Orthodontic Correction of Severe Gummy Smile in Class II Division 1 Malocclusion: A Case Report

Authors

Yu-Jen Hsu, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University Hospital
Sheng-Chin Lin, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University Hospital
Wen-Pei Wong, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University Hospital
Emily Yi-Min Liu, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University Hospital
Pi-Huei Liu, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University Hospital
Jenny Zwei-Chieng Chang, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University Hospital
Yi-Jane Chen, Division of Orthodontics and Dentofacial Orthopedics, Department of Dentistry, National Taiwan University HospitalFollow

Abstract

Class II division 1 malocclusion with deepbite and gummy smile can be treated in several ways. Adequate intrusion and retraction of maxillary incisors may improve the smiling appearance as well as the facial profile. However, anterior torque control can be challenging. Herein, we report a patient with 5 mm gummy smile, where the final esthetic improvement was achieved by combined use of posterior and anterior miniscrews. The 19-year-old women presented with lip protrusion, convex profile, retrusive chin, excessive gingival display, and a Class II division 1 malocclusion with mild crowding in the upper and lower dentition (1~2 mm). Cephalometric analysis showed the dental compensation to the Class II skeletal pattern with mandibular retrusion (ANB = 7.5°, MPA = 42°, U1-SN = 99°, L1-MP = 99°). The treatment plan included single arch extraction and installation of 3 miniscrews as bony anchorage. The maxillary first premolars were extracted for anterior teeth retraction and overjet correction. Two miniscrews were placed at the infrazygomatic crest of maxilla and one at the cortical bone sub-apical to maxillary incisors for retraction, intrusion, and torque control of anterior teeth. Furthermore, Class III elastics were used to prevent labial flaring of mandibular incisors. Gummy smile was obviously improved and stable occlusal relationship were established after treatment. The total treatment duration was 20 months. The cephalometric analysis showed significant intrusion and retraction of maxillary incisors as well as a slight counterclockwise rotation of mandible. This case demonstrated that the combined use of posterior and anterior miniscrews could be an effective procedure for torque control and genius intrusion of maxillary incisors in the treatment of severe dentoalveolar protrusion and gummy smile.

Recommended Citation

Hsu, Yu-Jen; Lin, Sheng-Chin; Wong, Wen-Pei; Liu, Emily Yi-Min; Liu, Pi-Huei; Chang, Jenny Zwei-Chieng; and Chen, Yi-Jane (2017) "Orthodontic Correction of Severe Gummy Smile in Class II Division 1 Malocclusion: A Case Report," Taiwanese Journal of Orthodontics: Vol. 28: Iss. 1, Article 7.
https://doi.org/10.30036/TJO.201701_28(1_2).0007
Available at: https://www.tjo.org.tw/tjo/vol28/iss1/7

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