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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 management of patients under treatment with Direct Oral Anticoagulants (DOACs) has led clinicians to deal with two clinical issues, such as the hemorrhagic risk in case of non-interruption or the risk of thromboembolism in case of suspension of the treatment. The primary aim of this retrospective study was to evaluate the incidence of perioperative bleeding events and healing complications in patients who were under treatment with Rivaroxaban and who received dental implants and immediate prosthetic restoration. Patients treated with Rivaroxaban (Xarelto 20 mg daily) and who needed implant rehabilitation were selected. Four to six implants were placed in mandibular healed sites or fresh extraction sockets. All patients, in agreement with their physicians, interrupted the medication for 24 h and received implants and immediate restorations. Twelve patients and 57 implants were analyzed in the study. No major postoperative bleeding events were reported. Three patients (25%) presented slight immediate postoperative bleeding controlled with compression only. The implant and prosthetic survival rate were both 100% after 1 year. Within the limitations of this study, multiple implant placement with an immediate loading can be performed without any significant complication with a 24 h discontinuation of Rivaroxaban, in conjunction with the patient&rsquo, s physician.

A gas chromatography/mass spectrometry (GC/MS) method for determination of nine N-nitrosamines (NAs) in water is described. Two ionization modes, electron impact (EI) and chemical ionization (CI) with methanol, as well as different ion analysis techniques, i.e. full scan, selected ion storage (SIS) and tandem mass spectrometry (MS/MS) were tested. Chemical ionization followed by SIS resulted the mass spectrometric method of choice, with detection limits in the range of 1–2 ng/L. Solid Phase Extraction (SPE) with coconut charcoal cartridges was applied to extract NAs from real samples, according EPA Method 521. Drinking water samples were collected from seven surface- and two groundwater treatment plants. Three surface water treatment plants were sampled before and after addition of O 3 /ClO 2 to observe the effect of disinfection on NAs’ formation. N-nitrosodiethylamine (NDEA), n-nitrosodipropylamine (NDPA), n-nitrosomorpholine (NMOR) and n-nitrosodibutylamine (NDBA) were found up to concentrations exceeding three times the risk level of 10 ng/L set by the California Department of Public Health. Because dermal adsorption has been recently indicated as a new contamination route of exposure to NAs for people who practice swimming activity, water samples from five swimming pools in the Bologna (Italy) area were collected. N-nitrosopyrrolidine (NPYR) was detected in all samples at concentrations larger than 50 ng/L, likely as a disinfection by-product from the amino acid precursor proline, a main constituent of skin collagen.

The aim of this work is expanding the base of data on which a previous developed method of predicting polyethylene (PE) quality was based. The refined method will provide water companies with a simple way of assessing chemical differences that may occur among PE pipes due to different manufacturers or different batches of virgin polymer. A number of samples, taken from PE water-ducts, were pyrolysed (triplicate analyses) at 700 °C in N 2 atmosphere using a platinum coil pyrolyser inside a tube cooled in liquid nitrogen. The volatile and non-volatile products were identified and quantified by gas chromatography/mass spectrometry, and subjected to discriminant analysis. The same samples were also pyrolysed at 900 °C in order to analyse high molecular weight pyrolysis products. Moreover, polycyclic aromatic hydrocarbons and volatile organic compounds leaching from PE tubes into drinking water were determined. Data acquired were matched up with results obtained using physical methods of polymer characterisation, namely density, oxidative induction time, melt flow rate and carbon black dispersion.

Females of the pine sawfly Neodiprion sertifer (Hymenoptera Diprionidae) usually avoid Pinus pinea trees as host plants. In contrast, this sawfly species is highly attracted by P. sylvestris and P. nigra trees. Here, we investigated which pine volatiles might mediate this behavior by in situ sampling experiments and olfactometer laboratory tests. Volatiles emitted from P. pinea, P. sylvestris, and P. nigra foliage were sampled by solid-phase microextraction (SPME). Analysis of these volatiles by coupled gaschromatography/ mass spectrometry revealed that the relative amounts of the compounds emitted by the three species were significantly different. A discriminant analysis showed that the amounts of limonene and myrcene significantly contributed to the species-specific volatile patterns. Pinus pinea emitted higher relative amounts of limonene than the other pine species. Pinus sylvestris emitted the highest relative amounts of myrcene. When testing the response of N. sertifer females to these pine terpenoids in an olfactometer bioassay, a low amount of limonene was attractive, while a repellent effect was evident when higher amounts were used. The sawfly females showed no significant olfactory response to myrcene. These data suggest that low relative amounts of limonene have a significant function in attracting N. sertifer females, while high amounts might contribute to avoidance of a tree.

A solid-phase microextraction (SPME) method was developed for air monitoring of organic solvents frequently used in chemical laboratories (namely pentane, dimethyl ether, acetone, acetonitrile, dichloromethane, hexane, ethylacetate, tetrahydrofurane, cyclohexane, benzene, and toluene). SPME sampling conditions and chromatographic separation were optimised. Linearity of response for each component of the mixture was tested. Standard solutions containing all the compounds, at three different concentrations, were analysed in triplicate and the relative standard deviations (RSDs) were calculated. The method was applied to the monitoring of indoor air in a research chemical laboratory. An SPME fibre was used as a sampling device inside the laboratory. Moreover an SPME fibre was used as a portable sampling device in order to determine the effective human exposure. Comparison of the portable and fixed sampling device showed differences in the amount of solvents associated with activities performed nearby.

During one of Coronelli's terrestrial globes restoration, belonging to the Bologna University, we found some substances considered not to be original. Their presence was both on the globe surface and under one of the gores. In order to characterise the organic material (original or added in restoring procedures) we employed pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The analytical results reveal the presence of the original materials, such as natural gums and animal glues, together with industrial products, such as synthetic germicides.

This text is the first detailed account of the application of new and established mass spectrometric techniques utilizing trapped or confined ions for prolonged investigation and increased sensitivity. Each chapter contains complete references and utilizes a consistent format and writing style, with all terms, acronyms, procedures, and equations thoroughly explained. The strong editorial input to the diverse sections enables readers to readily appreciate the commonalities of topics ranging from theory of instrument operation to proteins, flavonoids, atomic clocks, and single ion mass spectrometry. This chapter deals with the monitoring Volatile Organic Compouns (VOCs) in water samples. VOCs are a very important class of water pollutants because of their persistence and suspect carcinogenicity for many of them. There are about sixty VOCs, including benzene, toluene, ethylbenzene, and xylenes (BTEX), halomethanes, haloethanes. A real-time, on-line, continuous monitoring of such compounds would allow prompt actions in order to avoid the diffusion of pollutants in the water system or to take appropriate countermeasures, thus restoring safe conditions in case of accidental contamination. Membrane Inlet Mass Spectrometry (MIMS) has been extensively studied for the determination of VOCs in various environmental matrices, especially water and air samples. MIMS allows the introduction of VOCs in the mass spectrometer through a thin (some tenths of millimeter) hollow-fiber polymeric membrane, which is selective towards organic compounds. When the membrane is in contact with the sample and an ion trap mass spectrometer is used as detector, such as in the present instance, VOCs are extracted in the membrane, concentrated in its small volume, and swept into the mass spectrometer by a gentle stream of helium carrier gas. The whole process is called pervaporation. When the membrane is exposed to a sample containing the target compounds, and the ions characteristic of each target compound are detected by mass spectrometry, the inherent ion current increases up to reaching a plateau. In brief, the characteristic ions are the qualitative information which allows identification of the analytes, while the plateau height is the quantitative information, with sensitivity in the sub-ppb levels and dynamic range of up to four decades for many VOCs. Although many papers have demonstrated that MIMS is a potentially excellent technique for continuous VOC monitoring given its simplicity and sensitivity, as to our knowledge no experiment has been published to check whether MIMS can be really implemented in a device able to work unattended for months. The present chapter reports on laboratory and field tests of MIMS instruments built in our laboratory as to hardware and software. Four instruments were deployed in unmanned sites, where they monitored VOCs in natural- and waste waters during a period exceeding 1 year/instrument. Laboratory performance – in terms of sensitivity, reproducibility, linearity tests, and comparison with P&T/GC/MS – and field performance – in terms of data output, most frequent maintenance operations and technical failures, and overall stability of the four remotely controlled instruments will be discussed.