PURPOSE: This study recorded and compared the flexural elastic moduli and moduli of rupture of four materials (Provipont DC resin, Triad provisional restorative material, Jet acrylic resin, and a 50:50 mixture of Jet acrylic resin and orthodontic resin) used to make provisional restorations. MATERIAL AND METHODS: Thirty-nine identical 63 x 10 x 3 mm specimens were made from each of the four materials. After 24 hours, 30 days, and 60 days of water storage at 37 degrees C (13 specimens each), standard three-point bend tests were conducted on an Instron universal testing machine at a crosshead speed of 0.5 cm/minute. Stress strain curves were generated, and values for the flexural elastic moduli and moduli of rupture were calculated. Data were subjected to two-way and one-way analyses of variance (alpha = 0.05). RESULTS: Provipont DC resin exhibited significantly higher flexural elastic moduli and moduli of rupture values at the 24-hour test time. However, Provipont DC resin exhibited the greatest decrease in these values over time.