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Background Assessment of intracardiac flows and turbulence has acquired rising significance in the past few years, due to the development and introduction of technologies for non-invasive cardiovascular imaging. Recent studies have shown that alterations in intracardiac fluid dynamics can be helpful to identify abnormalities in cardiac function. Purpose This study investigates the additional information provided by the quantitative assessment of intracardiac flow dynamics for the evaluation of patients with aortic stenosis (AS), by using an advanced echocardiography vortex-based approach. Methods Sixty-one patients with severe AS (33 females) and 38 healthy sex- and BSA-matched controls (CTRL) (15 females) were prospectively included and underwent echocardiographic assessment of intracardiac flow dynamics. Echocardiographic measurements were performed on apical three chamber views. The HyperDoppler software adapted to the echo-scanner without contrast injection was used to assess intracardiac vortex properties. The following parameters were obtained: vortex area (VA) (the ratio between the total vortex area and the left ventricular (LV) area); vortex length (VL) (the longitudinal length of the vortex relative to the total LV length; vortex depth (VD) (the distance of the vortex center from the LV base relative to the total LV long axis). Inter-rater variability was measured using intraclass correlation coefficients (ICCs) between two independent operators. Results Patients with severe AS (mean gradient: 47,5±13,9 mmHg; aortic valve area: 0.7±0.2 cm2; ejection fraction: 53±7%) had increased LV wall thickness (p0.001, respectively) were significantly higher in AS patients compared with CTRL. Among those who underwent TAVR, we observed a significant difference in the delta values of VA and VL pre-postTAVR in patients with and without significant paravalvular leak (p Conclusions The newly defined VA, VL and VD, quantitative indices of vortical flow, were significantly increased in the LV cavity of patients with severe AS compared to normal subjects. These indices, whose measurement was feasible and reliable, might provide complementary information to standard echocardiography, useful for the further diagnostic and prognostic characterization of the heterogeneous population of patients with severe AS. Funding Acknowledgement Type of funding sources: None.

Background Over the last decades growing evidence have demonstrated the promising role of intracardiac flow dynamic analysis in evaluating cardiac performance. Diastolic forces contribute to the formation of vortices, complex structures capable of kinetic energy storage and responsible of a smoother transition of blood from left ventricular (LV) inlet to outlet. Change in shape and location of these structures has been related with cardiovascular disease and prognosis. Purpose To investigate quantitative changes in vortices parameters in patients with different ventricular geometry. Methods We enrolled 72 consecutive patients (age 66±11 years, 49 male, 68%) with LV concentric hypertrophy (CH, n=15), eccentric hypertrophy (EH, n=13), concentric remodeling (CR, n=15) and normal LV geometry (CTRL, n=29). Each patient underwent a complete echocardiographic examination and a non-invasive intracardiac fluid dynamic analysis by Color Vector Flow Mapping. A 3-chamber apical view with a frame rate between 22 and 25 Hz has been acquired and subsequently analyzed offline by a semi-automatic software obtaining the following parameters: vortex area (VA) (the ratio between the total vortex area and the left ventricular (LV) area); vortex length (VL) (the longitudinal length of the vortex relative to the total LV length; vortex depth (VD) (the distance of the vortex center from the LV base relative to the total LV long axis). Bland Altman Plot has been used to assess intra and inter-observer variability. Results Mean VD was higher in CR, CH and EH compared to CTRL (p=0.013, p=0.001 and p=0.022, respectively). Moreover, CH showed higher VL (p=0.006) and larger VA (p=0.012) compared to CTRL. A similar trend was noticed in EH patients, despite did not reach statistical significance (p=0.21 and p=0.07 for VA and VL respectively). No significative differences in vortices parameters have been observed between CH and EH. Conclusion(s) This is the first study providing quantitative echocardiographic parameters of vortex location and morphology in different LV geometries. Higher values of VD were found in CR, CH and EG. Quantitative intra dynamic fluid assessment was feasible and reliable in the whole population and could provide additional information to the standard echocardiographic examination. Funding Acknowledgement Type of funding sources: None.

Resitivity measurements have been performed in La:Sr:Cu:Co:O ceramics in a frequency range from 5Hz – 10 9 Hz. A strongly frequency dependent resistance has been observed in La 2 CUO 4 which we interpret in terms of a smooth dielectric to metal transition due to localization effects.

Aim: Temporary rehabilitation on implants, whether fixed or removable, requires resin thickness that makes it aesthetic, durable and comfortable for the patient. However, these requirements are not always clinically attainable mainly due to the limited dimensions of the final structure. For this reason, it is desirable to create a framework with, on one hand constrained dimensions and, on the other hand, sufficient resistance to cyclic stresses. In addition, other factors must be taken into account, such as the economic aspect and the timing required to finalize the rehabilitation, to name some. One possibile solution to these requests was found to be the use of intraoral welding technique. The aim of this in vitro pilot study is to establish the minimum thickness of resin required to mask the metal framework used into intraoral welding technique. Methods: Three specimens were produced with three titanium bars of grade two (2 mm diameter) (Dentsply Implants Manufacturing; Germany): the first remained untreated, the second was sandblasted, the third was opacified; three specimens of dimensions of 12x6 mm were prepared of PMMA (BreCam Multicom, Bredent GmbH & Co.) of A3 color that differ in thickness 1, 2, 3 mm; three specimens were prepared of pink resin (Palapress, Kulzer dental) of the same size as the previous ones. These were then superimposed on each other and images of the different combinations were acquired with a spectrophotometer (Spectroshade Micro, MHT) evaluating the color difference (ΔE) at three points between the different specimens and their combinations on the basis of the application of the CIEL*a*b color space system. ANOVA test were used for statistical analysis. Results: The study shows that at least 3 mm of A3 color resin is required to mask the untreated or sandblasted metal framework 01). The two factors “thickness” and “metal condition” examined seem to influence the outcome ΔE significantly (p value

Aim: Periodontal regeneration is contingent on the adhesion and maturation of fibrin clot to a root surface exposed to periodontal disease. Root surface demineralization in vitro improves the formation of a stable union between the fibrin clot and the root surface. In scientific literature there are not studies of comparison that stand which demineralizing agent is the best in promoting fibrin clot adhesion. The aim of this study was to evaluate and compare the efficacy of six root conditionings in removing the smear layer and developing the fibrin clot in static and dynamic conditions. Methods: 36 single-root teeth extracted for periodontal disease were cut with a microtome in order to obtain 72 specimens that were divided in three groups: 24 samples not covered with blood, 24 covered with fresh human whole blood, 24 covered with blood and rinsed in a rotary shaker table (Vortex®). 4 specimens from each group were conditioned for 3 minutes with: physiological saline solution (FISIO) as the control group, saturated solution of citric acid 25% (AC), ethylenediaminetetraacetic acid 24% (EDTA), a solution of tetracycline 200mg/mL (TETRA), a solution of tetracycline and citric acid (TETRA+AC), Prefgel® and successively Emdogain® (EMD). Then the 48 samples from group 2 and 3 were covered with blood, which was allowed to coagulate for 20 minutes in a 37°C chamber. The blocks were rinsed and dehydrated under standardized conditions; specimens of group 3 were vortexed (100rpm). All the blocks were then sputtered with gold and analyzed with SEM. SEM images were evaluated by two blinded examiners, starting from the cementoenamel junction (CEJ), at 5 standardized points 2 mm distant from each other. A statistical analysis was performed. Results: EMD samples showed a more disorganized smear layer, in which is probably present the residual vehicle (propylene glycol alginate). However, in the 90% of all the specimens smear layer was found. AC treated samples showed a firmly adherent fibrin clot that covered the surfaces for the 70% of the specimens (the data was statistically relevant). Same results were found in TETRA+AC samples. The conditioning with EDTA, TETRA and EMD resulted in a sparsely organized clot worsened by the application of tensile forces, especially in TETRA samples. Only few blood cells without any clot organization were found in the control group, confirming that conditioning root surfaces improves the fibrin clot adhesion. Conclusion: The best formation of fibrin clot was observed for AC treated samples; this is probably due to the increase of root surface wettability caused by AC. The other root conditioning agents, even if lead to results better than the control group, are more susceptible to external forces and do not promote a stable fibrin clot adhesion.

Il Calibro persistente dell'arteria labiale (CPLA) di solito si presenta come papule asintomatica sul labbro inferiore e può essere facilmente mal diagnosticato come mucocele, emangioma, venoso lago, varici o fibroma. Quando è ulcerata, la diagnosi differenziale con il carcinoma squamoso più usuale. Qui riportiamo il caso di una donna di 25 anni con nessun precedente rilevante storia medica che ha presentato in maniera asintomatica, non ulcerata, un progressivo nodulo crescente (negli ultimi 5 mesi) sulla labbro superiore. In questo caso, la diagnosi è stata fatta clinicamente e confermato mediante analisi immunoistochimica. In conclusione i medici dovrebbero essere consapevoli di CPLA e dovrebbe essere incluso nella diagnosi differenziale di papule mucose labiali. A volte, l'analisi immunoistochimica è necessaria per effettuare una diagnosi corretta. Calibre persistent labial artery (CPLA) usually presents as an asymptomatic papule on the lower lip and can be easily misdiagnosed as a mucocele, haemangioma, venous lake, varix or fibroma. When it is ulcerated, squamous cell carcinoma is the most usual differential diagnosis. Here, we report a case of a 25-year-old woman with no previous relevant medical history who presented with a complaint of an asymptomatic, non-ulcerated, progressively growing nodule (over the last 5 months) on the upper lip. In this case, the diagnosis was made clinically and confirmed by immunohistochemical analysis. We conclude that clinicians should be aware of CPLA and it should be included in the differential diagnosis of labial mucosal papules. Sometimes, the immunohistochemical analysis is necessary to make a correct diagnosis.

We report a case of migration of a surgical localization wire from the breast to the abdomen. A 41‐year‐old female underwent presurgical needle localization of a deep‐sited left‐sided breast lesion. Migration of the localization wire in the chest wall occurred during the procedure documented by imaging. Computed tomography (CT) examination showed no evidence of the wire in the left lower lung field, no peritoneal free fluid, active bleeding, or abnormalities of abdominal organ, but a metallic‐density representing the localization wire was seen for a length of 13 cm from the right diaphragmatic crus to the right psoas muscle, close to the inferior vena cava. A following CT examination showed the wire partially outside the inferior vena cava and partially inside the right iliac vein. The wire was successfully taken out by an angiographic interventional procedure.

The theory of dc-electric field nonlinear susceptibility in the doped incipient ferroelectrics is developed in a random field approach. The calculations of the susceptibility X(E,T) had shown that the coefficients X (k) nl(T, n) in power serie of susceptibility X(E, T) = Σ X (k) nlE 2k (k = 0 and k = 1, 2, 3... correspond respectively to linear and nonlinear susceptibility of the first, second etc. order) diverge at the same temperature T = T m that depends on the impurity dipoles concentrations. The critical indexes of the divergency for the concentration of the dipoles which correspond to mixed ferroglass phase with coexistence of short- and long-range polar order were shown to be the same as those calculated in mean field approximation. The comparison of the theory with experimental data obtained for KTa 1-x Nb x O 3 (0.0075 ≤ x ≤ 0.05) is performed. The calculations describe the main peculiarities of temperature, electric field and concentrational dependence of observed nonlinear dielectric susceptibility. Since the temperature T m corresponds to the transition from dipole glass to ferroglass phase the transition is proven to be equilibrium one in the disordered ferroelectrics.

The oral complications of diabetes mellitus are generally considered to be no more than inevitable annoyances and, as such, have been the subject of relatively few scientific and clinical studies. This review highlights both the known correlations between oral disease and diabetes mellitus, such as those involving supporting tissues and oral mucosa, and those that are still a matter of debate, such as dental caries. In all cases, we carefully analyzed the pathogenesis of the disorder with a view to establishing a possible therapeutic approach, an aspect that currently appears to be overlooked. In view of the fact that the treatment of certain oral conditions, in particular periodontal disease, has been reported to improve metabolic control in diabetic patients, we conclude that diabetes mellitus-related oral diseases deserve adequate recognition and further investigation.

The resonant frequency in a piezoelectric crystal is strongly temperature dependent. This physical property may be exploited to measure small overheating of the material induced by a weak optical absorption. A sample of congruent LiNbO/sub 3/ is exposed to a laser beam, with a wavelength /spl lambda/ chosen inside the transparency window. One of the piezoelectric resonances is selected and used as an internal thermal probe to record both dynamical and steady state overheating induced by the residual absorption k of the material. A bolometer-type equation describing the time dependence of the sample temperature is used to determine k accurately, the capacitance-rather than frequency-being the temperature-sensitive electrical parameter of the resonance.

For PbZrO3 and PbZr0.99Ti0.01O3 single crystals the first order Raman light scattering spectra in the paraelectric phase have been analysed. In lead zirconate two kinds of crystals, with and without a transient phase, were investigated. It was found that temperature dependence of the defect-induced soft mode frequency in the paraelectric phase has a negligible contribution to the low-frequency dielectric response. From the point of view of strong dielectric relaxation in the range of 106–109 Hz, which originates in a disorder of the lead sites, crossover of the order-disorder and displacive type of antiferroelectric phase transition in lead zirconate is considered: the phase transition mechanism is neither purely displacive nor order-disorder. Contribution of physical phenomena responsible for the e(ω,T) dielectric response at low frequencies of an external electric field are described.

The molecular glass former trimethylheptane was studied by calorimetric, dielectric, ultrasonic, neutron scattering, Brillouin scattering, and depolarized light-scattering techniques. The molecular structure appears to be nearly spherical optically as indicated by the low depolarization ratio and dielectric susceptibility values. A preliminary mode-coupling theory (MCT) analysis of the light-scattering and neutron-scattering data indicates that ${T}_{C}\ensuremath{\gtrsim}150 \mathrm{K},$ at least 25 K above ${T}_{G}.$ The susceptibility minima were analyzed with the MCT interpolation equation, and disagreement between the light and neutron results was observed despite the apparent isotropy of the molecules.

This article explores correlates of retention among the 2.337 methamphetamine (MA) users entering public outpatient treatment programs in California from January 1, 1994 through September 30, 1997. A secondary analysis of data from the California Alcohol and Drug Data System (CADDS) was performed and predictors of drop-out before treatment completion (as measured by a retention of 180 days or more) were determined using logistic regression. Overall, 23.3% of MA users completed treatment, a rate similar to that for users of other drugs throughout California. As expected, MA users who were older (40 years or over), had less severe drug use patterns (used less than daily or did not inject), or who were under coerced treatment were significantly more likely to complete treatment that other MA users. Surprisingly, men were significantly more likely than women to drop out of treatment before 180 days. Until studies currently collecting primary data on MA treatment are completed, the present secondary analysis provides a useful foundation upon which future research and intervention strategies may be based.

Dielectric studies of a PbHfO3 (lead hafnate) single crystal undergoing two structural phase transformations at about 163°C (436 K) and 209°C (482 K) were performed in broad frequency and temperature range. Special attention was paid to the paraelectric phase. Investigations of the complex dielectric permittivity in the frequency range 10 Hz to 10 MHz revealed two relaxations of polydispersive and nearly monodispersive (Debye-like) character connected with space charge behaviour. In the frequency range of 106-109Hz a polar relaxation mode has been found and related to a disorder in the Pb sublattice. Temperature dependence of the dielectric step of this relaxation corresponds to a sharp anomaly of the e(T) function at the phase transition from the paraelectric to antiferroelectric state. Analysis of temperature evolution of the first order Raman light scattering spectra showed existence of a soft line at this transformation. Crossover of the displacive and order-disorder type of the transformatio...

The relaxation behaviour of two molecular glass-forming systems, namely sorbitol and maltitol, are investigated in the large temperature range relevant to the glass-transition. These data are obtained by combining three techniques, i.e. low-frequency mechanical spectroscopy, medium and high frequency dielectric spectroscopy, and viscosity measurements. This procedure allows to determine the relaxation map of these polyols on a wide time range [10-9-107 s]. Two different relaxation processes can be observed. The principal α-relaxation process exhibits a complex behaviour, comprising a non-Arrhenius temperature dependence above T g (supercooled liquid state), and an Arrhenius behaviour below T g (glassy state). A secondary β-relaxation is observed at higher frequencies with an Arrhenius temperature dependence. The secondary process appears in the same time-temperature range in both polyols. Consequently the molecular root of this relaxation is most likely the same in these complementary chemical systems. On the other hand, the time scale on which the α and β processes cross is very different for these two polyols. We relate this feature to the differences in the relative contributions of intra and inter-molecular interactions due to the different chemical architecture of these polyols.

The aim of this study was to evaluate the characteristics of resorption and the pattern of bacterial collonisation of polyglycolic and polylactic resorbable membranes under controlled experimental conditions. A removable cobalt-chromium device was applied to the lower jaw of 5 students for a period of 4 weeks. 8 composite resin chambers were glued to the device, 4 on each side of the mouth. A small piece of PLA/PGA membrane separated the composite chambers into 2 parts. The subjects wore the devices 24 h a day, except for the time necessary for oral hygiene procedures, during which time, the structure was submerged in a 0.2% chlorexidine solution. Every week, 2 of the chambers were removed; one was processed for scanning electron microscopy, to be observed both on the external and internal surface, and the other one for light microscopy examination. Both the electron microscopic and histologic observations showed a progressive increase in the plaque layer on the external surface of the membrane during the period of observation. The light microscopy showed an early invasion of the membrane, starting about 1 week after the exposure. On all the 3- and 4-week specimens, a complete bacterial invasion over the whole thickness of the membrane was visible. After 3 weeks of plaque accumulation, bacterial colonisation of the inner portion of the membrane was detectable in all the specimens. At 3-weeks, we observed in the light microscopy group in 4 out of 5 specimens, a large reduction of the thickness of the material and small voids in the membrane structure. In 1 specimen, the membrane was no more detectable. Only in 5 specimens of the 4-week group was the membrane still recognizable, though reduced to fragments. In conclusion, once exposed to the oral cavity, the PLA/PGA membranes start to resorb in the early stages: this process concludes itself between the 3rd and 4th weeks of exposure. However, the particular conditions of the experimental design nevertheless classify this study as an in vitro, more than as an in vivo experimentation.

A systematic analysis of the dielectric constant as a function of temperature in SrTiO 3 : Ca crystals with Ca content of 0.0020, 0.0032, 0.0055. 0.0058, and 0.0110 shows that the Barrett parameters are clearly modified by the Ca content. We have found for each Ca concentration the temperature below which the contribution of the Ca induced clusters becomes sizeable. The values obtained for the fitted parameters in the Barrett formula allow us to trace a boundary between the low-temperature quantum paraelectric and ferroelectric regimes.

The active part of a linear translator is a shape memory alloy (SMA) made of nickel and titanium (NiTi) wire which is to be thermally cycled. We have achieved heating using electromagnetic radiation with a magnetic sheath and low-frequency waves at 8 kHz and without magnetic sheath and radio frequency waves at 28 MHz. The heating is equivalent for these two arrangements. In vitro experiments have been confirmed by computer simulations of the radiation distribution within the implant. We thus show that electromagnetic radiation could specifically heat a NiTi wire inside a stainless steel tube without heating the tube. An application could be a femoral prosthesis for the lengthening of the bone.

The dielectric permittivity and the dielectric losses of PbZr1-xTixO3 (x=0.03, x=0.04, x=0.05) ceramics doped with 1% Nb2O5 were investigated as functions of frequency and temperature. A large and unambiguous dielectric relaxation is detected at high frequency and is shown to be strongly dependent on the temperature. The minimum of the relaxation time and the maximum of the relaxation strength appear to be clearly connected with the ferroelectric-paraelectric phase transition.

Premature exposure of membrane in the oral cavity is considered the most common complication as well as a reason for failure or incomplete success of guided tissue regeneration, as the exposed membrane undergoes plaque accumulation. A method to control, or at least to reduce the bacterial invasion of the membrane allowing a delay in the membrane removal, could be of clinical interest. The purpose of the present study was to evaluate the possibility of treating, with topical chlorhexidine application, the bacterial colonization of exposed membranes. A special device was developed in order to evaluate, under an experimental environment, the bacterial colonization. This device was made from a removable acrylic denture base to which 5 gold cups were attached. The cups consisted of an internal compartment, isolated from the oral cavity by a GTAM membrane, and an external compartment exposed to the oral environment. 3 healthy subjects had this device fitted, bilaterally, in the molar-premolar region of the upper jaw. The cups of one side of each subject had 0.2% chlorhexidine gluconate gel applied 2× a day for 1 min, whereas those of the other side served as controls. 12 cups were removed after 2 weeks and the remainder removed after 1 month. The non-treated control specimens were characterized by greater amounts of plaque accumulation. In all the test sites, plaque deposits increased in thickness and quantity during the 4 weeks of the experiment. Complete invasion of the membrane and initial colonization of its internal surface were observed only in 4-week specimens. A relatively simple flora consisting mainly of cocci and short rods, was found in bacterial deposits forming under the influence of chlorhexidine, whereas in non-treated specimens, it was possible to observe a more mature and complex plaque, composed mostly of filamentous bacteria. In conclusion, topical application of chlorhexidine gel is an effective method of reducing plaque and calculus formation on the surface of GTAM membranes exposed to the oral cavity for up to 4 weeks. This study has, however, failed to demonstrate the capacity of chlorhexidine to prevent or to retard bacterial penetration through the thickness of the inner portion of the membranes.

We have grown powders and ceramics of Lead Titanate (PbTiO3) doped with Lanthanum and Copper. The incorporation of Cu ions does not change the lattice properties of PbTiO3: La. On the other hand, we demonstrate that the conductivity properties of PbTiO3: La, Cu may be swept over 12 orders of magnitude.

We report lattice and electronical properties of BaTiO3:La powders and ceramics with 0

The technique of guided tissue regeneration using expanded polytetrafluoroethylene (ePTFE) membranes has been shown to be effective in implant dentistry (bony defects, extremely thin alveolar ridges, and implants placed in fresh extraction sockets). One of the drawbacks associated with the use of membranes is their premature exposure with consequent bacterial contamination. The aim of this study was to examine the possibility that oral bacteria migrate through the occlusive portion of ePTFE membranes and to determine the time needed for microorganisms to pass from the outer surface to the inner surface of the membranes. A removable acrylic device was adapted to the molar-premolar region of one quadrant of the jaws in each of three volunteers. Five cylindrical teflon chambers were glued to the buccal aspect of each device. The chambers were divided into two rooms separated by the inner portion of a ePTFE membrane. The outer room was open to the oral cavity allowing plaque accumulation; the inner room was isolated from the oral cavity by the ePTFE membrane. One of the 5 chambers was completely closed and used as control. The test period lasted for 4 weeks. Every week, one chamber was removed from each device and processed for scanning electron microscopic and histologic examinations. Our study showed the possibility that oral bacteria may contaminate ePTFE membranes exposed to the oral cavity. One specimen showed partial bacterial penetration after 2 and 3 weeks, but after 4 weeks, all membrane specimens demonstrated bacterial contamination.(ABSTRACT TRUNCATED AT 250 WORDS)

Significant discrepancies were generally reported in the dynamics of BaTiO3 between results deduced from various experimental techniques. Here dielectric and quasi-elastic light scattering measurements are investigated on high-quality BaTiO3 crystals. We show that two relaxators have to be introduced below the soft-phonon frequency. A complete dielectric dispersion in a very wide frequency range is thus achieved which consistently relies the high-frequency dielectric results and the Raman data. There is also a qualitative agreement between our two-relaxator model and the dynamics which were deduced some time ago from EPR experiments.

Since its discovery, the SrTiO3: Ca system is known to exhibit a number of features which were thought to arise from an impurity induced disorder. Non-linear dielectric measurements are used to obtain a more quantitative insight into this disorder. For 0.001 < xCa < 0.05, it is found that the non-linear susceptibility diverges at low temperatures. This is similar to what was previously reported in the dielectric random system KTaO3: Na. A method is proposed to quantify the contribution of the disorder to the non-linearities. It is found that the deviation from a true ferroelectric behaviour is not enough to call the low-temperature phase of SrTiO3: Ca a glass one. The maximum non-linearity observed for xCa = 0.003 and 0.004 decreases for higher xCa contents. It is shown that a simple model of temperature dependent dipole moment may account for both the linear and non-linear dielectric behaviour of SrTiO3: Ca.

The existence of polarization clusters in the cubic phase of the ABO3 compounds has been revealed for a long time by various experimental techniques, including now the direct measurement of the dielectric dispersion. These clusters are described in terms of correlated displacements of the B ions in the 〈111〉 directions, out of the centre of the oxygen cage. In this paper, we show how the improvement of both the crystalline quality and the performance of the experimental devices led to the actual concept of “relaxator ferroelectrics”. Some experimental results are reviewed within the scope of this relaxation concept and its microscopic origin is questioned.

Odontogenic myxoma is usually a benign neoplasm, although it has the ability to infiltrate surrounding tissues thus becoming locally invasive. Furthermore, it has a moderately high recurrence rate and can sometimes display a really aggressive behaviour. An unusual case of a 48-y-old woman in whom odontogenic myxoma recurred 11 years after excision of the primitive lesion is reported. Although rare, the possibility of malignant evolution led us to consider which was the most appropriate management of both the neoplasm and the recurrence. A careful assessment of the clinical, radiographical, tomographical, histological and, if necessary, immunohistochemical features of the lesion allows a distinction to be made between lesions that are only locally invasive and the rarer, more dangerous aggressive lesions. In the first case we suggest that, where possible, a conservative treatment should be preferred, followed by close monitoring of the lesion over time. Since odontogenic myxoma is limited to the facial bones, excision may be uselessly disfiguring, above all in young patients. More aggressive surgical treatment should be reserved for lesions for which there is a strong suspicion of malignant transformation.

Duplex Doppler ultrasound allows the evaluation of thyroid gland vascular flow by spectral analysis assessment. The objective of this prospective study was to employ Doppler ultrasound to evaluate the possible functional changes produced in normal subjects following intravenous iodized contrast medium injection.The study was performed on 30 non-consecutive subjects, enrolled according to some inclusion criteria: male gender, age ranging between 19 and 70 years, absence of chronic liver disease, absence of thyroid disease, absence of sonographic changes in the thyroid gland, negative history for recent intravenous contrast medium administration. All patients were scheduled for a contrast-enhanced CT study. A non-ionic contrast medium (iomeprol) was employed at 350 mgI/mL concentration, 130-140 mL volume, and 2-4 mL/sec. injection rate. The Doppler ultrasound examination was carried out immediately before and about 30 minutes after the CT study. The systolic velocity, diastolic velocity, the resistive index, and the pulsatility index were measured at the level of one of the four thyroid arteries.In most cases a slightly increasing trend of the four parameters considered was noted but none of these showed a statistically significant change. The mean systolic velocity was of 33 cm/sec. in the basal measurement and of 39 cm/sec. in the post-contrast measurement. The variation was positive in 17 cases, negative in 12, and absent in 1. The mean diastolic velocity was of 13 cm/sec. in the pre-contrast evaluation and of 14 cm/sec. in the second evaluation. The change was positive in 14 cases, negative in 12, and absent in 4. The mean resistive index was of 0.55 in the basal analysis and of 0.59 in the post-contrast one. The variation was positive in 20 patients, negative in 9, and absent in 1. The mean pulsatility index was of 0.99 in the basal measurement and of 1.14 in the second measurement. The change was positive in 23 subjects, negative in 5, and absent in 2.Our series shows that no significant change in Doppler spectral analysis of thyroid flow is evident after administration of iodized contrast media, at least in euthyroid subjects and with the contrast doses and the examination intervals employed in our study. Doppler ultrasound is confirmed as an accurate and objective procedure in the evaluation of thyroid gland flow and may represent a useful tool in functional studies, as well as clinical applications in the assessment of thyroid gland disorders.

Introduction Severe asthma with fungal sensitisation (SAFS) in adults is associated with reduced lung function and increased morbidity [ EurRespir J 2006; 27 :615–26, Am J RespirCare Med 2009; 179 :11–18]. We hypothesised that fungal sensitisation in children with severe, therapy-resistant asthma (STRA) is associated with increased symptoms, medication use and airway inflammation, and reduced lung function. Methods STRA was defined as before [ Lancet 2010; 376 :814–25]. All children had been through a detailed assessment to optimise adherence and other aspects of basic management, as far as possible. We retrospectively evaluated 166 patients (median age at referral 11.7 years [4;17]; 61% males). SAFS (n=76) was defined as specific IgE (spIgE) or skin prick test (SPT) positivity to any of Aspergillus fumigatus, Alternaria alternata or Cladosporium herbarum . Non-sensitised patients (n=90) had negative spIgE and SPT to all fungal allergens tested. Age of onset, atopy, symptoms (asthma control test), medication usage, lung function and airway inflammation were assessed. Results More boys had SAFS (57/76 (75%) vs 43/90 (48%), p Allergy 2007; 62 :1379;86] (16 mm [0;38] vs 9 mm [0;36], p 1 (1.4 L [0.5;3.8], vs 1.9 [0.7;4.3], p=0.008) and lower FVC (2.3 L [0.6;4] vs 2.6 [0.8;5.5], p=0.045). Bronchodilator reversibility was more frequent in SAFS (n=59/73 (81%) vs 42/81 (52%), p Conclusions Children with STRA and fungal sensitisation had lower lung function, earlier asthma onset, more atopy and more bronchodilator responsiveness. There is a need for a randomised controlled trial of antifungal therapy in paediatric SAFS.

This experimental work came out from clinic observations. The deal is to check the factors that can provoke the fracture of the more commonly in oral surgery used burrs, and then reduce the correlated risks to this event. Besides a fracture surface characterisation is done to point out the presence of production and/or stoking defects that can alter the structure.Four batches of new surgical burrs (type Lindemann) were examined for a total of 40 samples. The first batch was used as control, the other three were submitted to 5, 10 and 20 sterilisation cycles respectively. Before each cycle disinfectant washing was done. All the samples were then mechanical tested (four point bending test) for the determination of the ultimate tension strength. The fracture surfaces were observed at SEM; a comparison with that of burrs broken during surgery operations was done.The new burrs did not show working defects. The washing and sterilisation processes did not provoke any corrosion attack.No significant differences among the batches were detected from the mechanical tests as well as from micrographic observations.

Morphea, lichen planus and vitiligo are common diseases, but seldom associated. Morphea or lichen planus in the lips have not frequently been reported, and an associated localization of both lesions in the lip mucosa is indeed a rare event. A case of morphea and lichen planus localized in the upper lip mucosa in a patient with vitiligo is reported. Immunohistochemistry revealed a clear prevalence of T-lymphocytes in the inflammatory infiltrates of morphea and in the band-like infiltrate of the lichen, a finding consistent with previous reports of morphea, lichen planus, and vitiligo. The inverse ratio found between CD8+ and CD4+ lymphocytes, compared to other reports, seems to confirm that the pathogenesis of morphea and lichen planus evolves through different stages. The present report, besides presenting a rare case, may prompt to consider a common pathogenesis among morphea, lichen planus and vitiligo.

The potential dental materials have of inducing mouth diseases is well known, and various methods have been developed to investigate this phenomenon. Among these there are histological studies of the pulp and periodontium exposed to dental materials, both in vivo and in vitro in humans and animals. Other studies are based on the clinical observation of the effects induced by dental materials. Aim of the paper is to evaluate the use of flow cytometry to analyse crevicular fluid to study its content in terms of inflammatory cells and inflammation mediators.Samples of crevicular fluid were collected by aspiration using a bevelled needle mounted on a 5 ml syringe from patients without periodontitis and with periodontitis and multiple heterogeneous dental restorations. This method was adopted since it allows to place the cells of the fluid in suspension. Part of the fluid was analysed by cytology and part by flow cytometry.In the patients without periodontal disease cytological examination revealed the presence of desquamated epithelial cells and colonies of cocci, rods and spirochaetae. In the patients with periodontal disease the same examination revealed, besides the above, the presence of inflammatory cells. Flow cytometry confirmed the findings of cytological examination, thus proving to be an effective method for studying crevicular fluid.This method allows to identify specific inflammatory cells or mediators of inflammation in crevicular fluid and may therefore prove to be very useful in the study of alterations induced by some dental materials at the level of the gingival sulcus.

In all ferroelectric perovskites, intentionally introduced or “unwanted” point defects do play a role in the dielectric spectra and in the conductivity.

The aim of this study was to evaluate the characteristics of resorption and the pattern of bacterial collonisation of polyglycolic and polylactic resorbable membranes under controlled experimental conditions. A removable cobalt-chromium device was applied to the lower jaw of 5 students for a period of 4 weeks. 8 composite resin chambers were glued to the device, 4 on each side of the mouth. A small piece of PLA/PGA membrane separated the composite chambers into 2 parts. The subjects wore the devices 24 h a day, except for the time necessary for oral hygiene procedures, during which time, the structure was submerged in a 0.2% chlorexidine solution. Every week, 2 of the chambers were removed; one was processed for scanning electron microscopy, to be observed both on the external and internal surface, and the other one for light microscopy examination. Both the electron microscopic and histologic observations showed a progressive increase in the plaque layer on the external surface of the membrane during the period of observation. The light microscopy showed an early invasion of the membrane, starting about 1 week after the exposure. On all the 3- and 4-week specimens, a complete bacterial invasion over the whole thickness of the membrane was visible. After 3 weeks of plaque accumulation, bacterial colonisation of the inner portion of the membrane was detectable in all the specimens. At 3-weeks, we observed in the light microscopy group in 4 out of 5 specimens, a large reduction of the thickness of the material and small voids in the membrane structure. In 1 specimen, the membrane was no more detectable. Only in 5 specimens of the 4-week group was the membrane still recognizable, though reduced to fragments. In conclusion, once exposed to the oral cavity, the PLA/PGA membranes start to resorb in the early stages: this process concludes itself between the 3rd and 4th weeks of exposure. However, the particular conditions of the experimental design nevertheless classify this study as an in vitro, more than as an in vivo experimentation.