RESUMO
Extrusion printing based on biocompatible filaments offers a wide variety of targeted medical and dental applications in the area of personalized medicine, if combined with bioactive nanomaterials. However, this requires filament to be coated with bioactive nanomaterial. This study introduces a concept of a machine to coat filament with bioactive nanomaterials and its application. A machine was constructed with modules manufactured using additive manufacturing. A filament spool of polylactide (PLA) or glycol-modified polyethylene terephthalate (PETG) was transported through a copper tube, with the outer surface of the filament heated to the appropriate glass transition temperature to incorporate added nanomaterials such as nano-hydroxyapatite (nHA) or nano-fluorapatite(nFA). Coatings with nHA led to an increase in diameter of around 3 µm, while coatings with nFA increased the diameter by 4 µm. Printing of cubes with a standard extrusion printer platform using PLA or PETG filaments with added nHA or nFA has been successfully carried out. Scanning electron microscope (SEM) images of coated filaments and printed cubes showed an irregular distribution of nHA or nFA, which could be verified by energy dispersive X-ray analysis (EDX). Adding and adjusting bioactive nanomaterials to filament with a coating machine for filament proved to generate printable filaments. With the wide range of possible applications by different nanomaterials it is anticipated that extrusion printing can cover needs for personalized medicine and dentistry.
RESUMO
Aim: To establish the inter-rater reliability of the Composite Quality Score (CQS-2) and to test the null hypothesis that it did not differ significantly from that of the first CQS version (CQS-1). Materials and methods: Four independent raters were selected to rate 45 clinical trial reports using CQS-1 and CQS-2. The raters remained unaware of each other's participation in this study until all rating had been completed. Each rater received only one rating template at a time in a random sequence for CQS-1 and CQS-2 rating. Raters completed each template and sent these back to the principal investigator. Each rater received their next template 2 weeks after submission of the completed previous template. The inter-rater reliabilities for the overall appraisal score of the CQS-1 and the CQS-2 were established by using the Brennan-Prediger coefficient (BPC). The coefficients of both CQS versions were compared by using the two-sample z-test. During secondary analysis, the BPCs for every criterion and each corroboration level for both CQS versions were established. Results: The BPC for the CQS-1 was 0.85 (95% CI: 0.64-1.00) and for the CQS-2 it was 1.00 (95% CI: 0.94-1.00), suggesting a very high inter-rater reliability for both. The difference between the two CQS versions was statistically not significant (p = 0.17). The null hypothesis was accepted. Conclusion: The CQS-2 is still under development, This study shows that it is associated with a very high inter-rater reliability, which did not statistically significantly differ from that of the CQS-1. The promising results of this study warrant further investigation in the applicability of the CQS-2 as an appraisal tool for prospective controlled clinical therapy trials.