Dentin Autograft into Atrophied Jaw for Tooth Autotransplantation

We previously reported the osteoinductive property of human demineralized dentin matrix (DDM) particles in the subcutaneous tissue of nude mice (male, 4 week-old) in IADR 2003. Until now, pioneering trials (8 cases) using autogenous DDM have been proceeding successfully. The human clinical studies were approved by the Ethics Committee, Health Sciences University of Hokkaido. Objective: To estimate the results following autotransplantation of DDM and non-functional tooth in a case of a congenital missing tooth clinically and radiologically. Methods: Patient: A 22-year-old female presented with reversed occlusion. A clinical examination revealed a congenital missing tooth (45) and an atrophied mandible in the section. Her medical history was unremarkable. By analyses including CT scan, a third molar with complete root formation (28, microdont) was selected as a transplant tooth and upper premolar teeth (14, 24) were extracted for orthodontic treatment. The conveniently extracted premolar tooth (14) was crashed in liquid nitrogen, washed in 1M sodium chloride, and demineralized completely in HCl solution (pH2.0) for DDM. The DDM particles were extensively rinsed in cold distilled water and lyophilized (particle sizes;1.0-2.0mm). The DDM were bacteria-free by bacteriological examination before use. Surgery: Splitting osteotomy of the cortical bone was performed in the atrophied mandibular region and osseous preparation for the tooth transplantation was carried out, using FLIALIT-2 implant system, under local anesthesia. Simultaneously, autogenous DDM were grafted on host bone after cortical perforations. Results: The DDM were received to host and the periodontal ligament space of the transplanted tooth could be seen clearly at 20 months postoperatively. This patient was successfully restored with the DDM autograft and the tooth autotransplantation. Conclusion: Autogenous DDM particles can be recycled and the DDM may be effective as osteoinductive collagenous matrics for bone regeneration.