Immediate loading with a provisional complete maxillary restoration using guided surgery protocol 2 November 2015

Clinical situation Immediate loading procedure

Author: Jean-François Barret & Romain Barret

Surgery: Dr Hadi Antoun
Clinical monitoring: Dr Michel Karouni
Prosthetist: Dr Laurent Kohn
Laboratory: M. Romain Barret, Paris

This study presents the immediate loading technique of a complete maxilla. Once the patient's case study is achieved, a surgical guide is performed with the NobelCinician (Nobel Biocare) software for implant planning.

This software assimilates mucosal and anatomical bone data as well as prosthetics, ensuring optimal implant planning virtually. The output renders a surgical and prosthetic guide and is used to craft the provisional prosthesis before heading to the surgery itself. Thanks to the output and to the prosthetic planning done by the dental surgeon, a guided restoration of the maxilla implant is possible. Crafted at an earlier stage thanks to the output, the provisional prosthesis is immediately installed for 6 months, guaranteeing the bio-integration and the optimal durability of the implants. Every step of the laboratory prosthetic phases are detailed in the article.

Figures 1 and 2: At the initial clinical situation and panoramic radiography, there is a complete edentulous maxilla and a partially edentulous mandible with residual conservable teeth after initial treatment and periodontal treatment.

Figures 3a and b: Fitting of the complete denture and aesthetic validation from the patient.

Figure 4: Markings of 8 radiopaque gutta percha points on the patient's current prosthesis which has been first validated and perfected for a functional and aesthetic optimization in order to transform it into a radiographic guide.

Figures 5 and 6: Creation of a duplicate of the patient's current complete overdenture by the same manufacturing facility as for the surgical guide (Stereolithography technology) for the articulator.

Figures 7 to 10: Implant planning with NobelClinician software which will lead to the simulation of the ideal implant position in relation to the available bone volume and to the prosthetic project materialized by the complete denture.

Figure 11: Surgical guide: guided cylinders with pin placed onto the drills provide an accurate placement of the implant replica. The guide is then treated in the same way as the impression of an implant-borne prosthetic

Figures 12 to 14: Casting is done in two stages: first, application of soft silicone Gingifast Elastic around the replica; second, a plaster cast covers the rest of the hard palate. We now have the master model. Placement of the Multi-Unit Abutment, Regular Platform (NobelBiocare) of standard diameter on the master model. Conical abutments allow to make a screw-retained multiple unit prosthesis.

Figure 15: Placement of the previously polished reinforcement cast (Co-Cr), then resin placement.

Figures 16 and 17: Aesthetic cast wax, resin teeth and "Genios" composite. The morphology and the shades have been selected according to the current prosthesis and the patient's wish to preserve her smile.

Figures 18 and 19: Burring, resin finishing and flexible silicone (Gingifast Elastic®) is injected onto the "gingival" part of the chambers in order to temporarily fix the provisional bridge cylinders on the master model. The "occlusal" part of the chambers is left unobstructed.

Following the prosthesis work executed in the laboratory, the surgical part starts with implant placement first, then with the immediate loading of the provisional bridge.

Figures 20 to 23: D-day, drilling and implant placement through the surgical guide without any incisions or stitches (flapless technic) and Multi-Unit RP abutment placement tightened to 35 Ncm.

The temporary cylinders are screwed onto the abutments. The flexible silicone corrects the positioning differences between the implant project and the clinical situation. Once the occlusion is checked, the protection screws are placed onto each cylinder. Auto-polymerized resin is injected onto the unobstructed nozzles.

Figures 24 and 25: Cementation of 6 provisional components to the provisional prosthesis with Ufi Gel Hard C® resin injected through the occlusal part.

Figure 26: Controlling and screwing of the provisional prosthesis tightened to 15 Ncm on the MUA abutments.

Figure 27: Occlusal view of the provisional prosthesis to assess the ideal emergence profile of the implants against the occlusal surfaces and the cingulums.

Figures 28 to 31: Final clinical situation immediately after placement of the provisional bridge and the buccal flange to compensate alveolar resorption. The patient was able to receive a fixed transitional prosthesis immediately after implant placement but made prior to the surgery.