All ETDs from UAB

Advisory Committee Chair

Chin-Chuan Fu

Advisory Committee Members

Daniel Givan

Amjad Javed

Nathaniel Lawson

Wen-Chou Wu

Document Type


Date of Award


Degree Name by School

Master of Science (MS) School of Dentistry


Statement of Problem: The resin for 3D printing permanent crowns is a recently approved material with limited literature evidence to support its in vitro properties. Comparing the mechanical properties such as fracture load (N) and wear resistance for 3D printing permanent restorations resins would represent a very good reference to consider future clinical decisions. Purpose: To investigate the fracture load (N) and wear resistance of the resins for 3D printing permanent crowns available in the U.S. dental market and to compare amongst them using lithium disilicate as a reference. Materials and Methods: for the crown fracture test, the experimental design for crown fracture consisted of 8 groups, each group has 10 specimens. Each specimen was printed by using manufacturer instructions, except for the specimens of two materials; Flexcera and Rodin which were printed directly by the iv manufacturer since the fabrication process requires specific equipment that the biomaterials laboratory does not have. All the specimens were cemented with the following protocol. Eight specimens of each group were evaluated for the wear resistance using the wear resistance protocol by the department of Biomaterials from the University of Alabama at Birmingham, School of Dentistry was used. Results: For the crown fracture test, A One-way ANOVA revealed no significant difference in the fracture load (N) between the groups: lithium disilicate (Emax) (777.35 N), flexcera smile ultra (720.56 N), sprint ray crown (707.70 N), and rodin (646.19 N). On the other hand, the fracture Load for nextdent (1017.39 N) Onx tough (1211.53 N) and OnX (1555.04 N) were found to be significantly different. Regarding the wear test: the One-way ANOVA revealed that there is statistically significant difference between the lithium disilicate group and all the other groups. The groups onx, onx tough, sprint ray crown showed significant difference than rodin, flexcera and nexdent. Conclusions: The fracture load for nexdent, onx and onx tough was greater than the fracture load that lithium disilicate showed. The wear on lithium disilicate was statistically different than the wear in all the other materials.

Included in

Dentistry Commons



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.