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After tooth extraction, a modeling and remodeling phase of bone and soft tissues occurs. It has been fully demonstrated that bone resorption as high as 50% can take place regarding ridge width and a variable amount concerning ridge height, making it difficult to perform implant surgery.Active members of the Italian Academy of Osseointegration (IAO) participated in this Consensus Conference, and three systematic reviews were conducted before the meeting to provide guidelines on alveolar ridge preservation procedures. The systematic reviews covered the following topics: (1) What material best preserves the dimensions of the ridge horizontally and vertically?; (2) what material favors the formation of the highest quantity of new bone?; (3) which technique would best seal the socket?; and (4) what effect does alveolar ridge preservation have on soft tissues?The main conclusions reached by the assembly were that alveolar ridge preservation is advisable after dental extraction, particularly in esthetic areas, in proximity of anatomical structures (ie, maxillary sinus, inferior alveolar nerve, and mental foramen), whenever the treatment plan requires delayed placement, and whenever patients ask to postpone implant insertion for various reasons. Socket debridement is advised before the use of a "regenerative material," and xenograft is considered the gold standard material to maintain ridge dimensions. Another indication is antibiotic therapy, which is recommended in the case of alveolar ridge preservation (amoxicillin 2 g 1 hour before the intervention and 1 g every 12 hours for 6 days). A membrane or autologous soft tissue should be used to seal the socket and protect the regenerative material, and the indicated reentry time (implant insertion) is 4 to 6 months.This Consensus Conference agreed that the adoption of alveolar ridge preservation can effectively prevent physiologic bone loss, especially in esthetic areas. It is recommended to cover the xenograft material with a membrane or autologous soft tissue, and antibiotic therapy is advisable.

The scientific community has definitely demonstrated the importance of the use of mouthwash in daily oral hygiene. In our pilot study, we tested the effectiveness of a novel mouth rinse containing sea salt, xylitol, and lysozyme. Streptococcus mutans (S. mutans) growth, and plaque index in adolescent patients aged 14&ndash, 17 years, were observed. The bacterial load was investigated by in vitro microbiological analysis, the plaque index was assessed through the O&rsquo, Leary&rsquo, s Plaque Control Record (PCR). The study has shown that the use of a sea salt-based mouthwash in daily oral hygiene reduces the bacterial levels of S. mutans (p &lt, 0.01) linked to the combined action of xylitol and lysozyme, together with the action of sea salt. Our preliminary data confirm and improve the main results reported in the scientific literature on the importance of the use of xylitol, lysozyme, and sea salt in oral health.

Background: The discovery of the vaccination technique was revealed by Edward Jenner in 1796, which represented the first scientific attempt to control an infectious disease by vaccines, followed by other important studies carried out by Pasteur and Koch, and Sabin, who developed the first technique to attenuate the virus. In recent decades, numerous scholars have begun to create dangerous theories against the effectiveness of vaccines through scientifically invalid or fraudulent studies. Aim: This critical review of the literature aims to analyze the main factors that have undermined the credibility of vaccines in the general population, disproved false information and emphasized the benefits of vaccines over the last 200 years. Discussions: Unfortunately, several studies have been carried out without the proper scientific attention. The most impacting example is the study published by Andrew Wakefield in the Lancet journal who tried to correlate vaccines with the development of autism: this publication was withdrawn from the journal a few years after its publication, but the impact of incorrect scientific studies, fake news, and ambiguous healthcare policies have led to a general adverse opinion about the effectiveness of vaccines. Conclusion: The excess of uncontrolled information is a serious concern during the Coronavirus pandemic. Modern science must tackle this problem with a better willingness to communicate the clinical studies to those who cannot understand medical information. Nevertheless, a reliable science must also limit the distribution of studies that do not meet the basic criteria of methodological rigor and certainty of results in order not to incur confusion in the scientific community.

BACKGROUND: Probiotics are living microorganisms that confer a health benefit when administered in adequate amounts. There is evidence in the current literature about the importance of probiotic use in pregnancy. The early supplementation of probiotics in the perinatal and postnatal periods seems to have a positive impact on the overall mother’s health and future health of infants. AIM: Our pilot study aimed to test the ability of specific probiotics strains in combination with the kiwi-unique enzyme actinidin to improve the availability of folic acid in 20 pregnant women. METHODS: We investigate 20 pregnant women in early (4–10 weeks) (6 patients), intermedium (11–20 weeks) (6 patients), and late (21–30 weeks) (8 patients) pregnancy. RESULTS: Our findings show that the tested formula promotes increased concentration of serum folate in women’s blood and contributes to the control of blood sugar and body weight, regardless of the gestational period (early, intermediate or late). CONCLUSIONS: Our data support the main results reported in the scientific literature about the importance of probiotics intake in pregnancy.

Background: Dysbiosis is related to changes in the composition and behaviour of intestinal microbiota, which may contribute to an age-related decline in metabolic and immune system functioning (immune-senescence). Objective: The microbiota-targeted dietary and probiotic interventions have been shown to favorably affect the host health by an enhancement of antioxidant activity, improving immune homeostasis, suppression of chronic inflammation, regulation of metabolism and prevention of insulin resistance. Results: In our study, the use of specific probiotics strains improved the serum concentration of glycemic markers, thereby promoting better overall health. Conclusion: Probiotics may help correct defects in the gut microbial environment improving metabolic parameters, such as blood sugar levels, glycosylated hemoglobin and a decrease in body weight.

Statement of problem Few investigations concerning the use of pterygoid implants have reported reproducible and consistent data, making survival data controversial. Purpose The purpose of this clinical study was to investigate the 1-year survival and success rates of pterygoid implants and prostheses in participants affected by severe atrophy of the posterior maxilla requiring a complete-arch immediate fixed prosthesis. Material and methods Fifteen participants, either completely edentulous or with failing dentition in the maxillary arch and with severe atrophy of the posterior maxilla, were enrolled in the study. All participants underwent prosthodontic rehabilitation after implant placement in both the anterior maxilla areas and the pterygoid regions. The survival data of the implants were evaluated at the time of abutment connection by means of a mobility test for each implant. After placement of the prostheses, survival was assessed by means of marginal bone maintenance as assessed by panoramic radiographs and the absence of pain or symptoms of infection. The t test was used for evaluating the difference in age between men and women (α=.05). Correlations between categorical variables (Fisher exact test) were used to evaluate the possible association between the number of implants and both the age and presence of comorbidities (α=.05). Results During the 1-year follow-up, high prosthesis stability and no implant loss were observed for all participants. In addition, participants did not report any pain or paresthesia. No peri-implant radiolucency was detected in the panoramic radiographs. Survival and success rates in the follow-up period were 100%. Conclusions The present study supports the conclusion that pterygoid implants have a high success rate with minimal or no complications.

Systematic reviews showed possible esthetic complications with the use of traditional flap designs after guided bone regeneration (GBR) procedures in the esthetic zone and the aim of this case series was to analyze hard and soft tissue changes over 18 months after these procedures. Healthy subjects requiring tooth extraction and single-implant placement in the anterior maxilla were enrolled in the study. Three months after tooth extraction and ridge preservation, a prosthetic-driven implant was placed. The horizontal bone deficiency was treated with a resorbable bone graft substitute (beta tricalcium phosphate [β-TCP]) and a bioresorbable polylactic acid (PLA) membrane. Primary closure was obtained by a novel coronally advanced flap adapted from mucogingival techniques. Final metal-free implant restorations were delivered 4 months after placement. Clinical measurements, pictures, and radiographs were acquired after delivery of the final restoration (T1) and at the 18-month follow-up (T2). Digital impressions were taken at the time of tooth extraction (T-1) and implant insertion (baseline; T0) and at T2. Marginal bone level changes were assessed by radiographic analysis, while soft tissue changes were evaluated with ExoCad software. Student t test for paired data was used to detect differences between the different time points. Twelve subjects (7 men and 5 women; mean age: 63.7 ± 14 years) completed the study and received 15 implants. All implants healed uneventfully and were clinically osseointegrated and stable, showing no sign of infection. No GBR complications were noted. Statistically significant ridge-width changes were observed after extraction (T-1 vs T0 = -1.72 ± 0.30 mm; P = .00001) and after horizontal GBR (T0 vs T2 = 1.41 ± 0.64 mm; P = .00001). Radiographic bone levels after implant placement remained stable T0 to T2 (0.09 ± 0.08 mm). Periodontal parameters never exceeded physiologic levels. It can be concluded that GBR using a bioresorbable PLA membrane and resorbable β-TCP bone graft in conjunction with a coronally advanced flap is a predictable procedure for horizontal bone augmentation with simultaneous implant placement in the esthetic area.

We used Pulsed Laser Deposition (PLD) in oxidizing environment to epitaxially grow optimally doped manganite La2 / 3Sr1 / 3MnO3 (LSMO) thin films over a (001) oriented SrTiO3 substrate. Synthesized samples show good room temperature magnetic properties accompanied by a peculiar extension of the metallic conduction regime to temperatures higher than the Curie point. In this paper we present a study of the dependence of transport and magnetic properties of LSMO thin films on the oxygen pressure during PLD growth. We show how interaction of the growing films with O2 molecules is fundamental for a correct synthesis and in which way it is possible to adjust PLD experimental parameters in order to tune LSMO thin film properties. The persistence of the metallic conduction regime above the Curie temperature indicates some minor changes of the electronic structure near the Fermi level, which is responsible for the half-metallic behavior of LSMO at low temperature. This feature is rather intriguing from the technological point of view, as it could pave the way to the increase of operating temperature of devices based on LSMO.

We present a study of the local magnetic properties of an iron/iron oxide nanostructured granular system by X-ray magnetic circular dichroism. The samples investigated consist of metallic iron (alpha-Fe) nanoparticles embedded in a nanocrystalline oxide matrix composed by both magnetite (Fe3O4) and maghemite (gamma-Fe2O3). Samples were obtained by the inert gas condensation technique. Thanks to the chemical and site selectivity of XMCD, we were able to distinguish the magnetic contributions of the metallic core and of the two oxide phases present. in the matrix and independently study their behaviour as a function of iron particle size, applied magnetic field, sample temperature and magnetization history. (c) 2006 Elsevier B.V. All rights reserved.

Magnetic and magnetotransport measurements were performed on gas-phase synthesized Fe nanoparticles subjected to surface oxidation and cold consolidation. Two samples were investigated with α-Fe volume fraction of 0.15 and 0.60. The sample with smaller metallic fraction is below the percolation threshold for metallic conduction and the conduction mechanism is dominated by thermally activated processes across the oxide. In this case, by lowering the temperature, an increase of the negative magnetoresistance is observed up to 5% at 50 K in a magnetic field of 70 kOe. The magnetoresistance dependence on the sample magnetization, temperature and sample composition is discussed considering the magnetic correlations present in these nanostrucuterd systems.

This paper has evaluated the dental and or facial disorders associated to Goldblatt syndrome, also known as odontochondrodysplasia.We report the analysis performed on a female young patient affected by this disease. We analyzed her dental and or facial features.We adopted several diagnostic criteria: firstly, we performed radiographic investigations, followed by rhinomanometric measurements and by clinical analysis performed in order to determine the salivary flow in this typology of patients. The evidences obtained after a careful clinical, anamnestic, and radiographic analysis of our female patient allowed us to identify a number of odontostomatologic features, which are very likely to be related to this syndrome. Our patient showed some pathognomonic signs of odontochondrodysplasia already identified in the literature, that is, pectus carinatum, joint hyperextensibility, coxa valga and genu valgum, upper and lower limb asymmetry, and vertebral abnormalities. Moreover, we focused our attention on those odontostomatologic aspects that had never been analyzed by other reports in the literature: dentinogenesis imperfecta, ligamentous hyperlaxity of all joints and of temporomandibular joints in particular, poor lip competence, ogival palate, and oral respiration. Besides these, dental crowding and other important elements were identified through cephalometric measurements.In the light of all these elements and of their comparison with the existing literature, it is possible to stereotype a few recurrent odontostomatologic and systemic-generalized features in patients with odontochondrodysplasia, which can be considered as closely associated with this syndrome.

PURPOSE: To report the histological outcomes of a case of bilateral severely resorbed posterior maxilla augmented with the use of blocks of enzymatically deantigenated equine bone. MATERIALS AND METHODS: In conjunction with bilateral sinus lifts, blocks of enzymatically deantigenated equine bone were used bilaterally to augment the severely atrophic maxilla of a patient seeking a fixed implant-supported prosthesis. After 8 months, bone core samples were obtained from the augmentation sites and implants were placed. RESULTS: Six months after implant placement, the peri-implant bone levels were maintained. A prosthesis delivered 3 months after implant placement provided excellent rehabilitation. Histological analysis of the bone cores revealed that the graft material was still undergoing remodeling, with newly formed vital bone in all fields and osteoclasts included in the mineralized component. CONCLUSIONS: The deantigenated equine bone was biocompatible and resorbed only minimally. This material seems to offer excellent potential for being incorporated in a procedure that increases the width of edentulous alveolar crests.

We present a study of the local magnetic properties of iron/iron oxide granular nanostructures by x-ray magnetic circular dichroism (XMCD). Metallic iron $(\ensuremath{\alpha}\text{\ensuremath{-}}\mathrm{Fe})$ nanoparticles, with average sizes ranging from 5 to $13\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, are embedded in a nanocrystalline oxide matrix composed of both magnetite $({\mathrm{Fe}}_{3}{\mathrm{O}}_{4})$ and maghemite $(\ensuremath{\gamma}\text{\ensuremath{-}}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3})$. These granular samples were synthesized by cold compacting core-shell nanoparticles, in which a $2--3\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$-thick oxide layer surrounds the iron particles, synthesized by inert gas condensation. By exploiting the chemical selectivity and site sensitivity of XMCD, we were able to separate the magnetic contributions of the metallic core and of the two oxide phases present in the matrix and to study their behavior as a function of iron particle size and applied magnetic induction field. We detected the presence of a significant spin canting, predominantly affecting the octahedral sites of Fe in the oxide phase, and studied its dependence on the degree of structural disorder and applied magnetic induction field.

We report a detailed analysis of O K-edges near edge x-ray absorption of maghemite, hematite and magnetite iron oxides. Measurements were performed on powder in Fluorescence Yield mode of detection. Iron forms several stable oxides and its phase diagram is more complicated than that of other transition metal as Ni or Co. The differences in the local symmetry of the three iron oxides are related with the distinguishable NEXAFS spectra. In particular the spectra are characterized by a sharp doublet ascribable to transitions to the empty metal d-bands involving the t2g and eg states whose energy splitting and intensities depend on the structure and state of ionicity. The NEXAFS spectra have been simulated and fitted by MXAN code. The aim of these simulations was the test of light Z element NEXAFS spectra calculation performed by phenomenological no-self-consistent potential in the near edge region, the most sensible to electronic properties details; a fit procedure of the potential parameters was performed in the extended NEXAFS photon energy range and subsequently used for near edge calculations. The MXAN simulations obtained in this way, reproduce the experimental data with good agreement and evidentiate the differences in the spectra of the three compounds. In particular maghemite, that has oxygen in two different sites, has been well simulated using potential details found for the other oxides hematite and magnetite.

The exchange bias properties of a granular system composed of $\mathrm{Fe}$ nanoparticles (mean size $\ensuremath{\sim}6\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$) embedded in an $\mathrm{Fe}$ oxide matrix have been studied. The effect of the cooling field on the exchange field, coercivity and remanent magnetization at $T=5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$ has been investigated. The observed variations are explained in terms of interfacial exchange coupling between a ferromagnetic phase (the $\mathrm{Fe}$ particles) and a disordered magnetic phase (the oxide matrix), whose spin configuration is strongly affected by the cooling field.

We report a detailed morphological and structural characterization of iron/iron oxide core-shell nanoparticles with x-ray diffraction and x-ray absorption spectroscopy performed at both the Fe and O $K$ edges. Core-shell nanoparticles with core size ranging from 7 to 21 nm were synthesized using the inert gas condensation technique followed by 12 h of controlled surface oxidation. Rietveld analysis of diffraction patterns shows the presence of \ensuremath{\alpha}-Fe nanoparticles surrounded by a 2--3 nm-thick oxide layer with a disordered cubic spinel structure. Magnetite $({\mathrm{Fe}}_{3}{\mathrm{O}}_{4})$ and maghemite $(\ensuremath{\gamma}\ensuremath{-}{\mathrm{Fe}}_{2}{\mathrm{O}}_{3}),$ two different iron oxides, share this lattice structure, but x-ray diffraction was not able to distinguish between the two. An analysis of the Fe and O x-ray absorption spectra in both the near-edge and the extended energy regions is described. The analysis of the extended spectra was performed using the ab initio calculation of all significant contributions to the absorption cross section. We show that there are size-dependent changes in the local structure and oxidation state of the oxide shell, the relative fraction of maghemite increasing at the expense of magnetite as the core dimensions decrease. This size/structure correlation has been explained in terms of morphological and structural disorder arguments

Different surgical treatment strategies for peri-implantitis with the use of graft material and membranes have been suggested without any longitudinal remarkable success rate. The present preliminary study was aimed to analyze a new clinical approach based on the disinfection of the implant connection, the disinfection of the implant surface and GBR approach in the treatment of circumferential and semi-circumferential bony defect resulting from peri-implantitis. Six consecutive patients were selected for the present study. After removal of factors that could potentially influence peri-implant pathology, the prosthetic rehabilitation was always removed and a full thickness flap was elevated to allow access to the peri-implant defect and the exposed implant surface. Once the defect was degranulated and the implant surface cleaned, a mixture (50:50) of autogenous bone and allograft was used. Guided bone regeneration technique using membranes was adopted and the flaps were closed for a submerged healing. Six months thereafter, a new re-opening procedure was performed and cleaned superstructures and crowns were repositioned. Patients were followed for one year thereafter and recalled for a customized oral hygiene every three months. Radiological and periodontal analysis was performed before surgery and every six months. The studied procedure was associated with a pronounced increase in REC and CAL with stable peri-implant conditions at 6 and 12 months. PI, BOP and PD values were significantly reduced both at 6 and 12 months. At 12 months, a mean PD gain of 4.5 mm and a bone loss reduction of 5.1 mm was obtained. Within the limitation of the present preliminary study, the proposed technique might represent a promising result for treatment of circumferential and semi-circumferential bone defects around implants affected by peri-implantitis.