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Published on: February 23, 2024
Tricortical versus bicortical anchorage in a double-screw tandem skeletal expander and a single-screw maxillary
Luca Brucculeri1, Federica Pellitteri1, Alfredo Salvatore Monterossi1
1Postgraduate School of Orthodontics, University of Ferrara, Ferrara, Italy.
Objective:
This study aims to employ finite element method (FEM) analysis to compare the differences between bicortical and tricortical anchorage of the posterior miniscrews in a single-screw miniscrew-assisted rapid palatal expansion (MARPE) and a double-screw tandem skeletal expander (TSE) under open and closed suture conditions.
Methods:
A cone beam computed tomography of the human skull of a 21.5-year-old female was utilized as a model for creating a FEM analysis. Simulations involved the insertion of four palatal miniscrews: two anterior ones with bicortical anchorage and two posterior ones (one with bicortical and another with tricortical anchorage), under open and closed suture conditions in a single-screw MARPE and double-screw TSE, resulting in a total of eight different simulation configurations. Evaluation parameters include total deformation (mm), Von Mises stress (MPa), and strain for each miniscrew body.
Results:
Tricortical anchorage of the posterior miniscrews provides greater anchorage, higher stress, and deformation on the anterior miniscrews in single-screw MARPE. Tricortical anchorage combined with a double-screw TSE promotes a more even distribution of force and stress on miniscrews under open suture conditions, leading to a parallel midpalatal suture opening along its entire length and height.
Conclusions:
FEM analysis revealed favorable midpalatal suture opening with equal force distribution and less stress when posterior tricortical anchorage in conjunction with double-screw TSE is applied.
