Search

This case report illustrates the successful nonsurgical treatment of an adult with a skeletal Class III malocclusion exacerbated by a functional anterior shift that resulted in a severe overclosure of the mandible and a reverse smile line. To maximize the soft tissue and smile esthetics while idealizing the occlusion, active clockwise rotation of the mandible was induced along with mandibular molar uprighting and sequential leveling. In the maxilla, full arch distalization was achieved after second molar extraction. The treatment provided a satisfying esthetic and functional outcome and has remained stable.

The Transient Reactor Test (TREAT) Facility provided thousands of transient irradiations and plays a crucial role in nuclear-heated safety research. The facility’s flexible design and multi-mission nature saw historic experiments for numerous reactor fuels and transient types but was never specifically adapted to address very-brief pulse transients akin to postulated Light Water Reactor (LWR) Reactivity Initiated Accidents (RIA). Since the behaviors of fuel under these conditions depends strongly on energy input duration and resulting cladding time/temperature response under pellet cladding mechanical interactions, this three-year project was conceived to investigate new pulse-narrowing capabilities. Kinetic models showed incremental improvements for minor facility enhancements including increased reactivity step insertions (to initiate the power pulse) and slightly-increased transient rod drive speed for pulse termination (“clipping”). Replacing peak fuel assemblies, repositioning non-transient control rods to hold down the “hot side” of the core, and balancing against required excess reactivity needs, the limiting fuel assembly power can be reduced by ∼20%. This is a remarkable discovery of latent capability in TREAT, not only in enabling the subject capabilities for reduced pulse widths, but also significantly “uprating” the core’s transient energy capacity. Incremental improvements can likely enhance TREAT’s capability into BWR-relevant missions; briefer PWR pulse shapes can only be achieved with an advanced clipping system. Helium-3 (3He) was found to offer the greatest benefits for clipping design and overall performance. A unique concept showed great promise for enabling a 3He-based system with a reasonable cost; this design concept will likely become the focal point of future work.

The use of 3D technology in orthodontics has increased recent years. 3D intra-oral scanning, cone beam computed tomography (CBCT), 3D printing and computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been utilized to create “personalized” orthodontic appliances. While technological improvements to orthodontic appliances seem promising, do they truly improve treatment efficiency and/ or treatment quality? This article will review currently available orthodontic appliances which utilizes 3D technology such customized wires and CAD/CAM fabricated brackets. Customized archwires are planned from 3D virtual setup and robotically bent. Studies have shown a decrease in treatment time with the use of customized wires, however data on quality of treatment results are conflicting. While this technology is fairly accurate for mesial-distal tooth movements, it is less precise for crown tip and root torque. CAD/CAM brackets were initially shown to be more effective and efficient when compared to standard brackets, but a follow-up study showed no difference in the quality of treatment of outcomes. The study also showed the majority of the reduction in treatment time resulting from CAD/CAM brackets may be due to the indirect bonding process rather than the personalized milled slots.

Introduction The characteristics of patients who seek and accept orthognathic surgery appear to be changing over time but have not been well documented in the 21st century. Methods Records for patients who had orthognathic surgery at the University of North Carolina from 1996 to 2000 and from 2006 to 2010 were reviewed to collect data for changes in the prevalence of patients with mandibular deficiency (Class II), maxillary deficiency or mandibular prognathism (Class III), long face, and asymmetry problems. The changes were compared with those in previous time periods and at other locations. Results Between 1996 and 2000 and between 2006 and 2010, the percentage of Class III patients increased from 35% to 54%, and the percentage of Class II patients decreased from 59% to 41%, while the percentages for long face and asymmetry showed little change. The decrease in Class II patients was accentuation of a long-term trend; the increase in Class III patients occurred only after the turn of the century. Conclusions A similar but less-marked change has been noted at some but not all other locations in the United States. It appears to be related primarily to an increase in the numbers of African Americans, Native Americans, Hispanics, and Asians who now are seeking surgical treatment, but it also has been affected by changes in where orthognathic surgery is performed, decisions by third-party payers (insurance and Medicaid) about coverage for treatment, and the availability of nonsurgical orthodontic treatment options for Class II patients.