Posterior palatal base distortion of ProBase Hot versus the conventional heat curedacrylic resin before and after water immersion

Objectives; This study was carried out to compare the posterior palatal base distortion of denture bases processed with ProBase Hot to those processed by conventional heat cure acrylic resin (Acrostone) before and after water immersion. Study design; Twenty waxed denture bases were prepared for U-shaped palatine arch form, ten for each denture base material. Waxed denture bases were flasked, packed and processed according to the manufacturer ’ s instructions. Immediately after decasting, the dentures were repositioned on their corresponding casts to measure the amount of gap formed between denture base and cast at 5 points along the posterior border of denture base using a measure scope. Denture bases were stored in tap water for 4 weeks then the same test was repeated. Results; This study demonstrated a posterior palatal base discrepancy for both materials particularly at the center of the palate. ProBase Hot showed better results than that of the conventional acrylic resin. Regarding water sorption, all the tested groups showed significant posterior palatal base accuracy when stored in tap water for 4 weeks. Conclusions; ProBase Hot is a better choice for constructing denture bases to compensate for the increased distortion due to palatal shape.