Virtual Treatment Planning for Success

Ara Nazarian, DDS

0 Shares

These days, more and more patients are presenting to the dental practice with a myriad of dental issues that require a thorough clinical examination protocol. This includes the utilization of 3-D CB x-rays, virtual implant treatment planning, and CT-based surgical guides so that the dental provider may diagnose the patient and then do any needed surgery with greater precision. An accurate diagnosis, ideal treatment planning, and precise surgical technique can all be efficiently accomplished using CT-based computer generated diagnosis and treatment.

CASE REPORT
Diagnosis

A patient in her late 50s, referred to us by her general practitioner (GP), presented to the office for an initial consultation with discomfort due to cervical caries and generalized advanced periodontal disease (Figures 1 and 2). Additionally, she complained of mobile teeth and a bad odor coming from her mouth. The referring GP had requested that I do both the surgical and restorative work for this patient.

Initial diagnostic evaluation at the consultation consisted of a series of digital images with study casts, a bite registration, and a full-mouth series of radiographs. The patient had existing metal mesh with composite bonded to the lingual surfaces of her maxillary anterior teeth (Nos. 6 to 11) and her lower mandibular anterior teeth (Nos. 22 to 27). These had been placed many years previously to splint and stabilize her dentition due to the mobility from periodontal disease. Deep cervical caries were also present in her posterior maxillary and mandibular teeth. After periodontal probing and a review of her full-mouth radiographs, it was apparent the patient suffered from severe generalized periodontal disease. Having already visited multiple providers in the past for periodontal therapy and surgery, she was very frustrated with the prognosis of the varying results. Because of this, she was now ready for a more comprehensive approach that would enhance her dentition, from both a structural and aesthetic standpoint, for a longer duration.

Before any surgical appointment, a CBCT (i-CAT) scan was taken to accurately treatment plan this case to make certain that no complications would arise from doing extractions, leveling, grafting, implant placement, and provisionalization within one appointment (Figure 3).

Figure 1. Preoperative facial view. Figure 2. Preoperative 1:2 retracted view.
Figure 3. Custom 3-D conversion by 3DDX (3D Diagnostix). Figure 4. Maxillary virtual treatment
superimposed.
Figure 5. Maxillary virtual treatment with implants. Figure 6. Mandibular virtual treatment superimposed.
Figure 7. Mandibular virtual treatment with implants. Figure 8. Physics Forceps (Golden Dental Solutions).

SimPlant software (Materialise Dental) was used through 3D Diagnostix virtual assistance to precisely plan the placement of 4 ET III SA (HIOSSEN) dental implants in the maxillary arch (Figures 4 and 5) as well as 7 ET III SA implants in the mandibular arch (Figures 6 and 7) using CT-based surgical guides. The final treatment plan chosen consisted of a metal-reinforced overdenture secured by implants and LOCATORs (ZEST Anchors) in the upper arch, and a fixed bridge on implants in the lower arch.

Treatment Planning
To develop a treatment plan, diagnostic models were forwarded to the dental lab team to be mounted on an articulator for further analysis. This was done as a part of working optimally to meet our patient’s aesthetic and functional needs. Instructions for a diagnostic wax-up were prescribed for increasing the patient’s vertical dimension of occlusion due to a collapse in her bite (a complication resulting from her advanced periodontal disease).

As a result of the information gathered from the diagnostic wax-up, it was determined that aesthetics and function would be enhanced by restoring the entire maxillary and mandibular arches with implant-supported restorations. Once all risks, benefits, and alternatives of the various treatment options were reviewed with the patient and a financial plan was discussed, it was decided that the final treatment plan would consist of full-mouth edentulation followed by implant placement and restoration. In the upper arch, the metal-reinforced, palate-free denture would be supported by 4 dental implants, and in the lower arch, fixed bridges would be supported by 7 implants.

The CT/CBCT allows clinicians to visualize a variety of different views and cross sections of the hard tissue, in addition to any anatomical landmarks including sinus cavities, bone concavities, and nerve canals. Using this information, there is no guesswork in deciding where the optimal position is for ideal implant placement.1 These images were imported into the proprietary software (SimPlant) through 3D Diagnostix, creating a customized conversion which allows the dental provider to visualize the patient’s anatomy in a colorful high definition image with 360° rotation. Variations and aberrations of normal anatomy were easily visualized. From this point, with the assistance of 3D Diagnostix, we virtually planned treatment for the placement of implants according to this individual’s anatomy and case plan. The type and size of the planned implant, its position within the bone, its relationship to the planned restoration, and its proximity to vital structures were determined before performing the surgery. Then, once approved, surgical drilling guides were fabricated from the virtual treatment plan with pinpoint accuracy, so that each implant would be placed exactly where and how it was intended to be. In this particular case, bone level surgical guides were fabricated with 2 anchor pins for stability.

Figure 9. Maxillary CT-based surgical guide. Figure 10. AEU7-000 surgical motor (Aseptico).
Figure 11. ET III SA (HIOSSEN) implant. Figure 12. Premounted implants placed in maxilla.
Figure 13. Mandibular CT-based surgical guide. Figure 14. Premounted implants placed in mandible.
Figure 15. Temporary PEEK abutments. Figure 16. Panoramic (PANOREX) radiograph of implants placed.

Clinical Protocol
When I am performing full-mouth extractions in one visit, I will utilize intravenous sedation to make the procedure more efficient and comfortable for the patient. Since the patient is sedated, a mouth prop (LogiBloc [Common Sense Dental Products]) is used to keep the mouth open. LogiBloc’s unique design stabilizes and comfortably supports the jaw while allowing the dental provider unrestricted visual and physical access to the working area.

Once the patient was completely sedated and anesthetized, the teeth were extracted in a systematic manner working in sections at a time starting from the anterior maxillary teeth. Acting like a modified Class I lever, the Physics Forceps (Golden Dental Solutions) was used to atraumatically extract the teeth with the goal of trying not to disturb the underlying bone (Figure 8). The beak of the forceps was placed on the lingual cervical portion of each tooth, where the soft bumper portion was placed on the buccal alveolar ridge at the approximate location of the muco-gingival junction. During the extraction process, the beak grasps the tooth and the bumper acts as the fulcrum. Extractions were accomplished with only slight wrist action in a buccal direction taking about 40 to 60 seconds each, depending on the tooth morphology and density of bone. Once all the maxillary teeth were extracted, the alveolar crest was leveled 2 to 3 mm apically with the AEU-7000 surgical motor/handpiece (Aseptico), so that the patient’s maxilla would not be visible in the aesthetic zone and there would be sufficient thickness for the denture prosthesis.

Figure 17. Smart Peg (Osstell) inserted for reading. Figure 18. Implant Stability Quotient reading on Osstell unit.
Figure 19. The tray was loaded with a vinyl polysiloxane impression material (Take 1 Advanced [Kerr]). Figure 20. Denture teeth were selected.
Figure 21. Facial view of lower fixed partial denture (FPD). Figure 22. Occlusal view of lower FPD.
Figure 23. Occlusal view of upper overdenture. Figure 24. Panoramic radiograph of completed treatment.
Figure 25. Postoperative full-face photo of the happy and now self-confident patient.

A bone-level, CT-based pilot surgical guide provided by 3D Diagnostix was inserted and stabilized with 2 retention pins to the maxillary arch (Figure 9). Using the Mont Blanc surgical handpiece and Aseptico surgical motor (AEU 7000) at a speed of 1,400 rpm with copious amounts of chilled sterile saline (Figure 10), the sites for the implants were initiated with a 1.95-mm long stop pilot drill provided in the 3D Diagnostix Guided Surgical Kit.

With the combination of their corkscrew thread, built-in platform switching and apical design, the ET III SA implant system was utilized in this particular case (Figure 11). According to the manufacturer, the enhanced SA (sand-blasted and acid-etched) surface of this implant has shown a substantial quickening of gene expression, cell differentiation, and proliferation that are essential to osseointegration, meaning faster bone healing and earlier loading times. Other implant systems on the market with high initial stability may include but are not limited to Engage (OCO Biomedical), NobelActive (Nobel Biocare), Seven (MIS Implants Technologies), I5 (AB Dental USA), Conus 12 (Blue Sky Bio), and AnyRidge (Integrated Dental Systems).

In the upper arch, four 3.5 x 11.5 mm ET III SA dental implants were placed in the areas of Nos. 6, 8, 9, and 11 to eventually support a maxillary palate-free metal-reinforced denture (Figure 12). A baseline Implant Stability Quotient (ISQ) reading was taken of these implants utilizing the Osstell ISQ unit. Since the initial readings were less than 55, and the quality of bone in the anterior maxilla was not ideal, short healing caps were placed to prevent any load or lateral forces on the implants. Any residual areas around the implants or in the sockets were grafted using a putty blend of cortical mineralized and demineralized bone grafting material (Maxxeus) to optimize the area for regeneration. Primary closure was achieved by suturing the tissue with 3.0 mm Black Silk Sutures (Blue Sky Bio).

The immediate denture was relined using UFI Gel SC (VOCO America) material. Composed of a vinyl polysiloxane (VPS), it only required application of a bonding agent to the inner surface to ensure adhesion of the soft liner to the hard acrylic denture base.

A similar protocol was utilized in the lower arch using the Physics Forceps for the extractions and a CT-based surgical pilot guide for the implant preparation following bone leveling (Figures 13 and 14). Here, the initial ISQ values were very high, as expected from the quality of bone and high insertion torque. Because of this, temporary PEEK abutments were placed into the implants (Figure 15) and a provisional fixed restoration cemented using a provisional resin cement (TempBond Clear [Kerr]).

Four days postoperatively, the patient returned with some slight swelling, but no discomfort was reported. She was already very pleased with her provisionals, maxillary immediate denture, and lower implant-supported fixed bridge. A panoramic radiograph (PANOREX) was taken at this point to document the placement and position of the implants (Figure 16). The next step in her treatment would consist of impressions for the definitive upper and lower restorations, approximately 4 to 5 months postoperatively.

Approximately 16 weeks after implant placement, the patient returned for the prosthetic phase of her treatment. The gingival tissue around the implants looked healthy, so the healing caps were removed and the implants evaluated. Each implant was tested with the Osstell ISQ (Osstell) implant stability meter (Figure 17) followed by placement of a LOCATOR attachment abutment with a 3.0-mm gingival cuff height.

Using the Osstell ISQ meter, which uses resonance frequency analysis, we measured the stability of each implant by connecting the Smart Peg (Osstell) and then scanning it with the tip of the handpiece. There are a variety of different Smart Pegs, which are specific to the type of implant being used. The measurements for each implant are recorded in a noninvasive manner and within a few seconds.2 All 11 implants tested with ISQ values higher than 77, meaning very good osseointegration (Figure 18).

Since all the dental implants were integrated well, impressions were taken for the definitive restorations. In the upper arch, impressions were taken of the LOCATOR attachment abutments with specialized impression caps that snap onto the LOCATOR with a medium-body VPS impression material (Take 1 Advanced [Kerr]) and an All-in-One Clear Implant Tray (Good Fit) (Figure 19).

In the lower arch, full-arch impressions were taken using Instant Custom C&B Trays (Goodfit) and a heavy and light VPS impression material (Take 1 Advanced). Bite relations, as well as instructions for size, shape, and color for the definitive restorations were forwarded to the dental laboratory team.

Since the overdenture would be opposing PFM fixed partial dentures (FPDs), a nanofilled composite material was selected for the denture teeth (Figure 20) named PhysioStar NFC+ (Candulor [Ivoclar Vivadent]). These denture teeth have outstanding physical material properties, such as abrasion resistance and breaking strength. According to the manufacturer, the greatest advantage of this material is the excellent abrasion resistance, which is significantly greater than that of materials previously used for denture teeth.

Within 3 weeks, the custom abutments for the lower arch, the lower fixed bridge, and the upper palate-free metal reinforced overdenture were delivered from the dental lab. Utilizing an insertion jig, the abutments were screwed into their corresponding implant.

The full-arch PFM restoration was tried in (Figure 21) and radiographs taken to ensure complete seating. Once confirmed, the FPD restoration was cemented with Premier Implant Cement (Premier Dental Products) and allowed to harden. Once set, the excess cement was removed with a plastic implant scaler (Premier Dental Products) (Figure 22). Once the patient was pleased with the aesthetics and bite of the overdenture, the processing inserts from the LOCATOR housings were removed and replaced with the more retentive blue inserts (Figure 23). She was instructed about its care and use in eating, speaking, and biting. Once treatment was complete, a PANOREX radiograph was taken (Figure 24).

The patient was very pleased with the result and commented on how much more confident this new enhanced smile made her feel. (Figure 25).

IN SUMMARY
The goal of dental implant rehabilitation is to bring the patient’s dentition to proper aesthetics, form, and function. Of course, this is best achieved when the dental provider has a clear picture of the end result. With the recent introduction of new 3-D diagnostic and treatment planning modalities in implant dentistry, accurate planning as well as precise placement of implants that are restoratively driven can be achieved.

With a variety of different software and associated surgical instrumentation available, dental implant diagnosis and treatment has become more simplified. This development has created an interdisciplinary environment in which better communication and precise execution leads to better patient care and outcomes.


References

  1. Orentlicher G, Goldsmith D, Abboud M. computer guided planning and placement of dental implants. Atlas Oral Maxilofacial Surg Clin North Am. 2012;20:53-79.
  2. Rodrigo D, Aracil L, Martin C, et al. Diagnosis of implant stability and its impact on implant survival: a prospective case series study. Clin Oral Implant Res. 2010;21:255-261.

Dr. Nazarian maintains a private practice in Troy, Mich, with an emphasis on comprehensive and restorative care. He is a Diplomate in the International Congress of Oral Implantologists. His articles have been published in many of today’s popular dental publications. He is the director of the Reconstructive Dentistry Institute and has conducted lectures and hands-on workshops on aesthetic materials and dental implants throughout the United States, Europe, New Zealand, and Australia. He is also the creator of the DemoDent patient education model system. He can be reached at (248) 457-0500 or via the website aranazariandds.com.

Disclosure: Dr. Nazarian reports no disclosures.