Student Theses, Dissertations and Capstones

Document Type

Thesis

Degree Name

Master of Science (M.S.) in Dentistry

Copyright Statement

All rights reserved. This publication is intended for use solely by faculty, students, and staff of Nova Southeastern University. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, now known or later developed, including but not limited to photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the author or the publisher.

Department

College of Dental Medicine

First Advisor

Cristina Garcia-Godoy

Publication Date / Copyright Date

2018

Publisher

Nova Southeastern University

Abstract

Background: Dental ceramics have been chosen as the material of choice by patients and clinicians because of their aesthetics, color stability, and low thermal conductivity. Clinically, almost all restorations need some adjustments to allow adequate occlusion and contacts. However, these adjustments will create rough surfaces. Therefore, different surface treatments have been developed to improve surface smoothness and gloss of dental ceramics. Objective: To evaluate the average surface roughness (Ra) and gloss (GU) of three different monolithic ceramics: Lithium Disilicate (IPS e.max CAD), Leucite reinforced (IPS Empress CAD) and Feldspathic (Vitablocs Mark II) subjected to two different surface treatments (mechanical polishing vs reglazing firing procedure). Material and methods: Ten disc-shaped samples (10-mm diameter and 2-mm thick) of each ceramic were prepared, for a total of 60 samples. Ceramics were CAD designed by E4D Technologies and milled to size specification. Then, specimens were glazed following manufacturer’s recommendation and fired in a furnace. A fully adjustable device was used to hold the hand piece to have a standardized pressure. After adjustment, specimens were randomly assigned to one of the surface treatment options: mechanical finishing and polishing by Dialite LD System; or reglazing firing procedure using Enamelite Low-Fusing Ceramic Spray Glaze. A surface profiler was used to assess the surface roughness and gloss values were measured using a gloss meter. Results: Post-hoc tests were conducted using a Bonferroni adjustment. R Studio and R 3.2.2 was used for all statistical analysis, and significance was accepted at p < 0.05. Post-hoc Tukey results indicate mechanical polishing had a significantly lower Ra average than reglazing firing procedure (difference = 1.51, 95% CI:1.27,1.75]. Post-hoc Tukey results indicate reglazing firing procedure had a significantly higher GU average than mechanical polishing (difference = 15.01, 95% CI:14.04,15.96]. Conclusion: All tested CAD/CAM monolithic ceramics presented smoother surfaces and higher gloss at baseline than after subjected to adjustment and surface treatments.

Disciplines

Dentistry

Files

Download

Download Full Text (3.5 MB)

Included in

Dentistry Commons

 
COinS