Evaluation Of The Replication Capability Of Six Elastic Impression Materials

Presently, alginate impression and synthetic rubber impression are principally used for moulage material application, from plenty kinds of the oral impression material with many scarcities for each synthetic rubber impression mostly include silicone rubber, polyether rubber, polysulfide rubber and so on, among which, silicone rubber and polyether rubber are elastic body impression material. On clinical works, accurate moulage Is one of the preconditions and the key to successful restoration. Acquisition of accurate moulage not only lies on physician's skill, but also rests with choice of moulage material. Moulage material with high or low quality would impact restoration's quality. Consequently, moulage material should be selected discreetly, and elastic body impression material has many excellent physical and chemical capabilities: high intension, great elasticity, good fluidity, steady size, high precision and not to exchange with model material, so it is the best among all the moulage material, and is used abroad on domain of clinical restoration. So this task studied by comparing many kinds of familiar elastic body impression materials, and got a lot of real data offering reference for clinical application. This experiment uses 6 types of elastic body impression materials include Impregum- Penta polyether rubber(3M company) ; Express hydrophobicity addition silicone rubber(3M company);Silagum hydrophilic addition silicone rubber(DMG company), Aquasil hydrophilic addition silicone rubber(DMG company), EXAFINE hydrophilic addition silicone rubber(FUJI company); Zetaplus hydrophilic Kondens silicone rubber(Zhermack company). The purpose of this study was to evalute the changes in the wettability of 6 types of elastic body impression materials after immersion of disinfectant solution, and test the principal clinical application index—dimensional stability and preliminary assess the success ability of copying the tooth cervical margin.The results are showed as below:1. All these elastic body impression materials tested has no significant deviation on the success ability of copying the tooth cervical margin.2. The contact angles of 6 kinds elastic impression materials have not significant deviation. The contact angles of polyether rubber and 4 kinds hydrophilic silicone rubber after immersion of disinfection have increased tendency with extended soak time, but the wettability have degrade. But traditionary hydrophobicity silicone rubber has not this tendency.3. These elastic body impression materials after immersion disinfection in different time make the gypsum casts. The Express hydrophobicity addition silicone rubber is relatively the most accurate one after disinfection for 20 minters. They have significant deviation when it soak after 40 minters.