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Objectives: The aim of the present study was to evaluate the cutting efficiency of two new reciprocating instruments, Twisted File Adaptive and WaveOne Primary., Material and Methods: 10 new Twisted File Adaptive (TF Adaptive) (SybronEndo, Glendora, CA, USA) and 10 new WaveOne Primary files (Dentsply Maillefer, Ballaigues, Switzerland) were activated using a torque-controlled motor, respectively TFA motor (SybronEndo, Glendora, CA, USA) and Silver motor (VDW, Munich, Germany). The device used for the cutting test consisted on a mainframe to which a mobile plastic support for the hand-piece is connected and a stainless-steel block containing a Plexiglas block against which the cutting efficiency of the instruments was tested. The length of the block cut in 1 minute was measured in a computerized program with a precision of 0.1 mm. Mean and standard deviations of each group were calculated and data were statistically analyzed with one-way ANOVA and Bonferroni t test (P < 0.05)., Results: TF Adaptive displayed significantly greater maximum penetration depth than WaveOne Primary (P < 0.05). In fact, TF Adaptive instruments (Group 1) cut the Plexiglas block to a mean depth of 8.7 (SD 0.5) mm, while WaveOne Primary instruments cut the Plexiglas block to a mean depth of 6.4 (SD 0.3) mm., Conclusions: Twisted File Adaptive instruments demonstrated statistically higher cutting efficiency than WaveOne instruments.

Purpose: The purpose of this study was to compare bone temperature changes during implant drilling with two drill designs employed in three different drilling sequences., Materials and Methods: Two implant drill designs and three drilling sequences were evaluated in vitro using artificial bone cylinders. The evaluated drills were different only in the cutting-surface length (control, 16 mm; test, 4 mm). Three drilling sequences (control A, test B1, and test B2) were evaluated with and without irrigation. Temperatures were measured with thermocouple technology. The temperature changes generated by the final drill of each sequence were recorded as the experimental results and were subjected to the Student t test., Results: There were statistically significant differences in temperature changes when comparing the control group A with the test groups B1 (P = .001) and B2 (P = .01) during drilling without coolant. The mean temperature changes were 12.4°C, 6.5°C, and 13.7°C for groups A, B1, and B2, respectively. The Student t test showed statistically significant differences between temperature changes of the control group A and the test groups B1 (P < .01) and B2 (P < .05) during drilling with coolant. The mean temperature changes were 0.9°C, 0.7°C, and 1.9°C for groups A, B1, and B2, respectively., Conclusion: Reduction in length of the cutting surface of the drill may limit frictional heat. Drills with the same length of cutting surface may induce lower bone temperature changes, when considering a preliminary drilling step with a pilot drill.

Falls represent one of the most common causes of injury-related morbidity and mortality in later life. Subjects with cardiovascular disorders (e.g., related to autonomic dysfunctions and postural hypotension) are at higher risk of falling. Autonomic dysfunctions increasing the risk of falling in the short and mid-term could be assessed by Heart Rate Variability (HRV) extracted by electrocardiograph (ECG). We developed three trials for assessing the usefulness of ECG monitoring using wearable devices for: risk assessment of falling in the next few weeks; prevention of imminent falls due to standing hypotension; and fall detection. Statistical and data-mining methods are adopted to develop classification and regression models, validated with the cross-validation approach. The first classifier based on HRV features enabled to identify future fallers among hypertensive patients with an accuracy of 72% (sensitivity: 51.1%, specificity: 80.2%). The regression model to predict falls due to orthostatic dropdown from HRV recorded before standing achieved an overall accuracy of 80% (sensitivity: 92%, specificity: 90%). Finally, the classifier to detect simulated falls using ECG achieved an accuracy of 77.3% (sensitivity: 81.8%, specificity: 72.7%). The evidence from these three studies showed that ECG monitoring and processing could achieve satisfactory performances compared to other system for risk assessment, fall prevention and detection. This is interesting as differently from other technologies actually employed to prevent falls, ECG is recommended for many other pathologies of later life and is more accepted by senior citizens.

Endodontic glide path is the creation of a smooth patency from canal orifice to apex, which can be performed manually or with small tapered NiTi rotary instruments. The use of stainless steel (SS) hand K-files inserted in a reciprocating handpiece can be a possible alternative to create a mechanical glide path. The aim of this study was to compare the cyclic fatigue resistance between SS K-files used in a reciprocating motion and NiTi rotary instruments in artificial curved canals. Ten SS size 15 K-files used with the M4 handpiece (SybronEndo, Glendora, CA, USA) and ten PathFiles (Maillefer-Dentsply, Ballaigues, CH, Switzerland) NiTi rotary instruments size 16, 0.02 taper were tested for resistance to cyclic fatigue. The time to fracture inside an artificial curved canal was recorded for each instrument. Data were analyzed by one-way ANOVA and Tukey HSD test. Mean time (and SD) to failure was 464 s (±40.4) for the Group PF (NiTi rotary PathFile), and 1049 s (±24.8) for the Group M4 (SS K-files reciprocating) with a statistically significant difference between the two groups (p = 0.033). The SS 15 K-files used with the M4 handpiece showed a significant greater resistance to cyclic fatigue when compared to the NiTi rotary PathFiles. Therefore, the use of small size SS files in a reciprocating motion might be a rational choice for the creation of a mechanical endodontic glide path in curved root canals.

Objective: Acute stress provides many beneficial effects whereas chronic stress contributes to a variety of human health issues including anxiety, depression, gastrointestinal problems, cardiac disease, sleep disorders and obesity. The goal of this work was to identify, using a rodent model, hippocampal gene signatures associated with prolonged chronic stress representing candidate biomarkers and therapeutic targets for early diagnosis and pharmacological intervention for stress induced disease., Materials & Methods: Mice underwent 'restraint stress' over 7 consecutive days and hippocampal gene-expression changes were analyzed at 3, 12 and 24 h following the final restraint treatment., Results: Data indicated that mice exposed to chronic restraint stress exhibit a differential gene-expression profile compared with non-stressed controls. The greatest differences were observed 12 and 24 h following the final stress test., Conclusion: Our study indicated that Gpr88, Ttr, Gh and Tac1 mRNAs were modulated in mice exposed to chronic restraint stress. These transcripts represent a panel of biomarkers and druggable targets for further analysis in the context of chronic stress associated disease in humans.

Detection and real time monitoring of obstructive sleep apnea (OSA) episodes are very important tasks in healthcare. To suitably face them, this paper proposes an easy-to-use, cheap mobile-based approach relying on three steps. First, single-channel ECG data from a patient are collected by a wearable sensor and are recorded on a mobile device. Second, the automatic extraction of knowledge about that patient takes place offline, and a set of IF…THEN rules containing heart-rate variability (HRV) parameters is achieved. Third, these rules are used in our real-time mobile monitoring system: the same wearable sensor collects the single-channel ECG data and sends them to the same mobile device, which now processes those data online to compute HRV-related parameter values. If these values activate one of the rules found for that patient, an alarm is immediately produced. This approach has been tested on a literature database with 35 OSA patients. A comparison against five well-known classifiers has been carried out.

Real-time Obstructive Sleep Apnea (OSA) episode detection and monitoring are important for society in terms of an improvement in the health of the general population and of a reduction in mortality and healthcare costs. Currently, to diagnose OSA patients undergo PolySomnoGraphy (PSG), a complicated and invasive test to be performed in a specialized center involving many sensors and wires. Accordingly, each patient is required to stay in the same position throughout the duration of one night, thus restricting their movements. This paper proposes an easy, cheap, and portable approach for the monitoring of patients with OSA, which collects single-channel ElectroCardioGram (ECG) data only. It is easy to perform from the patient's point of view because only one wearable sensor is required, so the patient is not restricted to keeping the same position all night long, and the detection and monitoring can be carried out in any place through the use of a mobile device. Our approach is based on the automatic extraction, from a database containing information about the monitored patient, of explicit knowledge in the form of a set of IF…THEN rules containing typical parameters derived from Heart Rate Variability (HRV) analysis. The extraction is carried out off-line by means of a Differential Evolution algorithm. This set of rules can then be exploited in the real-time mobile monitoring system developed at our Laboratory: the ECG data is gathered by a wearable sensor and sent to a mobile device, where it is processed in real time. Subsequently, HRV-related parameters are computed from this data, and, if their values activate some of the rules describing the occurrence of OSA, an alarm is automatically produced. This approach has been tested on a well-known literature database of OSA patients. The numerical results show its effectiveness in terms of accuracy, sensitivity, and specificity, and the achieved sets of rules evidence the user-friendliness of the approach. Furthermore, the method is compared against other well known classifiers, and its discrimination ability is shown to be higher., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Objective: The objective of this study was to investigate the effects of rosiglitazone (Avandia(®)) on gene expression in neonatal rat ventricular myocytes., Materials & Methods: Myocytes were exposed to rosiglitazone ex vivo. The two factors examined in the experiment were drug exposure (rosiglitazone and dimethyl sulfoxide vs dimethyl sulfoxide), and length of exposure to drug (½ h, 1 h, 2 h, 4 h, 6 h, 8 h, 12 h, 18 h, 24 h, 36 h and 48 h)., Results: Transcripts that were consistently expressed in response to the drug were identified. Cardiovascular system development, extracellular matrix and immune response are represented prominently among the significantly modified gene ontology terms., Conclusion: Hmgcs2, Angptl4, Cpt1a, Cyp1b1, Ech1 and Nqo1 mRNAs were strongly upregulated in cells exposed to rosiglitazone. Enrichment of transcripts involved in cardiac muscle cell differentiation and the extracellular matrix provides a panel of biomarkers for further analysis in the context of adverse cardiac outcomes in humans. Original submitted 15 November 2013; Revision submitted 14 February 2014.

This work investigated the antibacterial activity of 14 bonding agents to predict their ability to inhibit white-spot development during orthodontic treatment. Standardized, sterilized disks of each material were continuously rinsed (for up to 180 d) in a flow of sterile saline. At predetermined time points, the residual ability of each material to inhibit bacterial growth (determined by measuring the size of inhibition halos around disks placed onto appropriate culture media seeded with Streptococcus gordonii DSM6777, Streptococcus sanguinis DSM20567, Streptococcus mutans DSM20523, or Lactobacillus acidophilus DSM20079) and biofilm formation (determined by measuring the numbers of bacteria adherent to disks following incubation in appropriate broths) was tested in triplicate and compared with the baseline activities of freshly prepared materials. Overall antibacterial and anti-biofilm activities, adjusted for exposure time and strain of bacteria, were assessed. The decrease of antibacterial activity was faster (30-60 d) and complete for fluoride-enriched materials, but slower (90 d) and partial for antimicrobial-containing materials (benzalkonium chloride, zinc oxide, chlorexidine, or MDPB). Materials enriched with benzalkonium chloride, chlorexidine, or MDPB showed the highest antibacterial activities. Anti-biofilm assays yielded similar results. These data could be helpful for clinicians in the choice of the best performing bonding agent also in light of duration of the clinical application., (© 2014 Eur J Oral Sci.)

Aim: The manual files are still widely used for initial canal negotiation prior the use of nickel-titanium shaping instruments, to determine working length and to verify patency. A mechanical glide path can be performed using manual files with handpieces, such as M4 Handpiece (SybronEndo, USA) that allows a 30°/30° reciprocating motion. The Pathfinders (SybronEndo, USA) are hand files designed to negotiate complex canals, made from stainless steel (SS) or carbon steel (CS) alloys. The aim of this in vitro study was to compare cyclic fatigue resistance of these two different types of manual Pathfinder instruments used in a M4 reciprocating handpiece in double curved artificial canals., Materials and Methods: Manual instruments designed for glide path (size #9 ISO .02 taper) made from different alloys were selected: Group SS -stainless steel Pathfinders (Sybron Endo) and Group CS - carbon steel Pathfinders size K2 (Sybron Endo). Ten instruments of each group were tested for resistance to cyclic fatigue with a reciprocating M4 handpiece inside an artificial S-shaped canal; the time to fracture was recorded for each file and data were statistically analyzed (ANOVA)., Results: Mean values (and SD) were 527 (± 89) seconds for the CS instruments and 548 (± 104) seconds for the SS files. No significant differences were observed between groups (p=0,062)., Conclusions: According to the results, both carbon and stainless steel instruments presented similar fatigue resistance when used with M4 reciprocating handpiece in double curved canals.

Patient context awareness is an important concept for application services in mHealth environments. In this paper we present a multi-sensors system that uses a rule-based DSS able to enhance the accuracy of potentially dangerous heart rate variability by taking into account patient context information. In addition the proposed system is able to detect also patient falls in real time. We have designed and implemented an intelligent, user-friendly, and context-aware system that allows receiving data from several sensors and provides the computational power for context recognition. We also show that the use of an intelligent approach relying on a rule-based DSS for the analysis of data and vital signs is better than approaches missing either DSS or context-awareness. Finally, the paper also describes a case study where the system has revealed important benefits for both patients and medical staff.

The objective of this paper is to assess the role of conventional and high-frequency ultrasound in the evaluation of the depth of cutaneous skin cancer. The study was performed on 46 subjects, divided into 3 categories, according to their skin pathology [basal cell carcinoma (BCC), 18 subjects; superficial spreading melanoma (SSM), 8 subjects; nodular melanoma (NM), 20 subjects]. Conventional and high-frequency ultrasonographic measurements were performed in order to assess the thickness of the tumors and the vascularization degree. We compared the mean values of the tumoral thickness obtained by using ultrasound (ultrasonographic depth index) with the histological depth index, obtained after performing histological sections stained with hematoxylin-eosin, and specific monoclonal antibodies in case of pigmented tumors. We established a correlation index between the histological and ultrasonographic values of the tumoral thickness. We found a strong correlation between the ultrasonographic index (measured by high-frequency sonography) and the histological index for nodular BCC (correlation of 98.4 %), NM subjects (correlation of 98.4 %), and SSM subjects (correlation of 99.4 %). An increase of the blood supply was noticed in nodular lesions only. Ultrasonography allows a very accurate assessment of skin cancer. The ultrasonographic depth index can be considered an objective, non-invasive marker for cutaneous tumors, comparable to the histological one, with a very good sensitivity (98-99 %).

Aim: The aim of the present study was to compare the resistance to cyclic fatigue of Hyflex® (Coltene-Whaledent, Allstatten, Switzerland) size 40 taper.04 nickel titanium instruments used in continuous rotation versus the use with a reciprocating motion. The null hypothesis was that different file motions had no influence on the lifetime of instruments subjected to a cyclic fatigue test., Methodology: 24 Hyflex® size 40 taper.04 nickel titanium instruments were randomly divided in two groups (n=12 each), and submitted to a cyclic fatigue test. The first group (CR group) were used with a continuous rotation, while the second one (RCP group) with a reciprocating motion. The cyclic fatigue tests were performed by using a stainless steel block containing an artificial canal shaped with a 135° angle. All instruments were rotated or reciprocated until fracture occurred. The time to fracture was recorded visually with a 1/100 second chronometer. Data were recorded and statistically analysed., Results: Results indicated that instruments used with a reciprocating motion showed a significant increase in the meantime to failure when compared to those used in continuous rotation., Conclusions: The null hypothesis was rejected. Results of the present study showed that reciprocating motion extended resistance to cyclic fatigue of the tested nickel titanium instruments, when compared to continuous rotation.

Aims: Apical extrusion of infected debris to the periradicular tissues is one of the principal causes of postoperative pain and discomfort. Recent researches have shown that reciprocating instrumentation techniques seem to significantly increase the amount of debris extruded beyond the apex and, consequently, the risk of postoperative pain. The goal of the present study was to evaluate and compare postoperative pain using three different nickel-titanium instrumentation techniques: a rotary crown-down technique using TF instruments (SybronEndo, Orange, Ca), a reciprocating single-file technique using WaveOne instruments (Maillefer DEntsply, Baillagues, CH), and a novel instrumentation technique (TF Adaptive, SybronEndo, Orange, Ca), using a unique, proprietary movement, combining reciprocation and continuous rotation., Methods: Ninety patients requiring endodontic treatment on permanent premolar and molar teeth with non vital pulps preoperatively were included in the study. The patients were assigned into three groups of 30 patients each, trying to make the groups very similar, concerning the number of root canals, presence of initial pain and periapical lesions. The teeth in group 1 (n = 30) were instrumented with a crown-down technique using TF instruments, whilst those in group 2 (n = 30) were instrumented with a single-file technique using Waveone 08 25. The third group (n = 30) used the 3-file Tf Adaprtive sequence. All techniques were performed following manufacturers' instructions and all canals were shaped, cleaned and obturated in a single-visit by the same operator. The assessment of postoperative pain was carried out at 3 days by using a visual analogue scale. VAS pain scores were compared using one-way ANOVA post hoc Tukey test. A value of p < 0.05 was required for statistical significance., Results: Results for VAS pain scores showed a statistically significant difference was found between the WaveOne (p=0,021) technique and the other two techniques. No statistical significant differences were found between TF and TF Adaptive (p= 0,087). When evaluating patient experiencing sever pain the incidence of symptoms was significantly higher with the WaveOne technique., Conclusions: Since the incidence of preoperative pain, the type of tooth and the pulp and periodontal pathology were quite similar between the three tested groups, and all the other variables (operator, irrigation, obturation) were identical, we may conclude that the difference in postoperative pain can be mainly related to the different instrumentation techniques.

Purpose: To evaluate the mechanical properties and behavior of a self-locking taper connection with three different techniques: three-dimensional finite element analysis (FEA), ultimate failure loading, and cyclic loading analysis., Materials and Methods: The implant-abutment complex was embedded vertically in the center of an acrylic resin support block (Young's modulus > 3 GPa). All materials used in this study were assumed to be homogenous and isotropic, but while the resin was assumed to be linearly elastic, the titanium was assumed to have a multilinear behavior to better represent the implant system in its plastic phase and to compare as closely as possible the numeric simulation with the experimental tests. An 800-N 30-degree off-axis load was applied to the occlusal surface of the abutment. In addition to the FEA, static and dynamic tests were carried out., Results: The greatest von Mises stresses were concentrated in the coronal portion of the abutment's tapered connection, while at the implant neck they were lower and less extensive than the abutment ones. Experimental results confirmed the FEA findings, in which the structural limit of the system was reached, with permanent deformation of the abutment that exceeded a predefined limit, rather than fracture., Conclusion: Within the limitations of the reported analyses, these static and dynamic tests appear to supply congruent results, thus allowing evaluation of the mechanical behavior of a self-locking tapered-connection implant system. High resistance to an off-axis load was exhibited, exceeding that usually offered by screw-retained implant systems, thus indicating good stability of the implant-abutment connection.

The geometry of some medical images of tissues, obtained by elastography and ultrasonography, is characterized in terms of complexity parameters such as the fractal dimension (FD). It is well known that in any image there are very subtle details that are not easily detectable by the human eye. However, in many cases like medical imaging diagnosis, these details are very important since they might contain some hidden information about the possible existence of certain pathological lesions like tissue degeneration, inflammation, or tumors. Therefore, an automatic method of analysis could be an expedient tool for physicians to give a faultless diagnosis. The fractal analysis is of great importance in relation to a quantitative evaluation of "real-time" elastography, a procedure considered to be operator dependent in the current clinical practice. Mathematical analysis reveals significant discrepancies among normal and pathological image patterns. The main objective of our work is to demonstrate the clinical utility of this procedure on an ultrasound image corresponding to a submandibular diffuse pathology.

This study aimed to investigate the influence of implant design (in terms of diameter, length, and thread shape), in-bone positioning depth, and bone posthealing crestal morphology on load transfer mechanisms of osseointegrated dental implants based on platform-switching concept. In order to perform an effective multiparametric comparative analysis, 11 implants different in dimensions and in thread features were analyzed by a linearly elastic 3-dimensional finite element approach, under a static load. Implant models were integrated with the detailed model of a maxillary premolar bone segment. Different implant in-bone positioning levels were modeled, considering also different posthealing crestal bone morphologies. Bone overloading risk was quantified by introducing proper local stress measures, highlighting that implant diameter is a more effective design parameter than the implant length, as well as that thread shape and thread details can significantly affect stresses at peri-implant bone, especially for short implants. Numerical simulations revealed that the optimal in-bone positioning depth results from the balance of 2 counteracting effects: cratering phenomena and bone apposition induced by platform-switching configuration. Proposed results contribute to identify the mutual influence of a number of factors affecting the bone-implant loading transfer mechanisms, furnishing useful insights and indications for choosing and/or designing threaded osseointegrated implants.

Statement of Problem: In the posterior maxilla, tooth loss is usually associated with alveolar bone resorption and sinus pneumatization, limiting the placement of implants without grafting procedures., Purpose: The purpose of this study was to evaluate a minimally invasive treatment of the atrophic posterior maxilla, with axial and tilted implants and immediate loading. The research hypothesis was that the combination of a guided, minimally invasive approach and the biomimetic features of computer-aided design and computer-aided manufacturing (CAD/CAM) abutments would be an effective alternative to maxillary sinus floor augmentation procedures with reduced bone resorption around implants., Material and Methods: Twenty-seven consecutive participants (female=12, male=15) (mean age 54.18 years) with severe atrophy of the posterior maxilla were treated by using guided surgery with immediately loaded axial (39) and tilted (42) implants supporting CAD/CAM zirconia (39) and titanium (42) abutments (81 total) and partial fixed prostheses. Each participant underwent a computed tomography scan, after which 2 or 3 implants were positioned with a flapless or miniflap approach. The drilling protocol was adapted to the bone density of each implant site to obtain an insertion torque ranging between 40 and 50 Ncm. CAD/CAM customized abutments composed of zirconia or titanium were fixed to the implants with prosthetic screws tightened with a torque of 35 Ncm. An acrylic resin interim restoration reinforced with metal was placed immediately. Five to 6 months after initial loading, a zirconia framework was manufactured, and a definitive prosthesis was placed. Clinical and radiological controls were performed at baseline and after 1 and 3 years to assess implant and prosthesis survival and success rate and compare marginal bone remodeling of axial and tilted implants. Inferential statistics for radiological data were acquired by using the Mann-Whitney U-test. All statistical comparisons were conducted at the .05 significance level., Results: The mean follow-up period was 43.3 months (ranging from 36 months to 54 months). The cumulative implant survival rate was 96.3% at 3 years. All prosthetic restorations were stable and in good function, resulting in a cumulative prosthetic survival rate of 100%. Three restorations had chipping of the veneer material; thereafter, the cumulative prosthetic success rate was 91.9%., Conclusions: Treatment of the posterior partially edentulous atrophic maxilla with guided surgery and immediate loading of tilted and straight implants supporting short-span partial fixed dental prostheses is effective., (Copyright © 2012 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.)

Purpose: The purpose of this study was to investigate, by finite element analysis (FEA) and fatigue analysis, the influence of different loading conditions on the stress distribution in a 3-unit implant-supported Y-TZP fixed partial denture (FPD)., Material and Methods: A three-dimensional FEM model was developed. The materials used in this study were assumed to be linearly elastic, homogeneous and isotropic. 100 N and 300 N loads over a 0,5 mm(2) areas with different angles (0°, 15° and 35°) and locations were applied on the prosthesis and the distribution of equivalent von Mises stress was investigated. A fatigue analysis was carried out too., Results: Maximum stresses were found at the connector region of the framework when the intermediate element is loaded (100 N load pattern: 32,9 MPa, 33 MPa and 51,8 MPa; 300 N load pattern: 98,6 MPa, 102,8 MPa and 155,7 MPa, respectively with 0°, 15° and 35° of inclination). Results confirmed the vulnerability of both connector areas even if just one pillar was loaded with an increase in stress when angle of load inclination is larger. The cyclic fatigue evaluation indicates a strong propensity for fatigue behavior, presenting a considerable range of loading conditions. No fracture fatigue occurred with a 100 N force. A 300 N force applied to the pontic produces no fatigue problems because the load is equally shared by whole system. A 300 N force applied to one of the two pillars, or to both implants generates fatigue problems., Conclusion: F.E.M. analysis of a 3-unit implant-supported Y-TZPFPD, give accurate information about loading conditions for clinical success over time. Fatigue analysis results show structural reliability of the Y-TZP as framework material for 3-unit posterior FPDs.

The prevalence of the elderly population, as well as life expectancy, increased in the final decades of the 20th century, as described in the World Health Organization 2004 Annual Report. The edentulous condition therefore has a negative impact on the oral health-related quality of life. Patients wearing complete dentures for many years infact, and especially in the mandible, are often unsatisfied because of the instability of the prosthesis during speaking and eating. To date dental implant treatment is well documented as a predictable treatment for partial or complete edentulism. On the other hand the rehabilitation of atrophied edentulous arches with endosseous implants (> 10 mm) in the posterior regions is often associated with anatomic problems such as bone resorption, poor bone quality, mandibular canal, and the presence of maxillary sinuses. Different procedures have been proposed to overcome these anatomic limitations. The use of tilted implants parallel to the anterior wall of the maxillary sinus or the mental foramen/inferior alveolar nerve has been proposed as a conservative solution for the treatment of the atrophic edentulous maxilla. Aim of this study was to describe, through a detailed literature review, the clinical and biomechanical rationale for tilting implants and to evaluate the long-term prognosis of immediately loaded full fixed prostheses for the treatment of edentulous patients (#35) with extreme bone atrophy rehabilited with both axial (#70) and tilted (#70) implants from 2008 to 2010. The results of the present study would suggest that this new surgical technique may reduce patient morbidity and extend the indications for immediate loading full fixed rehabilitations. This improves the predictability of treatment goal, allows for a better risk management, and provides more individual information for the patient. These are the most important aspects of this technology, which may contribute to establish higher-quality standards in implantology.

Purposes: The aim of the study was to assess by means a 3D finite element linear and non-linear analysis mechanical interaction between an implant-supported crown and surrounding tissues., Materials and Methods: A three-dimensional FEM model was developed. Four different material combinations for the abutment and the core were evaluated: Y-TZP - Y-TZP, Y-TZP - microhybrid composite, T - microhybrid composite; T and Y-TZP. 250 N and 450 N loads over a 0,5 mm(2) areas with different angles (0° and 45°) and locations were applied on the occlusal surface of the framework and the distribution of equivalent von Mises stress was investigated. Using the most critical scenario, the influence of the gradual failure of the cement layer, due to increasing load, on the bone -implant interface, were investigated., Results: The worst physiological loading condition was the one associated with a horizontal component (45°, 250 N). The 0°, 450 N load (relating to accidental or pathological condition) induced stress concentrations in the cortical bone comparable with those obtained for the tilted load, but with a greater extension to the cancellous bone. Y-TZP prosthetic elements determined minimum values of stress, due to vertical loads at the interface, while the microhybrid composite ones determined minimum stresses due to horizontal loads., Conclusion: Different material combinations for the abutment and the core influenced weakly the stress state at bone-implant interface, with a dependency closely related to the loading mode. The implant - prostheses system stress distribution depended on material choice. Furthermore progressive 45° loads with the gradual failure of the cement layer did not influence Von Mises stresses at bone-implant-interface.

INTRODUCTION.: The aim of this experimental study was to reduce the exothermic reaction during curing of the resins to cold. The significant exotherm generated by the reaction of polymerization of the resin curing involves many clinical complications including the high risk of necrosis against tooth. MATERIAL AND METHODS.: They were used four different types of self curing resins all based on methyl methacrylate, Jet Kit, Major Dentin, Dura Lay, Temporary Cold. The reaction of polymerization of the resins was done in Teflon pans and was monitored by a thermocouple which recorded the highest level reached by each temperature resin with and without additive. The polymerization reaction took place for each resin in the presence of an essential oil, the terpinolene, which acted as a "chain transfer" and different temperatures were recorded. RESULTS.: Resins Dura Lay and Jet kit showed a reduction of very high temperature in the presence of terpinolene, with a statistically significant difference compared to the same reaction without terpinolene Major resin dentin in the presence of the additive has reduced by 8.4°C peak temperature. Resin Temporary Cold has showed benefits with respect to peak temperature, but the reaction was much more 'consistent presence of the additive. DISCUSSION.: The system through which the chain transfer acts to lower the temperature of the reaction is that of chain transfer. Namely that interfere with the reaction of the polymer chains, by transferring these acrylic radicals are no longer active, ie, no longer able to bind to other monomer units, thus avoiding the excessive growth of macromolecules which are those that determine the temperature rise. This leads to the formation of more polymer chains with lower molecular weight.

STATEMENT OF PROBLEM.: The CAD-CAM technology has been developed to design and manufacture prosthetic structures with constant quality characteristics; in fact procedures are codified, manageable and repeatable. PURPOSE.: The purpose of this in vitro study is to evaluate the internal and marginal gap of zirconia casts made with a new CAD-CAM systematic that use Dental Wings laser scanner and Yenamak milling machine. MATERIAL AND METHODS.: 6 analogs of solid abutments of Straumann implants were used, fixed in plexiglass bases. The samples were scanned by Dental Wings laser; the file obtained by scanning of each probe was sent to the Yenamak D40 milling machine, then the casts were sintered in Protherm furnace. Then 6 samples were cemented with resin luting agent capsules (Relyx Unicem, 3M ESPE). The samples were incorporated in transparent epoxy resin. After resin hardening, the cylinders obtained were cut with a microtomes. These slices thus obtained were then polished with a Polisher sander with alumina dust decreasing grain. Each section was observed and photographed in reflected light with the aid of an optic microscope type, first at low magnification and then at higher magnification. RESULTS.: The overall average fitting of copings on the abutments was 32,87 μ. No differences were found in marginal fit on buccal and lingual sides, it was easily predictable because of the standard form of the used stumps. The recorded values for the marginal fit were lower than those of axial walls. The accuracy of adaptation was always achieved within the limits of clinical acceptability. CONCLUSIONS.: Within the limitations of this study, the system evaluated represents a valuable alternative to conventional prosthetic rehabilitation techniques.

Purpose: The aim of this study was to evaluate, by finite element analysis (FEA), the influence of finish line on stress distribution and resistance to the loads of a ZrO(2) crown and porcelain in implant-supported., Material and Methods: The object of this analysis consisted of a fxture, an abutment, a passing screw, a layer of cement, a framework crown, a feldspatic porcelain veneering. The abutment's marginal design was used in 3 different types of preparation: feather edge, slight chamfer and 50°, each of them was of 1 mm depth over the entire circumference. The ZrO(2)Y-TZP coping was 0.6 mm thick. Two material matching for the abutment and the framework was used for the simulations: ZrO(2) framework and ZrO(2) abutment, ZrO(2) framework and T abutment. A 600 N axial force distributed over the entire surface of the crown was applied. The numerical simulations with finite elements were used to verify the different distribution of equivalent von Mises stress for three different geometries of abutment and framework., Results: Slight chamfer on the matching ZrO(2) - ZrO(2) is the geometry with minimum equivalent stress of von Mises. Even for T abutment and ZrO(2) framework slight chamfer is the best configuration to minimize the localized stress. Geometry that has the highest average stress is one with abutment at 50°, we see a downward trend for all three configurations using only zirconium for both components., Conclusions: Finite element analysis. performed for the manifacturing of implant-supported crown, gives exact geometric guide lines about the choice of chamfer preparation, while the analysis of other marginal geometries suggests a possible improved behavior of the mating between ZrO(2) abutment and ZrO(2) coping. for three different geometries of the abutment and the coping.

We have examined the claims for advance maternity leave or prolonged benefits for breastfeeding addressed to Occupational Health Unity of Local Health Service 11 by women at harmful works in the period 2002-2005. The most frequent occupations were: shoemaker (29%), service company's employee (7%), tanners (7%), leather industry's employee (6%) and food industry's employee (6%). The most important risk factors were: bound postures, manual load handling, chemical hazards and biological agents. The numbers of claims increased during the period of interest. In the work place often risks for pregnancy and breastfeeding are not correctly assessed and women workers are not informed on their rights. The Occupational Health Unity of Local Health Service 11 tried to correct the lack of information for workers, employers, workers' representatives in health and safety and enterprise's occupational health physician.

We report the results obtained in 1992 concerning the determination of blood lead levels (PbB) in 1321 subjects of the general population living in ten villages/towns of the Florence district characterised by the presence of artistic ceramic factories. We reported also the PbB values found in 2330 adults, 280 children, 39 pregnant women and their correspondent umbilical cords, who were examined during the second biological monitoring campaign against the risk of lead intoxication according to the DPR 496/82. Median PbB values were 92.5 micrograms/l (range 15-520 micrograms/l) for males and 62.5 micrograms/l (range 11-343 micrograms/l) for females. The lower PbB median values were found in the district of Livorno (76.25 micrograms/l and 48.25 micrograms/l in males and females, respectively) and Arezzo (80.5 micrograms/l and 52 micrograms/l in males and females, respectively). In comparison with the results obtained for the general Italian population during the previous biological monitoring campaign carried out in 1985-86 we observed PbB median values about 40% lower for both males and females and PbB median values about 55% lower for children. A significant statistic correlation (r = 0.53) was found between PbB of pregnant women and their umbilical cords.

An evaluation was made of the degree of exposure to risk and the frequency of disorders attributable to biomechanical overload of the upper limb in workers employed on packaging in an ice cream factory. The risks were first evaluated against a checklist, then subsequently an assessment was made of the tasks found to feature the highest risks, using an ergonomic analysis method. The method identified several jobs, such as placing ice cream coupes and such like in boxes, as requiring a large number of actions per minute (> 30) and considerable muscular strength. The 59 female workers performing the packaging operations were given a risk-targeted physical examination. The clinical test detected an extremely high frequency of carpal tunnel syndrome, (7.1%) epicondylitis (5.2%) and scapulo-humeral periarthritis (3.5%) in the over 35 years age group, with respect to a control population not exposed to risk. The authors conclude that the repetitiveness of the actions, the use of gloves due to prolonged contact with frozen products and the effects of the low temperatures themselves, may have favoured the spread of the disorders that appeared in this population of workers. These findings must be further supported by more in-depth epidemiological studies.

The authors describe one case of perilunate dislocation. After reduction of the dislocation, there was a residual rotational subluxation of the scaphoid due to dorsal tearing of the scapho-triquetral and radio-scaphoid ligaments. The subluxation results in post-traumatic dorsal instability of the carpus. The authors report their clinical experience and conclude that clinical and radiographic diagnosis is not always easy and treatment, which is always surgical, must aim at joint stabilization and ligament reconstruction.