Torque changes of anchorage units in preadolescent patients treated with a digitally designed tooth-borne expander anchored to deciduous vs. permanent molars.

AIM: To compare the effects on permanent or deciduous anchorage dental units in patients treated with a digitally designed palatal expander. METHODS: Inclusion criteria were the following: presence of maxillary transverse deficiency, no previous orthodontic treatment, no extractions, absence of agenesis, congenital pathologies and cranio-maxillofacial malformations. Twenty patients (11 males, 9 females, 11 ± 1.8 years) received a digitally designed and metal printed palatal expander anchored on first permanent molars and 1 activation per day for 30 days (Group 1). Twenty-one patients (12 males, 9 females, 8.6 ± 1.4 years) received a digitally designed and metal printed palatal expander anchored on second deciduous molars and 2 activations per day for 14 days (Group 2). Digital intraoral scans were taken before expansion and after device removal, and torque and the palatal transverse diameter were digitally measured. The FDI notation was used to indicate each tooth CONCLUSION: Less dental torque augmentation was produced in Group 2. RESULTS: Significant intragroup differences over time were found in Group 1 considering the torque of teeth 1.6, 1.4, 1.3, 2.1, 2.4, 2.5, 2.6. Significant differences between groups were found regarding the longitudinal change in torque of teeth 1.5, 2.4 and 2.5. Significant intragroup differences over time were found in both groups considering all transverse diameter parameters. No significant differences were found between groups in the transverse diameter modifications over time. CONCLUSION: Less dental torque augmentation was produced in Group 2.

Perspectives in linear accelerator for FLASH VHEE: Study of a compact C-band system.

PURPOSE: In order to translate the FLASH effect in clinical use and to treat deep tumors, Very High Electron Energy irradiations could represent a valid technique. Here, we address the main issues in the design of a VHEE FLASH machine. We present preliminary results for a compact C-band system aiming to reach a high accelerating gradient and high current necessary to deliver a Ultra High Dose Rate with a beam pulse duration of 3µs. METHODS: The proposed system is composed by low energy high current injector linac followed by a high acceleration gradient structure able to reach 60-160 MeV energy range. To obtain the maximum energy, an energy pulse compressor options is considered. CST code was used to define the specifications RF parameters of the linac. To optimize the accelerated current and therefore the delivered dose, beam dynamics simulations was performed using TSTEP and ASTRA codes. RESULTS: The VHEE parameters Linac suitable to satisfy FLASH criteria were simulated. Preliminary results allow to obtain a maximum energy of 160 MeV, with a peak current of 200 mA, which corresponds to a charge of 600 nC. CONCLUSIONS: A promising preliminary design of VHEE linac for FLASH RT has been performed. Supplementary studies are on going to complete the characterization of the machine and to manufacture and test the RF prototypes.

Accurate spectra for high energy ions by advanced time-of-flight diamond-detector schemes in experiments with high energy and intensity lasers.

Time-Of-Flight (TOF) methods are very effective to detect particles accelerated in laser-plasma interactions, but they show significant limitations when used in experiments with high energy and intensity lasers, where both high-energy ions and remarkable levels of ElectroMagnetic Pulses (EMPs) in the radiofrequency-microwave range are generated. Here we describe a novel advanced diagnostic method for the characterization of protons accelerated by intense matter interactions with high-energy and high-intensity ultra-short laser pulses up to the femtosecond and even future attosecond range. The method employs a stacked diamond detector structure and the TOF technique, featuring high sensitivity, high resolution, high radiation hardness and high signal-to-noise ratio in environments heavily affected by remarkable EMP fields. A detailed study on the use, the optimization and the properties of a single module of the stack is here described for an experiment where a fast diamond detector is employed in an highly EMP-polluted environment. Accurate calibrated spectra of accelerated protons are presented from an experiment with the femtosecond Flame laser (beyond 100 TW power and ~ 1019 W/cm2 intensity) interacting with thin foil targets. The results can be readily applied to the case of complex stack configurations and to more general experimental conditions.

Maxillary "en masse" high-pull traction in Class II division 1 subjects: Which kind of skeletal outcomes does it produce?

AIM: The aim of the present prospective study was to evaluate if the treatment performed using high-pull traction on a Stephenson plate had real orthopaedic outcomes in subjects with severe Class II Division 1 malocclusion due to maxillary protrusion. MATERIALS AND METHODS: Twenty-three growing patients showing Class II Division 1 malocclusion (Stephenson plate group, SPG) were treated and compared with an untreated Class II control group (CG - 21 subjects selected from the database of Bolton-Brush Growth Study). Lateral cephalograms at T0 and T1 for both groups were analysed using cephalometric tracing by Jarabak, Pancherz and Ghosh-Nanda. RESULTS: Orthopaedic forces were applied in SPG. SPG group showed significantly greater decrease than CG group of SNA° (-1.4° vs +0.7°), ANB° (-1.3° vs +0°), WITS (-1° vs 0.6°), overjet (-4.1 mm vs +0.3 mm), molar relationships (-6.1° mm vs -0.1 mm) and upper incisors proclination (1/SpP, -10.3° vs -1°). The maxilla substantially maintained its position (A/OLp +0.3 mm, SNA° -1.4°) while the mandible slightly grew (Pg/OLp +1.7 mm; SNB° + 0.7°). Facial pattern and AFA/AFP ratio did not change. CONCLUSION: The high-pull traction on the Stephenson plate produced more dental than skeletal outcomes in growing subjects, despite of the application of orthopaedic forces.

Design and optimization of a compact laser-driven proton beamline.

Laser-accelerated protons, generated by irradiating a solid target with a short, energetic laser pulse at high intensity (I > 1018 W·cm-2), represent a complementary if not outperforming source compared to conventional accelerators, due  to their intrinsic features, such as high beam charge and short bunch duration. However, the broadband energy spectrum of these proton sources is a bottleneck that precludes their use in applications requiring a more reduced energy spread. Consequently, in recent times strong effort has been put to overcome these limits and to develop laser-driven proton beamlines with low energy spread. In this paper, we report on beam dynamics simulations aiming at optimizing a laser-driven beamline - i.e. a laser-based proton source coupled to conventional magnetic beam manipulation devices - producing protons with a reduced energy spread, usable for applications. The energy range of investigation goes from 2 to 20 MeV, i.e. the typical proton energies that can be routinely obtained using commercial TW-power class laser systems. Our beamline design is capable of reducing the energy spread below 20%, still keeping the overall transmission efficiency around 1% and producing a proton spot-size in the range of 10 mm2. We briefly discuss the results in the context of applications in the domain of Cultural Heritage.

The efficacy of Italian guidelines in promoting oral health in children and adolescents.

AIM: The purpose of the study was to evaluate the efficacy of the guidelines on oral health published by the Italian Health Ministry. STUDY DESIGN: 1239 patients (582 girls and 657 boys) with a mean age of 4.46 (SD 2.81) years were evaluated before application of the guidelines by paediatricians (T0) for the presence of caries, gingivitis, diseases of the oral mucosa, and malocclusion. Only patients aged 6 months, 3 years, 6 years, and 9 years at T0 were taken into consideration. All patients were reevaluated after application of the ministerial guidelines (T1). METHODS: the study took place over a 3-year period. Enrolled patients referred to the outpatient clinics of three paediatricians of the Province of Genoa who strictly applied the ministerial guidelines. STATISTICS: Chi square test analysis was performed to evaluate a statistically significant decrease in the incidence of caries, gingivitis and diseases of the oral mucosa. RESULTS: After a 3-year follow-up collected data underlined a statistically significant decrease in the incidence of dental caries, gingivitis and oral mucosal diseases after implementation of the recommended ministerial guidelines. A statistically significant decrease of malocclusions was also evident in the elder patients (12 years old at T1). CONCLUSION: The accurate implementation of the Guidelines is supported. Only collaboration and increased synergy between paedodontists and paediatricians can fulfill the objectives which were the reason for publishing the "National guidelines for the promotion of oral health and the prevention of oral diseases in developmental age".

Denture-frame modifications in class III patients treated with rapid palatal expansion and facemask: a prospective controlled study.

AIM: The aim of this prospective controlled investigation was to analyze the short-term cephalometric treatment outcomes, according to the denture frame analysis proposed by Sato, of rapid palatal expansion (RPE) and facial mask (FM) therapy. METHODS: A group of 21 patients with Class III malocclusion treated with the RPE and FM (TG) was compared with untreated Class III controls (CG). The mean age of treatment group was 8.8 years; treatment consisted of 4 weeks of RPE activation (0.20 mm/die) followed by 14 hours wear of the FM for a mean of 333.1 days. As CG were used the data published by Tanaka and Sato. Pre- and post-treatment cephalometric values were compared and statistical analyzed with one-sample t-test. A P-value <0.05 was considered statistically significant. RESULTS: For almost all parameters the differences pre and post treatment values resulted significantly different compared to those observed in CG. Regarding conventional occlusal plane (POC) values some differences compared to control group were found but they were not statistically significant (P=0.067) while for aterior occlusal plane (POA) no differences where noticed. CONCLUSION: This study revealed an increase in inter-jaw angle during treatment with FM and RPE, an increase in the inclination of the posterior occlusal plane with respect to the Frankfurt plane and a posterior and lower adaptation of the mandible.

Evaluation of the cephalometrics modification of growing Class II Division I patients after treatment with the PUL appliance: a pilot study.

AIM: The aim of this preliminary study was to evaluate short-term dentoskeletal changes obtained with a functional appliance for Class II Division I malocclusions called propulsor universal light (PUL). METHODS: Fifteen Class II Division 1 patients (10.6±1.2 years) were consecutively treated by one expert operator with PUL appliance and they were compared with a longitudinal group of Class II Division I untreated patients (9.9±1.9 years) matched for pubertal growth spurt stage and sex. Lateral cephalograms were taken before PUL therapy and at the end of treatment. The mean duration of treatment was 11.2±0.3 months; t-test or Mann-Whitney U-test was used (P <0.05). RESULTS: Statistically significant reduction of the overjet, WITS and ANB was noticed in treated group as well as a significant improvement of CoGo and Ramus. CONCLUSION: Class II Division I malocclusion in the short term was efficiently treated by PUL appliance with both skeletal and dentoalveolar changes.

Dorsolateral striatum and dorsal hippocampus: a serial contribution to acquisition of cue-reward associations in rats.

In laboratory rodents, procedural and declarative-like memory processes are often considered operating in dual, sometimes even competing with each other. There is evidence that the initial approach of a repetitive task first engages a hippocampus-dependent declarative-like memory system acquiring knowledge. Over repetition, there is a gradual shift towards a striatum-dependent response memory system. In the current experiment, Long-Evans male rats with bilateral, fiber-sparing ibotenic acid-induced lesions of the dorsolateral striatum or the dorsal hippocampus were trained in an olfactory associative task requiring the acquisition of both a procedural and a declarative-like memory. Rats with dorsolateral striatum lesions, and thus an intact hippocampus, were impaired on both sub-categories of memory performance. Rats with dorsal hippocampal lesions exhibited a substantial deficit in learning the declarative-like cue-reward associations, while the acquisition of the procedural memory component of the task was not affected. These data suggest that the dorsolateral striatum is required to acquire the task rule while the dorsal hippocampus is required to acquire the association between a given stimulus and its associated outcome. The finding is that the dorsolateral striatum and the dorsal hippocampus most probably contribute to successful learning of cue-reward associations in a sequential (from procedural to declarative-like memory) order using this olfactory associative learning task.

Early functional treatment in Class II division 1 subjects with mandibular retrognathia using Fränkel II appliance. A prospective controlled study.

AIM: This was to clarify dentoalveolar, skeletal and facial profile modifications induced by Fränkel II functional treatment in Class II division 1 subjects in prepubertal stages CS1-2. MATERIALS AND METHODS: Evaluation of 25 caucasian subjects (15 males, 10 females), mean age 8y 11m, in vertebral stages CS1-2. The mean duration of functional treatment was 1y 11m. STUDY DESIGN: Prospective controlled study. The sample was evaluated at T0, start of treatment, and T1, end of Fränkel II therapy. Untreated subjects in Class II division 1 were the control group. STATISTICS: T-test for paired data was calculated before and after treatment (P< 0.05). RESULTS: A statistically significant increase between T0 and T1 was obtained for SNB (p = 0.022), ANB (p <0.001), Mx/Mn differential (p = 0.001), Co-Go-Me (p = 0.014), OJ (p < 0.001), OB (p = 0.042), IMPA (p = 0.021) . OJ (p < 0.001) and OB (p = 0.003) showed a higher significant change in the Fränkel group compared to control group. CONCLUSION: The Fränkel II appliance produced, in CS1-2 subiects, significant effects in teeth position, skeletal modifications and soft tissue changes, although the pubertal growth spurt would occur at least two years later.

Temporary anchorage device stability: an evaluation of thread shape factor.

The resistance to extraction of temporary anchorage devices (TADs) depends on various factors, including miniscrew design, shear strength, and bone density. This research introduces the thread shape factor (TSF) as a new factor for the evaluation of TAD mechanical properties. The authors evaluated three TADs for a total of 27 tests: Mini-impianto autoforante (Leone, 1.75 mm diameter and 8 mm length), Orthoscrew (Leader Ortodonzia, 1.65 mm diameter and 9 mm length), and MAS (Miniscrew Anchorage System, 1.3 mm diameter and 11 mm length). For each TAD, the images were acquired via a 20.00 kV scanning electron microscopy to measure their respective mean depth of thread (D), pitch (P), and the relationship between the two (TSF). Subsequently, pullout tests on organic bone analogue were carried out using a testing machine; a crosshead speed of 2 mm/minutes was applied. A two-way analysis of variance was performed to evaluate the interaction between the type of miniscrew and the cortical thickness. A post hoc analysis for single comparisons was subsequently employed. In addition, if homogeneity of variances was not rejected, Scheffè's test was performed, while Tamhane's test was carried out if the homogeneity of variance assumption was not met. Univariate linear regression models were fitted to evaluate the relationship between the outcomes and TSF, D, and P separately. A P value of 0.05 was considered statistically significant. From univariate linear regression, TSF, D, and P were statistically significant predictors of 'peak load'. The tests showed that TSF has a statistical significance for describing the mechanical competency of TADs.

Signal transduction on enzymes: the effect of electromagnetic field stimuli on superoxide dismutase (SOD).

Protein functions and characteristics can highly differ from physiological conditions in presence of chemical, mechanical or electromagnetic stimuli. In this work we provide a rigorous picture of electric field effects on proteins behavior investigating, at atomistic details, the possible ways in which an external signal can be transduced into biochemical effects. Results from molecular dynamics (MD) simulations of a single superoxidismutase (SOD) enzyme in presence of high exogenous alternate electric fields will be discussed.

Incidence and distribution of deciduous molar ankylosis, a longitudinal study.

AIM: To study incidence and distribution of deciduous molar ankylosis. MATERIALS AND METHODS: study design: longitudinal retrospective study. A total of 512 consecutive subjects (aged 5 to 15 years) were examined at the Orthodontics and Paediatric Dentistry Department of the Genoa University School of Dentistry; for each subject an ortopantomography x-ray was taken. RESULTS: Thirty-four children were affected by deciduous molars ankylosis (6.6%). A statistically significant difference was revealed between the distributions: the lower deciduous molars were ankylosed more frequently than the upper ones (P < 0.001); the second deciduous molars were ankylosed more frequently than the first molars (P < 0.001). No statistical significance was found between sex and number of infraoccluded teeth (P = 0.74). CONCLUSION: This study found an incidence of deciduous molar ankylosis of about 6.6%; the lower deciduous molars and second deciduous molars were ankylosed more frequently (P < 0.001).

Three-dimensional tomographic mapping related to primary stability and structural miniscrew characteristics.

OBJECTIVES: To evaluate the maxilla, mandible, and cortical plates on computerized tomographic (CT) scans to achieve accurate three-dimensional bone thickness measurements. SETTING AND SAMPLE POPULATION: We selected the CT scans of 25 subjects (among 102), aged 18-58 years (10 men, 15 women), with nearly complete dentition. MATERIAL AND METHODS: We performed interradicular and bucco-lingual (including cortical plate thickness) measurements in dental areas distal to the canines in both alveolar arches, at three levels (5, 8, and 11 mm) from the alveolar ridge. RESULTS: The mean thicknesses of the cortical plates in the maxilla were 1.10 mm buccally and 1.27 mm on the palatal side (p < 0.05). In the mandible, cortical plates were 2.23 mm buccally and 2.02 mm lingually. Mandibular buccal and lingual cortical plates became thicker distally in the second and third molar areas. There was considerable variation in cortical thickness (from 0.25 to 5.50 mm). Based on interradicular distances, only 13% of measured sites in the maxilla were suitable for miniscrew insertion (≥3.3 mm), but 63% of sites were suitable in the mandible. CONCLUSION: This study showed considerable individual variation in bone thickness. Our data suggested that the palatal/lingual side may provide greater primary stability for miniscrews. The palatal area, between the second upper bicuspid and the first molar, appeared to be the most suitable area for tapered 7- to 9-mm miniscrews, starting at 1.5-2 mm from the alveolar crest.

Experimental demonstration of emittance compensation with velocity bunching.

In this Letter we report the first experiments aimed at the simultaneous demonstration of the emittance compensation process and velocity bunching in a high brightness electron source, the SPARC photoinjector in INFN-LNF. While a maximum compression ratio up to a factor 14 has been observed, in a particular case of interest a compression factor of 3, yielding a slice current of 120 A with less than 2 microm slice emittance, has been measured. This technique may be crucial in achieving high brightness beams in photoinjectors aiming at optimized performance of short wavelength single-pass free electron lasers or other advanced applications in laser-plasma accelerators.

Manual orthodontic vs. oscillating-rotating electric toothbrush in orthodontic patients: a randomised clinical trial.

AIM: To compare the efficacy of manual and oscillating-rotating electric toothbrushes in removing plaque and reducing gingivitis in patients with fixed orthodontic appliances. STUDY DESIGN: Randomised clinical trial. MATERIALS AND METHODS: 20 subjects aged 10 to 14 years (8 males; 12 females) scheduled for fixed orthodontic treatment were enrolled, randomly divided into two groups, A and B, and later assigned electric or manual toothbrushes, respectively. Three months after orthodontic appliance bonding (T1), and again after a further 4 (T2) and 8 (T3) weeks, plaque levels (PI), gingival bleeding (GBI) and hypertrophy were assessed. RESULTS: Between the two toothbrush types, statistically significant differences in PI were detected from T2 to T3 (P value 0.010), but not from T1 to T2. In contrast, the GBI was significantly different from T1 to T2 (P value 0.025), but not from T2 to T3. CONCLUSION: With respect to the manual orthodontic toothbrush, the electric oscillating-rotating toothbrush was found to better improve both PI and GBI.

Complete recovery of olfactory associative learning by activation of 5-HT4 receptors after dentate granule cell damage in rats.

Bilateral intradentate injections of 3.0microg of colchicine induced a substantial loss of granule cells and damage to the overlying pyramidal cell layer in region CA1 in adult male Long-Evans rats. All rats with such lesions showed a significant associative learning deficit in an olfactory discrimination task, while being unimpaired in the procedural component of this task. Injection of a partial selective 5-HT(4) agonist (SL65.0155; 0.01mg/kg, i.p., vs. saline) before the third of six training sessions enabled complete recovery of associative learning performance in the lesioned rats. Activation of 5-HT(4) receptors by a selective agonist such as SL65.0155 might therefore provide an opportunity to reduce learning and memory deficits associated with temporal lobe damage, and could be useful for the symptomatic treatment of memory dysfunctions related to pathological aging such as Alzheimer's disease.

Analysis methodology of movable emittance-meter measurements for low energy electron beams.

The design of photoinjectors for modern free electron laser linac relies heavily on particular beam behavior in the few meters after the gun. To experimentally characterize it a movable emittance meter was proposed and built [L. Catani et al., Rev. Sci. Instrum. 77, 093301 (2006)] based on the beam slicing technique. This paper addresses all the aspects of analysis of the data acquired with the emittance meter and common to any slit based emittance measurement for low energy beams.

Direct measurement of the double emittance minimum in the beam dynamics of the sparc high-brightness photoinjector.

In this Letter we report the first experimental observation of the double emittance minimum effect in the beam dynamics of high-brightness electron beam generation by photoinjectors; this effect, as predicted by the theory, is crucial in achieving minimum emittance in photoinjectors aiming at producing electron beams for short wavelength single-pass free electron lasers. The experiment described in this Letter was performed at the SPARC photoinjector site, during the first stage of commissioning of the SPARC project. The experiment was made possible by a newly conceived device, called an emittance meter, which allows a detailed and unprecedented study of the emittance compensation process as the beam propagates along the beam pipe.

Saturation and electron-beam lifetime in a storage ring free-electron laser.

We present a phenomenological treatment of free-electron laser storage ring saturation dynamics. The model includes longitudinal instabilities, Touschek intrabeam scattering, and nonzero off-energy-function contributions. The model predictions are compared with Super ACO experimental results and the agreement is shown to be satisfactory.