A Technique Innovation And Initial Animal Experimentation Of The Distraction-implant

Objective We would design and manufacture the distraction-implant which combine the distraction apparatus and the implant. Using the experimental study to observe the effect of distraction osteogenesis and the hard-soft tissue around the implant.Materials and Methods Design and manufacture the distraction-implant. The bilateral first and second premolars and first molars were extracted in six adult Beagle dogs. After 3 months, a rectangular shaped osteotomy on the both side of the edentulous alveolar bone was carried out and 3 distraction-implants which are 3.3mm in diameter were placed on each side. After one week, the alveolar ridge was vertically augmented at 0.5mm/d by distraction for eight days. Following 4,6,12weeks fixation, macroscopic, histological, radiographical evaluations and torque tester,ISQ(implant stability quotient) value were carried out.Results Peri-implant distraction region was filled by new born bone tissue, and the fissure of bone was disappear. Despite the 4 weeks group, the other two had well-distributed and hard new bone. The soft tissue around the implants were healthy and the BOP (bleeding on probing) evaluated in the gingival were negative. All implants have great Osseointegration, and the results of torque tester are bigger than 35Ncm. Average ISQ value result of 4 weeks is 58.5,8 weeks is 62.8,12weeks is 67.2. X-ray examination showed that distraction region in 4 and 8 weeks group had lower bone density than the bone nearby. And the 12 weeks group had the similar bone density with the bone around. Hard tissue slices of the osseo-implant interface were observed. The distraction region of the 4 weeks group already had new woven bone. The 12 weeks group had numerous new born bone, and bone trabecula was abundant. The osseo-implant-screw interface got to be osseointegration. The interface of the non-distraction region of the implant from the 4 and 8 weeks group had increased marrow cavity. The 12 weeks group had no boundary with the surrounding bone.Conclusion We successfully design and manufacture the distraction implant. The dental distraction-implant has the ability of both distraction osteogenesis and osseointegration. During the alveolar distraction, the distraction-implant could be used to as an anchor. After the process of distraction, it could also be used to as a implant for restoration. It has good osseointegration with the bone around and has nice relationship with the soft tissue nearby. It is a promising technique for the clinical use of vertical augmentation of the alveolar ridge and tooth implantation and restoration...