Effect of the length of orthodontic mini-screw implants on their long-term stability: a prospective study

To analyze the influence of the length of temporary intraoral skeletal anchorage devices (TISAD/TAD) on their long-term stability in the mandible in a homogenous group of patients. A group of generally healthy patients of the same gender (female) and with a statistically insignificant age difference (20-29 years) highly homogenous with respect to known factors affecting the success rate of TISAD/TAD was evaluated. One type of TISAD/TAD was applied (6- or 8-mm long). Each patient received both 6- and 8-mm-long TISAD/TAD in randomly selected mandibular quadrants: left or right. The long-term success rate of TISAD/TAD was analyzed. The 8-mm orthodontic mini-screw implants were significantly more stable than the 6-mm ones in the analyzed group. The length of the TISAD/TAD may be one of the factors that can affect the long-term success rate in the mandibles of 20- to 29-year-old women.