Author(s):
1. Valentina Veselinović, University of Banja Luka, Medical Faculty, Republic of Srpska, Bosnia and Herzegovina
2. Nataša Trtić, Republic of Srpska, Bosnia and Herzegovina
3. Tijana Adamović, Medicinski fakultet Banja Luka , Republic of Srpska, Bosnia and Herzegovina
4. Rebeka Rudolf, University of Maribor, Faculty of Mechanical Engineering, Slovenia

Abstract:
INTRODUCTION: The addition of gold nanoparticles to the acrylic material for the prosthesis base is one of the currently most attractive directions in the improvement of the mechanical and biological properties of this kind of material. However, the real success of prosthetic therapy can be interprets from two distinct points: its functional and aesthetic aspect. To date, there are no studies that dealt with the aesthetic parameters of the color change of acrylic material for prosthesis after its modification with gold nanoparticles. AIM: The aim of this study was to investigate the influence of addition of different concentrations of gold nanoparticles (AuNPs) produced by Ultrasonic Spray Pyrolysis (USP) on color parameters of nanomodified PMMA prosthesis base material as well as their mutual comparation. MATERIAL AND METHOD: In our investigation we used gold nanoparticles (GNPs) produced by new technologies - Ultrasonic Spray Pyrolysis (USP) method, from the precursor solution from Au (III). The addition of highly dispersed gold nano-particle (AuNP), in polymethyl methacrylate (PMMA) ProBase Hot Monomer, IvoclaVivadent, Liethenstein, followed by the formation of nanomodified polymer composite are performed in special manner. Four groups of samples by uniform dimensions of 50 x 50 x 4 mm, and with different AuNPs concentration (PMMA-AuNP1 0,12%, PMMA-AuNP2 0,43%, PMMA-AuNP3 0,74% and control group) were performed. The color evaluation and its change were performed by a spectrophotometer Datacolor SF600 plus and through the CIELab (Commission Internationale de l'Eclairage) system. The color change definition (ΔE * ab) was made based on CIE L *, and *, and b *. RESULTS:The color values show that L * (light) PMMA-AuNP1 sample is slightly lower than the base sample, while the PMMA-AuNP2 and PMMA-AuNP3 have a higer values. The basic sample has the highest C * value, so it is the most saturated (most colourful). The basic sample also has the highest value of b * (more yellow shades), while the other three samples have a lower b * value (more blue shades). Also, the color angle h is smaller then the basic one for all three samples (closer to the red colour axis a +). Color changes in base resins were significantly affected by addition of gold nanoparticles (p<0.05). The colour differences ΔE * are in the range from 2,6 – 4,9. CONCLUSION: This study supports the impression that a strong relationship exists between addition of gold nanoparticles and their concentration on colour change of acrylic prosthesis base material what strongly correlating with esthetic aspect of prosthetic therapy.

Key words:
gold nanopartcles,ulrasonic spray pirolisis,denture base,Polymethylmethacrylat,color properties,spectrophotometer,CIE Lab

Thematic field:
SYMPOSIUM B - Biomaterials and nanomedicine

Date of abstract submission:
16.07.2018.

Conference:
Contemporary Materials 2018 - Savremeni Materijali

Applied paper from author