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OBJECTIVE The aims of this study were (1) to investigate how relevant intraoral photographs are to contemporary orthodontic diagnosis and (2) to assess orthodontists' ability to accurately diagnose angle classification and dental midlines using standardized intraoral photographs. METHODS Study participants were orthodontists who completed a survey regarding photography protocols and their use of intraoral photographs for diagnosis. Each participant was randomized to complete 1 visual diagnostic task regarding either angle classification or midlines. Accuracy was compared across groups and camera angulations. RESULTS In all, 80% of 192 respondents reported using photographs and clinic notes to plan orthodontic treatment; 50% also included dental casts. For the angle task, accuracy judging molar and canine classification was 79.9% and 51.3%, respectively with ideal standardized photographs. As camera angulation deviated, accuracy decreased significantly (P

The Five Minute Intervention (FMI) project trained prison officers to turn everyday conversations into rehabilitative opportunities using skills such as Socratic questioning, active listening, and affirmation. Webster and Kenny (2015) reported on the experiences of prison officers involved in the FMI pilot. This research reports on the experiences of ten male prisoners who participated in FMI conversations with prison officers. FMI training now forms part of the national training programme for prison staff.

Introduction The aims of this study were to identify stable mandibular structures in 3 dimensions in growing patients using a regional implant technique and to test the reproducibility of mandibular regional superimposition in 3 dimensions using the regions identified. Methods Three-dimensional voxel-based regional mandibular registrations were performed on bone plates, and screws were placed in the anterior chin and symphysis regions of 20 growing patients (mean age, 12.1 ± 1.3 years). Three-dimensional models of the resulting superimpositions were built for the chin, symphysis, and third molar crypts. Absolute mean errors were calculated for each region to evaluate stability. Longitudinal cone-beam computed tomography scans were obtained of 25 patients (mean age, 12.7 ± 1.4 years) with different skeletal malocclusions (20 Class II, 5 Class III). To evaluate reliability of mandibular registrations using the chin and symphysis regions, voxel-based superimpositions were performed independently by 2 observers. The resulting superimpositions between the 2 examiners were overlaid, and the mean difference along the entire surface of the mandible was calculated. Results The chin and symphysis regions showed high levels of precision (chin absolute mean error, 0.37 ± 0.16 mm; symphysis absolute mean error, 0.4 ± 0.15 mm). The third molar region had a high registration error (absolute mean error, 1.94 ± 0.06 mm). The voxel-based registrations using the chin and symphysis were reliable and reproducible between examiners (absolute mean error, 0.12 ± 1.1 mm). Intraclass correlation coefficient results showed a high degree of agreement between examiners. Conclusions The chin and symphysis regions are stable areas for 3-dimensional mandibular regional superimpositions.

Animal models are important tools for studies of human disease, but developing these models is a particular challenge with regard to organisms with restricted host ranges, such as the human stomach pathogen Helicobacter pylori . In most cases, H. pylori infects the stomach for many decades before symptoms appear, distinguishing it from many bacterial pathogens that cause acute infection. To model chronic infection in the mouse, a human clinical isolate was selected for its ability to survive for 2 months in the mouse stomach, and the resulting strain, MSD132, colonized the mouse stomach for at least 28 weeks. During selection, the cagY component of the Cag type IV secretion system was mutated, disrupting a key interaction with host cells. Increases in both bacterial persistence and bacterial burden occurred prior to this mutation, and a mixed population of cagY + and cagY mutant cells was isolated from a single mouse, suggesting that mutations accumulate during selection and that factors in addition to the Cag apparatus are important for murine adaptation. Diversity in both alleles and genes is common in H. pylori strains, and natural competence mediates a high rate of interstrain genetic exchange. Mutations of the Com apparatus, a membrane DNA transporter, and DprA, a cytosolic competence factor, resulted in reduced persistence, although initial colonization was normal. Thus, exchange of DNA between genetically heterogeneous H. pylori strains may improve chronic colonization. The strains and methods described here will be important tools for defining both the spectrum of mutations that promote murine adaptation and the genetic program of chronic infection.

All organisms have pathways that repair the genome, ensuring their survival and that of their progeny. But these pathways also serve to diversify the genome, causing changes at the nucleotide, whole gene, and genome structure levels. Sequencing of bacteria has revealed wide allelic diversity and differences in gene content within the same species, highlighting the importance of understanding pathways of recombination and DNA repair. The human stomach pathogen Helicobacter pylori is an excellent model system for studying these pathways. H. pylori harbors major recombination and repair pathways and is naturally competent, facilitating its ability to diversify its genome. Elucidation of DNA recombination, repair, and diversification programs in this pathogen will reveal connections between these pathways and their importance to infection.

The purpose of our study was to evaluate the effectiveness of self-tests as a component of web-based self-instruction in predoctoral orthodontics and pediatric dentistry. To this end, the usage patterns of online teaching modules and self-tests by students enrolled in three courses at the University of North Carolina at Chapel Hill School of Dentistry were monitored and correlated to final exam grade and course average. We recorded the frequency of access to thirty relevant teaching modules and twenty-nine relevant self-tests for 157 second- and third-year D.D.S. students during the course of our data collection. There was a statistically significant positive correlation between frequency of accessing self-tests and course performance in one course that was totally based on self-instruction with seminars and multiple-choice examination (Level IV): Spearman correlation between frequency of self-test access and final exam grade, rho=0.23, p=0.044; correlation between frequency of self-test access and course average: rho=0.39, p=0.0004. In the other two courses we monitored, which included content beyond self-instruction with self-tests, the correlations were positive but not statistically significant. The students' use of online learning resources varied significantly from one course (Level I) to the next (Level II): Wilcoxon matched pairs signed-rank tests, S=-515.5, p=.0057 and S=1086, p

Assessing facial symmetry is an evolutionarily important process, which suggests that individual differences in this ability should exist. As existing data are inconclusive, the current study explored whether a group trained in facial symmetry assessment, orthodontists, possessed enhanced abilities. Symmetry assessment was measured using face and non-face stimuli among orthodontic residents and two control groups: university participants with no symmetry training and airport security luggage screeners, a group previously shown to possess expert visual search skills unrelated to facial symmetry. Orthodontic residents were more accurate at assessing symmetry in both upright and inverted faces compared to both control groups, but not for non-face stimuli. These differences are not likely due to motivational biases or a speed-accuracy tradeoff—orthodontic residents were slower than the university participants but not the security screeners. Understanding such individual differences in facial symmetry assessment may inform the perception of facial attractiveness.

Introduction:Anaccurateassessmentoffacesymmetryisnecessaryforthedevelopment ofadentofacial diagnosis in orthodontics, and an understanding of individual differences in perception of face symmetry between patients and providers is needed to facilitate successful treatment. Methods: Orthodontists, general dentists, and control participants completed a series of tasks to assess symmetry. Judgments were made on pairs of upright faces (similar to the longitudinal assessment of photographic patient records), inverted faces, and dot patterns. Participants completed questionnaires regarding clinical practice, education level, and self-confidence ratings for symmetry assessment abilities. Results: Orthodontists showed expertise compared with controls (P\0.001), whereas dentists showed no advantage over controls. Orthodontists performed better than dentists, however, in only the most difficult face symmetry judgments (P 5 0.006). For both orthodontists and dentists, accuracy increased significantly when assessing symmetry in upright vs inverted faces (t 5 3.7, P 5 0.001; t 5 2.7, P 5 0.02, respectively). Conclusions: Orthodontists showed expertise in assessing face symmetry compared with both laypersons and general dentists, and they were more accurate when judging upright than inverted faces. When using accurate longitudinal photographic records to assess changing face symmetry, orthodontists are likely to be incorrect in less than 15% of cases, suggesting that assistance from some additional technology is infrequently needed for diagnosis. (Am J Orthod Dentofacial Orthop 2013;144:663-71)

The 2013 nesting season was the second year comparing the Peterson box to the traditional rectangular blue bird nesting box. Peterson boxes have a lower internal volume, requiring less material and parental effort for nest construction. It has been suggested that by freeing up energy for rearing young, fledging success could be improved over that of the traditional box. As during the previous season, bluebirds, tree swallows and chickadees utilized the Peterson boxes. However, unlike the 2012 season, more nests were built in Peterson boxes than in the traditional boxes. Of the 11 nests built in Peterson boxes, eggs were laid in 8 boxes of which only 4 successfully fledged chicks. Eggs or chicks were lost to predators from 3 of the Peterson boxes, while one clutch of 3 chicks was found dead in the nest. Five nests were built in traditional boxes, of which three fledged chicks. Hatching and fledging success were higher for eggs laid in traditional boxes than in the Peterson boxes. However, the paucity of clutches (2 of the 3 clutches in traditional boxes were in the same box) makes it difficult to draw a conclusion about hatching of fledging success. Student volunteers from both the general biology and human anatomy and physiology classes at Mountain Empire Community College assisted in the monitoring of nesting activity during the course of the breeding season, as well as maintenance along the trail.

The purpose of our study was to evaluate the effectiveness of self-tests as a component of web-based self-instruction in predoctoral orthodontics and pediatric dentistry. To this end, the usage patterns of online teaching modules and self-tests by students enrolled in three courses at the University of North Carolina at Chapel Hill School of Dentistry were monitored and correlated to final exam grade and course average. We recorded the frequency of access to thirty relevant teaching modules and twenty-nine relevant self-tests for 157 second- and third-year D.D.S. students during the course of our data collection. There was a statistically significant positive correlation between frequency of accessing self-tests and course performance in one course that was totally based on self-instruction with seminars and multiple-choice examination (Level IV): Spearman correlation between frequency of self-test access and final exam grade, rho=0.23, p=0.044; correlation between frequency of self-test access and course average: rho=0.39, p=0.0004. In the other two courses we monitored, which included content beyond self-instruction with self-tests, the correlations were positive but not statistically significant. The students' use of online learning resources varied significantly from one course (Level I) to the next (Level II): Wilcoxon matched pairs signed-rank tests, S=-515.5, p=.0057 and S=1086, p0.0001. The data from this study suggest that increased use of web-based self-tests may be correlated with more effective learning in predoctoral dental education by virtue of the testing effect and that dental students' usage of resources for learning changes significantly over the course of their education.

Professionals whose careers depend on visual skills typically demonstrate superior performance on career-related tasks; farmers better determine the sex of day-old chicks (Biederman & Shiffrar, 1987), and bank tellers better detect counterfeit currency (Klein, Gadbois, & Christie, 2004). Perceptual expertise has implications for learning and malleability, but the interpretation of expertise benefits is not straightforward. Complications arise, in part, because standard methodologies typically compare professionals to laypersons, raising concerns about confounding differences (e.g., motivation, speed/accuracy tradeoff, self-selection). Additionally, the mechanisms responsible for improvement may be ambiguous (e.g., enhanced sensory discrimination vs. improved strategies). To account for these issues, we analyzed performance across different professional groups on tasks related and unrelated to their careers. We assessed two groups of visual search experts (radiologists, airport security screeners), one group of facial symmetry experts (orthodontists), and one non-professional group (university participants). As expected, the professional groups demonstrated superior accuracy for career-related tasks (radiologists and airport security screeners for search, orthodontists for facial symmetry), and additional comparisons provided further insight. To evaluate potential differences in motivation, we compared performance on a task unrelated to the professionals’ expertise—temporal order judgment—and found no accuracy differences between professionals and non-professionals. Relatedly, comparisons between professional groups minimized speed/accuracy tradeoff concerns; professionals were slower on all tasks but only showed enhanced accuracy for career-relevant tasks. To elucidate whether benefits arose from self-selection or experience, we compared early- versus late-career individuals within the same profession and found differences related to amount of experience. Finally, we explored the nature of experts’ improvements and found evidence supporting superior top-down strategy selection (search professionals choose more effective strategies) as well as bottom-up stimulus-specific processing (orthodontists revealed enhanced symmetry discrimination for faces only). By comparing different types of experts on multiple tasks, we can better inform the nature of visual expertise.

We report on the application of low phonon-energy glasses doped with praseodymium. Radiative and non-radiative properties, as determined by experimental and theoretical techniques are presented, along with absorption and fluorescence spectra, and measured lifetimes.