Wear of ten dental restorative materials in five wear simulators--results of a round robin test.
OBJECTIVE
The purpose of the present study was to prove the hypothesis that different wear measurement methods generate different material rankings.


METHODS
Ten restorative materials, eight composites (BelleGlass, Chromasit, Estenia, Heliomolar RO, SureFil, Targis cured at 95 and 130 degrees C, Tetric Ceram) an amalgam (Amalcap) and a ceramic (Empress) have been evaluated with regard to the wear with five different wear methods (IVOCLAR, ZURICH, MUNICH, OHSU, ACTA). Every center received specimens, which Ivoclar Vivadent had made using the same batch. The test centers did not know which brand they were testing. After completion of the wear test, the raw data were sent to IVOCLAR for further analysis. The statistical analysis of the data included logarithmic transformation of the data, the calculation of relative ranks of each material within each test center, measures of agreement between methods, the discrimination power and coefficient of variation of each method as well as measures of the consistency and global performance for each material.


RESULTS
Relative ranks of the materials varied tremendously between the test centers. When all materials were taken into account and the test methods compared with each other, only ACTA agreed reasonably well with two other methods, i.e. OHSU and ZURICH. On the other hand, MUNICH did not agree with the other methods at all. The ZURICH method showed the lowest discrimination power, ACTA and IVOCLAR the highest. Materialwise, the best global performance was achieved by Empress, which was clearly ahead of BelleGlass, SureFil and Estenia. In contrast, Heliomolar RO, Tetric Ceram and especially Chromasit demonstrated a poor global performance. The best consistency was achieved by BelleGlass and SureFil, whereas the consistency of Amalcap and Heliomolar RO was poor.


CONCLUSIONS
As the different wear simulator settings measure different wear mechanisms, it seems reasonable to combine at least two different wear settings to assess the wear resistance of a new material.
Heintze
S D
SD
R&D, Ivoclar Vivadent AG, Bendererstrasse 2, FL-9494 Schaan, Liechtenstein. siegward.heintze@ivoclarvivadent.com
Zappini
G
G
Rousson
V
V
D000180:Acrylic Resins / Q000737:chemistry; D000538:Aluminum Silicates / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry; D003723:Dental Amalgam / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D019554:Dental Restoration Wear / Q000145:classification*; D005899:Glass Ionomer Cements / Q000737:chemistry; D006801:Humans; D008422:Materials Testing / Q000379:methods; D008689:Methacrylates / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D012823:Silicate Cement / Q000737:chemistry; D014520:Urethane / Q000737:chemistry
D000180:Acrylic Resins; D000538:Aluminum Silicates; C029012:Composite Dental Resin; D003188:Composite Resins; D003764:Dental Materials; D005899:Glass Ionomer Cements; C513708:Heliomolar; C075815:IPS-Empress ceramic; D008689:Methacrylates; D011140:Polyurethanes; C403464:SureFil packable composite; C121818:Tetric ceram; C513703:Vivadent; C110370:belleGlass; C113531:chromasit; C111282:dental polyglass; C091839:urethanetrimethacrylate; D003776:Dental Porcelain; D012823:Silicate Cement; D014520:Urethane; C041332:amalcap; D003723:Dental Amalgam