Derakhshan M, Sadowsky C
Department of Orthodontics, College of Dentistry, University of Illinois at Chicago, 801 S. Paulina St., Chicago, IL 60680, USA.
Am J Orthod Dentofacial Orthop. 2001 May;119(5):546-53. doi: 10.1067/mod.2001.112113.
A 41-year-old white woman with no particular concerns about facial esthetics was first seen with bilateral Class II molar relationship, a Class I right canine, and a Class II left canine. Overjet was 3 mm and overbite was 0.5 mm, with no incisor contact. A maxillary right premolar was missing for unknown reasons and all 4 third molars had previously been extracted. The maxillary midline was 2 mm to the right of the facial midline, and the mandibular midline was 3.5 mm to the left of the maxillary midline. There was 7 mm of crowding in the maxillary arch and 6 mm of crowding in the mandibular arch, with an increased curve of Spee. The patient had a well-positioned maxilla, a retrognathic mandible with increased convexity, a Class II denture base relationship, and a vertical facial pattern. The treatment plan consisted of extracting the maxillary left first premolar and the mandibular left central incisor. After 4 months of treatment, an open bite from second premolar to second premolar was noted. After 6 months of treatment, the patient expressed concern with her chin position and mentalis hyperactivity. It was apparent that the orthodontic treatment had resulted in molar extrusion, which the musculature was not able to withstand. Treatment continued and the case was set up for posterior maxillary impaction and mandibular advancement surgical procedures.
一名41岁的白人女性,对面部美学没有特别担忧,初诊时双侧磨牙关系为II类,右侧尖牙为I类,左侧尖牙为II类。覆盖为3mm,覆合为0.5mm,切牙无接触。上颌右侧第一前磨牙不明原因缺失,四颗第三磨牙均已拔除。上颌中线位于面部中线右侧2mm,下颌中线位于上颌中线左侧3.5mm。上颌牙弓拥挤7mm,下颌牙弓拥挤6mm,Spee曲线加深。患者上颌位置良好,下颌后缩且凸度增加,义齿基托关系为II类,面部垂直型。治疗计划包括拔除上颌左侧第一前磨牙和下颌左侧中切牙。治疗4个月后,发现从第二前磨牙到第二前磨牙出现开颌。治疗6个月后,患者对自己的下巴位置和颏肌亢进表示担忧。显然,正畸治疗导致了磨牙伸长,肌肉组织无法承受。治疗继续进行,并安排了上颌后份骨块整体上移和下颌前徙手术。