Comparative evaluation of marginal accuracy of different provisional restorative materials fabricated by direct technique: An in vitro study

Objective: The most essential requirement of a provisional crown is an adequate marginal fit which necessary for maintaining optimal periodontal health and protect the tooth from physical, chemical, thermal, bacterial injuries. purpose this in vitro study was to evaluate compare vertical accuracy materials using four different material systems (Autopolymerized PMMA powder-liquid system, light-activated UD single paste chemically activated Bis-GMA two auto mix system dual cure polymerized resin system) direct technique. Materials Methods: Two customized stainless-steel dies, simulating prepared unprepared were used fabricated total no. 48 crowns. A vacuum-formed polypropylene sheet as matrix. Twelve crowns, each (n = 12 × 4) analyzed by stereomicroscope 20X magnification at points.