Advancements incomputerized tomography scans (CT and CBCT technologies), coupled withcomputer-assisted treatment planning and a double scan approach, allowed forthe virtual planning of placement of implants in 3D orientation relative to thebone, soft tissue, and final planned prosthesis. In 2002, the concept ofsoftware planning and surgically guided techniques combined with immediateloading was clinically introduced in Leuven, Belgium, by prof. Daniel VanSteenberghe. These early treatments were limited to the edentulous maxilla andrequired a full-thickness flap.
Later, the procedure was refined to allowflapless implant placement through virtual planning, by producing astereolithographic surgical template incorporating metal sleeves to guide theimplant site preparation. Furthermore, 3D planning softwares allow the surgeonto digitally plan on the computer, the position, length, and diameter of every implantto be placed and, at the same time, helps to prevent damage to vitalstructures. Then, the retrofitting of specific implant components (implantreplicas, and guided cylinders with pin) into the stereolithographic surgicaltemplate, an implant-level model, could be produced and a temporary prosthesiscould be fabricated for immediate insertion at implant placement. Severalprospective studies and few RCTs have validated these concept. Currently computer-guided implant protocols are consideredsafe procedures that may help clinicians to perform prosthetic drive implanttherapy often avoiding elevation of large flaps causing less pain anddiscomfort to patients. However deviations in three-dimensional directionsbetween virtual planning and actual final position of the implant in thepatient’s jaws, and technique-related peri-operativecomplications have to be taken into account. Although, favorable clinicalresults of computer-assisted template-guided surgery have been shown in severalstudies, only one randomized clinical trials (RCTs) has been publishedcomparing the use of computer-guided surgery with conventional treatment,reporting no statistically significant differences in term of implant andprosthetic survival and success rates between computer-guided and free-handrehabilitations, but less patient discomfort in the guided surgery group. Described in 1998, the double-scanning workflow andthe 3D representation of the CT or CBCT images with alayered prosthetic plan, represented a major breakthrough for digital implantplanning and preoperative patient assessment.
Panoramicradiography and intraoral radiography are still the basic imaging methods indentomaxillofacial radiology, a comparative study of Wolff et al. (2016) proved thatthere is a better concordance in oral and maxillofacial surgery outcome whenplanning with 3D images versus 2D images. The European Association for Osseointegration (EAO)and The International Congress of Oral Implantologists (ICOI) have publishedtheir recommendations quite recently. Double scan protocol is based on two separate sets ofDICOM files. It can be used for both partial and complete edentulous patients.The first CBCT scan will be of the patient wearing the radiographic guide withthe radiopaque markers.
The second scan will be of the patient’s radiographicguide alone. Based on the spherical markers visible in both scans,the scans are superimposed onto each other, resulting in a 3D bone model of thepatient together with a 3D model of the radiographic guide. The combination of a 3D bone model and 3D radiologicaldataset lets dental professionals to evaluate bone quantity, underlyinganatomical structures such as nerves and blood vessels, as well as dentalroots, can be identified and marked with the help of several reslice views.Special tools are available to highlight dental roots, nerves and otheranatomical structures or restrictions. Software allows to turn 3D images,rotate these images, and to view the treatment plan from all angles simplifyingdiagnostic procedures and placement of implants.
3D distances can easily bemeasured, and a tool to measure the grey values is also available. Theseanatomical annotations are visible in the 3D setting and in the reslice viewer. The combinationof a 3D bone model, including the 3D radiological dataset and the 3Dradiographic guide model, enables clinician to place implant locationsaccording to anatomical, functional and esthetics needs and demands based on theprosthetic setup. In order to achieve this, the clinician virtuallypositions the implants, with the optimal length and diameter. Any of themodifications in 3D location and implant type, size or shape can be done in the3D setting or in the reslice viewer. After finalizing the planning, thecorresponding surgical template is designed. The surgical template thusfabricated contains all the necessary planning information-It is customizedaccording to location, type and size of the planned implants (Figures from case1). In the treatment of partially edentulous patient, it ispossible to save time by skipping the radiographic guide, also avoidingadditional patient visit.
This is possible thought the introduction of a noveldigital integrated workflow that combines the DICOM data belonging to the CBCTexamination of the patient with the STL data derived from the optical digitalhigh-resolution scan of the preoperative patient master cast and tooth setup,or by digital intraoral impression. The STL data are integrated with the craniofacialmodel to create a more accurate 3D model of the teeth. It is thus possible tovisualize hard and soft tissue anatomy and to obtain a more precisesegmentation of the residual dentition. This process is named Smart Fusion, and it represents the ability ofNobelClinican to combine the CBCT patient scan with the NobelProcera scan ofthe model & wax-up into a single surgical and esthetic view. Thisprotocol greatly simplifies the overall treatment workflow by eliminating theneed for two CT scans while providing an enhanced fit of the Surgical Guide tothe patient (Figures from case 2).
The prosthetic-driven planning workflow will start withtaking a cone beam computed topography scan of patient, by using a wax bite toseparate dental arches. The next step is to create a digital model, which canbe accomplished in two ways: the clinician can use an intraoral scanner tocreate a digital models (fully digital workflow); or the clinician can take atraditional impression and then scan the impression (reverse engineering) orthe poured master model, by using an extraoral scanner (conventional workflow).It is highly recommend to take a definitive impression with the maximumextension and details, by using vinyl polysiloxane or polyether materials, andthen poured the impression with a low expansion, class IV gypsum (usable with aextraoral scanner). This is because the surgical template derives directly fromthe master model. Afterwards, an occlusal registration can be made with hardwax or resin.
In the fully digital workflow, the digital STL data will beimported in a 3D design software to realize a virtual wax-up according to theesthetic and functional requirements. In the conventional workflow, a vinylpolysiloxane or polyether impression will be taken with a customized tray. Theimpression will be poured with Gypsum IV Class and then, the models will bemounted in a fully adjustable articulator. Afterwards, a dental wax-up will bemade accordingly to the functional and esthetic requirements. Finally, mastercast and wax-up will be digitalized by using a lab scanner. Irrespective of the workflow used to digitalize the anatomyinformation, the data from dental and gingival, acquired by intraoral orextraoral scanning (STL data), and the bone informations, radiographicallyacquired by a CBCT scan (DICOM, Digital Imaging and COmmunications inMedicine), will be imported in a 3D software planning program. Then, thereprocessed surface extrapolated from the DICOM data (by using a Hounsfieldscale filter) and the surface generated by the master cast scanning process orby the intraoral scanning process, are merged based on the matching betweennumerous points on the surface of patient’s dental castsand the corresponding anatomical surface points in the CBCT data.
Introduced in 2011, NobelClinician builds on itspredecessor, the NobelGuide treatment planning software, which was the firstvirtual planning system based on the double-scan technique. In NobelClinician,the clinician views the 3D data set derived from (CB)CT scan data that consistof a series of transaxial images, orthogonally aligned to the patient’svertical axis and registered as one volume. By selecting slices in any plane,data integrity is always fully preserved, as no recalculation is involved.
Scandata are stored and distributed in the standard DICOM (Digital Imaging andCommunications in Medicine) format and can be easily analyzed and shared. At this point,prosthetic-driven implants/abutments size and location can be planned takinginto account the bone quality/quantity, soft tissue thickness, anatomicallandmarks, as well as, the type, volume and shape of the final restoration. Before surgery, the NobelClinician Communicator app(lication) helps dentalprofessionals (surgeons or surgical specialists as well as generalpractitioners placing implants) to present chairside patient plans and imagesexported from NobelClinician via NobelConnect, and to communicateeffectively all the diagnostic findings and discuss and explain theproposed implant treatment plan to the patient. The application works withNobelClinician Software, and it is designed for iPad®.
The software alsoallows to show clinical images, photographs, screenshots andx-ray images, as well as, to select “educationalimages” to explain different treatment options. Finally, drawing on images andplannings to emphasize important topics is also allowed. In March 2017 Nobel Biocare will also launched a newtime-saving CAD/CAM-based protocol that enables clinicians to receive a screw-retainedTempShell provisional restoration from a dental laboratory in time forplacement on the day of implant surgery. The SmartSetupsoftware dramatically reduces the time it takes clinicians tocreate a prosthetic-driven treatment plan. This plan can then be used by thedental laboratory for the fully digital design of the cement-free TempShellprovisional restoration. Incorporating several of Nobel Biocare’s leadingdigital technologies, the updated workflow has been developed not only toshorten time-to-teeth, but to increase both treatment efficiency and acceptanceas well as further improve collaboration between dental professionals. The 2018 will not be less. The new DTXStudio diagnostic software, will serve as a digital hub connecting the latestNobel Biocare and KaVo solutions for patient data digitization, diagnosis,planning, surgery and restoration, from beginning to end.
DTX Studio isalso set to offer easy access to industry-leading implants and restorativeoptions. By providing true, seamless links between every aspect of a dentalprofessional’s daily work, this smart solution aims to set a new standard intreatment efficiency and patient care. The software easily connects any imagingdevices in dental practice, whether using 2D or 3D, introra or extraoraltechnologies, allowing to view them directly in DTX studio software. Thesoftware consists of different modules, with multiple work spaces, which can beflexible selected according to the clinicians’ needs.
The software can be simpleconnected with other digital devices to easily produce surgical templates,models and provisionals by using a 3D printing and in-lab milling, but alsoproduction of prosthetic frameworks, full-contour restorations or surgicaltemplate at one of our centralized production centers. In fact, users,connecting to 3D printers, can be able to export STL files for local productionof surgical template, temporary eggshell provisionals (Tempshell) and models.Connecting to in-lab production, users can be export files for local productionof tooth-based restorations, provisionals and models. Otherwise, Individualizedsurgical templates and CAD/CAM prosthetics restorations (single- andmultiple-unit implant-based restorations, tooth—based restorations, and implantbars for major implant platform, can be sent for industrial production with aturnaround time of just a few days at external production facilities (millingcenter) in USA or Japan.