Influence of different parameters during polishing: a pilot study with 10 dental technicians

The mirror finish during the CAM process is not possible yet nevertheless a high gloss surface is unavoidable, and therefore polishing with the aid of a dental hand piece is still important. We examined different parameters during the dental polishing process by ten different dental technicians concerning their individual way to work. How tall are the emerging contact forces, the emerging temperatures? How long does a dental technician take to polish a defined surface area? How is it to the different materials? Four different materials were tested. Three plastic interim arrangements: Zeno CAO temporary PMMA (Wieland Dental & Technik), Profix (Merz), CAD Temp (Vita), and one leucite ceramic Mark II (Vita). Every sample 10x8x2 mm was made out of cerec-blanks. In each case it was used a specific polisher in two graduations. A prepolisher and a mirror finish polisher. The plastic interim arrangements were polished with Technik Polierer medium and fine (EVE), the ceramic with Diapol medium and fine (EVE). The contact pressure was measured by a load cell (Lorenz K13) its measurement rang is 0,01N -10N, the accuracy is 0,5N. The surface temperature in direct nearness to the polishing process was detected by infrared and additionally the warming of the whole sample by direct contact measurement (Testo temp Sensor 845).The average contact force was determined and generated by ten dental technicians with 80 sample runs. It came up to 1.2 N. This study can be used for subsequent researches and standardized test conditions in the material science as an evaluated quantity. Schlagwörter: surface finishing, handpiece, polishing, CAD/CAM, Cerec, force, temperature, roughness