Is galvanic corrosion between implant abutments and roots a possible scenario? An experimental study under simulated healthy and inflammatory peri-implant conditions and F anions.

Purpose: To assess the effect of healthy and inflammatory conditions and the presence of F anions on the galvanic coupling between the root surface and titanium abutments of commercially available titanium implants MATERIALS AND METHODS: Eight pairs of three dental root-abutment couples (BEGO, MIS, NOBEL) were exposed to a neutral (pH=7.4) (HE) and an acidic (pH=4.0) (IN) phosphate buffer solution (PBS) simulating healthy and inflammatory conditions respectively.

Microplastics and orthodontic aligners: The concerns arising from the modernization of practice through polymers and plastics.

Plastic aligners have transformed orthodontics, offering a discreet, comfortable, and aesthetically pleasing alternative to traditional fixed appliances. While they have advantages over fixed appliances, they come with environmental and health concerns due to the use of nonbiodegradable plastics, such as the leaching of Bisphenol-A (BPA) and microplastics that can impact human health directly through ingestion. Studies have shown that plastic aligners release microplastics during use, raising concerns about their potential health effects and environmental pollution.

Effect of Photoaging on the Structure, Optical Properties and Roughness of One-Shade Composite Restoratives.

The aim of the study was to evaluate changes in the degree of C=C conversion (DC%), chemical structure, optical properties and roughness of one-shade composites before/after photoaging. Τhe one-shade materials tested were Charisma Topaz One (CHT), Clearfil Majesty ES-2 Universal (MES), Essentia Universal (ESU) and Omnichroma (OMN), with G-aenial Anterior (CNA) serving as control. Specimens (2 mm thickness) were prepared and tested for DC% and chemical structure (ATR-FTIR spectroscopy), optical properties (L*a*b*-ΔΕ, translucency parameter-TP, opalescence parameter-OP, contrast ratio-CR and total transmittance-TT by UV-Vis spectroscopy) and roughness (Sa, Sz, Sdr, Sds and Sc by optical profilometry) before and after photoaging (Xe-arc weatherometer).

Intraoral ageing of aligners and attachments: Adverse effects on clinical efficiency and release of biologically-active compounds.

The clinical application of aligners is accompanied by the ageing of the polymer appliances and the attachments used, which may result in inefficiency in reaching the predicted range of tooth movement, and release of compounds and microplastics in the oral cavity as a result of the friction, wear and attrition of the aligner and composite attachment. The purpose of this review is to present the mechanism and effects of ageing; describe the hydrolytic degradation of aligners and enzymatic degradation of composite attachments; examine the ageing pattern of aligners , under actual clinical scenarios; and identify a link to the discrepancy between predicted and actual clinical outcome. Lastly, strategies to deal with three potentially critical issues associated with the use of aligners, namely the necessity of weekly renewal, the dissimilar mechanical properties of aligner and attachment resulting in wear and plastic deformation of the aligner, and the development of integuments and biofilms with microbial colonization of the appliance, are discussed.

Degree of conversion of dual-cured composite luting agents: The effect of transition metal-based touch-cure activators.

Purpose: The aim of the study was (a) to assess the effect of universal adhesives and tooth primers with novel touch-cure activators on the conversion of dual-cured resin composite luting agents (RLAs) polymerized under the self-curing mode, and (b) to investigate the source of the catalytic effect exerted by the activators.

Materials And Methods: The materials selected were the adhesive RLAs Panavia V5/Tooth Primer (PV5/TP5), Variolink Esthetic DC/Adhese Universal DC (VLE/ADC), and the self-adhesive RLAs GCem ONE/AE Primer (GCO/AEP), RelyX Universal/Scotchbond Universal Plus (RXU/SUP) and Panavia SA Universal/Clearfil Universal Bond Quick (PSU/CUQ), the later serving as a control with an aryl-sulfinate activator. Coronal dentin specimens were prepared (n = 5/material), treated with the corresponding primers/adhesives (non-irradiated) and covered with a 100 μm-thick RLA layer (SC+A group).