Development of a Gripping Fixture for Micro-Tensile Testing of Bonded Ceramic Dumbbells

It is proposed that both the adhesive interface geometry and the mismatch of elastic moduli influence the tensile strengths of dental bonds attaching restorative ceramics to dentin. Prior calculations indicate this to be due to peripheral interface stress singularities. A physical testing approach to examine and validate the theoretical conclusions utilizing a microtensile testing system is presented. Considering the choice of shear versus tensile and then macro versus micro tensile testing, reasons were identified for choosing micro tensile testing. Specimen dimensions and shapes were developed to optimize the adjustment of the interface geometries and information that could be obtained therein. Here a dumbbell structure is best suited to the testing needs. Dumbbell specimens were first fabricated using the ceramic press technique, and then mini-CNC machining. Specimens fabricated by each technique were examined, showing that the mini-CNC machining methodology was superior. Significant problems in instrumentation were overcome by the design and fabrication of two testing fixtures: 1. A collet based design with independent upper and lower mechanical grips for each end of the dumbbell, to be used in conjunction with a loading device; 2. A screw based clamping design similar to previous jigs, using two screw clamps on V-channels connected by sliding rods. Testing revealed that the collet-based design shows the most promise because of its distributed gripping load. Further tests that can evaluate the effectiveness of this device for microtensile testing are outlined.

Grantor dc:publisher

State University of New York at Buffalo

Year dc:date.issued

2018

Author dc:creator

• Makowka, Steven

Contributors dc:contributor

• Baier, Robert
• Biomaterials

• dentistry
• mechanical engineering
• mechanics

Statement dc:rights

• Users of works found in University at Buffalo Institutional Repository (UBIR) are responsible for identifying and contacting the copyright owner for permission to reuse. University at Buffalo Libraries do not manage rights for copyright-protected works and cannot assist with permissions.
• Copyright retained by author.

Language dc:language

eng

Handle dc:identifier

http://hdl.handle.net/10477/77966

OAI record oai:identifier

https://ubir.buffalo.edu/oai/request?verb=GetRecord&metadataPrefix=qdc&identifier=oai%3Aubir.buffalo.edu%3A10477%2F77966