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This document is a scientific study that examines the contamination levels on dental abutments and the effectiveness of a cleaning protocol. The study finds that custom-made abutments have surface pollutants, and laboratory procedures increase the amount of pollutants. However, the cleaning protocol tested is highly effective in cleaning both titanium and zirconia abutments. The study suggests that decontaminating abutments before placement may improve tissue integration. [Extracted from the article]

In this paper, gold nanorods' (GNRs) interaction with different proteins (i.e. carbonic anhydrase, lysozyme, ovalbumin and bovine serum albumin (BSA)) at physiological pH is investigated using localized surface plasmon resonance (LSPR) spectroscopy. We observe that the incubation of these proteins at different concentrations with cetyltrimethylammonium bromide-capped GNRs of three aspect ratios induces dramatic changes in the extinction spectra of the nanoparticles. In particular, we correlate the position and shape of the longitudinal LSPR peaks to the ability of the proteins to specifically interact with GNRs' surface. The different types of behaviour observed are explained by the exposed molecular surface area of the proteins' cysteine residues as modelled on the basis of their respective X-ray crystallographic data structures. Cysteine is the only amino acid that exhibits an SH group that is well known to have a strong affinity to gold. The presence and the accessibility of such a residue may explain the protein binding to GNRs. The isoelectric point of the proteins is also an important characteristic to take into account, as the electrostatic strength between GNRs and protein explains some of the cases where aggregates are formed. Keywords Proteins. LSPR. Gold nanorods (GNRs). isoelectric point. Solvant accessible area, Introduction During the last decades when nanosciences have made their revolution, gold nanoparticles (GNPs) have attracted particular interests for many reasons. Among them, two have drawn our attention in the [...]

Aim: The aim of this in vitro study was to investigate the influence of scan paths on the accuracy (trueness and precision) of intra-oral scanning of an implant impression on an edentulous patient., Material and Methods: An epoxy resin maxillary model was made with 6 bone level implants (NobelParallel Conical Connection RP, NobelBiocare®). The implants were placed at the spot of the first incisor, the canine and the first molar. The trans gingival component (Multi-unit, NobelBiocare®) was screwed onto the implants. The scanbodies (IO 2C-A, Elos Accurate®) were then screwed onto the multi-units. The model was run through a coordinate measurement machine to obtain a control cast. Then, five different scanning paths, respectively the zigzag technique (ZZT), the zigzag technique with palatal (ZZTP), the wrap technique (WT), the wrap technique with palatal (WTP), and the big zigzag technique (BZZT), were applied by a single operator. Finally, each scan was compared to the control model. Results were assessed by one-way ANOVA and linear mixed effects models at P<0.05., Results: The study showed that scan paths ZZT and ZZTP had significantly lower absolute positioning errors and residual mean square errors than the others (P<0.0001). For distances between consecutive implant axes and for absolute vertical errors, their superiority was borderline (P<0.10). Overall, techniques ZZT and ZZTP were equally performant and proved to be the most accurate., Conclusions: This in vitro experimental study demonstrates that the scan path can have an influence on the accuracy of the optical impression for full arch rehabilitation on implants.