Introduction

Immediate placement and immediate loading in full arch rehabilitation represents a valuable and established treatment option over staged and delayed protocols^3–5. While preferred by patients, they do require adequate bone volume and quality to ensure primary stability and implant loading ^6–8. However, such conditions may not always be present, especially in the posterior maxilla⁹. As a result, treatment approaches require carefully balancing the clinical prognosis and success with increasing patient expectations. In this situation, using strategic teeth intended for extraction as an abutment for the temporary restoration or short implants in areas of missing bone volume can represent valuable tools to prevent patients from requiring a removable prosthesis or undergoing invasive bone augmentations². The choice of implant design can also significantly influence the treatment strategies in such situations. The recent introduction of the BLX implant macro design has allowed for achieving adequate implant stability even in situations with poor bone quality^10–14. The design concept has also been successfully exploited for short implants supporting less invasive procedures without extensive bone regeneration and with a potentially improved patient acceptance^2,15. With TLX short implants that use the same endosseous implant macro geometry, a tissue-level design option has become available and may help reduce bone resorption by relocating the implant-abutment connection away from the bone level^16,17.

The following clinical case illustrates how transitional tooth-supported provisional prosthesis and short TLX implants can be efficiently exploited as tools to avoid complex reconstructive procedures for the immediate full-arch rehabilitation of a patient with compromised preconditions.

Initial situation

The patient, a 60-year-old female, non-smoker, in good general health (ASA class 1), presented in our clinic with a chief complaint of pain and swelling in her right upper jaw. She previously underwent two failed regenerative surgery in the first quadrant 1 year and 6 months earlier.

As illustrated in Figure 1, the patient presented with a pronounced detectable swelling in the lower third of the right face-half.

Intraoral examination revealed temporary resin prostheses in positions 1.2 to 2.3 with a cantilever extension in position 1.3. Teeth in positions 2.3 to 2.7 and 1.7 were restored with porcelain metal crowns, and positions 1.3 to 1.6 were edentulous.

Teeth 1.7 and 1.8 were very mobile. The edentulous areas of quadrant 1 displayed oedema with a purulent exudate (Figure 2).

Diagnostic cone-beam computer tomography (CBCT) showed the presence of graft material and membrane screws in quadrant 1; teeth 1.8 and 1.7 presented severely reduced bone support. Apical radiolucency of teeth 1.2-2.2 and 2.4 indicated the presence of endodontic periapical pathology. (Fig. 3)

The patient was informed of the need for a surgical intervention to immediately remove the material (membrane, graft and pins) and the adjacent dental elements in positions 1.8, 1.7 and 1.2 causing the inflammation followed by implant-prosthetic reevaluation after a couple of months.

Figure 4 shows the remnants of a titanium-reinforced membrane, membrane pins, graft material and teeth removed to address the acute inflammatory conditions.

After two months, clinical and radiographic data were collected to reevaluate the patient from a surgical and prosthetic standpoint and to elaborate treatment alternatives.

From a facial aesthetic and prosthetic point of view, the patient displayed a pronounced loss of vertical dimension and a low lip line at rest, without any exposure of the upper dento-gingival complex (Figure 5). The first quadrant was furthermore severely atrophied in the horizontal and vertical directions (Figure 6).

The intraoral scan files were used to digitally design a virtual wax-up with corrected and increased occlusal vertical dimensions by coronally displacing the upper occlusal plane. Dental crowns were designed to compensate for anatomic alveolar deficiencies in the first quadrant (Figure 6). The virtual wax-up was used to print a mockup to aesthetically and functionally validate the prosthetic plan as part of a patient try-on (Figure 7)

Treatment planning

Two treatment options for the upper arch were developed considering the patient's request for a predictable prosthetic solution without additional regenerative procedures and avoiding any temporary removable provisional conventional prosthesis:

1. The first treatment option comprised a fixed prosthetic first-molar-to-first-molar implant-supported rehabilitation based on 6 mm short implants in the first quadrant that avoided another augmentative procedures. Since the residual anatomical situation was a contraindication for immediate loading procedure, a 3-staged protocol involving a first set of tooth-supported provisional prosthesis delivered after implant placement, a second set of implant-supported temporary prosthesis delivered after teeth-extraction and the final prosthesis following tissue healing was proposed.
2. The second treatment option was based on delivering an implant-supported overdenture. This strategy would increase labial support without requiring new implants in the first quadrant. 

The mandible treatment plan comprised replacing the existing prostheses in positions 3.5, 3.4, 4.5, and 4.6 and bleaching and restoring positions 3.3 to 4.4 in composite resin. This strategy also included extraction of tooth 3.7 and implant placement in position 3.6.

Both maxillary options were discussed in the context of the mandibular treatment plan. The patient consented to the first option comprising the fixed maxillary full arch restoration.

Surgical procedure

Implant positions were digitally planned and transferred to the surgical field using guided and conventional surgical workflows in the first and second quadrants, respectively. The procedures were performed under local anaesthesia.

Specifically, in quadrant 1, one 3.75 x 8 mm and two 3.75 x 6 mm TLX implants were placed in positions 1.2, 1.5 and 1.6, respectively, using guided surgical placement (Figure 8).

In quadrant 2, teeth 2.2, 2.4 and 2.7 were extracted and 3.75 x 12 mm, 3.75 x 10 mm and 4.5 x 8mm TLX implants were immediately placed in the corresponding extraction sockets. All implants reached adequate primary stability (Figure 9).

Connective tissue was harvested from the palatal flap in the first quadrant and sutured to the buccal maxillary aspect to increase the buccal soft tissue thickness (Figure 10).

Next, primary wound closure was achieved for submerged implant healing, and a provisional canine-to-first-molar resin prosthesis supported by teeth 2.5, 2.3, 2.1 and 1.1 was relined, polished and delivered. Prosthetic non-functional cantilevers crowns in positions 1.2-1.3 and 2.6 extended the prosthetic bridge (Figure 11).

Prosthetic procedure

After 3 months of healing, the implants were exposed, and adequate osseointegration was verified. Conventional impression of the position of the upper implants was next taken and used to fabricate an Implant-supported, metal-reinforced provisional maxillary prosthesis. Before extracting the remaining teeth, the precise passive fit of the provisional prosthesis was radiographically and clinically verified (Figure 12 upper left and right). Teeth 1.1, 2.1, 2.3 and 2.5 were extracted, and the extraction sockets were wound closed by sutures. The prosthesis was relined, polished and screwed onto the implant head (Figure 12 lower left and right).

After bleaching, lower incisors and canines were restored were restored with composite using the upper provisional as a reference and the posterior provisional crowns were replaced using anterior lower teeth as reference (Figure 13).

After three months, the implant-supported upper provisional restoration was reevaluated from a functional and esthetic standpoint and considered adequate. Soft tissue healing and maturation were also evaluated as optimal. The provisional prosthesis was used as a reference for fabricating and delivering a metal-ceramic definitive restoration (Figure 14). Panorex was taken after delivery of the final restoration showing the perfect integration of the upper and lower left TLX implants (Figure 15).

Summary and conclusions

This case demonstrates how the use of TLX short implants in the posterior segments of the upper arch can effectively prevent patients from undergoing invasive and long, multistep and invasive reconstructive procedures. Likewise, the applied protocol illustrates how the use of a first set of teeth-supported provisional restoration may prevent patients from experiencing removable provisional prosthesis when immediate loading procedure is not feasible ensuring a patient-friendly transition from a failing dentition to an implant-supported fixed restoration.