The replacement of classical fillings, especially in the posterior area with different types of inlays has become a common solution used in order to improve all parameters which insure a long lasting treatment. Vrious ceramic materials and systems are available, but so far an ideal ceramic material suited for all clinical situations, has not been found. The range of ceramic materials as: lithium disilicate, aluminum oxide, zirconium oxide and hybrid ceramics enhance the possibilities of using ceramic inalys in various clinical situations. Marginal adaptation is one of the most important conditions for long-term success for any type of material. The marginal discrepancy of fixed restorations is one of the main factors which lead to failure of the prosthetic treatment.The purpose of the present study is to compare a 2D and 3D method for evaluating the marginal fit for pressed lithium dislicate inlays (Emax). The two used methods were: SEM- electronic microscopy and micro CT.

The main goal of the present study is to compare the marginal fit of two different kind of pressed materials: a partially crystalline thermoplastic resin reinforced with ceramic particles (BioHPP) and lithium disilicate (EMax), through the use of the microCT technique. After extraction of four caries-free mandibular first molars, first class inlay cavities were prepared. For each tooth two inlays were manufactured- one by using BioHPP thermoplastic resin (n=4) and one by using Emax Press lithium disilicate (n=4). The marginal gap was analyzed circumferentially at the occlusal margin using a Bruker micro CT, by measuring the distance at the occlusal limit of the cavities, between the restoration and the tooth in several points for every surface of each tooth before cementing. Data were analyzed statistically using the Mann-Whitney U test and the Pearson�s correlation coefficient (a=0.05). A significant statistical difference was found between the marginal gap size obtained for BioHPP and Emax inlays (p[0.001). For the Emax inlays the marginal gap had an average of 72mm, while for BioHPP the average was 94 �m. Both types of used materials offer a good marginal adaptation. By summing up the gathered data we can conclude that the pressed ceramics shows a better marginal fit than the pressed resin, probably because of the different processing methods: sintering versus polymerizing with different shrinkage values.

The goal of the present study is to compare the marginal fit using microCT of ceramic inlays obtained using two different technologies: pressing technique (lithium disilicate) and milling technique (milled leucite glass-ceramic). After extraction of four caries-free mandibular first molars, first class inlay cavities were prepared. For each tooth two inlays were manufactured- one by using pressed lithium disilicate (Emax) (n=4) and one by using milled leucite glass-ceramic (n=4). The marginal gap was analyzed circumferentially at the occlusal margin using a table-top Bruker micro CT, by measuring the distance at the occlusal limit of the cavities, between the restoration and the tooth in several points for every surface of each tooth before cementing. Data were analyzed statistically using One �way ANOVA with Tukey�s Multiple Comparison Test performed using 5.00 for Windows (GraphPad Prism 5.00 Software, San Diego, California USA). When the marginal gaps of the inlays made out of different materials on the same tooth were compared, only one result had no statistical significance. The program expressed also results by comparing the gaps of pressed vs milled restorations on different teeth. 11 out of 16 results had statistical significance. Although statistical significance between the two studied materials, we can conclude that both used materials offer a good marginal adaptation within the acceptable limits. By summing up the gathered data we can conclude that the milled ceramic shows a better marginal fit than the pressed ceramic.

In this study were compared two investigation methods, a bi- and tri-dimensional techniques by examining the marginal fit pressed in (BioHPP) Inlays. The study pruved that the BioHPP is a high performance polymer which provides very good clinical results.