DZZ International, 06/2022

Introduction: The aim of this in vitro study was to investigate the influence of different scan paths on the accuracy of digital full arch impressions obtain - ed by 3 scanning systems. Materials and methods: A maxillary model with 14 prepared teeth was digitized with a reference scanner (ATOS III Triple Scan) and 3 test scanners (CS 3500, CEREC Omnicam and True Definition) using 7 different scan paths. In test path 1 and 2, the manufacturers’ suggested scan paths were investigated. In test path 3, 4, and 5 shorter scan paths were utilized. For comparison, a randomly selected scan path was performed in test path 6. Test path 7 was a repetition of scan path 1 to investigate whether there was a learning effect. The scans were digitally superimposed (Geomagic Control), values for trueness and precision were evaluated and statistical analyses performed. Results: Path 4 (trueness: 32.7 ± 10.3 μm, precision: 23.8 ± 9.5 μm) and path 5 (trueness: 35.1 ± 10.7 μm, precision: 24.2 ± 10 μm) revealed the highest accuracy. For trueness measurements of Omnicam, no statistically significant differences were found between individual scan paths. Overall, path 7 showed a higher accuracy than path 1, however, the differences were not statistically significant. Conclusion: Ideally, the selected scan path should be as short as possible, and long-distance scans should be avoided. The accuracy of Omnicam appeared not to be dependent on a specific scan path. For all three scanners, the accuracy was clinically acceptable, however, the scan of a prepared full arch with a point-and-click system (CS 3500) cannot be recommended. Parole chiave: computerized optical impression making, digital impression, optical impression, scan path; scan pattern

Introduction: Instruction on interdental cleaning at home (IC) is daily routine in the dental practice and mostly performed by dental professionals (DP). Recently published S3-guidelines (AWMF: 083–022/083–043) describe, among other things, the need and extent of patient-specific instructions on IC. However, since little evidence is available up to date regarding the DP’s recommendations to patients on IC or data on the level of knowledge of German DPs about IC, an exploratory survey study was initiated. Methods: At 2 evaluation time points in 2018 and 2021 (during and after the publication of guideline AWMF: 083–022/083–043), dental professionals with (DP+) and without (DP–) certified education in dental hygiene were surveyed at 3 German dental training institutes using an anonymized and validated online questionnaire (unipark.com, Tivian XI GmbH, Cologne, Germany). The probands answered 11 questions regarding personal details (including age, professional degree/experience, personal IC habits), the recommendations according to IC (including devices such as interdental brush/floss and additional use of toothpaste or interdental gel together with the IC devices), and the basis for their recommendations. The results were analyzed mainly descriptively. Results: In total, 89 DPs participated in 2018 (DP–/DP+: 68/21) and 109 DPs in 2021 (DP–/DP+: 59/50), 2021 with a higher DP+ rate (p = 0.006). At both evaluation times, DP+ were more likely (2018/2021: 62 %/64 %) to report following scientific recommendations than DP– (2018/2021: 27 %/41 %). At the first evaluation date, 78 % of all DPs (2021: 73 %) reported recommending IC devices they themselves perceived as effective. Patient preferences were considered by DP+ 24 % in 2018 and 36 % in 2021. DP– considered patient preferences in 54 % (2018) and 39 % (2021). DPs predominantly reported to use interdental brushes (2018/2021: 75 %/77 %) and floss (2018/2021: 78 %/84 %) as their personal IC devices. A majority of DPs also recommended both devices in 2018/2021 with 99 %/95 % for interdental brushes and 75 %/78 % for floss. Discussion: Despite the small number and special selection of DPs, the results of the exploratory survey study suggest that a basic knowledge of IC is present in all groups of DPs. The DPs surveyed were more likely to consider the selfperceived efficacy of IC devices than patient preferences or evidence-based recommendations, regardless of their level of certification. Conclusion: The results suggest that there is a need for more intensive coaching of DPs regarding evidence-based and patient-specific instruction on IC at home. Parole chiave: dental hygienist, dental professional, instruction, interdental cleaning at home

Introduction: To this day, the name Eugen Fröhlich stands for successful work in science and professional politics. But what was his influence on the development of dentistry and what was his relationship to National Socialism? These are precisely the questions that this article explores. Material and methods: The study is based, among others, on primary documents of the State Archives Baden-Württemberg as well as the University Archives and the University Library of Tübingen. In addition, sources from the Federal Archives in Berlin were evaluated. Furthermore, a comprehensive analysis of publications by and about Fröhlich was carried out. Results: Fröhlich left clear traces on the institutional, professional-political and scientific level: In Tübingen he had a decisive influence on the new clinic building completed in 1968 and the reorganisation of the clinic structures, and in Ulm, he initiated the establishment of today’s University Dental Clinic. He was active in professional politics as chairman of the ARPA (Working Group on Periodontology), the “Zahnärztliche Dozentenvereinigung“ (Association of Lecturers in Dentistry) and the “Deutsche Gesellschaft für Zahn-, Mund- und Kieferheilkunde” (German Society for Dental and Oral Medicine, DGZMK), and he made scientific contributions to oral surgery, prosthodontics and periodontology. In the Third Reich Fröhlich was a member of the NSDAP (National Socialist German Workers’ Party) and the SA (Storm Department), among others. Discussion and conclusion: Fröhlich is to be regarded as an important promoter of the institutional development of university dentistry: He initiated the new clinic building in Tübingen and prompted the establishment of several independent chairs in dentistry, thus becoming a model for other locations. Through his visible work in ARPA, he also brought the subject of periodontology into focus, and with the introduction of the term “dysgnathia” he set himself a professional monument. Fröhlich’s political role in the Third Reich was that of a follower. After 1945, however, he tried to construct a distance to National Socialism by means of half-truths and whitewashing. Parole chiave: ARPA, DGZMK, dysgnathia, National Socialism, Tübingen

Introduction: For many dentists, the name Rudolf Naujoks stands for topclass basic research and professional-political commitment. The present article takes this positive but general image as an opportunity to highlight Naujoks’ concrete influence on the development of dentistry; a further focus is on his relationship to National Socialism. Material and methods: The methodological basis of the study are files from the Hamburg State Archive. In addition, research was conducted at the Berlin Federal Archives. The scientific publications of Naujoks and the secondary literature available on his person were evaluated as further sources. Results: Naujoks was one of the most sustainable modernizers of German dentistry in the second half of the century. During his term of office as president of the German Society for Dental and Oral Medicine (DGZMK), the “Akademie Praxis und Wissenschaft” (Academy Practice and Science, APW, 1974) and various working groups were established, which significantly promoted the further development of the DGZMK and beyond. His scientific achievements included innovative research on caries prophylaxis and fluoridation. There were no indications of a political connection to National Socialism. Discussion and conclusion: Compared to his predecessors, Naujoks had specific characteristics and approaches: These relate to his educational path, his understanding of dentistry, his research approach, his publication practice, his vision with regard to the DGZMK and his political orientation. These characteristics show that Naujoks initiated a far-reaching paradigm shift both within the DGZMK and within university dentistry. Parole chiave: APW, cariology, DGZMK, fluoridation, National Socialism

Introduction: Werner Ketterl is one of the most successful university teachers of the recent past. Since the 1960s, he has had a lasting influence on the development of university dentistry as a scientist and professional politician. In addition, he was one of the few protagonists of the discipline who dealt with National Socialism in autobiographical memoirs. Against this background, this article focusses on the life and work of the Mainz professor in the Third Reich and the Federal Republic of Germany. Material and methods: The central basis of the study are, among others, primary sources from the Federal Archives Berlin and the State Archives Munich as well as Ketterl’s autobiography from 2000. In addition, a comprehensive analysis of professional publications by and about Ketterl was carried out. Results: Werner Ketterl was probably the most influential specialist representative in the field of Restaurative Dentistry, especially in the 1970s and 1980s – alongside Adolf Kröncke and Rudolf Naujoks. However, he was more clinically oriented in research than the aforementioned colleagues and he also developed a stronger focus on periodontology. In the Third Reich he showed himself to be loyal to the regime. He applied for membership in the NSDAP (National Socialist German Workers’ Party) in the month of his 18th birthday and was accepted three months later. Discussion and conclusion: Ketterl understood dentistry as a unity of science and professional policy. With this symbiotic approach, he shaped the development and the public perception of dentistry like hardly any other university lecturer of his time – both at the University of Mainz and on a national scale. However, his commitment to the NSDAP is beyond the expected – especially in view of the fact that he concealed his party membership in his memoirs and, moreover, frankly discredited the supporters of National Socialism. Parole chiave: tooth preservation, periodontology, Mainz, NSDAP, National Socialism