bluuebunny/crossref_metadata_2025_split huggingface dataset:
Randomized controlled clinical trial of customized zirconia and titanium implant abutments for canine and posterior single‐tooth implant reconstructions: preliminary results at 1 year of function
Authors: Sailer Irena , Zembic Anja , Jung Ronald Ernst , Siegenthaler David , Holderegger Claudia , Hämmerle Christoph Hans Franz 
Published: February 2009

AbstractObjectives: The aim of this study was to test whether or not customized zirconia abutments exhibit the same survival rates in canine and posterior regions as titanium abutments, and to compare the esthetic result of the two abutment types.Material and methods: Twenty‐two patients with 40 implants in posterior regions were included and the implant sites were randomly assigned to 20 customized zirconia and 20 customized titanium abutments. All‐ceramic (AC) and metal–ceramic (MC) crowns were fabricated. In all except two cases, the crowns were cemented on the abutments using resin or glass‐ionomer cements. Two zirconia reconstructions were screw retained. At baseline, 6 and 12 months, the reconstructions were examined for technical and biological problems. Probing pocket depth (PPD), plaque (Pl) and bleeding on probing (BOP) were assessed and compared with natural control teeth. Furthermore, the difference of color (ΔE) of the peri‐implant mucosa and the gingiva of control teeth was evaluated by means of a spectrophotometer (Spectroshade). The data were analyzed with Student's unpaired t‐test, ANOVA and regression analyses.Results: Twenty patients with 19 zirconia and 12 titanium abutments were examined at a mean follow‐up of 12.6±2.7 months. The survival rate for reconstructions and abutments was 100%. No technical or biological problems were found at the test and control sites. Two chippings (16.7%) occurred at crowns supported by titanium abutments. No difference was found regarding PPD (meanPPDZrO2 3.4±0.7 mm, mPPDTi 3.3±0.6 mm), Pl (mPlZrO2 0.2±0.3, mPlTi 0.1±1.8) and BOP (mBOPZrO2 60±30%, mBOPTi 30±40%) between the two groups. Both crowns on zirconia and titanium abutments induced a similar amount of discoloration of the soft tissue compared with the gingiva at natural teeth (ΔEZrO2 8.1±3.9, ΔETi 7.8±4.3).Conclusions: At 1 year, zirconia abutments exhibited the same survival and a similar esthetic outcome as titanium abutments.
A study of the bone healing kinetics of plateau versus screw root design titanium dental implants
Authors: Leonard Gary , Coelho Paulo , Polyzois Ioannis , Stassen Leo , Claffey Noel 
Published: February 2009

AbstractObjective: This study was designed to compare the bone healing process around plateau root from (PRF) and screw root from (SRF) titanium dental implants over the immediate 12 week healing period post implant placement.Material and methods: 32PRF and 32SRF implants were placed in 8 beagle dogs at 12, 8, 5 and 3 weeks prior to enthanisation using a bilaterally balanced distribution. Undecalcified ground sections were prepared from the biopsies taken and histometric measurements of bone implant contact (BIC) and bone area fraction occupancy (BAFO) were made on the middle 5 mm portion of each 8 mm implant root length.Results: The analysis showed that although measurements of bone to implant contact (BIC) and bone area fraction occupancy (BAFO) tended to be greater for the SRF implants at all four time points, the differences in measurements between implant types did not reach statistical significance (P=0.07, P=0.06). The effect of time on BIC and BAFO was found to be strongly significant for both implant types thus indicating a statistically significant increase in BIC and BAFO overall with time (P=0.004, P=0.002). Furthermore, both PRF and SRF implants behaved similarly over time with measurements of BIC and BAFO progressing in parallel. Histomorphologic analysis of these sections demonstrated the prominent role of woven bone (callus) in the bone healing process around PRF implants.Conclusion: The results can be interpreted to indicate a comparable development of secondary stability for both PRF and SRF implant designs. However, as these parameters reflect the structural connection between implant and bone and not the functional properties of the bone to implant interface, they cannot be regarded as comprehensive measures of osseointegration. This particularly relevant given the reduced load bearing capacity of woven bone.
Effects of irrigation temperature on heat control in vitro at different drilling depths
Authors: Sener Bedrettin Cem , Dergin Guhan , Gursoy Bahar , Kelesoglu Ergun , Slih Imad 
Published: February 2009

AbstractPurpose: Thermal injury during implant bed preparation has a major influence on implant osseointegration and survival. This study investigated the effectiveness of the temperature of the saline solution used for heat control during drilling.Material and methods: Fresh frozen edentulous segments of bovine mandibles were sectioned into 12 × 6 cm pieces. Thermoresistors were placed 0.5 mm from the drilling cavity walls, at depths of 3, 7, and 12 mm. Signals from the three thermoresistors were analyzed using ORIGIN 5.0 software.Results: The maximum temperatures during drilling without irrigation were 50.9, 47.4, and 38.1°C at depths of 3, 7, and 12 mm, respectively. With irrigation using saline at 25 and 10°C, the maximum temperatures at a depth of 12 mm were 37.4 and 36.3°C, respectively. All other measurements with both 25 and 10°C saline were below body temperature.Discussion and conclusion: This experimental in vitro study showed that more heat was generated in the superficial part of the drilling cavity than at the bottom. Therefore, external irrigation at room temperature can provide sufficient cooling during drilling. Lower temperature saline was more effective in cooling the bone, and irrigation of the site should be continued between the drilling steps.
Surface microgrooves and acid etching on titanium substrata alter various cell behaviors of cultured human gingival fibroblasts
Authors: Kim Su‐Yeon , Oh Namsik , Lee Myung‐Hyun , Kim Sung‐Eun , Leesungbok Richard , Lee Suk‐Won 
Published: February 2009

AbstractObjective:This study aimed to investigate the influence of surface microgrooves and acid etching on titanium substrata on cell proliferation and gene expression of cultured human gingival fibroblasts.Material and methods:Ti substrata with various dimensions of microgrooves and further acid etching comprised four experimental groups (E15/3.5, E30/5, E60/10, and E90/15), whereas smooth and acid etched Ti discs were both used as control (NE0 and E0). The chemical composition of the control and experimental cp Ti substrata was analyzed by X‐ray photoelectron spectroscopy (XPS). Cell proliferation, gene expression, and protein expression of cultured human gingival fibroblasts were analyzed between all groups using bromodeoxyuridine (BrdU) assay, reverse‐transcriptase polymerase chain reaction (RT‐PCR), and Western blotting, respectively.Results:The XPS results showed that the Ti substrata used in this study showed no significant differences in the expression of surface chemical composition. BrdU assay showed that cell proliferation was significantly increased in E60/10 compared with that in any other group. In RT‐PCR, E60/10 was noted to increase the expression of various genes involved in cell‐matrix adhesion and adhesion‐dependent cell cycle progression. In Western blotting, increased expression of fibronectin and Rho A was noted in E60/10 compared with that in NE0 or E15/3.5.Conclusion:This study indicates that surface microgrooves 60 μm in width and 10 μm in depth, and further acid etching on Ti substrata trigger the proliferation and alter the expression of both genes and proteins in cultured human gingival fibroblasts.
Oxidised low‐density lipoprotein and arterial function in β‐thalassemia major
Authors: Stakos Dimitrios A. , Tavridou Anna , Margaritis Dimitrios , Tziakas Dimitrios N. , Kotsianidis Ioannis , Chalikias George K. , Tsatalas Kostantinos , Bourikas George , Manolopoulos Vangelis G. , Boudoulas Harisios 
Published: February 2009

AbstractObjectives:  Vascular abnormalities such as endothelial dysfunction and arterial stiffness have been described in patients with β‐thalassemia major (β‐TM). Increased concentrations of oxidised low‐density lipoprotein cholesterol (oxLDL) have been observed in those patients, but possible associations between oxLDL and arterial function in β‐TM have not been defined.Methods:  Twenty‐six patients (11 males) with β‐TM (age 23 ± 4 yr) and 30 age and gender‐matched healthy subjects were studied. Aortic stiffness was assessed by carotid‐femoral pulse wave velocity (PWVc‐f) using applanation tonometry; brachio‐radial artery stiffness was assessed by carotid‐radial PWV (PWVc‐r). Flow‐mediated dilatation (FMD) of the brachial artery and oxLDL (ELISA) were also measured.Results:  Patients with β‐TM had higher oxLDL levels (68.6 ± 13.7 mU/mg vs. 50.0 ± 12.6 mU/mg, P = 0.005), decreased FMD (3.6 ± 2.5% vs. 7.3 ± 3.5%, P = 0.001) and higher PWVc‐f compared with controls (8.4 ± 1.7 vs. 7.2 ± 1.1. P < 0.002). FMD of the brachial artery was negatively associated with OxLDL concentrations in simple linear (r2 = −0.25, P = 0.001) and multiple linear regression analysis (β = −0.242, P = 0.03, R2 = 0.43, P = 0.0002). PWVc‐r was positively associated with OxLDL (r2 = 0.23, P = 0.003) and showed a tendency in multiple regression analysis (β = 0.18, P = 0.05). PWVc‐r and FMD were also significantly correlated (β = −0.213, P = 0.04) in β‐TM patients. There was no association between oxLDL and PWVc‐f.Conclusion:  An association between oxLDL, arterial elastic properties and endothelial dysfunction of muscular arteries was found. OxLDL may represent a contributing factor for the vascular manifestations described in β‐TM patients.
Is the early cyclosporine A level predictive of the outcome of immunosuppressive therapy in severe aplastic anemia?
Authors: Song Moo‐Kon , Chung Joo‐Seop , Joo Young‐Don , Kim Yang‐Soo , Kim Sung‐Hyun , Seol Young‐Mi , Shin Ho‐Jin , Choi Young‐Jin , Cho Goon‐Jae 
Published: February 2009

AbstractImmunosuppressive therapy (IST) has provided an alternative treatment option for cure of aplastic anemia patients who cannot receive bone marrow transplantation. Although there have been many recent studies on the efficacy of antithymoglobulin (ATG) combined with cyclosporine A (CsA), there is no data on the correlation between the variability of CsA levels and the response to IST. Therefore, we retrospectively assessed the factors associated with IST efficacy in patients with acquired severe aplastic anemia (SAA). Sixty‐six patients were treated with ATG combined with CsA for 6 months. In the response group, the CsA levels were increased rapidly to more than 200 ng/mL within the first 2 wk after starting the IST. However, the non‐response group had a pattern of slower increase of the CsA levels. The CsA levels, during the first and second week of treatment with IST, were significantly different in the responders and non‐responders. The factors predictive of response to IST and survival were analyzed. The univariate analysis showed that a younger age at the initiation of IST, a high absolute neutrophil count prior to starting IST, a short interval between the diagnosis and initiation of IST, and high CsA levels during the first and second week of IST treatment were positively associated with the response rate and overall survival. The multivariate analysis showed that these four factors were independent factors associated with a longer patient survival. A high response rate was associated with a short interval between diagnosis and initiation of IST as well as high CsA levels during the first and second week of IST. Therefore, early intensification of CsA levels might improve patient outcome.
Neutrophils in chronic and aggressive periodontitis in interaction with Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans
Authors: Guentsch A. , Puklo M. , Preshaw P. M. , Glockmann E. , Pfister W. , Potempa J. , Eick S. 
Published: February 2009

Background and Objective:  This study analyzed the interaction of Porphyromonas gingivalis ATCC 33277 and Aggregatibacter actinomycetemcomitans Y4 with peripheral blood polymorphonuclear neutrophils taken from patients with aggressive periodontitis and chronic periodontitis.Material and Methods:  Peripheral blood polymorphonuclear neutrophils obtained from 12 patients with chronic periodontitis, six patients with aggressive periodontitis and 12 healthy controls were exposed to P. gingivalis and A. actinomycetemcomitans following opsonization of the bacteria using the patient’s own serum. Serum immunoglobulin G (IgG) levels against both periodontopathogens were measured. Phagocytosis and killing of the bacteria, as well as the extracellular human neutrophil elastase activity, were quantified. The total amount and the extracellular release of reactive oxygen species were measured using luminol‐dependent and isoluminol‐dependent chemiluminescence.Results:  Polymorphonuclear neutrophils from patients with chronic (62.16 ± 19.39%) and aggressive (43.26 ± 26.63%) periodontitis phagocytosed more P. gingivalis than the healthy controls (24.43 ± 19.87%) at the 30‐min time point after exposure to the bacteria (p < 0.05). High serum IgG levels against P. gingivalis and A. actinomycetemcomitans were detected in subjects with periodontitis. Polymorphonuclear neutrophils from subjects with chronic and aggressive periodontitis released significantly more reactive oxygen species and demonstrated greater human neutrophil elastase activity in the absence of any stimulus than polymorphonuclear neutrophils from healthy controls (p < 0.05). Polymorphonuclear neutrophils in chronic periodontitis released significantly more reactive oxygen species when exposed to P. gingivalis and A. actinomycetemcomitans than polymorphonuclear neutrophils in aggressive periodontitis.Conclusion:  High serum IgG levels against P. gingivalis and A. actinomycetemcomitans promote phagocytosis in periodontitis. The extracellular release of reactive oxygen species and neutrophil elastase by polymorphonuclear neutrophils may also contribute to damage of the surrounding periodontal tissues.
Cyclooxygenase‐2‐derived prostaglandin E2 is involved in vascular endothelial growth factor production in interleukin‐1α‐stimulated human periodontal ligament cells
Authors: Bando Y. , Noguchi K. , Kobayashi H. , Yoshida N. , Ishikawa I. , Izumi Y. 
Published: February 2009

Background and Objective:  Prostaglandin E2, which exerts its actions via EP receptors (EP1, EP2, EP3 and EP4), is a bioactive metabolite of arachidonic acid produced by cyclooxygenase‐1 and/or cyclooxygenase‐2. Interleukin‐1α induces prostaglandin E2 production via cyclooxygenase‐2 in human periodontal ligament cells. Vascular endothelial growth factor is a key regulator of physiologic as well as pathologic angiogenesis and has been indicated to be involved in the pathology of periodontal diseases. In the present study, we investigated whether interleukin‐1α induced vascular endothelial growth factor production in human periodontal ligament cells and whether cyclooxygenase‐2‐derived prostaglandin E2 regulated interleukin‐1α‐induced vascular endothelial growth factor production.Material and Methods:  Human periodontal ligament cells were obtained from extracted teeth of periodontally healthy subjects. After pre‐incubation with a nonselective cyclooxygenase‐1/2 inhibitor, indomethacin or a selective cyclooxygenase‐2 inhibitor (NS‐398), periodontal ligament cells were treated with or without interleukin‐1α, prostaglandin E2, various EP receptor agonists and dibutyryl cAMP (a cAMP analogue). The levels of vascular endothelial growth factor and prostaglandin E2 in the culture supernatant were measured by enzyme‐linked immunosorbent assay. The vascular endothelial growth factor mRNA expression was evaluated by semiquantitative reverse transcription–polymerase chain reaction.Results:  Interleukin‐1α induced vascular endothelial growth factor production in a dose‐dependent and time‐dependent manner. The interleukin‐1α‐induced vascular endothelial growth factor mRNA and protein expression was inhibited to the same extent by indomethacin and NS‐398. Indomethacin and NS‐398 completely inhibited interleukin‐1α‐induced prostaglandin E2 production. Exogenous prostaglandin E2, butaprost (an EP2 receptor agonist) and dibutyryl cAMP abolished the inhibitory effect of indomethacin on interleukin‐1α‐induced vascular endothelial growth factor production.Conclusion:  We suggest that interleukin‐1α induced vascular endothelial growth factor production via cyclooxygenase‐2‐derived prostaglandin E2 in human periodontal ligament cells. The interleukin‐1α/prostaglandin E2 pathway might regulate vascular endothelial growth factor production in periodontal lesions.
Periodontitis‐induced lipid peroxidation in rat descending aorta is involved in the initiation of atherosclerosis
Authors: Ekuni D. , Tomofuji T. , Sanbe T. , Irie K. , Azuma T. , Maruyama T. , Tamaki N. , Murakami J. , Kokeguchi S. , Yamamoto T. 
Published: February 2009

Background and Objective:  Periodontitis is a risk factor for the development of atherosclerosis. Recent studies indicate that oxidative mechanisms, including lipid peroxidation, are involved not only in periodontitis but also in atherosclerosis. Lipid peroxidation may play an important role in the pathogenesis of atherosclerosis, particularly during its earliest stages. The purpose of this study was to investigate the relationship between lipid peroxidation induced by periodontitis and the initiation of atherosclerosis.Material and Methods:  Sixteen rats were randomly divided into two groups of eight rats each. Periodontitis was ligature‐induced for 4 wk in the experimental group, whereas the control group was left untreated. After the experimental period, the mandibular first molar regions were resected and then subjected to histological analysis and measurement of hexanoyl‐lysine expression as an indicator of lipid peroxidation. Descending aorta was used for measuring the levels of hexanoyl‐lysine, reactive oxygen species and lipid deposits, and for real‐time polymerase chain reaction microarray analysis. The level of hexanoyl‐lysine was also measured in serum.Results:  In the experimental group, the levels of hexanoyl‐lysine in periodontal tissue and serum increased. Only aorta samples in the experimental group showed lipid accumulation, with increased expression of hexanoyl‐lysine, reactive oxygen species and oxidative stress‐related genes (including nitric oxide synthases 2 and 3), whereas the superoxide dismutase 1 gene level was down‐regulated.Conclusion:  In a ligature‐induced periodontitis rat model, increased lipid peroxidation was found in serum and aorta as well as in periodontal tissue. Atherosclerosis‐related gene expression and histological changes were also stimulated. Periodontitis‐induced lipid peroxidation in the aorta may be involved in the early stage of atherosclerosis.
Randomised controlled trial of the efficacy of HybenX in the symptomatic treatment of recurrent aphthous stomatitis
Authors: Porter SR , Al‐Johani K , Fedele S , Moles DR 
Published: February 2009

Background:  The treatment of recurrent aphthous stomatitis (RAS) is principally directed towards reducing the pain and duration of each episode of ulceration; however, there remain few agents for which there is definitive evidence of benefit.Aims:  The aims of the present study were to determine the efficacy of HybenX (Epien Medical Inc., Minneapolis, MN, USA), vs another device used for the treatment of RAS (Salicept; Carrington Laboratories Inc., lrving, TX, USA) to reduce the symptoms and duration of RAS and determine the safety of HybenX for this clinical application.Material and methods:  Sixty‐three individuals (36 male, 27 female, group median age 25years, range 17.8–57.9years) were entered into a prospective randomised controlled trial of HybenX vs an occlusive covering device (Salicept oral patches; Carrington Laboratories).Results:  Painful symptoms over a 5‐day posttreatment period were reduced by both agents although HybenX was statistically more effective at day 2 than Salicept, and there was a trend for HybenX to cause greater pain reduction than Salicept over this 5‐day period. Both agents gave rise to few adverse side effects – a total of nine adverse events in eight patients were recorded. All were unlikely to be related to the treatment devices. HybenX was only applied on one occasion to the HybenX group, while individuals in the Salicept group were able to self medicate as required. The mean number of Salicept patches used per day per subject was three (s.d. 3.3) on day 1 posttreatment, 3.4 (s.d. 3.1) on day 2 and 2.7 (s.d. 1.9) on day 3. Thereafter, the number of applications fell to a mean of 0.8 on day 7.Conclusion:  It is concluded that HybenX safely and effectively reduces the painful symptoms of RAS.
The influence of hydrological regime and grazing management on the plant communities of a karst wetland (Skealoghan turlough) in Ireland
Authors: Moran J. , Sheehy Skeffington M. , Gormally M. 
Published: February 2009

AbstractQuestion:What is the influence of hydrological regime, soils and management on the plant community composition and species richness of Skealoghan turlough (groundwater dependent calcareous wetland).Location:Skealoghan turlough, County Mayo, Ireland.Methods:Percentage cover of vascular plants and bryophytes were recorded, and data on hydrological regimes, soils and management were collected. Data were analysed using multivariate statistical techniques.Results:A total of 69 species of vascular plants and mosses were recorded. Cluster analysis grouped the samples into two separate communities, theCirsio‐Molinietumand theRanunculo‐Potentilletum anserinaeplant communities. The plant community composition and species richness followed a main gradient down into the turlough basin, but also varied with microtopography, resulting in a mosaic of vegetation types.Conclusions:The biodiversity and conservation value of the site is linked to the heterogeneity in its physical environment in which hydrology, soils and grazing management all play critical roles.
The use of GIS techniques to quantify the hydrological regime of a karst wetland (Skealoghan turlough) in Ireland
Authors: Moran J. , Kelly S. , Sheehy Skeffington M. , Gormally M. 
Published: February 2009

AbstractQuestion: Can GIS and GPS technology be used to quantify the hydrological regime of different plant communities on turloughs (groundwater dependent calcareous wetlands)?Location: Skealoghan turlough, County Mayo, Ireland.Methods: Plant communities were mapped and digitised with GIS software and a digital elevation model of the site was constructed from differential GPS data. Together with records of water level fluctuations on the site from May 2001 to May 2004, these data were used to calculate hydrological variables for each plant community. Hierarchical cluster analysis was used to identify groups of plant communities with similar hydrological regimes.Results: 15 plant communities were mapped at Skea loghan, with the Cirsio‐Molinietum and Ranunculo‐Potentilletum anserinae being the dominant phytosociological associations. Skealoghan is subject to large temporal and spatial variation in its hydrological regime and fluctuations in water level are intrinsically linked to rainfall. The spatial variation in flooding can be linked to the vegetation zones.Conclusions: GIS and DGPS technology can be used to quantify the hydrological regime of different plant communities on turloughs. Since the hydrological regime is a major environmental factor controlling the vegetation composition of the site, the maintenance of natural flooding regimes is a vital component for the conservation and management of the diverse vegetation mosaic at Skealoghan turlough.