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I 07 opinion _ implant therapy I CAD/CAM 1_2011 digitallybyusingtheCERECsoftware.Thereafter,the prosthetic planning data is imported into the CBCT scan, eliminating both the need to create an X-ray template and to form a barium-sulphate prosthetic model. This leads to results that are more precise. Moreover,sincenobariumsulphateisused,theCBCT image is of good quality. The positions of the endos- seous drill holes are determined by means of plastic surgery guides (SICAT/Sirona). Minimally invasive flapless implantation eliminates the need for the elevation of the mucoperiosteal flap. This not only minimises surgical trauma, but also permits the im- mediateplacementoftherestorationontheimplant. …and less laboratory work TheabilitytoimporttheCERECdataintotheCBCT imagesignificantlystreamlinestheimplantplanning workflow. The interaction between GALILEOS and CEREC means that only two appointments are re- quired, at an interval of five to seven days. Thanks to the surgery guide, the invasive surgical insertion of theendosseousposttakesonly15minutes,resulting in greater precision and reduced stress. Using the conventional method (that is, without a CBCT scan and surgery guide) each implant requires up to 45 minutes and is accompanied by greater risks. Thus far, custom-made angled abutments with individual emergence profiles have often been re- quired in order to compensate for divergences in the insertion angles between the implants and the superstructures. Thanks to the integrated implant planning process, it is now possible to deploy com- petitively priced, industrially prefabricated abut- ments(Fig.3).Thepreciseplanningoftheangulation in the CBCT image and the guided drilling process ensure a better fit between the endosseous post and the superstructure. If required, specially shaped abutments can be created out of zirconium oxide (ZrO2) using the inLab system. As a rule, the implants are luted directly to single- tooth implants. In order to protect the gingiva, over- pressed luting residues must be carefully removed. Following the attachment of the abutment and the closure of the screw access, it is advisable to place a retraction cord in order to expose the tissue and the abutment margin. The abutment is then conditioned withtitaniumpowderinpreparationforacquiringthe intra-oralimpressionusingtheCERECACanddesign- ing the final implant crown (Fig. 4). The crown is then automatically milled to anatomical dimensions out of a lithium disilicate (LS2) block (IPS e.max CAD, IvoclarVivadent).Thetry-inshouldbeperformedprior to crystallisation. This is followed by crystallisation, polishing/glazing and luting to the abutment (Fig. 5). Ifstringentaestheticrequirementshavetobefulfilled (forexample,intheanteriorregion)theLS2 crowncan be cut back and then individually veneered (Fig. 6). _Conclusion To a significant extent, GALILEOS and CEREC sim- plify implant planning and superstructure fabrica- tion.Theclinicaloutcomesarepredictable.Compared withconventionalmethods,treatmentismuchfaster. The 3-D images and the virtual prosthetic proposal playavaluableroleinpatientcounselling.Inaddition, there is an increased likelihood that the patient will accepttheplausibilityoftheproposedtreatmentand give his or her consent more quickly._ Fig. 4_Screenshot of CAD construction for implant crowns. Fig. 5_LS2 crowns adhesively luted to the abutments. Fig. 6_Implants with supra-structures in situ. Fig. 6Fig. 5 Dr Neal S.Patel operates a dental practice in Powell, Ohio.He is a CEREC user, as well as anAdvancedTrainer for the GALILEOS CBCT system. Dr Jay B.Reznick runs a dental practice inTarzana, California.He specialises in implantology,as well as tooth and skin transplants. CAD/CAM_about the authors Fig. 4