COMPARISON OF FRACTURE TORQUE AND LEVEL OF FRACTURE OF TWO ORTHODONTIC MINI-SCREWS (AN IN VITRO STUDY)
BY
Shkar Fatih Mohammed
Kurdistan Ismail Ameen
Rayan Zrar Abdulqadir
Supervisor: Dr. Omer Sabah
Abstract
Obiective: To measure the maximum fracture torque and level of fracture of two commercially available orthodontic mini screw. Materials and methods: Twenty orthodontic mini-implants of {(Tomas. Dentaurm. Germany; GNI, Korean)] were inspected in an in-vitro study. An intraoral digital torque gauge was positioned perpendicular to the bone surface a
nd placed into the 10 mm thick bovine femoral cortical bone in the same manner as mini-implants. There were several methods used to assess the experiment’s data, including one-way ANOVA and Duncan test and analysis of variance. Results: The Tomas gave a high fracture torque value compared with GNI. GNI gave a high percentage of fracture at an apical level while Tomas gave at the middle of it. Conclusions: According to the fracture torque, the two mini-screws are accepted clinically. The design and core thickness play a major role in fracture resistance and the level of the fracture. The mini-implant format, which helps distribute force between the head and the active section of the mini-implant, is directly related to fracture resistance. Key words: Mini-screws, Fracture Torque, Anchorage, GNI Mini-Screws, Tomas Mini-Screws, Cortical bone