Antero-posterior lingual sliding retraction system for orthodontic correction of hyperdivergent Class II protrusion

BACKGROUND This report introduces a lingual bonded retraction system (Kinematics of Lingual Bar on Non-Paralleling Technique, KILBON) for efficient sliding mechanics combined with vertical control of the anterior and posterior teeth, which is suitable for Class II hyperdivergent patients. METHODS Design and biomechanics of the KILBON System were described. Two adults with hyperdivergent class II malocclusion were treated with the KILBON system and temporary skeletal anchorage devices (TSADs) on the palate. The first patient was treated with conventional KILBON system on the upper arch and detailed with lingual appliances. The second patient showed the modified design of the KILBON when applied to a low palatal vault. RESULTS A large amount of intrusion and retraction of the anterior teeth and simultaneous intrusion of the posterior segment were achieved in short treatment time. Concomitant counterclockwise rotation of the mandible improved the esthetic profile. Periodontal support without dehiscence or bone loss was confirmed on anterior region in spite of large amount of retraction. CONCLUSIONS This report presented a lingual retraction system that provides simple and effective vertical and sagittal control of both anterior and posterior teeth. The biomechanics are dependable for correcting a dentoalveolar protrusion in a patient with Class II hyperdivergent skeletal pattern.