Ceramics are widely used in dental and orthopedic prostheses because of their aesthetics, inertness, and biocompatibility. However, ceramics are vulnerable to fracture which accounts for millions of dollars annually in replacement costs and can cause significant patient discomfort and loss of productive lifestyle. Our preliminary investigations have established relations between failure modes and crown thickness, surface conditions, properties of the ceramic, and loading conditions. These findings indicate that monolithic glass- ceramic crowns and veneered alumina crowns are vulnerable to both near-contact occlusal damages and cementation internal surfaces radial fractures, while the veneered Y-TZP crowns are prone to veneer fracture owing to the superior strength of zirconia frameworks. These findings are consistent with clinical reports. It is the fracture problem of ceramic prostheses that motivated us to develop a new generation of damage resistant ceramic prostheses utilizing functionally graded materials. Recent theoretical and experimental advances demonstrate unprecedented resistance to contact damage in functionally graded materials that otherwise cannot be realized in conventional homogeneous materials. Our long-term goal is to develop an aesthetic, strong, thin zirconia based functionally graded material for less invasive all-ceramic posterior crowns and bridges, foreshadowing possibilities for orthopedic and other engineering applications. The objective of this proposal is to fabricate and validate the contact and flexural damage resistances of ceramic layer structures with continuous gradation from both top and bottom surfaces. We propose to achieve this objective through two specific aims: 1. Develop and characterize a new glass/zirconia/glass composite with continuous elastic modulus gradation from outer surfaces (low modulus glass-ceramic) to interior (strong, dense, fine-grain zirconia); and 2. Optimize the function-property (aesthetics, damage resistance-microstructure) relation of glass/zirconia/glass subjected to cyclic loading in water. Our preliminary studies have demonstrated that a functionally graded glass/zirconia/glass sandwich structure with improved damage resistance and aesthetics compared to their bulk zirconia counterparts can be produced by infiltrating a low elastic modulus glass-ceramic into the surfaces of a presintered zirconia. Relevance to public health: Knowledge generated from this investigation will guide design of a new generation of functionally graded ceramic dental and orthopedic prostheses with improved lifetime by resistance to contact damage and flexural fatigue, reducing morbidity and costs of replacement to the public. ? ? ?

Agency
National Institute of Health (NIH)
Institute
National Institute of Dental & Craniofacial Research (NIDCR)
Type
Research Project (R01)
Project #
1R01DE017925-01A1
Application #
7315458
Study Section
Oral, Dental and Craniofacial Sciences Study Section (ODCS)
Program Officer
Drummond, James A
Project Start
2007-09-01
Project End
2010-08-31
Budget Start
2007-09-01
Budget End
2008-08-31
Support Year
1
Fiscal Year
2007
Total Cost
$383,750
Indirect Cost
Name
New York University
Department
Dentistry
Type
Schools of Dentistry
DUNS #
041968306
City
New York
State
NY
Country
United States
Zip Code
10012
Han, Aifang; Tsoi, James K H; Matinlinna, Jukka P et al. (2018) Effects of different sterilization methods on surface characteristics and biofilm formation on zirconia in vitro. Dent Mater 34:272-281
Kim, Jeongho; Dhital, Sukirti; Zhivago, Paul et al. (2018) Viscoelastic finite element analysis of residual stresses in porcelain-veneered zirconia dental crowns. J Mech Behav Biomed Mater 82:202-209
Zhang, Y; Lawn, B R (2018) Novel Zirconia Materials in Dentistry. J Dent Res 97:140-147
Zhao, M; Sun, Y; Zhang, J et al. (2018) Novel Translucent and Strong Submicron Alumina Ceramics for Dental Restorations. J Dent Res 97:289-295
Chai, Herzl; Mieleszko, Adam J; Chu, Stephen J et al. (2018) Using glass-graded zirconia to increase delamination growth resistance in porcelain/zirconia dental structures. Dent Mater 34:e8-e14
Mao, L; Kaizer, M R; Zhao, M et al. (2018) Graded Ultra-Translucent Zirconia (5Y-PSZ) for Strength and Functionalities. J Dent Res 97:1222-1228
Fabris, Douglas; Souza, JĂșlio C M; Silva, Filipe S et al. (2017) THERMAL RESIDUAL STRESSES IN BILAYERED, TRILAYERED AND GRADED DENTAL CERAMICS. Ceram Int 43:3670-3678
Zhang, Yu; Kelly, J Robert (2017) Dental Ceramics for Restoration and Metal Veneering. Dent Clin North Am 61:797-819
Alao, Abdur-Rasheed; Stoll, Richard; Song, Xiao-Fei et al. (2017) Fracture, roughness and phase transformation in CAD/CAM milling and subsequent surface treatments of lithium metasilicate/disilicate glass-ceramics. J Mech Behav Biomed Mater 74:251-260
Chai, Herzl; Lawn, Brian R (2017) Fracture resistance of molar teeth with mesial-occlusal-distal (MOD) restorations. Dent Mater 33:e283-e289

Showing the most recent 10 out of 68 publications