Polymerization Stress Tester

The shrinkage that accompanies curing of dental composites is one of the leading drawbacks of this type of restorative material. A variety of differing testing methods have been tried over the years to measure this shrinkage and the stress that it leads to. But these methods have been difficult to use and involve highly specialized devices. Now Proto-tech has developed a new system that can accurately measure polymerization stress and shrinkage easily and affordably.

Based on the cylindrical testing geometry pioneered at ACTA and improved at OHSU, the Proto-tech polymerization stress tester uses a precision positioning table driven by a stepping motor and controlled by custom software. The preparations for each specimen are quick and easy to perform. A 200N load cell senses the polymerization stress, and the level of compliance correction can be adjusted up to 100% compensation for compliance of the load cell. The up and down motion of the positioning table is controlled through a command module. The testing program can be set to measure either the polymerization stress or the polymerization shrinkage of the composite. The testing fixtures allow for light curing to be directed to both the top and bottom sides of the specimen.

View our poster from Pan European IADR, 2002, Cardiff (.pdf)

Proto-tech                                  Ph: (971) 344-3730
15571 SE Oatfield Rd               Fax:(503) 786-0842
Portland, OR 97267                  Email: info@oralwear.com 

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