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The Covid‐19 pandemic has forced all dentistry faculties to quickly shift to the online supplementation or replacement of traditional modules to pursue education. However, there is limited research evaluating the effectiveness of this education modality on student performance in dental anatomy and manipulation module. Accordingly, it was aimed to compare the influence of different education modalities on the performances of the students enrolled in this module. The students were requested to perform 11 practical assignments throughout the fall term. A total of 220 face‐to‐face‐educated (F2F) and 138 screen‐to‐screen‐educated (S2S) students were included. To evaluate the influence of education modality on the performances of the students, cumulative success scores were calculated and compared using an independent t‐test. The grades of the first (maxillary central), sixth (maxillary premolar), and eleventh assignments (mandibular first molar) were also analyzed to understand the manipulation‐skill progress of each student within the same year. The grades of above‐mentioned three assignments were converted into nominal data (excellent, very good, good, acceptable, and fail) based on certain thresholds, and a chi‐square test was conducted. The cumulative success scores in F2F group were significantly lower than those in S2S group ( P = 0.02). Differences between the first and eleventh tasks in both education modalities were significant ( P < 0.05). The S2S‐educated students achieved significantly higher achievement points in the sixth and eleventh assignments ( P < 0.001). The S2S education can be suggested as an applicable modality for teaching dental anatomy and manipulation module. However, further work is needed to ascertain whether this result is replicable throughout dental anatomy education.

During the COVID-19 pandemic, the necessity of social isolation led education to be distance-and online instead of face-toface (F2F). Education strategies became more challenging for the educationalists at dentistry faculties, since dental education is based on mostly practical tutorials. All over the world, the faculties tried to develop policies to protect the health of students and academic staff, as well as to ensure the continuity and quality of education. In our faculty (Near East University Faculty of Dentistry), online education was held for the spring semester with the aid of distance learning and the information technology centre of the university. In this study, it was aimed to examine the background of the virus, the proactive measures in the dental setting to combat COVID-19 outburst, and information technology-based educational measures adopted in Cyprus to ensure the continuation of dental education. The strategies used for online education in our faculty, the difficulties that were encountered, and future recommendations for e-learning were declared. Moreover, students' perception and satisfaction regarding online education model both for theoretical (120 students, response rate 78%) and practical lectures (220 students, response rate 82%) were investigated. With this regard, students were asked to answer reflective questions. Descriptive data were presented. A considerable number of the students stated that practical implementations should have been conducted F2F. Most of the students emphasised that online theoretical courses are more advantageous than F2F ones.

Objective: To investigate the influence of surface treatments conducted in presintering and postsintering stages on flexural strength and optical properties of zirconia.Materials and methods: Specimens were milled from partially sintered zirconia blocks in different geometries and divided into three main groups as presintered, postsintered, and control groups. Test groups were further divided into three subgroups (n = 10) according to the surface treatments conducted (grinding, Er,Cr:YSGG laser irradiation, air-borne particle abrasion [APA]). Four-point flexural strength (σ) test and Weibull analysis were conducted. Color differences (ΔE 00 ) and translucency parameter (TP ab ) were calculated with a spectrophotometer. Surfaces of specimens were scrutinized under FESEM. Data were statistically analyzed.Results: Postsintered groups exhibited higher σ values (P < .05). Within all groups, highest and lowest σ values were detected at postsintered and presintered APA groups, respectively (P < .05). All ΔE 00 values were above the perceptibility threshold (ΔE 00 > 0.8). Higher TP ab values were obtained and deeper scratches were observed in presintered groups.Conclusions: Surface treatments performed at postsintering stage had a favorable effect on the flexural strength of all specimens. Surface treatments performed before sintering increased translucency and caused higher ΔE 00 values.Clinical significance: Surface treatments performed at different sintering stages can alter mechanical and optical properties of zirconia.

PURPOSE This study aimed to assess the influence of various micromechanical surface conditioning (MSC) strategies with or without coupling agent (silane) application on the micro-shear bond strength (µSBS) of resin- matrix ceramics (RMCs). MATERIALS AND METHODS GC Cerasmart (GC), Lava Ultimate (LU), Vita Enamic (VE), Voco Grandio (VG), and Brilliant Crios (BC) were cut into 1.0-mm-thick slices (n = 32 per RMC) and separated into four groups according to the MSC strategy applied: control-no conditioning (C), air-borne particle abrasion with aluminum oxide particles (APA), 2W- and 3W-Er,Cr:YSGG group coding is missing. The specimens in each group were further separated into silane-applied and silane-free subgroups. Each specimen received two resin cement microtubules (n = 8 per subgroup). A shear force was applied to the adhesive interface through a universal test machine and µSBS values were measured. Data were statistically analyzed by using 3-way ANOVA and Tukey HSD test. Failure patterns were scrutinized under stereomicroscope. RESULTS RMC material type, MSC strategy, and silanization influenced the µSBS values ( P <.05). In comparison to the control group, µSBS values increased after all other MSC strategies ( P <.05) while the differences among these strategies were insignificant ( P >.05). For control and APA, there were insignificant differences between RMCs ( P >.05). The silanization decreased µSBS values of RMCs except for VE. Considerable declines were observed in GC and BC ( P <.05). CONCLUSION MSC strategies can enhance bond strength values at the RMC - cement interface. However, the choice of MSC strategy is dependent on RMC material type and each RMC can require a dedicated way of conditioning.