Shah Rupal, Sharif Mohammad O, Gill Daljit S
1 Department of Orthodontics, Eastman Dental Hospital, London, UK.
2 Department of Orthodontics, UCL Eastman Dental Institute, London, UK.
J Orthod. 2019 Mar;46(1):56-62. doi: 10.1177/1465312518820328. Epub 2019 Jan 23.
Patients presenting with severe hypodontia can be challenging to manage. They often present with significant spaces within the dental arches and the lack of permanent teeth can make anchorage control difficult. This case report demonstrates a novel technique for diastema closure in a 14-year-old with severe hypodontia. The technique allows maintenance of root parallelism during space closure in cases with reduced anchorage support. The treatment plan was agreed on a multidisciplinary hypodontia clinic and involved an upper sectional fixed orthodontic appliance to close a 7-mm midline diastema aiding subsequent partial denture provision. Treatment commenced by bonding upper primary canines and central incisors. However, attempting space closure on a 0.019 × 0.025-inch stainless-steel working archwire resulted in tipping of the incisor crowns. Two brackets were therefore placed on the labial surface of each central incisor (one incisal and one gingival). Subsequently two stainless steel working archwires and elastomeric chain were used for diastema closure. This four-bracket system provided superior control allowing space closure by bodily tooth movement. Excellent root parallelism was achieved with this innovative technique.
患有严重牙列缺损的患者治疗起来颇具挑战。他们的牙弓内常常存在明显间隙，且恒牙缺失会使支抗控制变得困难。本病例报告展示了一种为一名14岁严重牙列缺损患者关闭牙间隙的新技术。该技术在支抗支持减少的情况下，能在关闭间隙过程中保持牙根平行。治疗方案在多学科牙列缺损诊所确定，包括使用上颌局部固定正畸矫治器关闭7毫米的中线牙间隙，以利于后续局部义齿修复。治疗开始时，粘结上颌乳尖牙和中切牙。然而，在0.019×0.025英寸的不锈钢工作弓丝上尝试关闭间隙导致切牙冠倾斜。因此，在每个中切牙唇面放置两个托槽（一个切端和一个龈端）。随后使用两根不锈钢工作弓丝和弹力链关闭牙间隙。这种四托槽系统提供了更好的控制，可通过牙齿整体移动关闭间隙。采用这种创新技术实现了极佳的牙根平行。
