Dr Yoshiro IIDA
TITLE: Multiple tooth restoration with implants in the esthetic zone. The novel approach utilizing tooth transplantation and osseointegration for the perfect esthetic outcome.
Introduction: Periodontal ligament(PDL) on natural tooth roots is capable of remodel and maintain the alveolar bone. Therefore, single implant restoration is more predictable to maintain the papilla height because of the presence of PDL on natural tooth next to the implant. It is hypothesized that transplanted natural roots located next to the implant can also maintain the papilla height in the esthetic zone. The aim of this case report is to investigate if tooth transplantation is practically effective to achieve the esthetic outcome in the multiple tooth missing case by avoiding the necessity of consecutive implant positioning.
Method: This case has had multiple tooth fractures. First examination revealed hopeless prognosis on #11 and #24, required extraction and reconstruction with implants in the position of #11, #22 and #24. Extractions of #11 and #24 were performed, followed by the tooth transplantation from #11 into #21 position so that 3 implants could be placed in the position of #11, #22 and #24.
Results: All surgical procedure has been successfully performed without any complication. This case has successfully achieved perfect esthetics with 100% patient satisfaction. 18 months after the delivery of final prosthesis, the interproximal bone height has been maintained around implants and transplanted tooth roots. Transplanted tooth root has not shown any pathological changes such as internal or external root resorption so far.
Conclusion: Tooth transplantation can be an effective maintain bone height adjacent to the implant due to its biological effects of PDL. Also the modification of the multiple tooth defect by the tooth transplantation is able to avoid the consecutive implant positioning, which creates challenging situation for the perfect esthetics. Thus, tooth transplantation can be biologically sound technique to establish the perfect esthetic outcome for multiple implant restoration as a predictable manner.
1: 32 years old Asian male, who have had a trauma on mid face by the car accident, presented for the initial consultation. Clinical observation revealed multiple teeth fractures including subgingival horizontal tooth fractures.
2: Tooth #21 and 22 were already extracted, #11 and #24 presented horizontal subcrestal tooth fractures. #23 was non vital, presenting fenestration at apical two-thirds with tooth mobility.
3: Initial examination revealed hopeless prognosis on #11 and 24, required extraction and reconstruction with implants in the position of #11, 22 and 24.
4: Gingival level of #22 was positioned apically.
5: Prior to the implant placement, alveolar ridge preservation at #21 and ridge augmentation on #22 were performed.
6: 3 months after ridge preservation of #21 and 22. Volume of alveolar ridge were well maintained.
7: We came up with the new strategies which combines avoiding adjacent implants and placing the PDL on natural tooth roots between implants, aiming at perfect predictable esthetic outcome on multiple missing case.
8: Following the socket healing, tooth #11 and 24 was extracted, planning the position of implants at tooth #11, 22 and 24, avoiding the implants placed side by side.
9: 4 months healing after the ridge preservation, extractions of #11 and 24 was underwent, followed by the tooth transplantation from #11 into 21 position then 3 implants were placed in the position of #11, 22 and 24 with surgical guide. Tooth root at #11 was transplanted to #21, placing the facial side of #11 on the palatal aspect, by flipping the tooth.#23 was extruded to the extent of the level, allowing whole tooth roots are enclosed within bony housing, then used for the root submergence technique.
10: Bone graft soarked with rhPDGF-BB was placed in the gap between the implant and buccal bone plate at #11 and #24, followed by the temporary abutment connection with appropriate soft tissue contour made for the complete socket sealing. Implant at #22 was connected with healing abutment as one step procedure. The transplanted tooth #21 was positioned at crest of buccal alveolar bone.
11: Immediate implant placement into the extraction socket of #11 with surgical guide.
12: Tooth roots at #11 was transplanted to #21, placing the facial side of #11 on the palatal aspect, by flipping the tooth.
13: Implant placement into the grafted site of #22 with surgical guide.
14: Immediate implant placement into the extraction socket of #24 with surgical guide.
15: After 5 weeks of tooth transplantation on #21, orthodontic extrusion was started to establish the symmetrical gingival margin to #11. Also #23 was started with orthodontic extrusion at the same time to expose sound tooth structure for the purpose of predictable root submergence technique.
16: 9 months after orthodontic extrusion, what is noted here is that the coronally positioned margin on #21, presenting the proof of the reattachment of soft tissue on the tooth root.
17: What is going on the vascular structure on PDL at transplanted tooth roots? According to the study by Tsumuraya 1990 using canine model, it was concluded that similar extent of vascular architecture and sharpey’s fibers was observed on replanted tooth compare to the natural tooth roots at 12 weeks.
18: After 9 months of orthodontic tooth movement, subepitherial connective tissue graft was performed at #11 to matching the buccal contour of #21.
19: After 9 months of orthodontic tooth movement, replantation was performed on #23 as a root submergence technique, and connective tissue graft was performed to create the thickness of pontic area at #23.
20: 14 months after implant placement, all preparation for the definitive prosthesis was completed.
21: 14 months after implant placement, final Impression was performed utilizing custom impression coping. Followed by final custom made abutments were set on #8, 10 and 12 and final prosthesises were delivered.
22: Definitive prosthesises were delivered at 19 months after the implant placement.
23: What is observed here was the transformation of this multiple tooth missing case to the simple single tooth missing case utilizing the tooth transplantation and root submergence technique. Moreover, the interproximal bone height was sustained by revasculalized PDL, ensuring the longevity of the esthetic results
24: This case has been followed more than 3 years, as we can see here on x ray presenting no pathological changes such as resorption or ankylosis so far.
25: This case illustrated the potential to achieve higher predictability for the multiple teeth implant restoration in the esthetic zone utilizing the natural tooth roots transplantation. To avoid sequential placement of dental implant, which creates a challenging situation for the perfect esthetics, the natural tooth roots transplantation can be the alternative technique to establish the sound esthetic outcome as a predictable fashion.
