Nobel Biocare

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Dr Renaud Noharet

Wed. 3. January 2024

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An 82-year-old patient presented for complete rehabilitation. The existing maxillary bridge showed Grade III mobility and the residual mandibular teeth between Grade II and Grade III mobility. The patient did not present with any general pathology, and her only complaint was difficulty while chewing.

Clinical evaluation showed a lack of dental support for the lower lip and significant gingival recession around the maxillary bridge and the three residual mandibular teeth (Figs. 1 & 2). After clinical and radiographic examination (Figs. 3 & 4), the decision to perform a full-mouth fixed rehabilitation with implants was made in agreement with the patient.

Fig. 1: Initial situation. Patient’s face showing a visible lack of dental support for the lower lip. (All images: Renaud Noharet)

Fig. 2: Intra-oral view of the maxillary bridge, the significant recession and the three residual mandibular teeth.

Fig. 3: Dental panoramic tomogram of the clinical situation.

Figs. 4a–c: Combination of the various essential files to collect all the data necessary for the diagnosis, treatment plan and proper execution of the plan. CBCT (DICOM; a). Intra-oral scan (STL; b). Intra-oral photograph (JPEG/MPEG; c).

The combination of DICOM and STL data in the context of full or partial edentulism is complicated by the lack of reliable fixed reference points. The solution is to place stickers with radiopaque beads. These beads can be identified both radiographically by their opacity and on the optical impression by their volume. This facilitates the combination of the data (Fig. 5). During the planning of implant treatment, DTX Studio Implant software was used (Fig. 6). It was decided to place four implants.

Fig. 5: Intra-oral view of the mandible showing the partial edentulism and stickers with radiopaque beads.

Figs. 6a & b: Implant planning with DTX Studio Implant (a). The vestibular-lingual view highlights the benefits of the radiopaque beads on the stickers for the good combination of DICOM and STL data (b).

The prosthetic design (previously validated in the mouth) can also be digitised in an STP file, and therefore, it can be combined with the STL file of the initial situation. This makes it possible to show the prosthetic design on the bone data, making the planning more functional and biological. At the same time, it is possible to transform this prosthetic plan into a provisional prosthesis (DTX Studio Lab) adapted to the planning (perforation of the prosthesis adjacent to the position of the future implants and abutments). This prosthesis had four rods at the level of the intrados for insertion into the bone. After drilling with dynamic navigation (X-Guide, X-Nav Technologies), they enable the prosthesis to be positioned correctly (Fig. 7). The provisional prosthesis was prepared from PMMA and made up with pink composite resin to simulate the gingiva (Fig. 8).

Navigated implant surgery was performed. The patient tracker was fixed to the bone, and the calibration was done by tracking bone points with a specific probe (X-Mark protocol; Fig. 9).

It had been decided to use N1 implants (Nobel Biocare; Fig. 10). The prosthetic abutments were placed and tightened to the recommended torque, and the temporary titanium abutments were screwed on to the prosthetic abutments (Fig. 11).

Fig. 7: Design of the prosthesis.

Fig. 8: Provisional prosthesis of PMMA and pink composite resin.

Fig. 9: Navigated implant surgery (EDX patient tracker arm attached).

Fig. 10: Occlusal view of placed implants.

Fig. 11: The temporary titanium abutments screwed on to the prosthetic abutments.

Afterwards, the provisional prosthesis was placed on the temporary abutments and positioned precisely thanks to the rods, which were received by the intraosseous lodgement created during navigation, thus ensuring their precise positioning. Flowable composite was then injected to attach the temporary abutments and the provisional prosthesis (Fig. 12). After the injected composite was polished, the provisional prosthesis was screwed on (Fig. 13). A radiograph performed after placement of the provisional prosthesis showed good integration of the implants (Fig. 14).

Fig. 12: The provisional prosthesis placed on the temporary abutments.

Fig. 13: The provisional prosthesis in situ.

Fig. 14: Radiograph control after placement of the provisional prosthesis.

Overview of the digital solutions used in the presented case

DTX Studio Implant (formerly NobelClinician) supports the image-based diagnostic process and treatment planning. It offers a visualisation technique for CBCT images of the patient. In addition, 2D image data such as photographic images, radiographic images and surface scans may be visualised to bring diagnostic image data together. Prosthetic information can be added and visualised to support prosthetic implant planning. For a guided surgery plan, the software can be used for a variety of integrated options: static pilot guides, fully guided surgery or dynamic navigation. The surgical plan, including the implant positions and the prosthetic information, can be exported for the design of dental restorations in DTX Studio Lab.

DTX Studio Lab integrates CAD software to render the digital design of a dental restoration. The resulting output file of the design can be used for either centralised or localised manufacturing.

X-Guide is a dynamic navigation system for 3D real-time guidance of drill positioning with no surgical guide. It is designed to improve the precision and accuracy of the position, angle and depth of the implant. Reference points are tracked and displayed in real time via two cameras that are positioned 60–80 cm above the patient. The display guides the surgeon in drilling in the location according to the DTX Studio Implant plan. Virtual registration of the patient’s anatomy can be done with the X-Mark protocol, meaning no CBCT marker is required for the scan. Three points are marked on the CBCT rendering in X-Guide, and the same three points are marked in the patient’s mouth with a probe tool. For edentulous cases, the EDX patient tracker arm is attached to the patient and clears the lip and does not interfere during surgery. It is suitable for both flapped and flapless surgery, and different arm designs are available based on the surgeon’s handedness.

Studies have confirmed better accuracy and less deviation from the planned implant positioning, compared with freehand surgery.^{1, 2}Compared with other tested dynamic systems, X-Guide is three to four times more accurate.³

The N1 implant system is suitable for all indications in all bone types and for immediate function and fully digital workflows. It enables productivity and predictability through a faster surgical protocol, including site preparation that is less traumatic.

Editorial note:

This article was published in digital—international magazine of digital dentistry vol. 4, issue 3/2023.

References

Block MS, Emery RW, Lank K, Ryan J. Implant placement accuracy using dynamic navigation. Int J Oral Maxillofac Implants. 2017 Jan–Feb;32(1):92–9. doi: 10.11607/jomi.5004.
Block MS, Emery RW, Cullum DR, Sheikh A. Implant placement is more accurate using dynamic navigation. J Oral Maxillofac Surg. 2017 Jul;75(7):1377–86. doi: 10.1016/j.joms.2017.02.026.
Emery RW, Merritt SA, Lank K, Gibbs JD. Accuracy of dynamic navigation for dental implant placement—model-based evaluation. J Oral Implantol. 2016 Oct;42(5):399–405. doi: 10.1563/aaid-joi-D-16-00025.