All ETDs from UAB

Advisory Committee Chair

John O Burgess

Advisory Committee Members

Amjad Javed

Nathaniel C Lawson

Jack Lemons

Augusto Robles

Document Type

Thesis

Date of Award

2017

Degree Name by School

Master of Science in Dentistry (MScD) School of Dentistry

Abstract

ABSTRACT Objectives: Bioactive materials release calcium, phosphate, and fluoride which may increase tooth remineralization. But limited data is available demonstrating the superiority of bioactive or ion releasing materials compared to fluoride or no ion releasing materials. The aims of the present study are to measure and compare the calcium, fluoride, and phosphate ion release at different pH, flexural strength and caries protecting ability of the materials including the ion uptake of surrounding tooth structure. Methods: Activa, Cention N, Fuji LC II and Filtek Supreme Ultra were the restorative materials tested. Firstly, the fluoride and calcium release of these materials was measured using ion specific electrode at 24 hours, 1 week, 1 and 3, month intervals in deionized water(pH=7.0) and acidic solution(pH=4.0). Secondly, the flexural strength of the materials was measured at 24 hours, 1 week, 1 and 3 Month intervals. Thirdly, the efficacy of these materials to prevent demineralization in an artificial caries solution was measured and compared. 20 freshly extracted non-caries teeth (examined at 30x) (n=10) with class V preparations on the mesial and distal surfaces were randomized and restorations with each restorative material were placed. The restored teeth containing these materials were placed into an artificial caries solution for 72 hours with constant stirring and the teeth were sectioned and viewed with polarized light to measure demineralization at the restorative material tooth interface. Three random sections from each specimen used in the artificial cares section were examined to determine the elemental analysis using X-ray photoelectron spectroscopy. The data obtained was analyzed using linear mixed model with first-order autoregressive covariance structure for calcium and fluoride ion release, while data for flexural strength and artificial caries was analyzed using a ANOVA followed by Tukey post hoc analysis. Results: Deionized water and acidic solutions produced different calcium and fluoride ion release from the different materials were statistically different in except for Filtek Supreme Ultra. (p≤ 0.0001) The calcium ion release of Activa and Fuji II LC and the fluoride ion release of Cention N and Fuji II LC were not statistically significant difference. At all 4-time points, except for Filtek Supreme Ultra, all materials showed statistically significant different release rates (p≤ 0.0001). The interaction of flexural strength and time of all 4 materials was statistically not significant (p≥0.0001) while when within materials comparison demonstrated that the flexural strength of Cention N and Activa is not significantly (p≤ 0.0279) similar. Analyses of the artificial caries lesions revealed no statistically significant difference in surface area of artificial caries lesions for all the 4 materials in enamel, but in dentin surface areas of the lesion significantly differ. (p ≤ 0.0001) Conclusions: In solution, Cention N released significantly more calcium than all other materials. The RMGI Fuji II LC fluoride release and the caries protection ability were not significantly different than Cention N. Cention N has the ion release favoring possible remineralization.

Included in

Dentistry Commons

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.