Euler-angle norms for tooth rotation, torque and tip.

INTRO: The aim of the current study was to develop and describe a new measuring system for the orientation of a tooth in a digitalized cast of a jaw and provide new angular values for the rotation, torque and tip of maxillary and mandibular teeth. METHODS: This retrospective cross-sectional study involved the utilization of a sub-group of extrinsic Euler-angles to derive optimal norm values per tooth in three different planes of orientation ('rotation', 'torque' and 'tip') by evaluating the digital representations of the teeth derived from a database containing over 17,500 patients. The process involved the entry of the .stl files of the jaw pairs into a fully automated software system (Smyl:Ai, Ulm, Germany) whereupon jaw alignment, teeth segmentation, landmark identification and visual validation of input files was conducted prior to calculation of the norm values for the three different planes of orientation. RESULTS: The digital scans in stereolithography (.STL)-file format of the upper and lower dentitions of 1914 individuals with optimal occlusion were chosen and evaluated. New mean (standard deviation) angular values were determined for the rotation, torque and tip of maxillary and mandibular teeth. CONCLUSION: The findings facilitate the reappraisal of rotation, torque and tip values currently acceptable as ideal. They will inform anthropologists and dental researchers about occlusion and alignment in orthodontic and non-orthodontic patients and provide baseline data for future studies. The methodology will also enable the evaluation of large numbers of data in relatively short timeframes.

[The specialist skills of the nurse in hemodialysis: report of an explorative survey. A challenge for professional recognition].

Nursing requires a complex set of skills encompassing professional clinical judgment, values and attitudes. In order to outline the future career path of the specialist nurse, the European Federation of Nurses Association compared the EU Directive 2013/55/EU with the Competency Framework, an important document on guidelines written by a group of experts and focusing on the recognition of nurses' educational requirements. The aim of our research is to identify the special skill set required from nurses on haemodialysis wards through the development of an exploratory survey and the comparison of its results with the EFN guidelines and the Directive 2013/55/EU. The survey was conducted across eighteen dialysis centers in Tuscany. Through focus groups, debates and reflections, 28 skills were identified as pertaining exclusively to nurses working with haemodialysis patients. This preliminary study aims at demonstrating the need to define and recognize these specialist skills in order to ensure an effective and integrated nursing leadership in disease management.