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Objective:

The aim of this study was to evaluate the biomechanical preparation of flattened root canals using the following systems: Endo-Eze AET stainless steel oscillatory instruments (Ultradent) and RaCe rotary NiTi instruments (FKG Dentaire).

Materials and Methods:

Twenty extracted human mandibular incisors were randomly assigned to two groups: Group 1 - Instrumentation with oscillatory Endo-Eze AET files (oscillatory technique); Group 2 - Instrumentation with rotary NiTi RaCe files (rotary technique). The teeth were decoronated, had their apices and coronal openingssealed with sticky wax and were embedded in crystal-clear orthophtalic polyester resin. The roots were sectioned transversally with diamond discs at 10 mm (middle third) and 5 mm (apical third) from the apex and the segments were reassembled for instrumentation. The sections were photographed before and after root canal instrumentation and evaluated with respect to whether the original root canal shape was modified by instrumentation. To evaluate the differences in the root canal shape before and after biomechanical preparation, scores were given regarding the instruments touch on the intracanal walls.

Results:

In middle third of the root canals instrumented with the rotary system, there was a change in the original canal anatomy (p<0.05), with formation of a protuberance in the mesiodistal direction. This protuberance did not occur when the oscillatory instrumentation was used. The oscillatory system had better results in the middle and apical thirds as evaluated by Dunn’s multiple-comparison test (p>0.05).

Conclusion:

Under the tested conditions, Endo-Eze oscillatory system yielded the instrumentation of all flattened root canal walls, maintaining the canal original shape throughout the biomechanical preparation, and was more effective than RaCe rotary system.  相似文献   
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Lasers in Medical Science - Chagas disease is endemic in Latin America and increasingly found in non-endemic countries. Its treatment is limited due to the variable efficacy and several side...  相似文献   
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BackgroundPleckstrin homology domain family A (PHLDA) genes play important roles in cancer cellular processes, including inhibiting Akt activation, repressing growth factor signaling, inhibiting the negative feedback of EGFR/ErbB2 signaling cells, and inducing apoptosis. However, the prognostic significance of PHLDA in non-small cell lung cancer (NSCLC) and malignant pleural mesothelioma (MM) remains unclear. The present study investigates the associations between PHLDA expression patterns and their prognostic value in lung adenocarcinoma (LUAD) and MM.MethodsWe analyzed PHLDA family members at the genomic level in silico to explore their mRNA expression pattern and predictive significance in LUAD and MM. We then created a PHLDA–drug interaction network and a protein-protein interaction (PPI) network using different databases. Finally, we immunohistochemically assessed the protein expression of each PHLDA family member on tissue microarrays (TMAs) in both LUAD and MM cohorts with long-term follow-up.ResultsWhile PHLDA1 mRNA expression in both LUAD and MM was lower than that of normal tissue, PHLDA2 mRNA was significantly overexpressed in LUAD, and PHLDA3 mRNA was overexpressed in MM. In NSCLC, both low PHLDA1 mRNA expression and high PHLDA3 mRNA expression correlated with worse overall survival (OS) (P<0.01), whereas high PHLDA2 mRNA expression was associated with better OS (P<0.01). In MM, patients presenting high PHLDA1 and PHLDA2 mRNA expression had poor OS (P=0.01 and P<0.01, respectively). In addition, the PHLDA-drug interaction network indicated that several common drugs could potentially modulate PHLDA expression, and the PPI network suggested that PHLDA1 interacts with Notch family members, whereas PHLDA3 interacts with TP53. Our results also showed that the expression of PHLDA2 and PHLDA3 was significantly higher in LUAD and MM than that of PHLDA1 (P<0.05) and was associated with the risk of death. While patients with PHLDA2 >85.09 cells/mm2 had a low risk of death (P=0.01) and a median survival time of 48 months, those with PHLDA3 <70.38 cells/mm2 had a high risk of death (P=0.03) and a median survival time of 34 months.ConclusionsWe shed light on the role of the PHLDA family as promising predictive biomarkers and potential therapeutic targets in LUAD and MM.  相似文献   
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Clinical Oral Investigations - This study evaluated the effectiveness of class II restorations, in permanent teeth, through the ART technique in comparison to composite resin. Participants (154),...  相似文献   
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There is an urgent need for interventions that improve healing time, prevent amputations and recurrent ulceration in patients with diabetes‐related foot wounds. In this randomised, open‐label trial, participants were randomised to receive an application of non‐cultured autologous skin cells (“spray‐on” skin; ReCell) or standard care interventions for large (>6 cm2), adequately vascularised wounds. The primary outcome was complete healing at 6 months, determined by assessors blinded to the intervention. Forty‐nine eligible foot wounds in 45 participants were randomised. An evaluable primary outcome was available for all wounds. The median (interquartile range) wound area at baseline was 11.4 (8.8‐17.6) cm2. A total of 32 (65.3%) index wounds were completely healed at 6 months, including 16 of 24 (66.7%) in the spray‐on skin group and 16 of 25 (64.0%) in the standard care group (unadjusted OR [95% CI]: 1.13 (0.35‐3.65), P = .845). Lower body mass index (P = .002) and non‐plantar wounds (P = .009) were the only patient‐ or wound‐related factors associated with complete healing at 6 months. Spray‐on skin resulted in high rates of complete healing at 6 months in patients with large diabetes‐related foot wounds, but was not significantly better than standard care (Australian New Zealand Clinical Trials Registry: ACTRN12618000511235).  相似文献   
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