When a patient presents with terminal dentition, we have a responsibility as dentists to help that person transition to edentulism by either providing a removable prosthesis or relying on the predictability of dental implants supporting a fixed prosthesis. There are a number of ways to achieve a functional and esthetic result for full-arch extraction cases, and the choice is usually based on the clinical situation, the patient’s desires, and the knowledge and experience of the clinician and dental team.1
The following case report illustrates the two-stage protocol of a maxillary dental reconstruction that was used to achieve very predictable results. The main advantage of this method is the ability to maintain normal speech and chewing functions for the patient.2
There are a number of ways to achieve a functional and esthetic result for full-arch extraction cases.
A 55-year-old male with a history of chronic periodontal disease presented to our office for treatment with loose and symptomatic teeth (Fig. 1). The clinical exam showed generalized severe bone loss with extensive mobility, rotation and drifting of the dentition. No temporomandibular joint noises, deviations or limited opening was detected, and there was no tenderness on palpation of the muscles of mastication. After the initial examination and radiographic evaluation, it was determined that bone loss had advanced to the point where extractions and full-mouth reconstruction were required (Fig. 2).
Figure 1: The patient presented with terminal dentition.
Figure 2: Panoramic X-ray revealed severe bone loss.
Maxillary reconstruction was pursued first. The upper prosthesis would have to be fixed rather than removable, and the patient did not want to have to leave the dental practice without teeth during any phase of treatment. The patient’s needs and desires limited the feasible options to either an immediate load implant reconstruction, or a staged extraction and delayed-load procedure.3 The staged delayed-load option was elected.
The first task in the treatment process was to devise a staged treatment plan. The staged protocol designed for this case allowed the clinician to proceed with straightforward treatment steps. After initial conservative periodontal care, some teeth would be extracted, while others would be temporarily maintained as natural abutments. To ensure long-term success, it is important to keep the occlusion of implant restorations within the patient’s physiological limits and provide optimal implant load.4 The natural abutments would serve a dual purpose by providing an occlusal reference and supporting a provisional prosthesis. After implant placement and osseointegration, the natural tooth abutments would be extracted, and the final prosthesis would be delivered.
Some teeth would be extracted, while others would be temporarily maintained as natural abutments.
Initial therapy was performed and included scaling and root planing. Then, a cone-beam computed tomography (CBCT) scan was obtained and studied to determine the amount of available bone and visualize the anatomy pertinent to implant placement (Fig. 3). A set of models mounted in centric relation was used to create a diagnostic wax-up of the desired end result for the maxillary arch (Figs. 4a, 4b). Using Imprint™ 3 VPS Impression Material (3M™ ESPE™; St. Paul, Minn.), a vinyl polysiloxane impression was taken of the wax-up to aid in the fabrication of a temporary fixed bridge.
Figure 3: Preoperative CBCT scan.
Figure 4a: Casts were mounted on a semi-adjustable articulator.
Figure 4b: A diagnostic wax-up was prepared.
The patient was then scheduled for the first series of extractions. Due to the patient’s irregular mandibular plane, some enameloplasty and occlusal adjustments were performed.4 The selected teeth were prepared to support the temporary, cement-retained bridge. An impression was taken and sent to the laboratory for fabrication of the bridge from poly(methyl methacrylate) (PMMA).
Teeth #2, #4, #6, #8, #9, #11, #13 and #15 were atraumatically extracted with a periotome and forceps. Implants were immediately placed in each extraction socket except for #2 and #15. Bone grafts were used to treat any spaces that remained in the sockets after implant placement in order to shorten the treatment time and preserve a maximum amount of bone.5 The implant sites were covered under the soft tissue, and the temporary bridge was cemented to allow the patient to function for an extended time period while the implants osseointegrated (Fig. 5).6,7 The placement of the implants and the tooth preparations for the temporary fixed bridge are shown in the panoramic film (Fig. 6).
Figure 5: Temporary bridge after extraction and implant placement.
Figure 6: Panoramic X-ray showing implants placed between terminal dentition.
Figure 7: Custom abutments were placed after the patient’s remaining maxillary teeth were extracted, helping to maintain natural soft-tissue contours.
At the implant placement visit, Imprint 3 VPS material was used to take a fixture-level impression that was sent to the lab in order to fabricate Inclusive® Custom Implant Abutments (Glidewell Laboratories; Newport Beach, Calif.) and a PMMA temporary bridge that would be delivered after the remaining teeth were extracted.8
Four months later, the implants were uncovered and osseointegration was verified. The titanium custom abutments were tried in, and the seating was confirmed radiographically. The abutments were torqued to 30 Ncm, and the remaining teeth were extracted (Fig. 7). Then, the PMMA temporary bridge was cemented over the custom abutments.
During the next eight weeks, the occlusion was fine-tuned on the temporary, and adjustments were made for canine disclusion and proper bilateral contacts. The supragingival margins of the abutments were redefined using a round-end cylinder diamond bur with water coolant spray, and a new fixture-level impression was taken using an open tray. An impression of the approved temporary was sent to the laboratory to be used in the fabrication of the final bridge.
Figure 8: Final prosthesis cemented into place.
Figure 9: Patient smile showing final result.
The final prosthesis was fabricated as a layered-zirconia bridge.9 After trying in the framework and verifying the fit, RelyX™ Unicem 2 Automix Self-Adhesive Resin Cement (3M ESPE) was used to attach the bridge to the custom abutments (Fig. 8). The occlusion was checked, and minimal adjustments were required. Postoperative checks at three-month intervals revealed healthy tissue around the implants and stable bone levels. The patient has been functioning without any issues for over a year now and is very happy with the results (Fig. 9).
There are many restorative options available to implant patients today. Deciding which method to use in each case depends on clinical and patient demands. The treatment plan for this case proved to be advantageous because it sustained the patient’s dental function during treatment and provided the clinician with a means to easily maintain bone levels and reference points for verifying optimal vertical dimension. The main drawbacks of this two-stage approach are the extended treatment time and the need for multiple surgical steps.
Dr. Boudet would like to thank Glidewell Laboratories and Macron Dental Lab for their help in this case.