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Purpose: To compare the performance of licensed dentists and two software versions (3.5 legacy and 4.0) of an artificial intelligence (AI)-based chatbot (ChatGPT) answering the exam for the 2022 Certification in Implant Dentistry of the European Association for Osseointegration (EAO). Materials and Methods: The 50 question, multiple-choice exam of the EAO for the 2022 Certification in Implant Dentistry was obtained. Three groups were created based on the individual or program answering the exam: licensed dentists (D group) and two software versions of an artificial intelligence (AI)-based chatbot (ChatGPT)—3.5 legacy (ChatGPT-3.5 group) and the 4.0 version (ChatGPT-4.0 group). The EAO provided the results of the 2022 examinees (D group). For the ChatGPT groups, the 50 multiple-choice questions were introduced into both ChatGBT versions, and the answers were recorded. Pearson correlation matrix was used to analyze the linear relationship among the subgroups. The inter- and intraoperator reliability was calculated using Cronbach’s alpha coefficient. One-way ANOVA and Tukey post-hoc tests were used to examine the data (α = .05). Results: ChatGPT was able to pass the exam for the 2022 Certification in Implant Dentistry of the EAO. Additionally, the software version of ChatGPT impacted the score obtained. The 4.0 version was able to not only pass the exam but also obtained a significantly higher score than the 3.5 version and licensed dentists completing the same exam. Conclusions: The AI-based chatbot tested was able to not only pass the exam but performed better than licensed dentists.

Purpose: to measure the surface temperature distribution after CO2-laser heating of titanium dental implants using different power settings, application intervals and irradiation times. Materials and methods: 10 tissue-level-type titanium implants (Camlog Screw-line Promote Plus 4.3mm x 11mm) were embedded (Epofix, Struers ApS, Copenhagen, Denmark) and irradiated with a carbon-dioxide-laser (Denta II, Lutronic Corporation, Fremont, USA) with a wavelength of 10.6µm and at power levels of 4watts (group 1), 6watts (group 2), 8watts (group 3) and 10watts (group 4). A continuous beam mode (setting I) and non-continuous beam modes with 5second (setting II) and 10second (setting III) pause intervals were used. For each setting, a total irradiation time of 50seconds was used and repeated 10 times. The temperature was measured using external thermocouples (Testo SE & Co. KGaA, Lenzkirch, Germany) in contact with the implant surface at implant shoulder, middle and apex. A linear regression model was used to analyse the data (p = 0.05). Results:  Setting I demonstrated the most rapid increase in implant surface temperature in all three test sites as well as the greatest total temperature at 50 seconds of irradiation time. The greater the pause interval (settings II and III) during the 50 seconds of irradiation, the lower the rate of temperature increase as well as the total temperature in all three test sites and with all power levels. The average temperature difference between the apex and shoulder site was significant for test setting III for all groups, but not for any groups in settings I and II. Conclusion: Heating the internal aspect of a dental implant with a CO2-laser produces different temperature distribution profiles depending on the laser power level and the application interval. Laser-beam irradiation leads to a temperature gradient which is greatest at the implant apex and smallest at the implant shoulder. 

Purpose: To evaluate the accuracy of complete-arch digital implant impressions using different intraoral scan body (ISB) materials and intraoral scanners (IOSs). Materials and Methods: The mandibular dental cast of an edentulous patient with six tissue-level dental implants was used as master cast. Two types of ISBs, polyether-ether-ketone (PEEK) and plasma-coated medical titanium, were used with five IOSs: TRIOS 4 (T4), Virtuo Vivo (VV), Medit i700 (Mi700), iTero5D (i5D), and Primescan (PS). To assess accuracy, digital impressions (n=10) with each IOS and ISB were compared to two reference models obtained by digitizing the master cast with each ISB type using a desktop scanner (IScan4D LS3i) and importing the scan data into metrology software (Geomagic Control X). Root-mean-square (RMS) error was employed to evaluate overall deviation values (trueness), while precision was determined using the standard deviation (SD) of RMS values. Statistical significance was set at P < 0.05. The Kruskal-Wallis test was used, followed by the pairwise comparison method with Bonferroni correction (α=.05). Results: An interaction between ISB material and IOS was found (P=0.001). Plasma-coated medical titanium ISBs demonstrated significantly higher trueness and precision compared to PEEK ISBs with T4 (P=0.001), Mi700 (P=0.001; P=0.004), and i5D (P=0.001). Conversely, VV exhibited higher trueness and precision values with PEEK ISBs (P=0.005; P=0.003). PS provided the highest trueness and precision regardless of the ISB material (P=0.912). T4 showed the lowest accuracy for PEEK ISBs, and VV for plasma-coated medical titanium ISBs. Conclusion: Except for PS, all IOSs showed significant differences between ISB materials. PS demonstrated the highest accuracy with both ISB materials, whereas T4 had the lowest accuracy for PEEK ISBs, and VV showed the lowest accuracy for plasma-coated medical titanium ISBs.

Purpose: To evaluate the wear resistance of a printed interim resin manufactured with different printing and postpolymerization parameters. Materials and Methods: Overall, 130 rectangular resin specimens (15 × 10 × 10 mm) were 3D-printed. Among the specimens, 60 were printed with different printing orientations (0, 45, and 90 degrees) and layer thicknesses (50 and 100 μm) to create six groups to investigate the effects of the printing parameters (n = 10 per group). The remaining 70 specimens were used to evaluate the effects of postpolymerization; for this, seven groups were created as follows (n = 10 per group): nonpostpolymerized; postpolymerized for 5, 15, and 30 minutes with an ultraviolet light–emitting diode (LED) device; and postpolymerized for 5, 15, and 30 minutes with an ultraviolet light bulb device. After masticatory simulation, the wear volume loss was calculated with 3D metrology software. One-way and two-way ANOVA were used for intergroup comparisons (α = .05). Results: The group printed with a build angle of 45 degrees showed lower wear volume loss than the 0- and 90-degree groups (P < .01). The wear volume loss in the ultraviolet LED group was significantly greater than that in the ultraviolet light bulb group (P = .04). No significant difference was observed in the wear volume loss of the printed resin with respect to the layer thickness and polymerization time (P > .05). However, the non-postpolymerized group showed significantly greater wear volume loss than the other groups (P < .001). Conclusions: The printed resin showed greater wear resistance when it was printed at a build angle of 45 degrees and postpolymerized with an ultraviolet light bulb device.

Ziel: In dieser retrospektiven Studie sollte die (technische und biologische) Langzeitbewährung ausgedehnter keramischer Oberkieferfrontzahnveneers mit einer inzisalen Dicke von mehr als 2 mm untersucht werden. Material und Methoden: Patienten, die zwischen 1990 und 2003 an der Universitätszahnklinik Genf von demselben Zahnarzt mit ausgedehnten Keramikveneers versorgt worden waren, wurden zu einer Nachuntersuchung eingeladen. Von den 37 identifizierten Patienten erklärten sich zehn Patienten mit 50 Veneers zu der Nachuntersuchung bereit und wurden inkludiert. Die Überlebensraten sowie die technischen und biologischen Ergebnisse wurden durch eine klinische Untersuchung bestimmt (anhand der modifizierten United States Public Health Services-Kriterien). Zusätzlich wurden die Patientenakten ausgewertet, um die Patientendaten und alle Komplikationsereignisse zu erfassen. Schließlich wurden Patient-R eported Outcomes (PRO) zu den Aspekten Ästhetik, Funktion und Phonetik, Kaufunktion, Zahnempfindlichkeit und Bereitschaft zu einer Ersatzversorgung im Fall eines Restaurationsversagens mithilfe visueller Analogskalen erhoben. Die Daten wurden deskriptiv ausgewertet. Die Analyse des Restaurationsüberlebens und der Komplikationsereignisse erfolgte mittels Kaplan-Meier-Schätzer. Ergebnisse: Die Überlebensrate der Veneers betrug 96 % nach im Mittel 20,7 ± 3,7 Jahren in Funktion. Die Rate technischer Komplikationen lag bei 30 %. Diese Komplikationen bestanden in zwei Veneerverlusten, neun reparablen Frakturen, drei Rissbildungen und einer Veneerverlagerung durch Zahnunfall. Es fanden sich weder über Kreideflecken hinausgehende Kariesläsionen noch endodontische Komplikationen dokumentiert. Die PRO bezüglich Zufriedenheit mit der Ästhetik und der Phonetik waren sehr gut. Schlussfolgerungen: Im Rahmen dieser retrospektiven Studie erwiesen sich ausgedehnte Keramikveneers, gemessen an den klinischen Ergebnissen und der Patientenzufriedenheit, als langfristig erfolgreiche Versorgungsmöglichkeit. Keywords: adhäsive Zahnmedizin, Ästhetik, Keramik, Prothetik, restaurative Zahnmedizin, Veneers

Aim: The aim of the present retrospective study was to evaluate the long-term results, including technical and biologic outcomes, of maxillary extended porcelain veneers with an incisal edge thickness above 2 mm. Materials and methods: Patients treated with extended porcelain veneers performed by a single clinician at University of Geneva between 1990 and 2003 were identified and invited to an examination. Of the 37 identified patients, 10 patients with 50 veneers agreed to be examined and were included. A clinical examination was performed to assess survival rates as well as technical and biologic outcomes (modified United States Public Health Services criteria). Patient records were also reviewed to retrieve patient and reconstruction data and every complication event. Patient-reported outcome measures (PROMs) were evaluated using a visual analog scale to measure esthetic satisfaction, functional and phonetic comfort, masticatory improvement, tooth sensitivity, and acceptance of restoration replacement in case of failure. Data were descriptively analyzed, and Kaplan-Meier survival estimators were computed for survival rates and complication events. Results: The survival rate of the veneers was 96% after a mean follow-up of 20.7 ± 3.7 years in function. The technical complication rate amounted to 30%, including two failures, nine repairable fractures, three cracks, and one displacement due to trauma. No cavitated caries lesions or endodontic complications were registered. PROMs were very high for esthetic satisfaction and phonetic comfort. Conclusions: Within the limitations of the present retrospective study, extended porcelain veneers appear to be a successful long-term treatment option in terms of clinical outcomes and patient satisfaction. Keywords: adhesive dentistry, esthetics, ceramics, prosthodontics, restorative dentistry, veneers

Purpose: To investigate the influence of a novel scanning strategy—using two new intraoral scanner devices with different operators—on the full-arch scanning accuracy for a dentate maxilla. Materials and Methods: Two scanning strategies, a test and a control strategy, were used to produce full-arch impressions of the dentate maxilla of a study patient. Two intraoral scanning (IOS) devices were used. Five expert operators performed a total of 40 scans. The scan time was recorded for each. A reference model was obtained from the patient’s maxillary arch with an analog impression. The model was later scanned with a high-precision laboratory scanner to create a digital reference model (DRM). The scanning accuracy was analyzed with 3D-analysis software using a root mean square (RMS) calculation method, and qualitative analysis was executed using machine learning software. Results: The mean RMS result for the test strategy was 82.8 ± 16 μm compared to 81.5 ± 16 μm for the control strategy. The mean RMS results were 84.7 ± 15 μm for Primescan (PS) and 79.6 ± 17 μm for 3Shape (3S). As such, the scanning strategies and IOS devices did not influence the scanning accuracy. Yet, a significant difference was found when the two strategies’ scanning times were compared (P = .001), as well as the IOS devices (P = .001). The operator was found to have no influence on the scanning strategy. Conclusions: The accuracy of digital impressions is not influenced by different strategies, devices, or operators, in contrast with the scanning time, which is influenced by both strategies and devices.