| Objectives By the study to the edge microleakage and the interfacial integrity of thefixed mental prosthetic made of Ti which are made by different manufacture technologyand bonded by different cements by the means of dyeing and electric mirror and initiallystudy. Hope it will give a guide to the design of the prosthetic and the election of thecements.Methods30healthy human premolars which were pulled out of the mandible because ofthe need of orthodontic were randomly divided into2groups, which contained15premolars. These elected premolars were preserved in0.9%saline at room temperatureafter being cleaned the things attaching to the surface of the teeth. Prepare the teeth as thedemand of the normal mental prosthetic crowns, make the edge of preparation being theform of chamfer and polish them to guarantee smooth. Take the models of the preparedteeth by silicon rubber and send the models to the factory which makes the mentalprosthetic crowns made of Ti. All the prosthesis were made by the same mechanic in thesame mechanic of the factory. Take two manufacturing technology, one called castingtechnology; the other one called computer aided design and computer aidedmanufacture(CAD/CAM). There are15crowns. Every group would use glass ionomer CX,resin-modified glass ionomer Rely X Luting and resin cements Rely X Unicem as lutingagents and each with5human premolars every group. After luted, the teeth would go onthe experiment called dyeing by a kind of colourant called methylthionine chloride. Collectthe acquisition of mental crown restoration made of Ti microleakage staining sectiondigital image with Olympus Stereomicroscope and observe the penetration and rate thedata that we got from the observation according to the rating criteria. After we get the data,observe the section of the mental crown restorations made of Ti sectional with electronmicroscopy. Observe the distances of the prosthesis edge to the preparatory body shoulderin the electron after they were sprayed and vacuumed and at the same time observe theedge suitability of these mental crown restorations made of Ti and the preparatory body bydifferent production process.Results1In the experiments with the same cements, the mental crown restorationsmade of Ti made by the CAD/CAM technology were better than by the casting technology in the edge suitability, and there are statistical significant (P<0.05).2Withthe same manufacturing technology, there are no statistical significant in the edgesuitability to the mental crown restorations made of Ti with the different cements(P<0.05).3With the same manufacturing technology, Rely X Unicem resin cements arebetter than resin-modified glass ionomer Rely X Luting which is better than glassionomer CX in the edge sealing function of the cements to the mental crown restorationsmade o Ti(P<0.05).4In the experiments with the same cements, the mental crownrestorations made of Ti made by the CAD/CAM technology were better than by thecasting technology in the edge sealing function of the cements, and there are statisticalsignificant (P<0.05).5Observed by the electric microscope, there are fissure and bubblein glass ionomer CX, resin-modified glass ionomer Rely X Luting and resin cementsRely X Unicem.Conclusions1In the condition of this experiment, the restorations with the differentmanufacture have the different edge fit. Above all, the restorations made by CAD/CAMare totally better than those made by casting technology and they have the lessmicroleakage.2In the condition of this experiment, the restorations with the differentcements have the different edge microleakage though they are made by the samemanufacture technology. In the experiment, these cements have the different sealingeffect. The best is resin cements Rely X Unicem. The better ones are resin-modified glassionomer Rely X Luting which is better than glass ionomer CX.3Resin cements Rely XUnicem are fairly ideal luting cements to the mental restorations made of Ti, because oftheir lower microleakage. |
PDF Full Text Request