Simultaneous extraction implantation, immediate aesthetics and guided bone regeneration 15 January 2017

Simultaneous extraction implantation, immediate aesthetics and guided bone regeneration

The implant-borne rehabilitation is nowadays considered a reliable and predictable technique. Initially, burying the implant was a prerequisite to ensure osseointegration. Subsequently, several studies have shown that this state of osseointegration can be achieved without completely burying the implant, thus simplifying the operative procedure.

The application of new technologies to implants, both at the surface state and in the architectural design, have led to shorten considerably the treatment time and to consider, in some cases, an immediate fixed provisional prosthesis.

The changes in post-operative protocols towards an immediate loading and aesthetics have offered comfort and satisfaction to patients both aesthetically and functionally. The use of removable prosthesis often poorly accepted by patients is no longer essential in certain clinical situations.

Anamnesis

A healthy, non-smoking, 58 year-old patient was referred to the practice for an implant-borne consultation on 24 and 25.

Clinical examination

During the exobuccal clinical examination, a harmonious distribution of the facial regions, an absence of pathologies at the temporomandibular joints, a well tolerated vertical dimension of occlusion and a stable occlusion are noted (Fig. 1).

Figure 1 : Front view where the absence of perleches or intercommissural folds are noted, signs of a healthy vertical dimension of occlusion.

The endobuccal examination shows a satisfactory oral hygiene, the advanced loss of an attachment at the maxilla molar sectors and absence of teeth at 37 and 47. There are no caries. (Fig. 2 a to c).

Figure 2 a to c : Initial clinical view with the presence of infiltrated crowns at 24 and 25 is observed as well as an inflammatory peripheral gingiva and an inadequate shade.

We also note the prior implant-borne treatments of 11, 21, 36 and 46. The crowns are well placed with a healthy and harmonious peri-implant mucous.

A closer observation of teeth 24 and 25 shows infiltrated crowns, a retracted and inflammatory gingiva, associated with a deep probing of 6 to 8 mm on 24.

The 15 mm mesio-distal space and the 9 mm interarch height provide good conditions for considering an implant solution.

X-ray examination

The panoramic radiography (Fig. 3) shows a widespread horizontal osteolysis in the mid-third of the roots. This is more pronounced in the maxilla molars. A moderate general chronic periodontitis is diagnosed with a severe case at the maxilla molar sectors.

Figure 3 :Panoramic dental X-ray with a widespread horizontal lysis, the absence of 37 and 47, and the implant-borne restorations.

The implant treatments are well integrated. The proximal bone levels are optimum except at the implant level on 36 where we observe a filling defect which does not seem to be harming the implant as there are no clinical signs of otherwise, corroborated by the stability of the bone remodelling.

At 24, the future implant site, there is a consequent circumferential osteolysis linked to a radicular resorption, possibly due to an endoperiodontal lesion. At 25, a mid-third horizontal osteolysis is observed, along with an enlarged ligament space and an infiltrated crown (Fig. 4).

Figure 4 :Retroalveolar X-ray showing the affected levels of 24 and 25. There is a severe distal osteolysis on 26. The absence of mobility of 26 and 27 is clinically observed.

On the maxilla CBCT examination, the residual osseous volume is satisfying on the two concerned sectors despite the vestibular osseous loss on 24. This makes it possible to have an immediate extraction implantation with a complementary guided bone regeneration (GBR) (Fig. 5 a and b).

Figure 5 a et b:The CBCT examination on 24 shows the near disappearance of the vestibular wall. Around 25, the bone plates are preserved. The available osseous volume are respectively of 6.73x14.18 mm for 24 and 8.59x11.19 mm for 25.

Treatment plan

It was decided to extract 24 and 25 and to place immediately two implants with a GBR.
With regards to the patient’s aesthetic requirements, it was opted for a fixed and immediate temporisation depending on the achieved primary stability.

Surgical phase

An intrasulcular incision completed with a mesial releasing incision is performed to separate a full-thickness flap in order to visualise the vestibular osseous loss. The extractions are delicately performed in order to preserve the residual vestibular cortical bone as much as possible. The dental alveoli are thoroughly cleaned and irrigated with Betadine. Then, the drilling is performed using a classic protocol in the buccal corridor slightly to the palatal. Two implants are placed (Fig. 6);

Figure 6 : Operating view which shows two NobelActive (Nobel Biocare) implants in place with a vestibular default on 24 and a crater around the implant on 25.

24: NobelActive RP 4.3X13 with a final insertion torque of 45 N.cm
25: NobelActive RP 4.3x11.5 with a final insertion torque of 45 N.cm

Two Multi Unit Abutments (Nobel Biocare) of 1.5mm in height (MUA) tightened to 35 N.cm and two provisional components are placed at this stage.

The created crater between the implant and the external cortical bone along with the vestibular dehiscence are filled with 0.5 g of bovine hydroxyapatite (fine grains Bio-Oss®, Geistlich) (Fig. 7).

Figure 7:MUA placement along with the rotational provisional components. The filling of the per-implant crater and the coating of the exposed spirals is guaranteed with Bio-Oss® (Geistlich).

A resorbable membrane is then placed to maintain the substance and to guide the osseous regeneration of the lost crestal area of the vestibular table (Fig. 8). It is sutured on the palatal.

Figure 8: Placement of a collagen membrane to cover and maintain the biomaterial.

Finally, the discontinued and tensionless sutures are performed with a 5/0 Velosorb resorbable thread (IPP Pharma) to close the edges of the wound. The releasing incision is sutured with a 6/0 Velosorb resorbable thread for the aesthetics of the scar.

A post-operative x-ray control is performed (Fig. 9).

Figure 9: Post-operative retroalveolar X-ray with the abutments and the provisional components in place.

Immediate temporisation

The temporisation stage immediately follows the surgical phase.

The crowns made from a mould are emptied and relined on the provisional components (Fig. 10 a and b).

Figure10 a et b : Vestibular and occlusal clinical views of the realignment of the crowns on the provisional components.

The emergence profile is sculptured concavely by progressively adding resin out of the mouth. The edges are rough-hewed and carefully polished (Fig. 11 a and b).

Figure 11a and b : The provisional crowns are removed, more resin is added and polished.

The cemented provisional restorations are screw-retained at 15N.cm on MUA and statically and dynamically loaded under occlusion (Fig.12).

Figure 12: Clinical view of the screw-retained provisional crowns on conical prosthetic abutments.

Prosthetic phase

The final prosthesis is started 4 months after surgery and after having validated the incorporation of the implant.

A Pick-up impression (Fig. 13) is performed using an individual impression tray from a primary impression using a polyether (Impregum™).

Figure 13: Retroalveolar X-ray to check the position of the impression coping. We observe the proximal osseous stability 4 months after the immediate aesthetics.

Although not always necessary for simply two adjacent implants, a plaster core validates the precision of the impression and the plaster casting (Fig. 14 a and b).

Figure 14 a et b: Vestibular and palatal views of the plaster core on the working model.

Figure14 c et d: The copings surmounted by the plaster core are repositioned on the abutments to validate the impression.

The shade is then chosen and validated by the patient (Fig. 15).

Figure 15: The shade is chosen and then validated by the patient and is transferred to the laboratory.

The passive metal-ceramic bridge thus obtained is screw-retained on abutments and tightened to 15N.cm. The occlusion is checked (Fig. 16 a and b).

Figure 16 a and b : Clinical view of the finished prosthetic restoration and the smile. We observe the aesthetic incorporation as well as the maintained vestibular curving contour with regards to the two implants.

Clinical and x-ray monitoring is planned once a year (Fig. 17).

Figure 17: Retroalveolar X-ray monitoring shows an osseous stability around the implants at 1 year.

Discussion

This increasingly used sensitive and advanced surgical approach is scientifically and clinically validated. It requires surgical experience to adapt to the pre-operative anatomic conditions and to further ensure optimal conditions for success and achievement. A close observance is primordial during the healing phase.

The main key to the success of this type of treatment is the primary stability of the implant. It must withstand micromovements caused by food intake, tongue and cheeks.

To date, there is no consensus on the value of the minimum surgical insertion torque. Studies vary between 35 and 80N.cm. In our practice, we admit to an aesthetic loading of implants from 30-35N.cm.

Finally, associating a GBR to the immediate aesthetics seems to give satisfactory results especially when the bone defect does not come out of the osseous casing.

Keywords: Dental implant, guided bone regeneration, immediate extraction implantation, immediate aesthetics

Authors

Dorra Dey Daly

Doctor in dental surgery,
Postgraduate degree in surgery and implantology
Paris 5 University

Michel Karouni

Doctor in dental surgery,
Postgraduate degree in Periodontics and Prosthesis
Paris 7 University

Hadi Antoun

Private practice limited to Periodontology and Implantology
Paris, Founder of the IFCIA Institute

Simultaneous extraction implantation, immediate aesthetics and guided bone regeneration 15 January 2017