Initial Situation

A 62-year-old patient presented to the clinic with a porcelain fused to metal (PFM) bridge supported by teeth #13, #23 and #25; and a partial removable denture (Fig. 1-2). The patient suffered from the constant de-cementation of the bridge due to severe secondary caries of the roots.

Following the clinical and radiological examination, remaining roots #13, #11, #21, #23 and tooth #25 were diagnosed with secondary caries beneath alveolar socket margin and grade 3 mobility (Fig. 3-4).

In the mandible patient was wearing a partial denture and a PFM bridge from teeth #33 to #44. In radiological examination, an image compatible with a periapical lesion was observed on tooth #44. Moreover, the prosthetic superstructure was unsealed and moving.

The patient was aware that her remaining teeth needed to be extracted, as she was diagnosed and presented to the different treatment options by the referring dentist. She wanted not only a fixed solution but also to maintain her teeth shape and smile. Furthermore, she highlighted her preference of not having an artificial gingiva in the fixed denture and to have the second incisors concavities refilled, as well as the lip support maintained.

Treatment planning

Patient have had cone beam computed tomography (CBCT), intraoral scanning and photo portfolio for digital smile design (DSD) to prepare the treatment planning. CBCT and intraoral scans were used to plan the implants positions with coDiagnostiX® software (Fig. 5-6). The implants positions were planned in optimal prosthetic positions so the implant axes would be either on occlusal or palatal side of the future bridge. Due to reduced bone height in the posterior region, the implant in the site #26 was planned 6mm length and in #16 site 8 mm length. In order to obtain optimal primary stability, Straumann® BLX  implants were planned. Moreover, to achieve an ideal mechanical distribution, implants in the positions of second incisors, first premolars and first molars were planned. Following the digital treatment planning in coDiagnostiX®, the surgical guide was 3D printed (Fig. 7).

With the aim of meeting patient’s expectations regarding the appearance of the implant supported bridge, the intraoral scans and photo portfolio were used to design the teeth. The digital approach allowed to copy the shape, length and position of the failing bridge that the patient was wearing. The only modification was the length of the central incisors (1 mm longer), as the proportions of the teeth were more harmonious. That change was approved and appreciated by the patient.

Surgical procedure and scanning

Local anesthesia application was performed from vestibular and palatal side to anesthetize the hard and soft tissues. The existing PFM bridge was cut to leave only the first incisors (Fig. 8-9). At the first stage of the surgery the second left premolar was not extracted. Roots of the canines were carefully extracted (Fig.10). The fit of the surgical guide was checked (Fig. 11). The surgical guide was removed and crestal incisions were performed from the #11 to the area of #16 and from #21 to #25. A full thickness flap was elevated on both sides as an augmentation procedure was planned. Surgical guide was placed, and the osteotomy was performed according to the drilling protocol. Implants on the sites #16, #14, #12, #22 and #24 were placed (Fig. 12-14). Implant #16 was planned in the second stage of the surgery. The Screw-retained Abutments were screwed to the first five implants (Fig.15-16)

The following implants and Screw-retained Abutments were used:

• Straumann® BLX ø 3.75 mm RB SLActive® 6mm Roxolid®, #26
• Straumann® BLX ø 3.75 mm RB SLActive® 8mm Roxolid® #24
• Straumann® BLX ø 3.75 mm RB SLActive® 12mm Roxolid® #22
• Straumann® BLX ø 3.75 mm RB SLActive® 10mm Roxolid® #12, #14, #16
• Screw-retained Abutments, straight GH 2,5 in 1.2 – 2.2 positions
• Screw-retained Abutments, 17° angled GH 2,5 in 2.6 position

After placing the first five implants, augmentation with Cerabone® and Collprotect® membrane was performed on both sides from #11 to #16 and from #21 to #25 (Fig.17-19). Straumann® Emdogain® was placed around implants (Fig.20). Variobase® copings were mounted (Fig. 21). The scanning with 3Shape® TRIOS® was performed. The flap was closed with resorbable sutures. The patient received an intraoral scanning with the remaining teeth #11, #21 and # 25 as the prosthetic reference. After scanning the sutures were covered with Emdogain® (Fig. 22).

After the scanning remaining teeth were carefully removed (Fig. 23). Implant on position #26 was placed distally to the socket of #25. Sockets on positions #11 and #21 were filled with cerabone® and protected with a collagen sponge (Fig. 24). Patient was scanned again with all six implants.

Laboratory procedure

After the surgery, the lab technician received two scans and imposed them to the previously prepared digital wax up. The alveolar part of the bridge was designed respecting the emergence profile and accordingly to the tissue volume change after the bone augmentation. The temporary bridge was milled from polymethylmethacrylate (PMMA).

Treatment outcome

The bridge was delivered four hours after the surgery (Fig. 25-27). It was designed to support the soft tissue and immediately fill the sockets and give the patient a natural feeling (Fig. 28-29).

Patient received oral hygiene instructions, also to support soft tissue maturation; and was scheduled for regular check-ups.

The patient healed uneventfully and the gingiva matured. The satisfying outcome was already seen after one week (Fig. 31-32)

The mandible was restored three weeks after the surgery in the maxilla according to the Sobczak Concept® with Straumann Pro Arch. In the mandible, immediate implants placement were performed using Straumann® Bone Level Tapered (BLT) SLActive® implants.

Due to financial reasons, the patient did not have the chance to change from the temporary PMMA bridges to the final restorations for one year (Fig. 33). However, she maintained excellent oral hygiene, attended regular check-ups and was very satisfied with the treatment outcome.

Testimonial

“In my opinion the only and easiest way to maintain the tissues after extractions is immediate implant placement and immediate loading. That is why I developed a concept, that allows not only to keep and shape the tissues under the temporary bridge, but also allows the patient to experience and enjoy a non-removable teeth like full arch bridge made of multilayer PMMA with already proper design and function.

For that concept I need implants, that can almost guarantee primary stability of around 35 Ncm regardless conditions and that is for sure the BLX implant. Additionally, I would also recommend the new, easy to handle Screw-retained Abutments, which are crucial for my work. I have also re-discovered the healing capacity of Emdogain. It seems to facilitate the closure of the wound and augment areas I need in my treatment protocol.”