Effect Of Sandblast-acid Etched Surface On Osseointegration At Interface Between Micro-screw Implants And The Bone And Expression Of TGF-β1、NGF

Objective Recently，researchers tried to change surface characteristics of dental implants as aprosthesis means and were successful in improving the stability on the base of“osseoinergration”. However，the technology has seldom been used in micro implants as aanchorage means in orthodontics，and some micro implants loose or dropped during theorthodontic treatment. In present study the micro implants disposed with SLA were implanted indogs’ mandible. Then a histological and immunohistochemical study were put up to investigatethe possible role of this special implant in clinical application.Materials and Methods3male beagle dogs were selected which were healthy，1years old.The dogs were grouped randomly.18micro implants were implanted in the dogs’ mandible，9ofthem were disposed with SLA，3SLA implants in one side of the mandible and3normal in theother side. One of the dogs was immediately operated at a general anaesthetic，and the secondone was operated after4weeks，the third one after8weeks. All the dogs were killed after8weeks and the bone tissue samples were collected. The bone samples were analyzed by HEstain，immunohistochemical stain and Meta-Morph imaging analyzing system.Results HE stain：A large mount of active osteoplast can be seen at the interface between SLAmaterials and the bone in2weeks group，but in4weeks group between the normal materials andthe bone. Earlier formation of synostosis can be seen in SLA sections. Immunohistochemicalstain：Expressions of TGF-β1in the interface between SLAmaterials and the bone are the best in2weeks group，than declined in4weeks group and8weeks group；expressions of TGF-β1in theinterface between the normal materials and the bone are the best in4weeks group，than declined.Expressions of SLA materials are better than the normal materials in2weeks group and4weeksgroup. Expressions of NGF in the interface between SLA materials and the bone are the best in2weeks group，than declined：expressions of TGF-β1in the interface between the normal materialsand the bone are the best in2weeks group and4weeks group，than declined. Expressions ofSLA materials are better than the normal materials in2weeks group but lower in4weeks group.Conclusions Implants disposed with SLA can accelerate the formation of synostosis at theinterface between implants and the bone，which can reduce the time before loading inorthodontic clinic. The biocompatibility of SLA implants is better than normal implants.