Minimum required length of orthodontic microimplant: a numerical simulation and clinical validation.

Introduction: This study aimed to determine the minimum required length of microimplants (MIs) to prevent excessive micromotion during MI healing that can lead to MI failure.

Methods: Hypothesizing that the implantation depth of MI in cancellous bone (ID) is the key to the control of micromotion during MI healing, we numerically investigated the minimum ID required to maintain MI micromotion to below the threshold (30 μm) that would threaten MI survival. Twenty MI and bone models were built using MIs of 4 lengths and bone specimens with 5 different cortical bone thicknesses to create ID in the 0.