Search

This study aims to estimate the microbial presence on the surface of different brand new NiTi endodontic instruments for clinical use.Eleven different types of NiTi rotary endodontic instruments, obtained from their fresh opened original packages, were assigned to three different groups, according to packaging type and sterilization and tested for bacterial contamination. Isolated bacteria were identified by using standard microbiological methods and then counted. Differences observed in groups were analyzed statistically by using the one-way analysis of variance (ANOVA) for dependent samples and the Tukey HSD post hoc test.Statistical differences were found between instruments delivered in plastic boxes which bacterial count resulted higher than those obtained from instruments delivered in blisters (p0.01).Some brand new endodontic instruments showed degrees of bacterial contamination that both quantitatively and qualitatively deserve to be considered in clinical procedures.

OBJECTIVE: Aim of the present study was to evaluate the cytotoxicity of Real Seal 1 compared to other commercially available endodontic filling materials: Real Seal (SybronEndo, Orange, CA, USA) and Thermafil (Tulsa Dental, Tulsa, OK, USA).,MATERIAL AND METHODS: Periodontal ligament cells from healthy patients were cultured. The eluate of Real Seal 1(TM) (RS1), Real Seal (RS) and Thermafil (TF) samples was used for the cells viability tests, both diluted (50%) or undiluted (100%). Incubation of the specimens was performed in culture medium for 24 h, 48 h and 72 h at 37 °C under sterile conditions. The cellular mortality was evaluated by MTT test. Results were statistically analysed and the statistical significance was set at p< 0.05.,RESULTS: None of the studied materials showed toxic effects during the period of observation (0 -72 h) when compared to the control group. Only RS induced a very modest increase in cell mortality (about 3% at both concentrations used, during the first 24 hours), when increasing the incubation time, however, only the lower concentration continued to show modest toxicity.,CONCLUSIONS: Results of the present study showed that all tested materials did not exhibit cytotoxic effects when compared to the control group.

To evaluate the efficacy and safety of a new 5.9% hydrogen peroxide liquid, invisible gel, (Colgate Simply-White Whitening Gel).A total of 30 subjects were enrolled into the study and divided into two treatment groups (Colgate vs. placebo gel). Efficacy was assessed using VITA shade scores and safety evaluations were performed including the examination of plaque index (PI), bleeding index (BOP), gingival recession and dentin hypersensitivity. Statistical analysis was performed to determine the mean change from baseline.The new whitening gel containing 5.9% hydrogen peroxide was significantly effective in lightening tooth shade. After only 2 weeks, patients enrolled in the study exhibited an overall mean 4.48-shade improvement from baseline, which was significantly greater than placebo group and far exceeded the ADA minimum requirements to claim "clinical efficacy". In the new Colgate Simply White Clear Whitening Gel group, periodontal health (PI and BOP) improved with time overall. Moreover, dentin hypersensitivity did not significantly increase, and all treatments were generally well tolerated.The new Colgate Simply White whitening gel containing 5.9% hydrogen peroxide allowed consistent bleaching using minimal contact time, without adversely impacting overall tolerability.

The aim of the present study was to establish the prevalence and the type of psychiatric disturbances in a group of 42 obese children (18 boys aged from 6.8 to 13.8 years and 24 girls aged from 2.8 to 15.4 years; weight excess mean +/- 1SD 146.7 +/- 17.4%) and to evaluate the efficacy of a psychological approach of obesity in childhood. The children were in a normal caloric diet and they were encouraged to reach a "target weight" in a given period of time. 22 children were randomly assigned the "analyzed" group (auxological, alimentary and psychological evaluation) and 20 to the "control" group (auxological and alimentary assessment). The psychological evaluation was performed in 20 children (the parents of two children refused to give their consent) by the following tests: creative drawing test; draw a man test (Machover); draw a tree test (Koch); draw a family test (Co-man); Rorschach's test; TAT (Thematic Apperception Test) or, in the younger, the Düss's tales. The results of these psychological tests have been communicated to the patients and or parents. The children were followed for a period of 7 months. We found in 8 children (40%) personality disturbances (which were severe in two cases) and a psychological support was started. The observed main types of disturbances were depression and anxiety. Both were due to a missing harmony between their parents, to a difficult relationship either with their mother or with other children, and to the bad child's opinion of himself. In 4 subjects a psychological support associated with diet promoted a slow, progressive and continuous weight loss.(ABSTRACT TRUNCATED AT 250 WORDS)

The aim of the present study was to investigate the in vitro sealing ability of a new obturating material (Real Seal 1, SybronEndo, Orange, CA, USA) and compare it with the Thermafil (Dentsply Maillefer, Baillargues, Switzerland) and One-Step systems (CMS Dental, Copenhagen, Denmark).Forty-four freshly extracted lower premolars teeth were selected and a root canal treatment was performed using a crown-down Nickel-Titanium rotary preparation technique. Teeth were randomized into three groups (N.=14): 1) Thermafil group; 2) One/step group; 3) Real Seal 1 (RS1) group. The remaining two teeth served as controls. A fluid filtration system device was utilized to assess quantitatively the microleakage. Statistical analyses were performed by ANOVA and significance was set at 95%.Data clearly showed that the RS1 provided the best results, showing a minimal leakage after 24 hours. Statystical analysis showed a significant difference about the RS1 group, the Thermafil and One/Step group, while no significant differences were noted between these last two groups. Results show that the number of teeth that had no (=0) leakage was higher in the RS1 group (8 specimens) than in the remaining ones (1 and 1 specimen, respectively).Under the conditions of the present experimental test, the new RS1 material (carrier-based Resilon) provided excellent preliminary results showing sealing ability at 24 hours significantly better that traditional carrier-based gutta-percha systems.

Background: The Epiphany endodontic obturation system, which was developed for use with all current root canal-filling techniques by substituting for gutta-percha and sealer, has been recently modified by eliminating the priming step and introducing a new self-etch, dual-cure, resin-based sealer; Epiphany SE. As with all new endodontic compounds, this novel materials should undergo preliminary testing for biocompatibility. The aim of the present study was to investigate the in vitro cytotoxicity of Epiphany SE and to compare it with the original Epiphany scaler and with a commonly used endontic scaler (Pulp Canal Sealer). Material/Methods: Mouse 3T3 fibroblasts were seeded and cultured, and extracts of each of the cemented scalers were added. After a 24-hour incubation, cell viability was evaluated by neutral red uptake assay, which is an indicator of membrane permeability. The greater the cell mortality (measured as a percent-age), the greater the toxicity of the scaler. Results: Results showed that all 3 of the tested sealers exhibited cytotoxic effects compared to the control group (P0.05) were noted among the scalers. Conclusions: Our results showed satisfactory biocompatibility of the new Epiphany SE sealer, which showed similar biocompatibility to the original Epiphamy sealer and to the traditional zinc oxide eugenol-based scaler.

The aim of the present study was to evaluate the bending properties of twisted file instruments, and compare them with other commercially available nickel-titanium (NiTi) instruments (Mtwo and Hero) manufactured with traditional methods.Despite NiTi superelastic properties, flexibility of NiTi instruments is limited by size and taper. A new manufacturing process involving twisting of a ground blank combined with heat treatment has been developed by SybronEndo, aiming to produce a NiTI rotary file with superior flexibility: the Twisted File (TF). Experimental procedures strictly followed the testing methodology described in ISO 3630-1. Bending moment was measured when the instrument attained a 45 degrees bend. Data were collected and statistically analyzed.Results showed that TF were the most flexible instruments, with a significant improvement in flexibility (P0.05). ranging from 100% to 250% over the other tested instruments. Even if flexibility is also influenced by instruments design, such a great improvement is mainly related to the new TF manufacturing process.The flexibility is influenced by instruments design, such a great improvement is mainly related to the new manufacturing process developed by SybronEndo, which seems to play a major role in increasing the flexibility of TF instruments.

Ameloblastic fibroma (AF) is defined in WHO classification as a ''neoplasm composed of proliferating odontogenic epithelium embedded in a cellular ectomesenchymal tissue that resembles dental papilla, and with varying degrees of inductive change and dental hard tissue formation''. AF is a rather uncommon tumor, accounting for only 2.5% of all odontogenic tumors. AF is a true mixed tumor, in which the epithelial and ectomesenchymal elements are neoplastic. AF raises at any age, ranging from 6 months to 42 years (mean 14.6 to 15.5 years); it does not show sex predilection. The lesion occurs in nearly 70% of cases in posterior areas of the mandible. Patients exhibit swelling of the jaw; pain is not usually described. Authors present a clinical and surgical management of an early onset of a large mandibular ameloblastic fibroma in a 6-year-old girsl.

To clinically evaluate a new system for at-home tooth whitening (Colgate Simply-White Whitening Gel), by comparing tooth color improvement and adverse event incidence after 14-days treatment.22 subjects (aged 21-46 years) were enrolled into the study. Tooth color and safety assessments were conducted at baseline and following a 2-week at-home treatment. Efficacy was assessed using VITA shade scores. Safety evaluations were performed including the examination of plaque index (PI), bleeding index (BOP), gingival recession and dentin hypersensitivity. Statistical analysis was performed to determine the mean change from baseline.The new whitening gel releasing 5.9% hydrogen peroxide was significantly effective in lightening tooth shade. After only 2 weeks, patients enrolled in the study exhibited an overall mean 3.56-shade improvement from baseline, far superior than minimum values established in ADA Guidelines for the acceptance of peroxide-containing oral hygiene products. Periodontal health (PI and BOP) improved with time overall. Dentin hypersensitivity slightly increased, but it was very well tolerated. No patient discontinued study participation due to such an adverse event. Therefore, it was concluded that the new Colgate Simply White Clear Whitening Gel provided clinically proven, safe and effective at-home tooth whitening.

Studies on the optical absorbance spectra of Fricke xylenol orange gel dosimeters were performed, in the wavelength range from 300 nm to 800 nm, in order to highlight some particular characteristics that can affect the achievable precision. The spectra are different mainly due to the different types of xylenol orange that was used and to a lower extent due to the different gelling agents (agarose or gelatine). The characteristic of variation of absorbance spectra versus dose, however, are similar in the various cases and can explain some peculiarities, as apparent effects of dose threshold. Changes of spectral shapes appear over the time after irradiation. Magnetic resonance measurements performed at various times after irradiation only reveal the slow changes due to the auto-oxidation effect, proving therefore that the modality of chelation of ferric ions by xylenol orange can affect the observed changes in the optical absorbance spectra.

Fiber-optic-coupled scintillation dosimeters are characterized by their small active volume if compared to other existing systems, and are therefore particularly suited for internal in vivo dosimetry. Due to possible differences between calibration conditions (i.e., room temperature) and conditions of clinical application (i.e., body temperature), their temperature dependence should be accurately studied. In this work, the temperature dependence of a Ce3+ doped SiO2 scintillation detector coupled to a SiO2 optical fibre was investigated for high dose rate brachytherapy applications. To this aim, two sets of irradiations with two different Ir-192 sources were performed in a water bath phantom at water temperatures ranging between 17°C and 40.4°C (Experiment 1). The relative response of the dosimeter was collected and analyzed. The same experiment was repeated with a second optical fibre which was designed without the active Ce3+ doped part at its end (Experiment 2) as well as by changing the length of the passive fibre inserted in water (Experiment 3). The two sets of measurements of experiment 1 were in accordance, indicating a linear increase with temperature of the scintillator sensitivity, with an average increase of 0.27 ± 0.2%/°C. In experiment 2, a 0.5%/°C increase of the collected signal resulted for the passive fibre. No significant difference of the temperature coefficient was found by changing the length of the fibre inserted in water (experiment 3). The obtained results show that a temperature-specific correction factor should be adopted at temperatures different than room temperature (e.g. for in vivo internal dosimetry). Further studies are required to understand the observations. © 2014 Elsevier Ltd. All rights reserved.

Fiber-optic-coupled scintillation dosimeters are characterized by their small active volume if compared to other existing systems. However, they potentially show a greater stem effect, especially in external beam radiotherapy where the Cerenkov effect is not negligible. In brachytherapy, due to the lower energies and the shorter high dose range of the employed sources, the impact of the stem effect to the detector accuracy might be low. In this work, the stem effect of a Ce3+ doped SiO2 scintillation detector coupled to a SiO2 optical fiber was studied for high dose rate brachytherapy applications. Measurements were performed in a water phantom at changing source-detector mutual positions. The same irradiations were performed with a passive optical fiber, which doesn't have the dosimeter at its end. The relative contribution of the passive fiber with respect to the uncorrected readings of the detector in each one of the investigated source dwell positions was evaluated. Furthermore, the dosimeter was calibrated both neglecting and correcting its response for the passive fiber readings. The obtained absolute dose measurements were then compared to the dose calculations resulting from the treatment planning system. Dosimeter uncertainties with and without taking into account the passive fiber readings were generally below 2.8% and 4.3%, respectively. However, a particular exception results when the source is positioned near to the optical fiber, where the detector underestimates the dose (-8%) or at source-detector longitudinal distances higher than 3cm. The obtained results show that the proposed dosimeter might be adopted in high dose rate prostate brachytherapy with satisfactory accuracy, without the need for any stem effect correction. However, accuracy further improves by subtraction of the noise signal produced by the passive optical fiber. © 2013 Elsevier Ltd.