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The aim of the present study was to analyze the osteogenic potential of a biphasic calcium composite material (BCC) with a negative surface charge for maxillary sinus floor augmentation. In a 61 year old patient, the BCC material was used in a bilateral sinus floor augmentation procedure. Six months postoperative, a bone sample was taken from the augmented regions before two titanium implants were inserted at each side. We analyzed bone neoformation by histology, bone density by computed tomography, and measured the activity of voltage-activated calcium currents of osteoblasts and surface charge effects. Control orthopantomograms were carried out five months after implant insertion. The BCC was biocompatible and replaced by new mineralized bone after being resorbed completely. The material demonstrated a negative surface charge (negative Zeta potential) which was found to be favorable for bone regeneration and osseointegration of dental implants.

Oxidised regenerated cellulose/collagen matrix (ORC/collagen matrix) modifies wound microenvironments by binding and inactivating excess levels of proteases such as elastase, plasmin and gelatinases in wound exudates. To compare levels of the gelatinases matrix metalloproteinase 2 (MMP-2), elastase and plasmin in wound exudates collected from chronic venous insufficiency patients with venous leg ulcers treated with either an ORC/collagen matrix or a standard control therapy. During a 12-week treatment period, wound exudate samples were obtained from a control group of 10 patients treated with a hydrocolloid dressing and a treatment group of 17 patients treated with a combination of ORC/collagen matrix and hydrocolloid dressing. On admission and days 5, 14 and every subsequent 14th day, ulcers were photographed to determine healing rate and changes in ulcer appearance, and MMP-2 concentration and the gelatinase, elastase and plasmin activities were analysed from wound exudates. The patients treated with ORC/collagen matrix showed a significant decrease in elastase, plasmin and gelastinase activity as compared with the control group, with no significant difference in the MMP-2 concentrations between the two groups. The results show a significant and immediate reduction in protease activity in wound exudates from venous leg ulcers treated with ORC/collagen.

Background The current surgical therapy of midfacial fractures involves internal fixation in which bone fragments are fixed in their anatomical positions with osteosynthesis plates and corresponding screws until bone healing is complete. This often causes new fractures to fragile bones while drilling pilot holes or trying to insert screws. The adhesive fixation of osteosynthesis plates using PMMA bone cement could offer a viable alternative for fixing the plates without screws. In order to achieve the adhesive bonding of bone cement to cortical bone in the viscerocranium, an amphiphilic bone bonding agent was created, analogous to the dentin bonding agents currently on the market. Methods The adhesive bonding strengths were measured using tension tests. For this, metal plates with 2.0 mm diameter screw holes were cemented with PMMA bone cement to cortical bovine bone samples from the femur diaphysis. The bone was conditioned with an amphiphilic bone bonding agent prior to cementing. The samples were stored for 1 to 42 days at 37 degrees C, either moist or completely submerged in an isotonic NaCl-solution, and then subjected to the tension tests. Results Without the bone bonding agent, the bonding strength was close to zero (0.2 MPa). Primary stability with bone bonding agent is considered to be at ca. 8 MPa. Moist storage over 42 days resulted in decreased adhesion forces of ca. 6 MPa. Wet storage resulted in relatively constant bonding strengths of ca. 8 MPa. Conclusion A new amphiphilic bone bonding agent was developed, which builds an optimizied interlayer between the hydrophilic bone surface and the hydrophobic PMMA bone cement and thus leads to adhesive bonding between them. Our in vitro investigations demonstrated the adhesive bonding of PMMA bone cement to cortical bone, which was also stable against hydrolysis. The newly developed adhesive fixing technique could be applied clinically when the fixation of osteosynthesis plates with screws is impossible. With the detected adhesion forces of ca. 6 to 8 MPa, it is assumed that the adhesive fixation system is able to secure bone fragments from the non-load bearing midfacial regions in their orthotopic positions until fracture consolidation is complete.

Esophageal cancer related gene 1 (ECRG1) is a novel candidate tumor suppressor gene in human esophageal squamous cells. Overexpression of ECRG1 protein inhibits tumor cell proliferation. Genetic polymorphisms in coding sequences of the gene may cause functional alterations of the gene product and be associated with higher cancer risk and disease phenotypes. A single nucleotide polymorphism (SNP) (Arg290Gln) found in the coding region of ECRG1 might play a role in susceptibility to esophageal squamous cell carcinoma. This study examined SNPs in ECRG1 in a similar tumor type (oral squamous cell carcinoma; OSCC) and investigated the relationship between SNPs in ECRG1 and the clinical outcome of patients with OSCC. DNA samples of 137 OSCC patients were analyzed for SNP genotypes Arg/Arg, Arg/Gln and Gln/Gln in the coding region (exon 8) of ECRG1. SNP genotypes Arg/Arg were found in 70 (51%), Arg/Gln in 60 (43%) and Gln/Gln in 7 (5%) patients. There was no significant association between genotypes and survival ( p =0.77) or relapse free survival ( p =0.32). The Gln/Gln genotype had the best survival (not significant) probably due to rare cases of SNP Gln/Gln genotype. Genotype Arg/Arg might be a potential negative prognostic marker in OSCC, but more studies with higher patient numbers are required.

The range of bone regeneration materials suitable for maxillar bone augmentation has increased steadily in the past few years and there is now a wide variety of materials being used. In the present case report, we analyzed the state of bone regeneration after sinus floor augmentation using a nanocrystalline in-phase synthetic anorganic hydroxyapatite bone grafting material (Ostim). A 60-year-old female patient underwent maxillary sinus floor elevation and the cavity was filled with Ostim three years before. Actually, she presented herself with loosening of the dental implant at position 17, as a result of parafunction. At the time of the insertion of a second implant at position 17, bone samples were taken by using a trepan drilling device from the previously augmented area. These samples were analyzed histologically to determine the extent of bone remodeling around the deposits of Ostim. We found that the Ostim deposits were surrounded largely by woven bone and, in parts, by lamellar bone and had facilitated osteoconductive bone regeneration. The adjacent implant, at position 16, which beared a crown exposed to proper biting forces without parafunction, showed proper clinical and radiological characteristics of complete and firm integration into the area which was also filled with Ostim three years ago. We conclude that the use of the nanocrystalline hydroxyapatite Ostim with its stable volume properties appears to be suitable for maxillary sinus floor augmentation. Furthermore, we even found osteoconductive bone regeneration under Ostim near the site of the loosened implant.

Purpose In the treatment of midface fractures, the fragments are immobilized using screws and plates for osteosynthesis until reunion has occurred. This method involves drilling holes for the insertion of the screws, which can be associated with additional fracturing of the corresponding bone owing to the complex architecture and thin layers of facial bone. To alleviate this problem, new adhesive techniques for fixing the plates for osteosynthesis have been investigated, mitigating the detrimental effects of screw hole drilling. In the present experimental study, the strength of this adhesive bond and its resistance to hydrolysis were investigated. Materials and Methods To determine the adhesive bonding strength, a tension test was implemented. Osteosynthesis plates with screw holes 1.3 mm in diameter were fixed to cortical bone samples of bovine femur using ultraviolet (UV) light-curing polymethylmethacrylate bone cement. To facilitate bonding, the surface of the bone was conditioned with an amphiphilic bonding agent before cementing. UV light curing was implemented using either a conventional UV unit, such as is used in dentistry, or with a specialized UV unit with a limited emission spectrum but high luminosity. Reference control samples were prepared without application of the bone bonding agent. After this procedure, the samples were stored for 1 to 7 days at 37°C submerged in 0.9% saline solution before being subjected to the tension test. Results Without the bone bonding agent, the bonding strength was 0.2 MPa. The primary average bonding strength at day 0 was 8.5 MPa when cured with the conventional UV unit and 14 MPa for the samples cured with the specialized UV unit. An almost constant average bond strength of 8 and 16 MPa was noted for all samples stored up to 7 days after curing with the conventional and specialized UV unit, respectively. Conclusion With the development of a new bone bonding agent, a method is now available to promote the bonding between the hydrophilic bone surface and the hydrophobic polymethylmethacrylate bone cement by creating an interlayer that is beneficial for adhesion. In the present in vitro study, the strength of this bond and its resistance to hydrolysis were investigated. This new method could have clinical bearing in cases in which conventional fixation with screws and plates is limited, such as can occur in comminuted fractures. The observed average bonding strengths of 8 to 16 MPa support the implementation of this technique in nonload-bearing regions such as the midface, facilitating immobilization until the bone reunion is complete.

Aim: Multiple studies have reported associations between periodontitis and particular human leukocyte antigens (HLA). Because associations are inconsistent, we conducted a systematic literature review and a meta-analysis focusing on Caucasian case–control studies. Material and Methods: A literature search reporting on the distribution of HLA class I and II phenotypes in Caucasian patients with chronic periodontitis (CP) and aggressive periodontitis (AP) was performed. Data sources included electronic databases and bibliographies of published articles. Screening and data abstraction were conducted independently by different reviewers. Results: Out of 174 publications, 12 studies were considered to be suitable for metaanalysis. In patients with CP, no significant HLA associations were found. Patients with AP showed a positive association with HLA-A9 [odds ratio 5 2.59 (95% confidence interval 1.36–4.83), p 5 0.004] and HLA-B15 [1.90 (1.15–3.16), p 5 0.01] as well as a negative association with HLA-A2 [0.72 (0.56–0.94), p 5 0.01] and -B5 [0.49 (0.30–0.79), p 5 0.004]. On grouping all patients into one periodontitis group (AP1CP), the same deviations were confirmed with higher statistical significance. For HLA-A9 and -B15, significant heterogeneity was found between the studies. No significant associations were found with HLA class II antigens. Conclusions: HLA-A9 and -B15 seem to represent susceptibility factors for AP whereas HLA-A2 and -B5 are potential protective factors against periodontitis among Caucasians.

Osteosarcoma of the jaw (JOS) constituting 5% to 13% of all osteosarcoma is a locally aggressive malignant mesenchymal tumor with high tendency to local recurrence and the ability to produce tumor osteoid. Compared to osteosarcoma of the remaining skeleton (SOS) JOS metastasizes relatively rarely and relatively late. It differs significantly from SOS in its biological behaviour.The presented case deals with a 60-year-old male patient suffering from a newly occurred polypous mucosal tumor of the right-sided maxillary alveolar ridge bioptically diagnosed as a granulation tissue polyp first. After transmaxillary resection of the tumor and consultation of a bone tumor reference center the final diagnosis of a high-grade chondroblastic osteosarcoma could be made. The recommended radical resection of the tumor was declined by the patient because of the expected cosmetic consequences. After surgical reduction of the rapidly growing sarcoma chemotherapy according to the COOS/EURO-B.O.S.S. protocol was initiated at a stage when computed tomography showed diffuse metastatic disease to the lungs. Chemotherapy could delay the progress of the disease only temporarily. The patient died from respiratory insufficiency.In JOS radical surgical resection is the therapy of first choice. For substantiation of the diagnosis and central registration of the cases a bone tumor reference center should be contacted.

Recent studies indicated the benefit of hydrocortisone in septic patients based on the significant reduction of catecholamines and improved outcome in common intensive care patients. The treatment of intensive care burn patients with corticosteroids was discussed with great caution due to the especially compromised immune status of severely burned patients. The purpose of this study was to investigate the influence of corticosteroids in burn patients during septic shock. In our burn unit, we started with the administration of cortisol in 2001. In this retrospective study, 10 severely burned patients received, ≥24 h after norepinephrine dependency, hydrocortisone infusions of 200 mg/24 h. The course of norepinephrine dose, hemodynamic measurements (Swan–Ganz–Catheter) and daily Sequential Organ Failure Assessment (SOFA-Score) were analyzed and compared to nine (catecholamine-dependent) burn patients without cortisol therapy. Statistical analysis by means of Fisher's Exact Test revealed beneficial effects (morbidity and mortality) of low dose cortisol therapy compared to control patients. However, the results of this study must be interpreted with caution because of its limited number of patients and its retrospective character. Further randomized prospective controlled studies are necessary to determine the efficacy and safety of cortisol therapy in burn patients.

BACKGROUND New evidence suggests that matrix metalloproteinases (MMPs) may facilitate angiogenesis as well as function to generate angiogenesis inhibitors. In this study, the angiogenic effect of wound exudates from patients with venous insufficiency ulcers was examined in an in vitro angiogenesis model with and without synthetic MMP-2/-9 inhibitor. METHODS Wound exudates were obtained from 20 patients with venous insufficiency ulcers and 20 control patients with donor-site wounds after skin grafting for burns. In the angiogenesis model, suramin (20 microg/ml) was used in five wells without wound fluid as negative control, and vascular endothelial growth factor (1 microg/ml) was used in five other wells as positive control. Chronic wound fluids were analyzed without and with a synthetic MMP-2/-9 inhibitor with a concentration of 2 microM and 20 microM in the medium. The total length of tubules was calculated by map reader. Statistical analysis was performed using the Mann-Whitney test. The level of significance was considered to be p < 0.05. RESULTS Chronic ulcer exudates inhibited angiogenesis significantly (490 +/- 130 microm) compared with acute wound fluids (1740 +/- 320 microm; p < 0.05). In wells with chronic wound exudates and high concentrations of MMP-2/-9 inhibitor, angiogenesis was stimulated significantly (870 +/- 220 microm, p < 0.05). CONCLUSIONS In this model, reduced angiogenesis might be due to an antiangiogenic effect of MMP-2 and MMP-9. MMP-2/-9 inhibition results in a stimulation of angiogenesis and might be an approach for the treatment of patients with chronic wounds and reduced angiogenesis.

Head & face medicine 10, 34 (2014). doi:10.1186/1746-160X-10-34, Published by BioMed Central, London

Head & face medicine 6, 12 (2010). doi:10.1186/1746-160X-6-12, Published by BioMed Central, London

Background Different types of bioabsorbable and nonresorbable membranes have been widely used for guided tissue regeneration (GTR) with its ultimate goal of regenerating lost periodontal structures. The purpose of the present study was to evaluate the biological effects of various bioabsorbable and nonresorbable membranes in cultures of primary human gingival fibroblasts (HGF), periodontal ligament fibroblasts (PDLF) and human osteoblast-like (HOB) cells in vitro. Methods Three commercially available collagen membranes [TutoDent® (TD), Resodont® (RD) and BioGide® (BG)] as well as three nonresorbable polytetrafluoroethylene (PTFE) membranes [ACE (AC), Cytoplast® (CT) and TefGen-FD® (TG)] were tested. Cells plated on culture dishes (CD) served as positive controls. The effect of the barrier membranes on HGF, PDLF as well as HOB cells was assessed by the Alamar Blue fluorometric proliferation assay after 1, 2.5, 4, 24 and 48 h time periods. The structural and morphological properties of the membranes were evaluated by scanning electron microscopy (SEM). Results The results showed that of the six barriers tested, TD and RD demonstrated the highest rate of HGF proliferation at both earlier (1 h) and later (48 h) time periods (P < 0.001) compared to all other tested barriers and CD. Similarly, TD, RD and BG had significantly higher numbers of cells at all time periods when compared with the positive control in PDLF culture (P ≤ 0.001). In HOB cell culture, the highest rate of cell proliferation was also calculated for TD at all time periods (P < 0.001). SEM observations demonstrated a microporous structure of all collagen membranes, with a compact top surface and a porous bottom surface, whereas the nonresorbable PTFE membranes demonstrated a homogenous structure with a symmetric dense skin layer. Conclusion Results from the present study suggested that GTR membrane materials, per se, may influence cell proliferation in the process of periodontal tissue/bone regeneration. Among the six membranes examined, the bioabsorbable membranes demonstrated to be more suitable to stimulate cellular proliferation compared to nonresorbable PTFE membranes.

Purpose Significant vasovagal reaction is one of the untoward events in the course of simple extractions. The present study then aimed to record the patients’ heart rate during the extraction procedure. Materials and methods Informed consents were obtained in advance. Patients were placed in the dental chair and their heart rate was measured before /and prior to the anesthetic injection, during, and after dental extraction on a pulse oxymeter device. Data were analyzed using paired t-test. Results Sixty one patients were included. The mean heart rates of these patients prior, during, and after extraction were 88, 86 and 81, respectively. Two by two comparisons showed a significant decrease in the mean heart rate during extraction compared to the baseline and also after extraction compared to both before and during extraction (p Conclusions Despite the presence of sufficient local anesthesia and performing the extraction with the least trauma, a significant decrease in heart rate is evident.

A 66-year-old female patient was admitted to our department with a large tumor of the tongue measuring 10 cm in diameter. The tumor occupied nearly the entire oral cavity and showed exophytic and ulcerative areas. Histological analysis revealed a low grade squamous cell carcinoma (SCC) of the tongue. Bilateral enlarged cervical lymphatic masses were also present. The extent of the tumor infiltration was assessed by fluoro-2-deoxy-glucose-positron emission tomography (PET) scans showing an elevated activity of the tracer corresponding to the assumed cervical metastases. Additionally, pulmonary metastases were identified. Contrast enhanced computed tomography (CT) scans showed metastases in the soft tissues of the abdomen, legs and arms. Foci of distant metastases were found in the left upper anterior thoracal wall, near the intraabdominal portion of the aorta, near the right iliac crest and in both the right vastus medialis- and adductor magnus muscles. The final diagnosis was a T4N3M1(G3)(C3) SCC of the tongue with multiple distant thoracal, abdominal and intramuscular metastases. The survival expectancy was five weeks, and the patient finally deceased by cardiopulmonary complications.