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Application of enamel matrix derivative in autotransplantation of an impacted maxillary premolar: a case report.

BACKGROUND
The success of tooth transplantation or replantation depends on the viability of periodontal ligament in the planted tooth. Mechanical injury to periodontal tissues frequently results in dental root resorption and dental ankylosis, which leads to the failure of transplantation or replantation. Enamel matrix derivative (EMD) has been recently used to induce periodontal regeneration. In this report, we show a clinical case of EMD application in the transplantation of an inversely impacted and immature tooth.


METHODS
An impacted second premolar was found in the right maxilla of a 16 year-old girl. The tooth was inversely impacted and the dental root was incomplete. When transplantation was carried out, EMD was applied to the periodontal tissues of the extracted premolar. The tooth was fixed at the correct position and the clinical condition was followed for evaluation for 6 months.


RESULTS
Radiographs after 3 months exhibited new bone formation surrounding the transplanted tooth. After 6 months, considerable growth of dental root was evident, periodontal ligament-like radiolucency appeared, the vital reaction of the planted tooth was detected, and there were no signs of root resorption or ankylosis.


CONCLUSION
Short-term results from this case indicate that EMD application was effective in the transplantation of an inversely impacted and immature tooth and that EMD might contribute to the growth of dental root and to the prevention of ankylosis.