Edition V13N05 | Year 2008 | Editorial Orthodontic Insight | Pages 20 to 27
Convergent ideas concerning mini-implants. Certain ideas concerning the use of mini-implants for skeletal anchorage in orthodontic practice seem to have achieved widespread consensus1- 43, such as: 1. Mini-implants represent a major breakthrough in the clinical orthodontic practice of the last 10 years, arguably the most relevant for contemporary Orthodontics. 2. The anchorage afforded by mini-implants can be utilized immediately following their implantation or up to 15 days later. The amount of initial force must be somewhere between 150 and 200 g, preferably measured with the help of a tension gauge to avoid overload. Gradually, this force can be increased up to 350 g by taking into consideration bone quality factors, such as cortical thickness and bone density. 3. The mini-implant action mechanism results from the mechanical interlocking of its metal structure in cortical and dense bone and is not based on the concept of osseointegration. The shape and length of the cutting threads are instrumental in mini-implant placement. Resistance to fracture forces can be enhanced by means of a tapered design and self-drilling threads. These features help to dissipate compression forces from bone structures adjacent to the mini-implant during insertion.