Abstract: PURPOSE：To summarize the clinical application of special designed Upcera ST zirconia all-ceramic restorations in cases with limited occlusal space. METHODS：Twenty-one patients with 23-unit restorations were enrolled in this study. First, the shape of abutment teeth and diagnostic wax-up were captured and digitized by Sirona inEos system. Then, each individually shaped framework to grant a defined ST zirconia base core was created by the reduced program of inLab software. Finally, all restorations were veneered with VITA VM9 and evaluated at placement using modified U.S.Public Health Service Criteria 6 to 12 months after restoration. Patients were inquired with satisfaction questionnaire at the same time. RESULTS: During 6 to 12 months of follow-up visit, except for one of 23 restorations was rated as failure by fractured root, none was replaced due to framework fracture or unrestorable delamination of the ceramic veneer. The shape and colour of all restorations were satisfactory. CONCLUSIONS: To ensure optimum long-term clinical results of all-ceramic crown restorations, one important key is to overcome the fragmentation of dental prosthesis through modifying the shape of restoration. Based on the results of this study, the specially designed processing technology shows sufficient stability for ST zirconia all-ceramic restorations within a short term, which is deserved to be used in selected cases.

Key words: CAD/CAM, Super transparent zirconia, All-ceramic restorations