关键词: 微型种植体, 支抗, 伸长磨牙, 压低, miniscrews, orthodontic anchorage, overerrupted molar intrusion, intrusion

Abstract: Objective To study the efficiency of connected miniscrews as anchorage to lower molar intrusion . Methods 3 patients with overerrupted lower molars were selected. Two miniscrews, 1.6 mm in diameter, 9 mm in length, were placed buccully in the interradicular areas between second premolar and first premolar. Two buccally placed miniscrews were connected by 2 straight 0.48 mm×0.64 mm orthodontic stainless steel archwires were welded. The distal ends of the wires were bent to form a hook stretching to the buccal lingual side of the molars.. A elastic generating 1N force was connected to the lingual and buccal hooks to intrude the overerrupted molar. Results All the implatation was successful and there was no loosening in the treatment. After 5 months' treatment, the overerupted lower posterior molars were lowered . Conclusion Connected miniscrews can be effective anchorage to lower overerupted molars．