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This study compared the structural integrity and fracture mode of teeth restored with traditionally and minimally prepared resin-bonded CAD/CAM inlays fabricated from the same material.Forty intact maxillary premolars were used and divided into four groups. Two groups were prepared according to a traditional inlay preparation design (2.0 mm occlusal reduction, a 1.5 mm wide proximal box and divergent walls) and two groups were prepared according to a newly proposed minimal preparation design (round shaped cavity with 1.0 mm occlusal reduction, a U-shaped proximal box 1.0 mm wide and parallel walls). Two restorative systems were tested: a composite system comprised of Paradigm MZ100 (3M ESPE) blocks and RelyX Unicem (3M ESPE) resin cement and a ceramic system comprised of ProCAD blocks (Ivoclar-Vivadent) and Variolink II (Ivoclar-Vivadent) resin cement. The inlays were cemented according to the manufacturers' instructions. Each specimen was loaded axially to its occlusal surface at a crosshead speed of 0.5 mm/minute in a universal testing machine until fracture. The fracture load data were analyzed using ANOVA, comparing inlays of the same restorative material. Also, the mode of fracture of the inlays was recorded and analyzed using a non-parametric test (Kruskal-Wallis).In the composite system case, the mean fracture load and SD were 1322 N (+/- 445) for the traditional inlays and 1511 N (+/- 395) for the minimal inlays, while in the ceramic system case, those values were 1135N (+/- 450) for the traditional inlays and 1761 N (+/- 494) for the minimal inlays. Statistical analysis of the results showed that there was no statistically significant difference between the two designs for the composite system, while for the ceramic system, the minimally prepared teeth showed higher mean fracture strength. Non-parametric analysis (Kruskal-Wallis) of the mode of fracture showed that there was no statistically significant difference between traditionally and minimally prepared inlays for both systems (p.05).Under the conditions of this experimental study, only the ceramic inlays, when prepared with a minimal preparation design, demonstrated a higher fracture strength as compared to the traditionally prepared teeth. Use of the proposed minimal preparation design did not compromise the immediate post-operative structural integrity of teeth restored either with resin composite or ceramic inlays.

The purpose of this study was to present and evaluate a blended-learning course developed for undergraduate (B.D.S.), postgraduate, and diploma (hygiene and therapy) students at the University of Sheffield School of Clinical Dentistry. Blended learning is the integration of classroom face-to-face learning with online learning. The overall methodology used for this study was action research. The data were collected using three processes: questionnaires to collect contextual data from the students taking the course; a student-led, nominal group technique to collect group data from the participants; and a non-participant observer technique to record the context in which certain group and individual behaviors occurred. The online component of the course was accepted as a valuable resource by 65 percent of those responding. While online information-sharing occurred (31 percent of the students posted in forums), there was no evidence of online collaboration, with only 8 percent replying to forum postings. Accessibility of the online environment was one of the main concerns of the students at the nominal group sessions. Differences regarding overall engagement with the course between the student groups (years) were observed during the sessions. The majority of the students were satisfied with the Information and Communication Technologies (ICT) course. No statistically significant differences between males and females were found, but there were differences between different student cohorts (year groups).