cone beam international magazine of cone beam dentistry

12 I I special _ evolution of dental implantology understanding of the relationship between the tooth and the underlying bone. The ideal pre-surgical workflow should require conventionalimpressionsandmountedarticulated studycasts.Adiagnosticwax-up,orduplicateofthe patient’sdenturerepresentingthedesiredtoothpo- sition can then be utilized to fabricate a radiopaque scanningappliancetobewornbythepatientduring the scan acquisition. Depending on the interactive treatment planning software, protocols can differ requiring fiducial markers that act to register the digitalinformationtotheCBCTscandata.Addition- ally, the proliferation of optical scanning devices atdentallaboratories,orintra-oralopticalscanners can play a role in acquiring this digital information that will be merged with the data from the CBCT scan enhancing the accuracy of the planning soft- ware (Figs. 2a & b). Utilization of a scanning appli- ance provides the clinician an unparalleled ability to visualize the relationship between the tooth and theunderlyingbone.Usinganinteractivetreatment planning software such as SimPlant (Materialise Dental), NobelClinician (Nobel Biocare), Treatment Studio/Invivo5 (Anatomage), BlueSkyBio (Blue Sky Bio) the virtual implant can then be positioned within the receptor site to fit within the envelope of the desired restoration. However, it needs to be noted that the link between the implant and the tooth is the abutment. Therefore it is essential to place a virtual abutment or an abutment “projection” with an appropriate vertical height to visualize the spatial positioning of the abutment as it relates to the tooth to achieve restoratively driven outcomes (Figs. 3a & b). _Utilizing the data The utilization of CBCT imaging and interactive treatment planning has been increasing in its adoption for planning both the surgical and prosthetic phases of treatment. Once the scan in taken regardless of whether a scanning appliance is used, the clinician has several options in utilizing data: _diagnostic-freehand; _template-assisted; _and full template guidance. Each CBCT device has it’s own native software which can provide valuable three-dimensional information about the patient’s anatomical pres- entation. The concept of diagnostic-freehand can be divided into two applications: _the surgeon can visualize this data, make meas- urements, plan the implant positions, communi- cate with the restorative dentist and then per- form the surgical placement free-hand based on his/her personal level of experience; _or the CBCT data (DICOM—digital communica- tion in medicine) can be imported into an inter- active treatment planning software where there are additional diagnostic and implant planning tools to enhance the process (Fig. 4). The surgeon can then perform the surgery free hand based upon the information gleaned from the virtual plan. Template-assisted protocol can be described where the information from the interactive treat- ment planning software can be utilized to fabricate a surgical guide. Surgical guides come in several typesincludingboneborne,toothborne,orsofttis- sue/mucosalborneandcontainguidecylindersthat correspond to the drilling sequence for osteotomy creation (Fig. 5). Surgical guides can be used in flapless/minimallyinvasive,orflappedsurgicalpro- cedures helping to increase accuracy, minimize surgical time, and potential patient morbidity. Full template guidance encompasses perhaps the most important innovation where there is a link between the surgical guide and the implant manufacturers’ components. The development of implant specific hardware allows for full template guidance—when it is possible to deliver the im- plants through the guide with specially designed carriers that provide for the most precise place- Fig. 4_Precise measurements of available bone can be made in the cross-sectional view. Fig. 5_A tooth borne surgical guide containing guide cylinders for accurate drilling. Fig. 6_Full template guidance allows for the implant to be delivered through the guide with specially designed carriers. cone beam1_2014 Fig. 4 Fig. 5 Fig. 6 CBE0114_10-14_Ganz 31.01.14 15:50 Seite 2