Tooth movement in orthodontics occurs through remodeling of the alveolar bone. Frontal resorption involves direct resorption of the bone adjacent to the moving tooth, allowing for smooth and controlled displacement. This process preserves the integrity of the bone and periodontal ligament, resulting in more physiological and efficient tooth movement. In contrast, undermining resorption involves resorption away from the bone surface, causing delayed and less favorable movement. Hence, frontal resorption is preferred for predictable orthodontic tooth movement with minimal tissue damage.

Reference: Graber’s Orthodontics, 7th Edition.