Stable record base is critical for recording an accurate maxillo-mandibular relationship and evaluation of the esthetics and phonetics of the wax trial prosthesis. To ensure intra-oral stability and retention of the record base, the base should maintain close adaptation to the cast and be dimensionally stable, this study compare the dimensional stability of visible light cure acrylic both conventionally and by using new technique of short curing cycle. Thirty maxillary cast edentulous models poured with a type IV dental di-stone, the specimen divided into three subgroups each group consist of ten cast. In the first group denture base constructed from heat cure acrylic resin using short curing cycle, while in the second group it constructed by using visible light cure acrylic resin and for the third group from visible light cure acrylic resin using new technique, the gap space occurs between the denture base and the cast measured by using traveling microscope measuring device. In this study the reading for the gap space occur between the denture base and the cast show that significantly both the short cycle and VLC new technique more dimensionally stable than that of VLC conventional technique when compared by ANOVA Table and LSD multiple comparison. The dimensional accuracy or fit for the denture base improved by using either a heat cured acrylic resin (using short curing cycle or by using light activated poly methylmethacrylate with the aid of new technique so that better stability and retention of the record bases obtained.

This research compares between the effect of flexible and hard stabilization splint (night guard, mouth guard) in the treatment of patients with tempro-mandibular joint problems.Four different categories of patients are used for comparison, each composed of ten patients. Category number one and two are treated with flexible mouth guard, while category three and four are treated with hard type of mouth guard for the same periods of time, one month and three months respectively. Analysis of the results indicate that patient category treated with soft stabilization splints for longer period of time show improved treatment and the patients are more relived and willing to continue the treatment than those treated with hard splints.