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This study investigated the effects of different surface treatments and a silane-containing adhesive on the repair bond strength between fresh and aged resin composites. A total of 140 composite specimens were prepared and aged for 24 h or 4 months. Each group was subdivided into seven subgroups (n = 10) depending on the surface treatment (no surface treatment (NT), sandblasting (SAND), or Sof-lex coarse disc (DISC)) in combination with the use of the silane-containing adhesive ScotchBond Universal Plus (SBU) or an adhesive without silane Prime&Bond Universal (P&B). The same composite was used for the repair as for the primary specimen. Specimens were dark stored in distilled water at 37 °C for 28 days. Shear bond strength was tested at a crosshead speed of 0.5 mm/min. The Kruskal–Wallis test with Bonferroni's post-hoc adjustment (α = 0.05) and the Mann–Whitney U-test were used for the statistical analysis. The results are shown as the median with the interquartile range. The highest bond strength (MPa) was achieved after 24 h in the DISC+P&B (20.39(16.85–28.83)). In the fresh 24 h group, the SAND+P&B (12.25(8.28–15.05)) and DISC+SBU (18.37(15.16–21.29)) were statistically similar. In the 4-month groups, both adhesives and surface treatments performed similarly. The NT, SAND, and DISC groups without adhesives had the lowest bond strength. In the repair of fresh or aged composite, the silane-containing adhesive SBU was not superior to the adhesive without the silane (P&B). [ABSTRACT FROM AUTHOR]

Introduction: The education of Oral Health Professionals (OHPs) is variable across Europe and consequently, there is concern that research skills are not consistently or optimally integrated into European OHP curricula. The aim of this study is to investigate the perspectives of European OHP students regarding the inclusion of research in the undergraduate curriculum. Materials and Methods: A 21‐question online survey was administered to dental, dental hygiene, and dental hygiene and therapy students across Europe. Informed consent was obtained from participants and all responses remained confidential. Quantitative and qualitative methods were used to analyse the data. Results: A total of 825 student responses to the survey from 33 European countries were eligible for inclusion. The results demonstrated that OHP students recognise the importance of research in the dental field and value the inclusion of research in the curriculum. Although students indicated that they are interested to learn more about research, the survey results also showed that students had neutral opinions towards the existing curriculum providing enough training about research. Conclusion: European OHP students agree on the need for an open and explicit research curriculum in OHP education. The development of a research domain within an open curriculum framework would help to harmonise the teaching and assessment of OHP research skills across Europe and ultimately improve graduating OHP's research skills. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether Fourier transform infrared spectroscopy (FTIR) can be used to identify the point at which polymerization begins when dental restorative composites are exposed to ambient light. Materials and methods: An FTIR spectrometer with an attenuated total reflectance (ATR) diamond accessory and a mercury-cadmium-telluride detector was used to evaluate real-time changes in the degree of conversion (DC) at a fast data collection rate (2 spectra/s). The 0.1 and 0.2 mm thick samples of three commercial composites (OmniChroma, Tetric PowerFill, and Filtek One Bulk Fill) were irradiated with white light simulating dental operating light (temperature of 4,000 K and illuminance of 8,000 lux, according to the recommendations of ISO 4049). The DC data were plotted as a function of time and the first derivative was calculated. The first time point with a non-zero value of the first derivative was considered to indicate the start of the polymerization reaction. Results: Statistically significant differences in time of onset of polymerization were observed between the materials at both layer thicknesses (p<0.001) with the following material ranking: OmniChroma > Tetric PowerFill > Filtek One Bulk Fill. The highest mean values were measured for OmniChroma (161.75 s / 193.0 s) while the lowest mean values were observed for Filtek One Bulk Fill (76.0 s / 96.75 s) for 0.1 mm and 0.2 mm thick layers, respectively. Statistically significant effects of layer thickness were observed for OmniChroma (p=0.002) and Filtek One Bulk Fill (p<0.001), while Tetric PowerFill showed no significant effect of layer thickness (p=0.350). Conclusions: High-speed ATR-FTIR spectrometry can be used to detect early signs of the onset of polymerization of dental restorative composites with high sensitivity and reproducibility. [ABSTRACT FROM AUTHOR]