Dental Materials Commons^™

Color Stability, Physical Properties And Antifungal Effects Of Zro2 And Tio2 Nanoparticle Additions To Pigmented Polydimethylsiloxanes, Mazen Alkahtany

Theses & Dissertations

Introduction: Color changes, physical degradation and fungal infections are potential challenges to the longevity of polydimethylsiloxane (PDMS) elastomers. The purpose of this study was to evaluate potential improvements in color change, physical properties and anti fungal properties of PDMS loaded with TiO2 and ZrO2 nanoparticles.

Methods: 1% weight of 40 nm or 200 nm diameter TiO2 or ZrO2 nanoparticles were mixed into PDMS with 2% functional intrinsic yellow pigment and polymerized. Control materials contained 13% weight 200 nm silica. Samples were exposed to either 3000 hours of UVB radiation (200 μW/cm2) or darkness. Color parameters L*a*b* and ΔE*, ultimate tensile …

In Vivo Measurement Of Color Relationships Between The Maxillary Central Incisor And Canine As A Function Of Age, Marie E. Falcone

Master's Theses

Abstract

Introduction

It has long been taught that the basic shade (hue) of the patient can be taken from the canine (i.e. that tooth thought to have the highest chroma of a particular hue) and then that hue can be applied to other anterior teeth but at a lower chroma. However, this concept does not appear to derive from published measurements or observations. This study documented the color relationship between in vivo maxillary central incisors and canines to examine: (1) whether they share the same hue, but have different chromas (as commonly taught); and, (2) whether color differences (∆E values) …