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Aim: To compare the clinical and radiographic outcomes of flapless procedure alone or in combination with enamel matrix derivatives (EMD) in the treatment of deep intrabony defects. Materials and Methods: Forty‐six patients re‐evaluated after non‐surgical therapy were randomly assigned to the test (flapless with EMD) or control group (flapless alone). Clinical measurements were recorded pre‐surgery and at 6 and 12 months after surgery, and radiographic measurements were taken pre‐surgery and after 12 months. Results: Forty‐six patients completed the study. Improvements were observed in both groups at 12 months for mean clinical attachment level (CAL) gain, with significant differences between test (3.9 ± 1.1 mm) and control groups (3.0 ± 1.2) (p =.017). Probing pocket depth (PPD) reduction (4.0 ± 0.7 vs. 3.3 ± 1.4 mm) was also near to statistical significance (p =.051). Also, more sites achieved successful composite outcome measure (final PPD ≤ 4 mm and CAL gain ≥3 mm) for the regenerative treatment in the flapless + EMD group (82.6% vs. 52.2%; p =.028). In terms of radiographic outcomes, EMD yielded a greater defect bone fill than flapless treatment alone (3.0 ± 1.0 mm vs. 1.8 ± 1.5 mm; p <.001). Conclusions: The additional application of EMD during the flapless procedure for intrabony defects slightly improved clinical and radiographic outcomes. ClinicalTrials.gov identification number: NCT05456555. [ABSTRACT FROM AUTHOR]

The article offers information on the advancements in perovskite solar cells (PSCs), emphasizing their efficiency improvements over the past decade. Topics include the exploration of various strategies to enhance the quality of the perovskite layer, such as using excess precursors, additives, or passivating agents.

The development of more accurate and sensitive diagnostic techniques is a key factor in efforts to improve cancer survival rates. The technique of infrared aperture fibre scanning near‐field optical microscopy (IR‐SNOM), together with radiation from the infrared free‐electron laser (IR‐FEL) on ALICE at Daresbury Laboratory (UK), has been used to obtain IR images of a crypt‐like feature and the surrounding tissue; the tissue was taken from a patient with oesophageal adenocarcinoma and with a history of Barrett's oesophagus. We have shown that the DNA signal is enhanced relative to other contributions in the region of the crypt, and the glycoprotein signal shows a less pronounced increase in the region of the crypt. The Amide II signal is found to be anti‐correlated with the DNA and glycoprotein profiles. The absorbance of the Amide II signal is found to differ for three different types of cancer tissue. High‐resolution IR images of the crypt reveal additional structure that would not be resolved in diffraction‐limited techniques. [ABSTRACT FROM AUTHOR]

Background: Presence of epithelial desquamation, erythema, and erosions on gingival tissue is usually described in the literature as desquamative gingivitis (DG). A wide range of autoimmune/dermatologic disorders can manifest as DG, although the two more common are oral lichen planus and mucous membrane pemphigoid. The aim of this study is to investigate prevalence of 11 periodontopathogenic microorganisms in patients with DG and to compare it with the microbiologic status of individuals affected by plaque-induced gingivitis (pGI).Methods: Cross-sectional clinical and microbiologic data were obtained from 66 patients (33 in each group). Subgingival plaque samples were analyzed using semiquantitative polymerase chain reaction analysis.Results: Statistically significant difference, but with little clinical significance, was observed in gingival conditions between the two groups, probably due to the worse home control hygiene of patients with DG. Prevalence and levels of Aggregatibacter actinomycetemcomitans, Eikenella corrodens, and Fusobacterium nucleatum/periodonticum were statistically higher in samples from patients with DG than in those with pGI. In multivariate regression models, subgingival colonization of A. actinomycetemcomitans and F. nucleatum/periodonticum was not statistically associated with DG, whereas, high levels of E. corrodens were associated with 13-fold increased odds for DG.Conclusions: Microbiologic differences were found in subgingival plaque for patients with DG and pGI. This may suggest possible association between periodontal pathogens and DG. [ABSTRACT FROM AUTHOR]

Background and objective The subepithelial connective tissue graft ( SCTG) is the most widely used procedure for the treatment of gingival recession defects. Little is known, however, as to whether the apposed gingival flaps are more predisposed to develop plaque-related inflammation compared to healthy sites. This has salient clinical implications, as the long-term results of root coverage will depend largely on the level of inflammation of the grafted tissue. Methods In the present split-mouth case-control study, clinical and biomolecular parameters were used to assess the level of inflammation of periodontal sites 12 mo after treatment with SCTG (test) and healthy non-treated gingivae (control) following the induction of plaque-related gingivitis in 19 patients. Results The data showed that test sites had a significantly ( P < 0.05) lower gingival index and angulated bleeding score compared to control sites ( gingival index = 1.05 ± 0.23 vs. 1.34 ± 0.47; angulated bleeding score = 0.34 ± 0.37 vs. 0.61 ± 0.39) after induction of experimental gingivitis, whereas the plaque index did not differ in the two groups ( P > 0.05). With regard to the biomolecular parameters, baseline levels of the proinflammatory cytokine interleukin-1β were higher in the gingival crevicular fluid of test sites. However, control sites exhibited more pronounced increase in the levels of interleukin-1β compared to test sites, upon plaque accumulation, so that the final concentration was similar in both groups. No changes were recorded in the gingival crevicular fluid volume. Conclusion Analysis of the data demonstrates that the sites of gingival recession treated with SCTG develop a lower degree of plaque-induced inflammation compared to healthy gingivae. This strongly suggests that SCTG does not predispose to inflammation and to further gingival recession and makes it a safe technique in the treatment of gingival defects. [ABSTRACT FROM AUTHOR]

Connective tissue grafts are routinely procedures in the treatment of gingival defects. The clinical success of the gingival tissue graft procedures anyway should ensure not only the aesthetic integration between the tissues but also the physiological activity of the graft in terms of sensitivity and immunity because the skin and the mucosae constitute the first natural aspecific borders against pathogens. The aim of this paper was to investigate nervous net recovery after connective graft procedure, in relation with sensorial alteration in the injured area. Results showed that there is a close link among the number of Merkel cells and the alteration of sensations. Merkel cells can be found isolated standing in the basal layer, supposed to have neuroendocrine functions in the epithelia or in larger group not associated with nerves; when found in association with nerves they are named Merkel complexes, acting as slow adapter mechanical receptor. Our data can be explained in two ways: Merkel cells increase as a consequence of tissue injury, a sort of “SOS cells” that secrete neuroendocrine signals to guide tissue healing; as an alternative the presence of the Merkel cells could be read as a derailment of tissue regeneration with the stop of cellular differentiation in the direction of an abnormal proliferation, a sort of mad stem cell. J. Cell. Physiol. 224:205–209, 2010 © 2010 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Introduction: The aim of this study is to investigate the nanocrystallization of steels caused by the transformation from the austenitic to the martensitic phase induced by a severe plastic deformation (SPD) treatment. In this framework, we applied an air blast shot peening treatment, which is a simple protocol widely used for industrial purposes. Methods: AISI 286 and AISI 316 specimens were peened for different times and polished using diamond pastes in order to remove corrugations higher than 1 μm. The characterization of the steel surfaces was performed by atomic force microscopy (AFM) operating in contact mode. Additional EDXD measurements were performed to confirm the phase transition. Results and Discussion: An AFM-based characterization at nanometric level of the steel surfaces is provided. When the peening exceeds a threshold time that, as expected, depends on the steel composition, a uniform nanostructuration is detected. It is well known that such rearrangement is associated to the growth of a martensitic phase. To date, AFM has been employed in this field only for few applications and to solve specific problems. On the other hand, our results demonstrate that this is a useful technique for the characterization of hardened surfaces, especially when non-destructive sample preparation treatments are required. Moreover, we show that AFM can be a useful tool also for in situ industrial diagnostics of metallic parts. [ABSTRACT FROM AUTHOR]

Porous glass-ceramics is an extremely important material to be used in combination with metallic nanolayers as a Surface-Enhanced Raman Scattering (SERS) substrate for biological and chemical analysis, demonstrating excellent biocompatibility and chemical inertness. These materials show their own Raman background signal lateral distribution, mostly from crystalline skeleton, which has to be considered. A nano-Raman setup using the optical fibre of a Scanning Near-Field Optical Microscope (SNOM), working in collection mode, is described and applied for mapping of such glass-ceramic. The collected Raman signal of Ti and P containing phase distribution in this near-field geometry reaches spatial resolution around 50 nm. [ABSTRACT FROM AUTHOR]

Human HaCaT cells, exposed for 24 h to a 1 mT (rms) 50 Hz sinusoidal magnetic field in a temperature-regulated solenoid, suffer detectable changes in their biochemical properties and shapes. By using infrared wavelength-selective scanning near-field optical microscopy, we observed changes in the distribution of the inner chemical functional groups and in the cell morphology with a resolution of 80–100 nm. [ABSTRACT FROM AUTHOR]

We present the implementation of a tapping-mode aperture scanning near-field optical microscope (Tapping-SNOM) to a Binder CB incubator (Istituto di Struttura della Materia, Rome, Italy). The microscope operates in the intermittent contact mode using a nonbent optical fibre allowing to reduce the perturbation exerted on the sample, while the incubator maintains a constant temperature, humidity and CO2 level. This instrument can maintain and analyse in a controlled environment different samples, both organic and nonorganic. In particular, the Tapping-SNOM can study different cell lines at nanometric resolution and in physiological buffer, following the evolution of the living cells almost indefinitely. We will present several examples of the capabilities of the tapping scanning near-field optical microscope in the study of different lines of living cells, showing corresponding topographical, optical or phase-lag images of the live samples, evidencing the excellent stability, versatility and resolution of the system. [ABSTRACT FROM AUTHOR]

In this work, we report a method to observe soft X-ray radiographs at nanoscale of various kind of samples, biological and metallic, stored in a thin layer of lithium fluoride, employing scanning near-field optical microscopy with an optical resolution that reaches 50 nm. lithium fluoride material works as a novel image detector for X-ray nano-radiographs, due to the fact that extreme ultraviolet radiation and soft X-rays efficiently produce stable point defects emitting optically stimulated visible luminescence in a thin surface layer. The bi-dimensional distribution of the so-created defects depends on the local nanostructure of the investigated sample. [ABSTRACT FROM AUTHOR]

Due to its surface sensitivity and high spatial resolution, scanning near-field optical microscopy (SNOM) has a significant potential to study the lateral organization of membrane domains and clusters. Compared to other techniques, infrared near-field microscopy in the spectroscopic mode has the advantage to be sensitive to specific chemical bonds. In fact, spectroscopic SNOM in the infrared spectral range (IR-SNOM) reveals the chemical content of the sample with a lateral resolution around 100 nm ( Cricenti et al., 1998a, 1998b, 2003 ). Model lipid membranes were studied by IR-SNOM at several wavelengths. Topographical micrographs reveal the presence of islands at the surface and the optical images indicate the formation of locally ordered multiple bilayers – both critically important features for biotechnology and medical applications. [ABSTRACT FROM AUTHOR]

The interaction of the cytotoxic metals cadmium, zinc, and lead with pancreatic cells was studied by atomic force/lateral Force microscopy (AFM/LFM), an approach that provides both topographic (with nanometer scale lateral resolution) and chemical information on the membrane. Different morphological modifications of the overall cell shape and roughness took place as consequence of 100 μM metal-dependent treatment. Furthermore, after exposure to Cd(Cl2) and Zn(Cl2), but not Pb(Cl2), the LFM images revealed several areas of the cell's surface showing lateral friction contrasts that have been interpreted as marker of different alterations of the cell physiology induced by the metal loading. Thus, the coupling of LFM detection to topographic AFM characterization allows to distinguish, through a nondestructive and surface characterising approach, between different metal-induced cytotoxic effects on cells. In this framework, the role of the LFM as an important tool to discriminate between different alteration of a biological system has to be highlighted. Microsc. Res. Tech., 2007. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

In this study we have employed atomic force microscopy (AFM) and scanning near-field optical microscopy (SNOM) techniques to study the effect of the interaction between human keratinocytes (HaCaT) and electromagnetic fields at low frequency. HaCaT cells were exposed to a sinusoidal magnetic field at a density of 50 Hz, 1 mT. AFM analysis revealed modification in shape and morphology in exposed cells with an increase in the areas of adhesion between cells. This latter finding was confirmed by SNOM indirect immunofluorescence analysis performed with a fluorescent antibody against the adhesion marker β4 integrin, which revealed an increase of β4 integrin segregation in the cell membrane of 50-Hz exposed cells, suggesting that a higher percentage of these cells shows a modified pattern of this adhesion marker. [ABSTRACT FROM AUTHOR]

We used air operating atomic force microscopy (AFM) to study several morphological modifications of human erythrocytes, artificially produced by addition of exogenous agents including phospholipids, low ionic strength media and drugs. Most experiments were performed on unfixed samples to avoid treating red blood cells (RBCs) with chemical agents that can, in principle, induce morphological alteration. After detailed quantitative AFM characterization, the artificially produced abnormally shaped RBCs were compared with cells that occur with high incidence in blood pathologies. This morphological approach suggests a new strategy to describe and understand the biochemical and/or mechanical modifications responsible for the underlying pathologically induced changes and prove AFM to be a suitable tool to study erythrocyte deformation. [ABSTRACT FROM AUTHOR]

Hydrogen chemistry in thin films and biological systems is one of the most difficult experimental problems in today's science and technology. We successfully tested a novel solution, based on the spectroscopic version of scanning near-field optical microscopy (SNOM). The tunable infrared radiation of the Vanderbilt free electron laser enabled us to reveal clearly hydrogen-decorated grain boundaries on nominally hydrogen-free diamond films. The images were obtained by SNOM detection of reflected 3.5 µm photons, corresponding to the C-H stretch absorption, and reached a lateral resolution of 0.2 µm, well below the λ/2 (λ = wavelength) limit of classical microscopy. [ABSTRACT FROM AUTHOR]

We used a combination of internal photoemission and of near-field optical microscopy (SNOM) to study the lateral variations in solid interface properties such as energy barriers and electron–hole recombination. In particular we investigated the fully formed Pt–GaP, Au–GaAs, Au–SiNx–GaAs and PtSi–Si Schottky barriers. Our approach enabled us to measure large lateral variations in the photocurrent with spatial resolution on the nanometric scale. Due to the ability of SNOM to supply parallel topographic information, we observed photocurrent variations from zone to zone that only correlated in a few cases with local variations in surface morphology. We assigned the uncorrelated fluctuations to local variations in the interface stoichiometry, the presence of interface states induced by the metallic overlayer and to defect states at the junction. Furthermore, by tuning the photon energy and applied bias we were able to measure the surface distribution of the diffusion length. [ABSTRACT FROM AUTHOR]