Citation ABSTRACTFixed prosthodontic failures are varied and complex. Complications associated with conventional fixed prostheses are dental caries, need for endodontic treatment, periodontal disease. Poor esthetic is one of the most frequent reasons for replacing failed restorations. Knowledge regarding the clinical complications enhances clinicians to complete a thorough clinical examination and diagnosis, and to develop an esthetic-driven treatment plan including the selection of bleaching agent, the reconstruction type, and the ceramic material. This article illustrates several clinical complications of full coverage restorations, and discusses different therapeutic modalities which have to be combined and synchronized to enhance the esthetic outcome of the final fixed prostheses.

One of the basic principles of tooth preparation for fixed prosthodontics is conservation of tooth structure. This is the major advantage of bonded bridge as an alternative to implant retained restorations in the esthetic zone. Especially used for juvenile patient who do not come into consideration for implant therapy?. This article describes the use of an all ceramic resin-bonded bridge as a conservative and esthetic solution for the replacement of 2 mandibular incisors for a 17-year female patient.

This case report highlights an esthetic replacement of defective metal ceramic bridge by a ceramic zirconia one after performing the necessary changes in preparations to ensure esthetic and function.

The successful use of zirconia ceramics for the fabrication of tooth-supported restorations has encouraged clinicians to extend its application for implant-supported restorations. CAD/CAM technology in combination with zirconia ceramic has increasingly gained popularity in implant dentistry [1]. Zirconia implants were introduced into dental implantology as an alternative to titanium implants. Zirconia seems to be a suitable implant material because of its opacity, mechanical properties, biocompatibility, and low plaque affinity.Apical bone loss and gingival recession associated with implants often uncover portions of the metal implant, revealing a bluish discoloration of the overlying gingiva. The use of zirconia implants avoids this complication and accedes to the request of many patients for metal-free implants. The inflammatory response and bone resorption induced by ceramic particles are less than those induced by titanium particles, suggesting the biocompatibility of ceramics [2].Today, the majority of implant manufacturers offer zirconia abutments for aesthetic implant-supported restorations. Abutments are available in prefabricated or customized forms and can be prepared in the dental laboratory either by the technician or by utilizing CAD/ CAM techniques. The biocompatibility of zirconia toward soft connective and epithelial tissue is essential [1]. Moreover, Y-TZP abutments may promote soft tissue integration, while favorable peri-implant soft tissues may be clinically achieved adjacent to zirconia abutments and zirconia healing caps. Besides strength considerations, Y-TZP implant abutments offer metal-like radiopacity for better radiographic evaluation, and, ultimately, reduced bacterial adhesion, plaque accumulation and inflammation risk. A systematic review revealed that zirconia abutments could maintain an equivalent bone level in comparison to titanium, gold and aluminum oxide ones [3]. In a randomized controlled trial, 20 customized non HIPed-based zirconia single-tooth implant abutments and 20 customized titanium singletooth implant abutments were followed for 3 years, with no fractures or loosening of abutments in both group and a 100% survival rate reported [4].

After many years of cementation of a conventional bridge, it is possible that patients may present with fractured abutments teeth due to many reasons including recurrent caries, trauma and debonding composite. In this study an original technique for retrofitting an old bridge using duralay resin as models to perform two casted posts and cores by a direct technique with which the additional time and cost of preparing a new bridge can be avoided.