2^nd International Conference and Expo on Dentistry & Prosthodontics May 01-02, 2017 Toronto, Canada

Farshad Dehnavi is a Dental Student of Shahid Beheshti University of Medical Sciences. He has been a participant in the Animal Study Workshop in Tehran University of Medical Sciences in 2014. He had given oral presentations in student panel of 16th International Congress of Iranian Association of Prosthodontists in 2016, the Second Scientific Dental Students Tournament and the 15th Congress of Iranian Academy of Periodontology in 2015. He has presented in poster presentation of the 56th EXCIDA Congress in Conjunction with the 1st FDI Persian Regional and the 34th ICOI World Congress in May 2016. He has worked for one year in Talented Office of University of Medical Sciences in 2013. He has been a Teaching Proposal Writer in Shahid Beheshti University of Medical Sciences. He is also a member of Talented Office of University of Medical Sciences annually. rnrn

The demand for tooth-colored restoration has grown considerably during the last decade. The restoration of anterior teeth is a difficult task, even for an experienced operator. Color is the most important determinant of esthetics. The esthetic appearance of a restoration should match the surrounding dental tissue. This requires that the optical properties of the restorative material be similar to that of the natural teeth. Thus, for an acceptable esthetic result, favorable shade matching of the all-ceramic restoration should be achieved by controlling absorption, reflection and transmission of dental ceramic material. Currently there are many different ceramic systems that can be used to achieve highly esthetic results. These include metal-ceramics with porcelain margins, In-Ceram, Hi-Ceram, IPS-Empress, Optec, and CAD/CAM ceramics. All ceramic systems have different composition, microstructure, crystalline content and phases. Direct transmittance, translucency, opacity and opalescence, all influence the optical properties of the ceramic restoration. Other factors include the thickness of ceramic, number of firing, glazing, powder/liquid ratio, surface texture and even the resin shade. This article focuses on controlling these variables to achieve the best possible esthetic result with an all ceramic system with the emphasis on CAD CAM systems.

Mohammad Ebrahim Ahmadnejad is an Assistant Professor in Prosthodontics department of Babol Dental University. He received a Doctor of Dental Surgeon from Islamic Azad Dental University. He worked for 2 years as a General Dentist in Boshehr city of Iran. He finished his Post-graduate study in 2016

Introduction: Spark erosion technology is a highly advanced system for producing the ultimate in precision fit of the prostheses frameworks. In this process metal is altered in a form using short-circuit impulses created within a dielectric medium similar to light oil. This process became more popular in the early 1940s in the tool and die industry. Since then, the dental profession has adapted its uses for fabricating precision-removable partial dentures, titanium crowns, and implant-retained over dentures.rnrnMethods & Materials: In removable partial dentures, this technology uses a tool system that permits repositioning of the casting with great accuracy and an electric discharge machine that is programmed to erode minute metal particles through periodic spark intervals. In implant dentistry, achieving a passive fit between the implants with the infrastructure and the superstructure is imperative for long-term osseointegration. Mechanical failures from a non-passive fit may cause mechanical failures of the implants and/or the prosthesis or may adversely affect the surrounding gingiva. rnrnResult & Conclusion: Using spark erosion technique, the resultant prostheses were retentive and provided a number of benefits offered by both conventional overdenture and fixed prosthetic designs. This article explains why the spark erosion machining has a significant impact on today\\\'s dentistry.