A multifunctional device to simulate oral ageing: the "Rub&Roll".

UNLABELLED This article describes an in vitro fatigue and/or wear simulator enabling controlled application of force, speed, type of liquids and duration, to mimic challenges representative for the human oral environment. The device consists of a container in which a cylinder with specimen holder is placed which drives another cylinder (rod). The rod rotates in an opposite direction to the rotation of the stirring motor, rolling over the specimens mounted in the cylinder. When the rod contacts the specimen a force is applied to mimic processes in the oral environment. The design, working and construction principles of a new device, the Rub&Roll, and some of the possible applications are described Four different application examples are presented: occlusal wear in an low acidic abrasive slurry; combined erosive and abrasive wear of enamel exposed to apple juice or apple pulp; the wear of sealant material in natural teeth in an abrasive slurry; and the influence of mechanical loading cycles on micro tensile bond strength of an adhesive system to dentin Application of the "Rub & Roll" device showed results which are clinically relevant, reproducible and in accordance with existing literature. CONCLUSIONS The Rub&Roll enables controlled application of chemical and mechanical loading, allowing variation of force, sliding distance, velocity, number of cycles, and frequency, and a combination with erosive and abrasive challenges representative of those in the oral environment.