A Treatment Of Using Mini-screw Implants For A High Angle Skeletal Class ? Patient With Gummy Smile

Objective:The purpose of this study was to evaluate the clinical treatment effect of mini-screw implants anchorage on a high angle skeletal Class ? patient with gummy smile.Methed : A high angle skeletal Class ? patient with lips-incompetent and gummy smile enroll to Dalian Stomatological Hospital's Orthodontics apartment in 2013 was selected.The patient was 13 years old female.She had mouth breathing for five years.Extraoral examination showed a convex profile with mandibular deficiency and slight maxillary protrusion.Nasolabial and mentolabial sulcus were acute.Lips were Incompetent along with severe gummy smile.Intraoral examination displayed Class?molar relationship on both sides.The maxillary arch was pointed circular shape while the mandibular arch was square shaped which also showed slight crowding in the anterior region.A severe deep bite,an overjet and anterior lip inclination were noted.The maxillary first premolars and the mandibular second premolars were extracted,and use mini-screw implants anchorage for retraction and intrusion.when the maxillary anterior teeth axis were normal,the mini-screw implants were inserted buccally between upper central and lateral incisors on both sides for intruding upper incisors together with fixed appliance.Clinical records and cephalometric analysis were done to evaluate pre-treatment and post-treatment changes in dentoalveolar structures and soft tissue.Result:Total treatment duration was 26 months.A normal overjet and overbite were achieved.The upper and lower dental arches were well aligned,and Class I molar relationship was achieved.The strain of the mentalis muscle became more relaxed.The facial profile was significantly improved.The post-treatment panoramic radiograph confirmed that no additional root resorption occurred in the intruded upper incisor region,and the root paralleling was achieved,the bilateral condylar position were normal,and no obvious change was found.Comparing pre-treatment and post-treatment,it showed that:(1)SNB was slightly increased,and ANB was reduced to5.4 °.(2)U1/SN was decreased by 28.6 °,upper incisors were intrusted obviously.U1-NA distance decreases by 8.3mm and U1/NA was reduced to 26.4°.Lower incisors were lip inclination,L1-NB distance increased by 0.9mm;Ll/NB add to4°.(3)MP/SN decreased by 2.6°as the mandible rotated inverse clockwise.With the height of facial lower 1 / 3 decreased,The profile was improved and relationship of lip and chin tends to coordinate.Conclusion: For a high angle skeletal Class?patient with deep overbite,overjet and gummy smile through the application of mini-screw implant anchorage,a Class I occlusion relationship,coordinated profile and charming smile could be achieved.