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The objective of this study was to evaluate the fracture load and retention force of different bonding systems while restoring one-piece zirconia implants with a novel cementation approach using a mesostructure. Polymer-infiltrated ceramic mesostructures (n = 112) were therefore designed as caps on the implant abutment, and a molar feldspathic ceramic crown was constructed on top of it as a suprastructure. For cementation, different bonding systems were used. Fracture load and retention force were measured immediately after storage in water at 37 °C for 24 h (n = 8) as well as after artificial aging in a chewing simulator and subsequent thermal cycling (n = 8). Combined restorations showed higher fracture load compared to monolithic restorations of polymer-infiltrated ceramic (n = 8) or feldspathic ceramic (n = 8) identical in shape. However, the fracture load of the combined restorations was significantly affected by aging, independent of the primers and cements used. Restorations cemented with primers containing methyl methacrylate and 10-methacryloyloxydecyl dihydrogen phosphate exhibited the highest retention force values. Aging did not affect the retention force significantly. Similar fracture load values can be expected from combination restorations when compared with monolithic crowns.

Objective This study evaluated the loading capacity of CAD/CAM‐fabricated anterior feldspathic ceramic crowns bonded to one‐piece zirconia implants with different cements. Material and methods Fifty one‐piece zirconia implants were embedded in epoxy resin. The abutment aspect of one implant was optically scanned and a standardized upper canine was designed with CAD‐software. Fifty feldspathic ceramic crowns were milled, polished, and mounted on the implants either without any cement, with a temporary cement or with three different composite resin cements after surface pretreatment as recommended by the manufacturers (n = 10). After storage in distilled water at 37°C for 24 hr, specimens were loaded until fracture on the palatal surface of the crown at an angle of 45° to the long axis of the implant and loads until fracture were detected and compared. Compressive strength of the investigated cement materials was determined. Statistical analyses were done with One‐way ANOVA followed by post hoc Fisher LSD test (α = 0.05). Results The cements revealed significantly different compressive strength values (temporary cement: 37.1 ± 7.0 MPa; composite resin cements: 185.8 ± 21.3, 277.9 ± 22.1, and 389.0 ± 13.6 MPa, respectively). Load‐at‐fracture values had an overall mean value of 237.1 ± 58.2 N with no significant difference among the composite resin cements (p > 0.05). Fracture load values with the temporary cement or without cement were significantly lower (p < 0.002). Conclusions CAD/CAM‐fabricated anterior feldspathic ceramic crowns bonded to one‐piece zirconia implants provide sufficient resistance to intraoral forces.

ObjectivesIsolation precautions (IP) are applied to prevent transmission of pathogens in healthcare settings. Potential negative health outcomes experienced by patients have been previously described but results remain conflicting. We aimed at evaluating the psychological impact of IP in adult patients in isolation using a novel psychological assessment tool.Study designProspective matched cohort study.SettingTertiary care centre in Switzerland.ParticipantsHospitalised patients under IP and non-isolated patients were matched by ward, age and illness severity.Outcome measuresWe measured surrogates of mental and social well-being by using the Pictorial Representation of Illness and Self Measure (PRISM) instrument once during hospitalisation. PRISM is a visual psychometric instrument that has been validated as a quantitative measure of suffering. Smaller distance in self-to-illness separation (SIS) signifies higher importance for a patient.Results156 patients agreed to participate of which 63 were under IP and 93 were matched controls. Median (IQR) duration of isolation was 5 days (2–10). The median SIS (IQR) for perceived inferior nurses’ care was 22.8 (18.5–24.3) and 23.8 (23.3–25.5) for isolated and non-isolated patients, respectively (p<0.001). Similarly, median SIS (IQR) was significantly smaller in isolated than non-isolated patients for avoidance by visitors with 17.5 (7.7–22.0) and 22.2 (21.8–22.6), for loneliness with 7.5 (3.6–16.0) and 18 (10.2–21.6) and for feeling impure with 19 (17.0–21.5) and 21.5 (18.9–22.1), respectively (all p values<0.05).ConclusionsIP to prevent transmission of pathogens may negatively impact mental and social well-being. Measures to alleviate adverse effects of IP should be taken routinely.