Mechanical strength and durability of some newly developed compomeres.

FISCHER J, MARX R. (Klinik für Zahnerhaltung, Parodontologie und Präventive Zahnheilkunde und Lehr- und Forschungsbereich für Zahnärztliche Werkstoffe, Klinik für Zahnärztliche Prothetik, Medizinisch Fakultät der RWTH Aachen)


Compomeres, discussed as new filling materials and possibly useful in non-stress bearing areas of tooth or in primary teeth, are light-curing compositions of glass ionomer cements and composites.

Their clinical effectiveness depends on the mechanical parameters abrasion rate, bend strength, fracture toughness and long-time durability. In this study some of these parameters have been examinated for ARTGLASS® (Heraeus Kulzer), DYRACT® (DeTrey) and COMPOGLASS® (Vivadent) and compared with those of a composite CHARISMA® (Heraeus Kulzer). The bend strength was tested in the three point bending test (sample size 1.5 x 3 x 24 mm), the fracture toughness in the four point bending test of fracture mechanics (sample size 6 x 3 x 30 mm). The durability was examined by storage of the samples in a corrosive bath up to 150 days before proof testing. The fracture toughnesses and bend strengthes of DYRACT were determined as 1.35±0.1 MPa*m3/2 and 77.95±21.5 MPa; for COMPOGLASS 1.43±0.2 MPa*m3/2 and 74.4±11.3 MPa; for ARTGLASS 1.97±0.19 MPa*m3/2 and 108.68±8.7 MPa, respectively. This values are to be compared with the parameters of CHARISMA: 2.8±0.27 MPa*m3/2 and 128.3±7.7 MPa, respectively.

As a result we come to the conclusion that the newly developed compomere materials may be useful when the indication is strictly limited to fillings for cavity classes I, III, V, primary teeth and to preprosthetic tooth stump-set up.