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Esthetic Improvement through Orthodontic Treatment Involving Extraction: Use of Orthodontic Anchor Screws
1Department of Orthodontics, Tokyo Dental College.
Abstract:
Here, we report two cases of dental bimaxillary protrusion in which orthodontic anchor screws were used to improve the esthetics of the mouth and lips and facilitate complete closure of the mouth. Case 1 was a woman with dental maxillary protrusion and constriction of the dental arches, with the main complaint of protrusion of the lips and mandibular crowding. The maxillary and mandibular dental arches were first widened and traction applied to the maxilla via orthodontic anchor screws. The maxillary incisors were retracted 10 mm and the mandibular incisors 3 mm, resulting in upper lip retraction of 3 mm and bottom lip retraction of 5 mm with respect to the E-line. The nasolabial angle increased to 20°, and the inter-vermilion angle, which indicates the thickness of the vermillion, decreased to 20°, improving esthetics by reducing the thickness of the lips. Case 2 was a woman with bimaxillary dental protrusion, with the chief complaint of protruding lips and a gummy smile. Orthodontic anchor screws were used to achieve posterior traction and intrusion in the maxillary incisor region to improve the gummy smile. The maxillary incisors were retracted 9 mm and the mandibular incisors 8 mm. In the soft tissues, this yielded upper lip retraction of 3 mm and bottom lip retraction of 4 mm with respect to the E-line. The nasolabial angle increased to 10° and the inter-vermilion angle decreased to 30°, improving esthetics by reducing the thickness of the lips. The gummy smile was also improved, with 4 mm intrusion of the maxillary incisors. Increased ease in closing of the mouth was also a major factor in patient satisfaction with the results of orthodontic treatment.
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