Case Study #1

Bone Block Grafting and Implant Dentistry (Fixed Prosthetics)

Figure 1

Fig 1. Pre-operative Panoramic radiograph

Abstract: Over the past several years, various techniques have been developed to assist the surgeon and restorative dentist to overcome limitations. One of the most difficult regions to restore back to function and esthetics is the anterior maxilla. In this newsletter, I will continue on with the topic of complex dental implant and esthetic rehabilitation which was discussed in the past several editions

Patient Profile: Robert is a 20 year old African male who presented with missing 21/22 and hopeless 11/12 (Fig 1).

Patient Concerns: In the past, Roberts options would have been limited to crown and bridge on 13-23 or flipper denture. From the initial consultation, Robert decided that once the teeth were extracted, bone grafting would be performed in preparation for dental implant placement. He also did not want a bridge because he felt he might have difficulty with maintenance. He also wasnt confident with the esthetics that a bridge from implants 12-22 might offer. He specifically wanted independent tooth replacement of teeth 12, 11, 21, and 22.

Figure 2

Fig 2. Flap reflection noting advanced bucco-lingual bone loss.

Pre-Surgical Workup:

Diagnosis: Missing 21/22 and fractured 11/12

Treatment Recommendations: Initially, the anterior maxillary 11/12 would be extracted and bone grafted in the anterior maxilla. Robert would then wear a partial denture (flipper) for approximately 4 months duration for the bone healing and then another 3 months duration for the healing of follow-up dental implants. Finally, he would receive individual crowns on the implants 12-22.

Surgical and Prosthetic Restorations

Upon reflection of a full thickness flap and extraction of teeth 11/12, it was noted that there was insufficient bone for dental implant placement (Fig 2)

In order to augment the pre-maxilla to accept implants, bone block bone grafts were necessary with stainless-steel screw stabilization (Fig 3 & Fig 4)

Panoramic radiograph demonstrating fix stainless steel stabilization screws in the bone block allograft (donor bone graft) (Fig 4)


Figure 3

Fig 3. Bone block graft with 5 stabilizing screws

Figure 4

Fig 4. Panoramic showing bone block and stainless steel stabilizing screws


Six months post-operative, the soft and hard tissue healing is complete (Fig 5)

A full-thickness flap reveals the healed bone block grafts. The stainless steel screws are removed and four Nobel Biocare implants are inserted according to previous wax-up and surgical guide (Fig 6)

Figure 5

Fig 5. Healing bone block site in anterior maxilla

Figure 7

Fig 6. Dental implants inserted after stainless steel screws are removed at 4 months post-bone block healing


Figure 7
Fig. 7 Final radiograph of implants and crowns 12-22

Prosthetic Procedures:

Final peri-apical radiograph of the for implants with four independent crowns in place (Fig 7)

Specific Technology Used: Bone block ALLOGRAFT from donor

Challenges

The biggest obstacles in such cases have to do with patient compliance. Robert had to be driven around for his appointments and many were missed. Its crucial that post-op appointments are attended regularly to ensure that no bone is exposed or soft tissue opens up revealing the stabilizing screws underneath. This would severely compromise the results. However, in this case, Robert was extremely compliant and did make most of his post-op appointments and the healing throughout was excellent. As well, any flipper or partial denture provisional appliance MUST sit passively over the bone graft and then implants. Otherwise, early overload may lead to failure of the bone block AND the implants.

Figure 8
Fig 8. Final Smile

Prosthetic Rehabilitation

Outcome: Patient final presentation after crown cementation for implants 12, 11, 21 and 22 (Fig 8 & Fig 9)

Conclusion: Bone block grafting is extremely technique sensitive but predictable. The use of bone block allografts typically used in spinal fusion surgery has been implemented for ridge augmentation since 2001 and is increasingly noted in the literature. The bone augmentation should be performed at the time of extraction if at all possible to minimize the number of surgical appointments for the patient. Once the bone heals and dental implants are inserted into bone augmentation sites, the grafted bone is of equal of harder quality than the patients original bone. This treatment may be performed in the maxilla or mandible and in the anterior or posterior sextants. For optimal patient comfort and recovery, intravenous sedation is recommended.

Patient Comments before and after procedure: Prior to treatment, Robert was very apprehensive about treatment. However, with intravenous sedation, he was able to relax throughout treatment and enjoyed great comfort throughout the treatment process.

Figure 9
Fig 9. Final Presentation

After treatment, he was thrilled to toss out his flipper partial denture and enjoy the fixed crowns which, as he stated, looked nicer then the original teeth.

What made our services stand out for the patient and the referring dentist is that Robert was referred to several specialists until he decided to proceed with us. The reason he allowed us to treat him had to do with the fact that he would be sedated throughout treatment (while others would not sedate him) and that we perform non-invasive bone block grafts (while other specialists wanted to harvest bone from his hip and chin). The referring dentist was surprised at what was possible with bone block technology today because he was always under the impression that all bone block grafts required patients to present to a hospital for removal of bone from the chin or him and transplanting such bone to the jaws. The dentist was also extremely pleased with the cosmetic result which was achieved.

The Business Case

This case continues to demonstrate the excellent collaborative work that can take place between the restorative dentist, periodontist and lab technician. The patient was very happy with the final results and even happier that he was comfortable and relaxed throughout every phase of treatment.

The final restorative costs were $8200 and the total for surgical cost totaled $13,500. The total cost was $21,700. Now, at the age of 20, Robert was attending college and had the confidence to spend more time with his friends and go out on more dates. He was more confident and smiled more as a result of this process. He was so pleased with the care received that his family referred several more patients to our practice for various periodontal and dental implant treatments.