Comparative evaluation of dental, dentoalveolar and skeletal effects of slow maxillary expansion using Jackscrew, Quadhelix and Niti palatal expander2 on a finite element model of a young skull

Introduction: Slow expansion is a routine procedure for space gaining in Orthodontics. Jack Screw, Quadhelix and NiTi palatal expander-2 are commonly used slow expansion devices with a varied degree of dental and skeletal effects. Finite element method is a well- established technique to analyze stress and deformation in the craniofacial region in three dimensions after application of orthodontic forces. This study was aimed to evaluate and compare the dental, dento-alveolar and skeletal effects of the three slow expansion devices: Jackscrew, Quad helix and NiTi expander-2 on a young maxillary bone using a finite element model. Materials and Method: The 3D finite element model was developed after scanning a dried human skull of mixed dentition with white light scanner. The mechanical properties of the teeth, bone and sutures were defined for the analytical model and subjected to forces by three expansion devices to compare their dental, dento-alveolar and skeletal effects. Results: All the three expansion devices show significant difference in overall stress distribution and deformation in X and Y axis whereas equal efficiency in Z-axis. All the three devices showed significant differences in dental, dento-alveolar and skeletal effects where, Jackscrew showed highest deformation in X axis in the dental region and highest deformation in Y and Z axis in the dento-alveolar region. Conclusion: The highest values of stress and strain are shown by Jackscrew, followed by Quadhelix and lastly by NiTi palatal expander-2 where Quadhelix and NiTi expander-2 showed almost similar performance.