Exploring the Physicochemical, Mechanical, and Photocatalytic Antibacterial Properties of a Methacrylate-Based Dental Material Loaded with ZnO Nanoparticles.

While resin-based materials meet the many requirements of a restorative material, they lack adequate, long-lasting antimicrobial power. This study investigated a zinc oxide nanoparticle (ZnO NP)-loaded resin-blend (RB) toward a new antimicrobial photodynamic therapy (aPDT)-based approach for managing dental caries. The results confirmed that up to 20 wt% ZnO NPs could be added without compromising the degree of conversion (DC) of the original blend. The DC achieved for the 20 wt% ZnO NP blend has been the highest reported. The effects on flexural strength (FS), shear bond strength to dentin (SBS), water sorption (WS), solubility (SL), and viability of Streptococcus mutans under 1.35 J/cm2 blue light or dark conditions were limited to ≤20 wt% ZnO NP loading. The addition of up to 20 wt% ZnO NPs had a minimal impact on FS or SBS, while a reduction in the bacteria count was observed. The maximum loading resulted in an increase in SL. Furthermore, 28-day aging in 37 °C water increased the FS for all groups, while it sustained the reduction in bacteria count for the 20 wt% resin blends. Overall, the ZnO NP-loaded resin-based restorative material presents significant potential for use in aPDT.

The antimicrobial, physical, and chemical properties of a riboflavin-loaded dental resin intended for antimicrobial photodynamic therapy.

BACKGROUND: Dental caries remain a significant global health challenge. Unfortunately, current dental materials lack sufficient antimicrobial power to address the pathogenic species involved in this disease. In this study the potential to load a dental resin blend (RB) with riboflavin (B2) for use in an antimicrobial photodynamic therapy (aPDT) approach was investigated. METHODS: B2 was added to our experimental RB (0.1 - 10 wt%). Upon investigating the degree of conversion and specimen integrity of the RB as a function of B2 concentration, it was determined that loading should be restricted to 0.1, 1.0, and 1.5 wt%. Subsequent investigation included water sorption (WS) and solubility (SL), as well as shear bond strength (SBS) and flexural strength (FS) of the specimens after 24 h and 28-day water storage. Lastly, the antimicrobial response of Streptococcus mutans (S. mutans) biofilm following 6 h growth and 60 s of blue LED light (1.3 J/cm2) in an aPDT-based approach was measured. RESULTS AND CONCLUSIONS: Adding up to 1.5 wt% B2 had minimal impact on the FS or SBS of the RB. However, aging for 28-days notably increased the FS by as much as 50% for the 1.5 wt% B2-loaded RB. In addition, adding 1.5 wt% B2 resulted in a significant reduction in WS/SL of the RB. Lastly, while adding B2 did not change the antimicrobial response, this was an initial study under these conditions and future investigation will seek to optimize light parameters to produce a more agonistic response. Overall, a riboflavin-loaded dental resin shows significant promise for utilization in restorative dentistry with aPDT.

Developing the Synergy Model Patient Acuity Tool for Admission, Discharge, and Transfer.

BACKGROUND: The Admission Discharge Transfer-Synergy Model Acuity Tool (ADT-SMAT) was developed to quantify patient intervention intensity and patient response variability and to capture nurses' critical thinking. The tool is based on the American Association of Critical-Care Nurses Synergy Model for Patient Care. OBJECTIVE: To determine whether the ADT-SMAT is reliable and valid for predicting the level of care for admission, discharge, and transfer of critically ill patients. Methods Reliability was examined by using interrater reliability, intraclass coefficient, and effect size analyses to evaluate physiological variables and total calculated ADT-SMAT score in 246 patients. Content validity was determined in consultation with critical care nurses, and construct validity was examined by assessing the correlation between ADT-SMAT scores and other convergent and divergent constructs. RESULTS: The ADT-SMAT showed strong reliability for measuring the physiological variables and total score, with an intraclass coefficient of 0.930. The value of Cohen d determining the effect size for each element of the ADT-SMAT was less than 0.20 for every element, indicating that substantial differences in scoring did not occur. The validity of the ADT-SMAT requires additional testing. CONCLUSIONS: This is the first study attempting to correlate Synergy Model patient characteristics and acuity while integrating nurses' critical decision-making process. With further testing, the ADT-SMAT could be a valuable tool to quantify and standardize patient characteristics in determining the appropriate level of care associated with admission, discharge, and transfer decisions.

Correction: Synthesis of α,ß-unsaturated esters of perfluoropolyalkylethers (PFPAEs) based on hexafluoropropylene oxide units for photopolymerization.

[This corrects the article DOI: 10.1039/C8RA06354K.].

Synthesis of α,ß-unsaturated esters of perfluoropolyalkylethers (PFPAEs) based on hexafluoropropylene oxide units for photopolymerization.

α,ß-unsaturated esters are usually synthesized for polymer applications. However, the addition of maleate (cis-configuration) to a fluorinated moiety is challenging due to its potential isomerization during esterification. Various synthetic routes were attempted and led to very low conversion or side-products. The immiscibility of both reagents combined with an easy isomerization or attack on the double bond were potential explanations. In this paper, the synthesis of maleates oligo(hexafluoropropylene oxide) is reported by Steglich esterification and the reaction conditions are discussed depending on the molecular weight of the fluorinated moieties. After UV-curing, hydrophobic polymers were obtained by copolymerization with vinyl ethers by electron acceptor-donor systems.