Details

Autor(en) / Beteiligte

• Heintze, S.D.
• Zellweger, G.
• Zappini, G.

Titel

The relationship between physical parameters and wear of dental composites

Ist Teil von

• Wear, 2007-09, Vol.263 (7), p.1138-1146

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

2007

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A wear method was developed that mainly simulates attrition wear using a commercially available chewing simulator (Willytec, Germany). In this test, a standardized stylus made of pressable ceramic (Empress) hits flat specimens 120,000 times with a 5 kg weight, a descent speed of 60 mm/s and a lateral movement of 0.7 mm with a speed of 40 mm/s under constant exchange of water at different temperatures (325 × 5 °C/55 °C). The volume loss was measured on plaster replicas with the Laserscan 3D (Willytec) and the Match 3D software. Twenty-four experimental and commercial composites ( n = 8) were tested with a volumetric wear range of between 5.5 and 147 × 10 −2 mm 3. On standardized specimens made of the same composites, the Vickers hardness ( H), elastic modulus ( E) and fracture toughness ( K 1c) were measured. The mean particle size ( d) and volume content ( v f ) of the inorganic filler were evaluated. Furthermore, a differentiation was made between the main filler with the largest mean size ( d 1, v f,1 ) and the total filler content ( v f , tot ). The best linear regression curve fit with an adjusted R 2 of 0.908 was found for wear   index = d 1 0.6 K 1 c v f , 1 v f , tot ( E / H ) . The good mathematical fit of the formula may be an indication that the wear method is based on physical properties and that it provides a highly reproducible standard.