Intrusion Mechanics

Intrusion Mechanics is a fundamental aspect of orthodontic treatment aimed at moving teeth vertically into the alveolar bone with minimal adverse effects on surrounding structures. It is commonly employed in the correction of deep bite malocclusions, management of supra-erupted teeth, reduction of excessive gingival display, and improvement of occlusal relationships. Successful intrusion requires the application of light, continuous forces directed close to the tooth's center of resistance to achieve controlled tooth movement while minimizing root resorption and anchorage loss.The biomechanics of intrusion involve a thorough understanding of force systems, moments, and anchorage requirements. Various approaches have been developed, including continuous archwire mechanics, utility arches, segmented arch techniques, intrusion arches, and skeletal anchorage systems such as temporary anchorage devices (TADs). Recent advances in orthodontics have enhanced the predictability of intrusion through improved appliance designs and anchorage control methods.