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To examine the effect of molding angle on the trueness and defects associated with removable partial denture (RPD) frameworks fabricated by selective laser melting (SLM).A plaster model of a partially edentulous mandibular arch classified as Kennedy class II modification 1 was used. After obtaining the 3D data of the model (design data), a framework was designed using CAD software. Based on the design data, three different molding angle conditions (0°, 45°, and -45°) were set in the CAM software. The frameworks were fabricated by SLM under each condition, and 3D data were captured (fabrication data). The design and fabrication data were superimposed using 3D inspection software to verify the shape errors. The number of support structures was then measured. To examine the internal defects, micro-computed tomography (µCT) was performed for void analysis. Surface roughness was measured using a laser microscope.The overall shape errors of the RPD framework were smaller under the 0° condition compared with the others, and the largest number of support structures was observed at 0°. Many internal defects were observed in the large components of the framework at 45° and -45°. The surface roughness was the smallest at -45°.The trueness and defects associated with the RPD frameworks were affected by the difference in the SLM molding angle.

Introduction: Direct pulp capping (DPC) procedures require the placement of a bioactive material over an exposure site without selective pulp tissue removal. This web-based multicentered survey had 3 purposes: (1) to investigate the factors that affect clinicians’ decisions in DPC cases, (2) to determine which method of caries removal is preferred, and (3) to evaluate the preferred capping material for DPC. Methods: The questionnaire comprised 3 sections. The first part comprised questions regarding demographic features. The second part comprised questions on how treatment plans change according to factors such as nature, location, number and size of the pulp exposure, and patients’ age. The third part composed of questions on the common materials and techniques used in DPC. To estimate the effect size, the risk ratio (RR) and 95% confidence interval (CI) were calculated using a meta-analysis software. Results: A tendency toward more invasive treatment was observed for the clinical scenario with carious-exposed pulp (RR = 2.86, 95% CI: 2.46, 2.32; P < .001) as opposed to the clinical scenario with 2 pulp exposures (RR = 1.38, 95% CI: 1.24, 1.53; P < .001). Complete caries removal was significantly preferred to selective caries removal (RR = 4.59, 95% CI: 3.70, 5.69; P < .001). Among the capping materials, calcium silicate-based materials were preferred over calcium hydroxide-based materials (RR = 0.58, 95% CI: 0.44, 0.76; P < .05). Conclusions: While carious-exposed pulp is the most important factor in clinical decisions regarding DPC, the number of exposures has the least impact. Overall, complete caries removal was preferred over selective caries removal. In addition, the use of calcium silicate-based materials appears to have replaced calcium hydroxide-based materials.

The aim of this study was to determine how dental student self-assessment and faculty assessment of operative preparations compared for conventional visual assessment versus assessment of scanned digital 3D models. In 2016, all third-year students in the Class of 2018 (N=35) at Harvard School of Dental Medicine performed preclinical exams of Class II amalgam preparations (C2AP) and Class III composite preparations (C3CP) and completed self-assessment forms; in 2017, all third-year students in the Class of 2019 (N=34) performed the same exams. Afterwards, the prepared typodont teeth were digitally scanned. Students self-assessed their preparations digitally, and four faculty members graded the preparations conventionally and digitally. The results showed that, overall, the students assessed their preparations higher than the faculty assessments. The mean student-faculty gaps for C2AP and C3CP in the conventional assessments were 11% and 5%, respectively. The mean digital student-faculty gap for C2AP and C3CP were 8% and 2%, respectively. In the conventional assessments, preclinical performance was negatively correlated with the student-faculty gap (r=-0.47, p

Background:Correction of deformity using guided growth with plate and screw constructs has shown good results in the correction of angular deformities in children. Some recent reports have shown device failure, perhaps because of increased patient weight as seen in Blount disease. The purpose of our

Purpose: Microtubules play a critical role in many cellular functions, including cell division and mitosis. ABT-751 is a novel sulfonamide antimitotic that binds to the colchicine site on β-tubulin that leads to a block in the cell cycle at the G2M phase, resulting in cellular apoptosis. ABT-751 was investigated in this phase 1 trial designed to assess its maximum tolerated dose (MTD), dose-limiting toxicity (DLT), tolerability, and pharmacokinetics. Experimental Design: ABT-751 was administered on a daily (q.d.) or twice daily (b.i.d.) oral schedule for 7 days every 3 weeks to 39 patients with refractory solid tumors. Toxicity was monitored weekly. Plasma and urine ABT-751 and metabolite pharmacokinetics were determined. Results: The MTD for the q.d. schedule was 250 mg/d. DLTs during cycle 1 were abdominal pain, constipation, and fatigue. The MTD on the b.i.d. schedule was 150 mg. Cycle 1 of therapy with the 175 mg b.i.d. schedule was tolerated without DLT. However, six of seven patients reported grade 3 toxicity (ileus, constipation, abdominal pain, or fatigue), which occurred in cycle 2 or 3. ABT-751 was absorbed after oral administration with an overall mean Tmax of about 2 hours. The pharmacokinetics of ABT-751 were dose-proportional and time-independent. There was minimal accumulation of ABT-751 after multiple q.d. and b.i.d. doses. Efficacious concentrations, as determined from preclinical models (0.5-1.5 μg/mL), were achieved in all subjects. ABT-751 metabolism occurred primarily by glucuronidation and sulfation. No complete or partial tumor responses were noted, but one patient had a minor response, and four patients had stable disease lasting at least 6 months. Conclusions: The MTD and recommended phase 2 doses for ABT-751 were 250 mg q.d. and 150 mg b.i.d. on a 7-day schedule given every 3 weeks, due to subsequent cycle toxicities at 175 mg b.i.d. dosing. Toxicities were abdominal pain, constipation, and neuropathy.

This paper presents the technical reasoning and justification for using the B2′ = (2/3)*B2 in Paragraphs NB-3656(b) and NC/ND-3655(b) of Section III. ASME revised the rules for piping subjected to seismic and other building filtered loads in the 1994 addenda to the 1992 Code to provide an alternative to the existing rules. The purpose of the revision was to recognize the results of significant testing and experience that supported a decrease in the multiplier (B index) of the moment term, among other changes. The use of a B2′ index set equal to 2/3 of the current B2 index effectively raised the Level D allowable 50%. As part of its review in 10CFR50.55a, the NRC noted that use of the new rules was not permitted, due to disagreements in the approach. Since the 1994 addenda were published, the NRC and ASME have worked together to revise the changes. At this time, it is ASME’s understanding that the rules proposed for inclusion in the 2007 Code will be accepted by the NRC, with the exception of the use of a B2′ index equal to 2/3 of B2 for bends and tees. For those items, the NRC believes a multiplier of 3/4 is more appropriate for ferritic steels at temperatures above 300°F, due to dynamic strain aging. Concern has been expressed that since the tests that form part of the basis for setting B2′ = (2/3)*B2 were conducted at ambient temperature, the effect of dynamic strain aging of carbon steels could reduce the seismic margins at temperatures in excess of 300°F (150°C). In response to this concern, the authors prepared this paper as a team working under the Piping Seismic Task Group, ASME Code Committee. This paper demonstrates that: 1) In order to investigate this possibility, authors collected test data at room temperature, and then benchmarked its analytical work against both its tests and data from the EPRI test program since dynamic testing of components at elevated temperature and high stress levels can be quite difficult. From its analytical and test work on components, plus elevated temperature and strain rate work on small specimens, it was concluded that strain rate effects at typical seismic strain rates and amplitudes are not a concern. 2) For typical carbon steel under seismic strain rate loading, at elevated temperature [(above 300°F (150°C)] and at stress levels permitted by the alternative Code equation [NB-3556(b)(2) and NB-3556(b)(3)], the margin to failure is at least 1.5, as recommended by Dr. R.P. Kennedy(1). Thus, the use of B2′ = (2/3)*B2 results in a component with acceptable margin. This is a part of the paper prepared as a team working under the Piping Seismic Task Group under ASME Sec. III, Subgroup Design.Copyright © 2009 by ASME