Modification of heat cured acrylic resin by using additives to make a flexible acrylic resin denture base material: A pilot study

that the dimensional accuracy, water sorption and solubility tests of the groups (caramel + plasticizer + heat cured acrylic resin) had statistically lower changes than other groups with additives but were still higher than control group and Flexite thermoplastic during seven days. they also showed color change between groups. the first group (caramel + plasticizer + heat cured acrylic resin) with the concentration of 20% showed lowest change in their properties when compared with the plasticizer group and the other groups of flavors additions (caramel and banana) after seven days and six months. conclusions: Within the limitation of this research, it was concluded that all prepared samples with additives (caramel, banana, and plasticizer) have better properties than the control group except the Flexite thermoplastic group which showed to have a higher tensile strength than control group during the periods of two and seven days

The influence of a new irrigant solution on the apical microleakage of obturated root canals

ABSTRACT Aims: The aim of this study was to evaluate the effect of a new endodontic irrigant solution (mixture of coconut and bromelain) on apical microleakage of obturated root canals. Materials and Methods: Forty roots were randomly divided into two groups (n = 20) according to the irrigant used. Group I (NaOcl &EDTA) andGroup II (mixture of coconut & bromelain). All roots were prepared with protaper Ni Ti rotary instrument to size F3. After completion of root canal preparation for both groups, the root canals were obturated using F3 gutta percha and resin sealer.The canal orifices were sealed with light cured composite resin. All roots were placed in 100% humidity and incubated at 37 C for 3 days to allow complete setting of the sealer.The root surfaces were coated by double layer of nail varnish except the apical 2mm and immersed in 2% methelyne blue for 48 hours. After that all roots were thoroughly washed under running water and allowed to dry, then the nail varnish was removed. The roots were split into 2 halves and the linear extent of dye penetration from the apical root ends were measured. Results: Statistical analysis revealed that there was no significant difference in apical microleakage between group I and group II. Conclusion: The apical microleakage of root canals irrigated with the new irrigant solution(mixture of coconut and bromelain) was comparable to that for root canals irrigated with NaOCl and EDTA

Experimental Modelling wax preparation from Petroleum products and natural additives Running Title: Preparation Experimental Modeling Wax

Introduction: Many modelling waxes are composed of complicated mixture of many constituents. Aims of the study: To modify Petroleum Iraqi natural waxes (hard and soft paraffin wax, natural and commercial beeswax) by adding some natural (gum Arabic, rosin, Na-CMC, starch, and amaranth) and chemical (ferric oxide) to prepare ne