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28 I I case report _ customised implant abutments composite. An adjustment check of the contact points and of the occlusion was performed, fol- lowed by cementation of a ceramic bridge with a zirconia framework. A follow-up visit took place three days later. Technique For this case, it was possible to use abutments made from different materials according to the angulation of the implant: titanium for the pro- nounced angulations, and a combination of ti- tanium and zirconia for the angulation with no particular constraints. It would have been equally possible to use a titanium abutment for the im- plant in region 23 but I opted for the titanium– zirconia abutment to obtain a better aesthetic result in the anterior region: brightness, translu- cency and no visible metal margin. Customised CAD/CAM prosthetic elements and abutments respect the dental anatomy and allow extremely precise seating of a bridge on implants. Periodontalmaintenanceisthereforeeasierowing to easy access with a toothbrush because of the predetermined interdental spaces. The simplicity of the process saves a consider- able amount of time: no adjustments are neces- sary, the bridge is seated immediately, the occlu- sion is usually ideal, and greater accuracy can be achieved. In addition, only two appointments are necessary: one for impression taking and another for seating of the bridge. _Dental technician’s perspective When the laboratory (Laboratoire Dentaire Crown Ceram) received this case, we were asked to create three customised anatomical abutments with a titanium interface for an individual and more precise fit, respecting the require- ments of biocompatibility and biome- chanics, and a coronary part in zirconia for a better aesthetic result. Once the moulds had been cast, we determined that the considerable an- gulation of the implants in regions 24 and 25 and their shallow position in the tissue posed difficulties regarding the design of titanium–zirconia abutments. However, Dr Lachkar explained to us that in this case (i.e. the patient’s reluc- tance to undergo pre-implant surgery) he was forced to place the implants in the bone available and not necessarily in the ideal situation according to a prosthetic plan. In this case, the titanium interface would have considerably exceeded the buccal surface and it would therefore have been necessary to reduce it. The bonding surface would therefore have been limited, which would have resulted in a great loss of mechanical resistance. We thus decided to use a titanium abut- ment manufactured from a single block and spe- cially made to allow for such substantial angula- tions for teeth 24 and 25. For tooth 23, the implant angle allowed for a titanium–zirconia abutment, which was preferred to a titanium abutment for a better aesthetic result._ Figs. 7 & 8_The abutments in situ. Note the slight blanching of the gingival mucous membrane, indicating good subgingival adaptation. Figs. 9 & 10_Final result. CAD/CAM 2_2013 Fig. 7 Fig. 9 Dr Thierry Lachkar is a dental surgeon (Paris Diderot University) and has been a practitioner for 15 years.He is a general practitioner and he works at a dental surgery in Paris. He has specialist postgraduate training in conservative dentistry and in endodontics. He can be contacted at drlachkar@yahoo.fr. CAD/CAM_about the author Fig. 8 Fig. 10