bisphosphonates (BPs) are potent drugs, used in metastatic cancer-like prostate or breast carcinoma. In recent studies, besides reduced bone remodeling, influences on angiogenesis and neovascularization were reported. Since BPs have the tendency to accumulate in the bones, the biological effect of various nitrogen- and non-nitrogen BPs on endothelial progenitor cells (EPCs) that originated from bone marrow and mobilized under physiological and pathophysiological conditions, such as tumor neovascularization, was investigated. EPCs subsequent to 72-h treatment with different concentrations of bisphosphonates comprised the non-nitrogen-containing BP clodronate and the nitrogen-containing BPs i…

The prevalence of human papilloma virus (HPV) infections in oral squamous cell carcinomas: a retrospective analysis of 88 patients and literature overview.

In addition to tobacco and alcohol consumption, the two main risk factors for oral squamous cell carcinoma (OSCC), recent studies have revealed infections with human papilloma virus (HPV) as an additional risk factor for OSCC development. In the field of head and neck malignancies, the prevalence of HPV infections in oropharyngeal cancer (OC) ranges in different studies up to 84%. While HPV infection is discussed as an independent risk factor in this region, its distinguished role in carcinogenesis of tumours localized to the oral cavity remains still uncertain. In this study, we analysed the HPV status in 88 consecutive patients with OSCCs localized anterior of the palatoglossal arch who w…

The Influence of Hyaluronic Acid Biofunctionalization of a Bovine Bone Substitute on Osteoblast Activity In Vitro

Bovine bone substitute materials (BSMs) are used for oral bone regeneration. The objective was to analyze the influence of BSM biofunctionalization via hyaluronic acid (HA) on human osteoblasts (HOBs). BSMs with ± HA were incubated with HOBs including HOBs alone as a negative control. On days 3, 7 and 10, cell viability, migration and proliferation were analyzed by fluorescence staining, scratch wound assay and MTT assay. On days 3, 7 and 10, an increased cell viability was demonstrated for BSM+ compared with BSM− and the control (each p ≤ 0.05). The cell migration was enhanced for BSM+ compared with BSM− and the control after day 3 and day 7 (each p ≤ 0.05). At day 10, an accelerated wound…

Acceleration of image filtering algorithms for 3D visualization of murine lungs using dataflow engines

Image filtering is one of the most common and important tasks in image processing applications. In this paper, image processing using a mean filtering algorithm combined with thresholding and binarization algorithms for the 3D visualization and analysis of murine lungs is explained. These algorithms are then mapped on the Maxler's MAX2336B Dataflow Engine (DFE) to significantly increase calculation speed. Several different DFE configurations were tested and each yielded different performance characteristics. Optimal algorithm calculation speed was up to 30 fold baseline calculation speed.

Bisphosphonates affect migration ability and cell viability of HUVEC, fibroblasts and osteoblasts in vitro

Oral Diseases (2011) 17, 194–199 Objectives:  Bisphosphonate-associated osteonecrosis of the jaw (BP-ONJ) is a side effect in patients being treated with bisphosphonates. The bisphosphonates most often associated with BP-ONJ are the highly potent nitrogen-containing bisphosphonates, e.g. pamidronate or zoledronate. In terms of BP-ONJ aetiology, several theories are being discussed: inhibition of bone remodelling, effect on soft tissues, and antiangiogenic effect of bisphosphonates. The aim of this in vitro study was to investigate the effect of different potent bisphosphonates on osteoblasts, fibroblasts and human umbilicord vein endothelial cells (HUVEC). Materials and methods:  Three nitr…

Geranylgeraniol - a new potential therapeutic approach to bisphosphonate associated osteonecrosis of the jaw.

Bisphosphonate associated osteonecrosis of the jaw (BP-ONJ) is one of the main side effects of bisphosphonate therapy (BPT). To date, there is no effective therapy of the BP-ONJ. Nitrogen-containing bisphosphonates (N-BPs) are particularly able to inhibit pyrophosphate synthase (FPPS) in the mevalonate pathway (MVP). Consequent of decreased synthesis of the metabolite Geranylgeraniol (GGOH) is believed to largely account for the development of BP-ONJ. Negative effect of N-BPs could be shown, resulting in decreased viability and migration capacity of different cell types of hard and soft tissues such as osteoblasts, fibroblast und endothelial cells. Aim of our in vitro study was to demonstra…

Effects of a low-level diode laser on oral keratinocytes, oral fibroblasts, endothelial cells and osteoblasts incubated with bisphosphonates: An

Bisphosphonate-associated osteonecrosis of the jaw may have multiple causes, including altered bone remodeling, angiogenesis inhibition and impact of bisphosphonate on the soft tissues. Successful treatment is difficult. As a positive effect of low-level laser application on wound healing is well known, an in vitro study was designed to analyze the effect of low-level laser (280 mW, 670 nm) treatment on keratinocytes, fibroblasts, endothelial cells and osteoblasts treated with clodronate, ibandronate, pamidronate or zoledronate. Pure irradiation had a positive effect on cell viability, whereas bisphosphonate treatment had a negative impact. Viability was significantly increased in cells tre…

Osseous response on linear and cyclic RGD-peptides immobilized on titanium surfaces in vitro and in vivo

Biomimetic surface modifications of titanium implants using the Arg-Gly-Asp-sequence (RGD) are promising to accelerate bone healing in cases of medical implants. Therefore, we compared the impact of linear and cyclic RGD (l- and c-RGD) covalently coupled onto titanium surfaces on the osseous response in vitro and in vivo. In vitro, osteoblasts' behaviour on different surfaces (unmodified, amino-silanized (APTES), l- and c-RGD) was analysed regarding adhesion (fluorescence microscopy), proliferation (resazurin stain) and differentiation (RT-PCR on alkaline phosphatase (AP) & osteocalcin (OC)). In vivo, osteosynthesis screws (unmodified n=8, l-RGD n=8, c-RGD n=8) were inserted into the proxim…

In vitro and in vivo characterization of porcine acellular dermal matrix for gingival augmentation procedures

Recently, porcine acellular dermal matrix (PADM) has been proposed as a possible alternative to autogenous grafts in periodontal plastic surgery. The aim of the present study was to investigate the in vitro responses of four different oral cell lines cultured on a novel PADM. Furthermore, tissue reaction to PADM was evaluated histologically after subcutaneous implantation in mice.Human gingival fibroblasts (HGF), human osteoblast-like cells, human umbilical vein endothelial cells and human oral keratinocytes (HOK) were cultured and transferred on to the PADM. A tissue culture polystyrene surface served as the control. The viability of all tested cell lines on PADM was measured by using the …

Influence of Different Rehydration Protocols on Biomechanical Properties of Allogeneic Cortical Bone Plates: A Combined in-vitro/in-vivo Study

Introduction: Allogeneic cortical bone plates (CP) are used for alveolar ridge augmentation. Since CP are freeze-dried and dehydrated during processing, the breaking strength (BS) and the flexibility (FX) are reduced, resulting in a relevant risk for plate fractures during insertion. The aim of this study was to evaluate the influence of rehydration time on the biomechanical properties (BS & FX) of CP in-vitro and in vivo.Material and Methods: 40 CP were randomly divided into four experimental groups. (A) untreated control (n = 10), rehydration for 10 (B), 30 (C) and 60 (D) minutes in 0.9% saline solution (n = 10 each). BS [Newton, N] and FX [mm] (force till fracture and distance of deflect…

Combination of an allogenic and a xenogenic bone substitute material with injectable platelet-rich fibrin – A comparative in vitro study

The aim of the in vitro study was a comparison of an allogenic (ABSM) and a xenogenic bone substitute material (XBSM) with and without injectable platelet-rich fibrin (ABSM-i-PRF & XBSM-i-PRF) on cell characteristics of human osteoblasts (HOB). Here, ABSM and XBSM (+ i-PRF = test; - i-PRF = control) were incubated with HOB for 3, 7 and 10 days. HOB viability, migration, proliferation and differentiation (RT-PCR on alkaline phosphatase (AP), bone morphogenetic protein 2 (BMP-2) and osteonectin (OCN)) were measured and compared between groups. At day 3, an increased viability, migration and proliferation was seen for ABSM-i-PRF. For viability and proliferation (days 7 and 10) and for mig…

Diabetes and hyperglycemia as risk factors for postoperative outcome in maxillofacial surgery.

Abstract Background Aim of this study was to investigate the frequency of complications in maxillofacial surgery in-patients in correlation to diabetes mellitus or a pathologically altered glucose metabolism. Materials and methods All patients' electronic health records were analyzed retrospectively. Diabetes mellitus anamnesis, the treatment regime, blood glucose levels, and the duration of inpatient treatment were recorded. Glucose readings ≥200 mg/dL measured at any time and fasting glucose levels of ≥110 mg/dL were defined as hyperglycemic. Noted complications were infection, dehiscence, swelling, and necrosis. Results 8.7% out of 1374 patients had a known diabetes diagnosis. 13.0% had …

Diabetes Mellitus and Its Association to the Occurrence of Medication-Related Osteonecrosis of the Jaw

To date there is no consensus on the role of diabetes in the development of medication-related osteonecrosis of the jaws (MR-ONJ). Therefore, this study aimed to investigate the prevalence of diabetes and pathological glucose metabolism in patients with MR-ONJ compared to the general population. All maxillofacial surgery inpatients in one year at our department were investigated regarding diagnosis, anamnesis, medication, and blood glucose readings. 1374 records were analyzed. 35 patients with MR-ONJ were identified. Diabetics accounted for 14.3%. No significant difference in the prevalence of known diabetes was found, except for pathological glucose metabolism in patients with MR-ONJ (p &l…