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case report _ implant therapy I Figs. 6 & 7_Presentation at eight weeks. Figs. 8 & 9_Laboratory-made screw-retained porcelain bridge on Straumann synOcta abutments. Figs. 10_The bridge. Figs. 11_Appearance at fit. Figs. 12_Pre-op presentation. Figs. 13_CBCT scan with CEREC integration. oral hygiene was good and she was a non-smoker (gave up 11 years previously). She exhibited bilateral canineguidancewithnoevidenceofanypara-func- tion. Her BPE scores were 312/231. _Treatment options Owing to the patient’s history of periodontal dis- ease and associated mobility, she was aware that someformofreplacementwasnecessary.Thepatient did not want a removable restoration and preferred afixedsolution.Inthisareaofthemouth,eitherfixed bridgework or an implant-retained prosthesis was possible. After discussing the options and highlighting the increased risk of peri-implantitis in patients with previous periodontal disease (Esposito 2006), the patient opted for a fixed implant-retained solution. The treatment was to be planned in such a way that if she lost her posterior molars in the future, a full- archfixedprosthesiscouldbemadeaftersubsequent implant placement. _Treatment plan Treatment was to be carried out as follows: 1.continuation of periodontal treatment and oral hygiene advice; 2.CBCTGALILEOS(Sirona)scantoassessboneheight, bone profile and associated anatomy; 3.extractionofallfourlowerincisorsandtooth#14; 4.placementoftwoSLAactiveimplants(Straumann); 5.restoration with a screw-retained four-unit PFM bridge. _CBCT It was decided to take a full-volume CBCT scan to further assess the upper teeth and tooth #14 for future implant replacement. The CBCT scan showed excessive bone loss around the anterior incisors with a small area of periapical radiolucency around tooth #31. A cross-sectional view showed thick, well-developed cortical plates with very little lingual concavity. Owing to the good bone height and mini- mal pathology, immediate implant placement was planned. Owingtothepatient’sboneloss,thelowerincisors had drifted, giving a less than desirable tooth posi- tion. One of the patient’s main complaints was the gaps that had appeared between the lower incisors and the uneven appearance of the incisal edges. To aid implant placement in the correct angu- lation, a CEREC Bluecam image was taken and ma- nipulated so that the lower tooth positions were in harmony with the rest of the dentition. This proposal was then overlaid onto the CBCT scan and was used to facilitate implant planning. The aim was to provide the patient with a screw- retained bridge with access holes though the lin- gual aspects of the lower incisors, whilst main- taining a sound margin of safety from the lingual cortical plate. I 13CAD/CAM 2_2012 Fig. 11 Fig. 12 Fig. 9 Fig. 10 Fig. 7 Fig. 8 Fig. 13