Aim: Even though today, many fields in dentistry allow digital processes, analogue procedures are still widely used. This cross-sectional pilot study aimed to survey insights on the digitalisation of dental practices using the example of Hesse. Materials and Methods: Between April and June 2022, 4840 active practicing dentists registered by the State Dental Association of Hesse were invited via e-mail to fill out an online questionnaire regarding their technical requirements in dental practice, dental treatment procedures, and attitude towards digitalisation in dentistry. Demographic questions were asked. Besides descriptive statistics, correlations were analyzed (P < 0.05). Result: Questionnaires of 937 dentists (279 female, 410 male, four inter/divers, 244 no answer; mean age of 51.4 ± 10.4 years) were examined representing a respond rate of 19.36%. In the area of practice administration and dental radiography, the majority of the dentists surveyed is already working digitally, which is predominantly assessed as a positive development. Already one third of the respondents state that they use an intraoral scanner for dental treatments, but the indication is mainly limited to smaller restorations. However, many dentists rate the use of social media accounts and telemedicine rather negative. Conclusion: Within the limitation of this pilot study, many processes especially in dental treatments are still analogue. However, 60% of the participants plan digitalisation of their dental practices within the next five years, which indicates a clear shift from analogue to digital dentistry. Keywords: Analog-Digital Conversion, CAD/CAM, Dental Practice Pattern, Digital Technology, Intraoral Scanner, Organisation and Administration, Real World Data on Dentistry, Surveys and Questionnaires

Purpose: To update data on the transfer accuracy of digital implant impressions by using a coordinate-based analysis, latest intraoral scanners (IOSs) were investigated in an established clinical close model set-up. Materials and Methods: An implant master model (IMM) of the maxilla with four implants in the posterior area (#14/#24 and #16/#26) and a reference cube was scanned with four different IOS (i700 (Medit), Primescan (Dentsply Sirona), Trios 4 and Trios 5 (3Shape) ten times each. Datasets were compared with a reference dataset of IMM that was generated with x-ray computed tomography in advance. 3D deviations for the implant-abutment-interface points (IAIPs) were calculated. Statistical analysis was performed by multifactorial ANOVA (p < .05). Results: Overall deviations for trueness (mean) ± precision (SD) of the IAIPs ranged from 88±47 μm for the Primescan, followed by 112±57 μm for the i700, 121±42 μm for the Trios 4 and 124±43 μm for the Trios 5 with decreasing accuracy along the scan path. For trueness, one significant difference between the Primescan and the T4 was detected for one implant position. For precision, no significant differences were noticed. Conclusions: Although the latest IOS showed a significant improvement in transfer accuracy, the accumulating deviation along the scan path is not yet resolved. Considering the Trios system, the innovation seems to be limited as no improvement could be detected between Trios 4 and 5.

Insbesondere in der Implantologie eröffnet der intraorale Scan, neben der alleinigen Funktion einer Abformung, die Möglichkeit zur Implementierung neuer Behandlungskonzepte. Bereits in der Beratungs- und Planungsphase können so in Verbindung mit dreidimensionalen Röntgendaten Möglichkeiten, Grenzen und Risiken der Implantatversorgung erläutert und in einem prothetisch-chirurgischen Behandlungskonzept festgelegt werden, welches zu vorhersagbareren Behandlungsergebnissen führt. Jedoch müssen die heute noch bestehenden Limitationen der Ganzkieferversorgungen in Bezug auf die dreidimensionale Übertragung der Implantatposition von der Mundhöhle auf ein Modell beachtet werden, weshalb indikationsabhängig auch kombiniert digital-analoge Versorgungskonzepte in Betracht gezogen werden sollten. Durch die kontinuierliche Weiterentwicklung der Scansysteme ist jedoch zukünftig damit zu rechnen, dass auch hier die digitale Abformung die etablierten analogen Behandlungsverfahren ersetzen wird. Manuskripteingang: 18.06.2021, Annahme: 11.08.2021 Keywords: digitale Abformung, Implantatabformung, konventionelle Abformung, intraorale Scanner, Abformgenauigkeit, digitale Implantatplanung

Aim: Dental research involves variations between actual and reference datasets of master models to determine the metric accuracy through transfer accuracy tests. Various methods of measurement are used to analyze the results, which are often subjected to direct comparisons. Hence, the aim of the present study was to analyze the influence and effect on results of different methods of digital data analysis, being coordinate-based analysis (CBA) and best-fit superimposition analysis. Materials and methods: A model with four implants and a reference cuboid was digitized through computed tomography (CT), which served as the master model. Ten implant impressions were made using a Trios (3Shape) intraoral scanner, and three different scan bodies (nt-trading, Kulzer, and Medentika) were used. The deviations between the master model and the digital impressions were analyzed using CBA and best-fit superimposition analysis. Statistical analysis was performed using SPSS 25. Results: The deviations in the CBA and best-fit superimposition analysis ranged from 0.088 ± 0.012 mm (mean ± SE; Medentika, 14) to 0.199 ± 0.021 mm (Kulzer, 26), and from 0.042 ± 0.010 mm (Medentika, 16) to 0.074 ± 0.006 mm (Kulzer, 16), respectively. Significant differences were observed between the implant positions in the CBA and the digital measurements at each implant position, whereas the best-fit analysis showed no significant difference between the scan bodies and implant positions. Conclusion: CBA displays an advantage over best-fit superimposition analysis in the detection of possible influencing factors for primarily scientific purposes. However, a global analysis and visualization of angles and torsions is difficult, for which a best-fit evaluation is needed. However, a best-fit analysis better represents the clinical try-in. It is associated with the risk that possible disturbing factors and resulting errors might be leveled out and their identification camouflaged. Keywords: dimensional measurement accuracy, accuracy, trueness, precision, intraoral scanner, digital dentistry, implant impression, best-fit analysis

Heutzutage gibt es die Möglichkeit, Zahnersatz auf der Grundlage einer konventionellen oder einer digitalen Abformung herzustellen. Auch ein kombinierter Einsatz beider Techniken ist durch das laborseitige Einscannen eines Gipsmodells realisierbar. In Bezug auf die Genauigkeit führt die digitale Abformung insbesondere bei kleineren Restaurationen zu ähnlichen Ergebnissen wie die konventionelle Abformung. Hingegen ist bei der Ganzkieferabformung zu beachten, dass die Exaktheit zwar zur Anfertigung von Hilfsmitteln wie Modellen, Schienen oder Bohrschablonen ausreicht, jedoch langspannige Implantatversorgungen heute besser noch mittels herkömmlicher Techniken abgeformt werden sollten. Neben der alleinigen Abformung bieten einige Hersteller bereits weitere Funktionen wie digitales Monitoring oder Kariesdiagnostik an. In diesem Bereich ist zukünftig sicher noch mehr zu erwarten, so dass die digitale Abformung im Vergleich zur konventionellen einen zusätzlichen Informationsgewinn bringt. Keywords: Digitale Abformung, optische Abformung, konventionelle Abformung, intraorale Scanner, Abformgenauigkeit

Objectives: The aim of this retrospective pilot study was to analyze the clinical performance of computer-engineered complete dentures (CECDs) in edentulous patients regarding survival and maintenance. Method and materials: For this retrospective analysis, data from 10 patients who received CECD treatment in each arch (Digital Denture, Ivoclar Vivadent) between 2015 and 2016 were analyzed. The following aspects were assessed: number of appointments required for treatment, number of interventions during the initial (≤ 4 weeks after insertion) and functional periods (> 4 weeks after insertion), and survival. Additionally, whether these aspects were influenced by function or esthetics, the arch, or recall participation was assessed. Poisson regression models were used for the statistical analysis (P .05). Results: All CECDs survived the observation period of 2.54 ± 0.48 years. More than four appointments were required for treatment (mean ± standard deviation, 4.6 ± 0.7), mainly for esthetic concerns. An average of 1.7 ± 0.05 appointments during the initial period and 2.07 ± 0.32 during the functional period were noted as a consequence of functional concerns. During both periods, the major reason for intervention was removal of pressure spots. Relining was required in 40% of the CECDs, and fracture of the denture base occurred in two CECDs. Conclusions: Within the limitations of this retrospective pilot study, the CECDs showed acceptable clinical performance in terms of survival and maintenance. Nevertheless, transferring more information about the patient from the dental practice to the dental laboratory might reduce the number of appointments for treatment and avoid technical complications such as fractures of the denture base. Keywords: CAD/CAM complete denture, computer-engineered complete dentures, maintenance, survival

Purpose: To investigate whether (1) the curing mode and (2) the use of the corresponding or noncorresponding crown luting system have an impact on the microleakage of computer-aided design/ computer-assisted manufacture (CAD/CAM) composite crowns after chewing simulation. Materials and Methods: Two CAD/CAM composite blocks (Lava Ultimate [n = 20] and LuxaCam Composite [n = 20]) and their luting systems and curing modes (light curing [LC] or chemical curing [CC]) were investigated. A dye penetration test was used to detect the presence of microleakage. Results: Independently of the luting system, the LC groups showed a significantly lower microleakage compared to the CC groups (P .05). Furthermore, the CC groups exhibited a reduction of microleakage if the CAD/CAM block and luting system were from the same manufacturer. Conclusion: For the CC mode, the corresponding block and luting system should be used.

Aim: For orthodontic aligner treatment, excellent full-arch impressions with correctly displayed interdental areas (IAs) are required. To analyze the ability of impression taking of the IAs in periodontally compromised dentitions, two intraoral scanning systems and one conventional impression technique were investigated in vitro under standardized testing conditions. Materials and methods: A total of 60 impressions of the maxilla and mandible were taken from a periodontally compromised test model (A-PB) with three different techniques (n = 20): One conventional impression (EXA'lence) (CVI) and two digital impressions with the intraoral scanners Trios III (3Shape) (TIO) and True Definition (3M ESPE) (TRU). Standard tessellation language (STL) datasets were generated for TIO and TRU, whereas type IV dental stone casts were manufactured for CVI. The casts were then digitized with a laboratory scanner (ATOS). The percentage of displayed IAs in relation to the complete IA was calculated for each IA using evaluation software (GOM Inspect). Finally, the data were subjected to the median test. Result: TRU showed a significantly higher percentage of displayed IAs compared with the other two methods (P 0.05). Only a few IAs were shown in CVI. TIO showed significantly better results compared with CVI, although the results were not as good as those of TRU. Conclusion: Within the limitations of this in vitro study, intraoral scanners - and especially the one based on active wavefront sampling (AWS) technology (as for TRU) - can be recommended for the reproduction of wide IAs (undercuts) in periodontally compromised patients. Keywords: intraoral scanners, periodontally compromised dentition, full-arch impression, aligner treatment, orthodontics, digital dentistry