Alexander Schmidt

Dr. Alexander Schmidt


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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9 October 2020 in BMC Medical Education
Verified
Journal Article
Open access
PDF file
Maximiliane SchlenzMaximiliane Schlenz
Maximiliane Schlenz
ASAlexander Schmidt
Alexander Schmidt
BWBernd Wöstmann
Bernd Wöstmann
NKNobert Krämer
Nobert Krämer
NSNelly Schulz-Weidner
Nelly Schulz-Weidner
Background: On account of physical distancing measures, universities worldwide are strongly affected by SARS-CoV-2 (COVID-19). Thus, the dental school of Justus-Liebig-University Giessen (Germany) transferred the established “face-to-face” learning to online learning in the spring term 2020. The aim of this study was to assess the students’ and lecturers’ perspectives on the implementation of online learning due to COVID-19, using a questionnaire survey. Methods: After the online period, all students and lecturers were asked to fill out an online questionnaire containing evaluative statements regarding handling, didactic benefit, motivation, and overall assessment. Furthermore, the questionnaire for lecturers contained additional aspects regarding knowledge gain in terms of providing online learning. Besides that, students and lecturers were asked for the amount of online learning in the future curriculum (independent of COVID-19). Data were subjected to regression analysis and T-test (p < .05). Results: 36.8% of students preferred “face-to-face” learning instead of sole online learning. An increase of know how concerning online teaching was observable for lecturers. Both, students and lecturers, want to keep up with online courses in the future curriculum. However, in terms of the optimal amount of online learning a significant difference between students’ and lecturers’ perspective was observed. While students suggested 53.2% (24.9) (mean (standard deviation)) lecturers only stated 38.6% (21.5). Conclusions: Within the limitation of this study, students’ and lecturers’ showed a predominantly positive perspective on the implementation of online learning, providing the chance to use online learning even beyond COVID-19 in the future curriculum.

1 December 2016 in Journal of Dentistry
Verified
Journal Article
Closed access
FKF. Kuhr
F. Kuhr
ASAlexander Schmidt
Alexander Schmidt
PRPeter Rehmann
Peter Rehmann
BWBernd Wöstmann
Bernd Wöstmann

Verified
Journal Article
Open access
PDF file
ASAlexander Schmidt
Alexander Schmidt
LKLeona Klussmann
Leona Klussmann
BWBernd Wöstmann
Bernd Wöstmann
Maximiliane SchlenzMaximiliane Schlenz
Maximiliane Schlenz
The aim of this clinical study was to update the available data in the literature regarding the transfer accuracy (trueness/precision) of four current intraoral scanners (IOS) equipped with the latest software versions and to compare these data with conventional impressions (CVI). A metallic reference aid served as a reference dataset. Four digital impressions (Trios3Cart, Trios3Pod, Trios4Pod, and Primescan) and one CVI were investigated in five patients. Scan data were analyzed using three-dimensional analysis software and conventional models using a coordinate measurement machine. The transfer accuracy between the reference aid and the impression methods were compared. Differences with p < 0.05 were considered to be statistically significant. Overall, mean ± standard deviation (SD) transfer accuracy ranged from 24.6 ± 17.7 µm (CVI) to 204.5 ± 182.1 µm (Trios3Pod). The Primescan yielded the lowest deviation for digital impressions (33.8 ± 31.5 µm), followed by Trios4Pod (65.2 ± 52.9 µm), Trios3Cart (84.7 ± 120.3 µm), and Trios3Pod. Within the limitations of this study, current IOS equipped with the latest software versions demonstrated less deviation for short-span distances compared with the conventional impression technique. However, for long-span distances, the conventional impression technique provided the lowest deviation. Overall, currently available IOS systems demonstrated improvement regarding transfer accuracy of full-arch scans in patients.

18 March 2020 in BMC Oral Health
Verified
Journal Article
Open access
PDF file
Maximiliane SchlenzMaximiliane Schlenz
Maximiliane Schlenz
KMKarin Michel
Karin Michel
KWKerstin Wegner
Kerstin Wegner
ASAlexander Schmidt
Alexander Schmidt
PRPeter Rehmann
Peter Rehmann
BWBernd Wöstmann
Bernd Wöstmann
Background: Digitalisation is an expanding field in dentistry and implementation of digital teaching methods in dental education is an essential part of modern education. Therefore, two digital training modules were implemented in the preclinical curriculum at the Justus Liebig University Giessen. The aim of this study was to assess the students’ perspective on the implementation with a questionnaire survey.Methods: Since the fall term 2017/18, students of the course of dental prosthodontics I attended the training module I, where they learned to use computer-aided learning (CAL) approaches for the digital analysis of tooth preparations. In training module II, students of the course of dental prosthodontics II learned how to manufacture a computer-aided design/computer-aided manufacturing restoration. After the completion of the training modules, all students starting with the fall term 2017/18 to the spring term 2019 were asked to fill in a questionnaire regarding the aspects of handling, didactic benefit, motivation, and overall assessment.Results: Students rated the implementation of digital aspects in teaching as positive in terms of handling, didactic benefit, and motivation, but gave preference to the assessment of the tooth preparations by dental instructors. In addition, students assessed the feedback from the faculty regarding tips and tricks better than the digital feedback. More than 90% of the students indicated that they could imagine using an intraoral scanner for treatment of patients in the dental office in future.Conclusions: The results of the present study revealed a positive perspective of students on the implementation of digital dentistry in the preclinical curriculum. However, difficulties with CAL systems were reported and most students preferred evaluation of preparation by dental instructors. Thus, CAL approaches offer an additional teaching method besides the traditional teaching of manual skills.

18 May 2022 in Clinical Oral Implants Research
Verified
Journal Article
Open access
ASAlexander Schmidt
Alexander Schmidt
BWBernd Wöstmann
Bernd Wöstmann
MSMaximiliane Amelie Schlenz
Maximiliane Amelie Schlenz
Objectives: The use of intraoral scanners (IOSs) for digital implant impressions in daily clinical practice is increasing. However, no structured literature review on the accuracy of digital implant impressions in clinical studies has been described to date. Therefore, this systematic review aimed to answer the PICO question: Which accuracy is described for digital implant impressions in clinical studies?Material and Methods: An electronic database search was conducted in December 2021 using MeSH terms and free‐text search. English‐language studies addressing the accuracy of digital implant impressions in clinical studies involving at least 10 patients were included. All clinical indications were considered.Results: Eight publications between 2014 and 2021 matched the review criteria. However, the study designs showed considerable differences. The number of implants within the studies ranged from 1 to 6, and the number of patients ranged from 10 to 39. The oldest study (2014) revealed the highest deviation for linear distances at 1000 ± 650 µm, whereas the other studies reported data in the range of 360 ± 46 µm to 40 ± 20 µm. In one study, no numerical data were reported and all studies compared digital and conventional implant impressions.Conclusions: The number of clinical studies on the accuracy of digital implant impressions is low. Thus, the impact of different factors, such as the scanpath or scanbody, could not be identified. However, the accuracy of recent IOSs for digital implant impressions in patients was shown to be clinically acceptable. Nevertheless, the transfer error still needs to be considered when fabricating implant‐supported restorations.

10 March 2022 in Sensors
Verified
Journal Article
Open access
PDF file
Maximiliane SchlenzMaximiliane Schlenz
Maximiliane Schlenz
BSBerenike Schupp
Berenike Schupp
ASAlexander Schmidt
Alexander Schmidt
BWBernd Wöstmann
Bernd Wöstmann
IBIngo Baresel
Ingo Baresel
NSNelly Schulz-Weidner
Nelly Schulz-Weidner
The aim of this in vitro study was to systematically investigate new caries diagnostic tools, including three intraoral scanners, and compare them to established diagnostic methods. For a standardized analysis of occlusal and proximal caries lesions, human permanent and primary teeth (n = 64) were embedded in models and investigated in a phantom head using six different caries diagnostic methods: visual examination, bitewing radiography, Diagnocam (KaVo, Biberach, Germany), Trios 4 (3Shape, Copenhagen, Denmark), iTero Element 5D (Align Technology, San José, CA, USA), and Planmeca Emerald S (Planmeca, Helsinki, Finland). The diagnostic methods were investigated and compared to reference µ-CT for permanent and primary teeth separately. For occlusal caries diagnostics in permanent teeth, the best agreement to the reference (reliability) was obtained for Planmeca Emerald S (ĸ = 0.700), whereas in primary teeth, for visual examination (ĸ = 0.927), followed by Trios 4 (ĸ = 0.579). Regarding proximal caries diagnostics, bitewing radiography, as the gold standard, exhibited the highest agreement for permanent (ĸ = 0.643) and primary teeth (ĸ = 0.871). Concerning the analysis of the diagnostic quality (sensitivity and specificity) using receiver operating characteristic (ROC) curve analysis, comparable findings were obtained for area under curve (AUC) values as for reliability. No diagnostic method could be identified that is generally suitable for occlusal and proximal lesions in both dentitions. Overall, caries diagnostics with intraoral scanners seem to be interesting tools that should be further investigated in clinical studies.