Radiographs are an integral component of a periodontal assessment for those with clinical evidence of periodontal destruction. A close consideration of the current approach to periodontal diagnosis compatible with the current classification of periodontal diseases reveals that radiographs only inform with respect to diagnosis for a small proportion of conditions. The area in periodontal assessment in which radiographs play a pivotal role is in treatment planning. A variety of radiographic exposure types assist in the development of periodontal treatment plans. This ''therapeutic yield'' can be achieved by panoramic oral radiographs supplemented by selective intra-oral views. Digital panoramic oral radiographs viewed on screen appear to offer advantages over printouts or films. Newer imaging approaches, such as cone-beam computed (digital volume) tomography, may come to show some usefulness but experience has shown that digital subtraction radiography will probably remain a research tool without much clinical application.

IntroductionThe aim of this study was to assess if the complex anatomy of aortic aneurysm and aortic dissection can be accurately reproduced from a contrast‐enhanced computed tomography (CT) scan into a three‐dimensional (3D) printed model.MethodsContrast‐enhanced cardiac CT scans from two patients were post‐processed and produced as 3D printed thoracic aorta models of aortic aneurysm and aortic dissection. The transverse diameter was measured at five anatomical landmarks for both models, compared across three stages: the original contrast‐enhanced CT images, the stereolithography (STL) format computerised model prepared for 3D printing and the contrast‐enhanced CT of the 3D printed model. For the model with aortic dissection, measurements of the true and false lumen were taken and compared at two points on the descending aorta.ResultsThree‐dimensional printed models were generated with strong and flexible plastic material with successful replication of anatomical details of aortic structures and pathologies. The mean difference in transverse vessel diameter between the contrast‐enhanced CT images before and after 3D printing was 1.0 and 1.2 mm, for the first and second models respectively (standard deviation: 1.0 mm and 0.9 mm). Additionally, for the second model, the mean luminal diameter difference between the 3D printed model and CT images was 0.5 mm.ConclusionEncouraging results were achieved with regards to reproducing 3D models depicting aortic aneurysm and aortic dissection. Variances in vessel diameter measurement outside a standard deviation of 1 mm tolerance indicate further work is required into the assessment and accuracy of 3D model reproduction.

The aim of this study is to compile a comprehensive database on color range and color distribution of healthy human gingiva by age, gender and ethnicity. Spectral reflection of keratinized gingiva at upper central incisors was measured by spectroradiometer and converted into CIELAB values. Lightness range (ΔL*) for all groups together was 26.8. Corresponding a* (green-red) and b* (blue-yellow) ranges (Δa* and Δb*) were 18.3 and 13.0. Significant differences (p < 0.05) were recorded by age for L* and a* coordinates, by gender for b* coordinate, and by ethnicity for L*, a* and b* coordinates. R2-values between color coordinates were 0.01 (L*/a*), 0.03 (L*/b*), and 0.12 (a*/b*). The smallest color differences were recorded between age groups 46–60 and 60 + (ΔE* = 0.9), and between Caucasians and Hispanics (ΔE* = 1.1). Color difference by gender was 1.3. When total L*a*b* ranges were divided into four equal segments, 51.7% of subjects had L* value within the third segment (from lightest to darkest), 47.1% had a* value within the third segment (from less red to redder), and 59.3% had b* value within the second segment (from less yellow to yellower). It was found that ethnicity and age had statistically significant influence on the color of human gingiva.

Background/Purpose Although much has been written about the medical learning environment, the patient, who is the focus of care, is rarely the focus in this literature. The purpose of this study was to explore the role of the patient as an active participant with agency in the medical learning environment from the standpoint of the learner, the attending physician, and most importantly, the patient. We hoped to gain insights into the mechanisms that can reinforce professional values such as patient‐centred and respectful behaviours in a patient‐present learning environment. Methods We conducted this study in an ambulatory internal medicine clinic using ‘patient‐present’ clinic visits. All case presentations occurred in examination rooms with the patient. We invited participants (attending physicians, undergraduate and postgraduate learners, patients and family members) to participate in semistructured interviews after each clinic visit to explore the impact of the patient‐present learning environment. We recruited 34 participants in the study; 10 attending physicians, 12 learners, 10 patients and 2 family members. We analysed the data deductively using a conceptual framework of agency. Summary/Results We identified three major insights: (1) Patients felt engaged and valued opportunities to be heard; (2) Attending physicians and learners reported a more respectful learning environment and a positive though challenging teaching and learning experience; and (3) A hidden curriculum emerged in a performance‐based view of professional behaviour. Conclusions Patient‐present teaching engaged patients and enhanced their agency by recasting the patient as the central focus within the healthcare encounter. We identified a tension between performing and learning. This study adds new insights to the concept of patient centredness and professionalism from the perspectives of all participants in the medical teaching and learning environment.

Visuomotor adaptation to novel environments can occur via non-physical means, such as observation. Observation does not appear to activate the same implicit learning processes as physical practice, rather it appears to be more strategic in nature. However, there is evidence that interspersing observational practice with physical practice can benefit performance and memory consolidation either through the combined benefits of separate processes or through a change in processes activated during observation trials. To test these ideas, we asked people to practice aiming to targets with visually rotated cursor feedback or engage in a combined practice schedule comprising physical practice and observation of projected videos showing successful aiming. Ninety-three participants were randomly assigned to one of five groups: massed physical practice (Act), distributed physical practice (Act+Rest), or one of 3 types of combined practice: alternating blocks (Obs_During), or all observation before (Obs_Pre) or after (Obs_Post) blocked physical practice. Participants received 100 practice trials (all or half were physical practice). All groups improved in adaptation trials and showed savings across the 24-h retention interval relative to initial practice. There was some forgetting for all groups, but the magnitudes were larger for physical practice groups. The Act and Obs_During groups were most accurate in retention and did not differ, suggesting that observation can serve as a replacement for physical practice if supplied intermittently and offers advantages above just resting. However, after-effects associated with combined practice were smaller than those for physical practice control groups, suggesting that beneficial learning effects as a result of observation were not due to activation of implicit learning processes. Reaction time, variable error, and post-test rotation drawings supported this conclusion that adaptation for observation groups was promoted by explicit/strategic processes.