There is an increasing role for orthodontic mini implants as an anchorage device in orthodontic practice In many occasions, orthodontists may have to reuse orthodontic mini-implants (re-implanting again ) after sterilizing them by moist heat. The aim
of this research was investigating the effect of re-implantation and moist heat sterilization on the primary fixity of orthodontic mini-implants> Two lengths of mini-implants (6-7mm) (ti – 6A1 – 4A1 ) and two shapes (normal and dual thread ) were used and inserted in artificial bone (saw bone ) a first time and after sterilizing them by moist heat (Autoclave) a second time , in an insertion angle of 90 . The insertion and removal torque and periotest score (periodontium test device ) were measured to assess the primary fixity ( after implanting in the first time and the second time ) The results showed a decrease in the primary fixity after re-implanting and sterilizing by moist heat , but it still enough for using it a second time effectively to provide needed orthodontic anchorage for both two lengths and two shapes.
