Ingervall B, Thüer U
Department of Orthodontics, University of Bern, Switzerland.
Eur J Orthod. 1998 Oct;20(5):525-34. doi: 10.1093/ejo/20.5.525.
The pressures from the lower lip on the lower incisors were measured at the midline between the central incisors and between the left lateral incisor and canine. The measurements were made with the lip at rest and during swallowing of water in 24 boys and 40 girls aged 9-15 years. The children were divided into four groups, two treated with a lip bumper with and without an oral shield, and two with a lingual arch with and without springs for proclination of the lower incisors. Recordings of the pressures were made before the start of the treatment, and 3 and 8 months after the use of the appliance, as well as 4 months after the removal of the lip bumper or lingual arch. The treatment with a lip bumper did not change the pressure from the lip on the lower incisors at rest. The pressure at the midline during swallowing was also unaffected by the lip bumper therapy, but the pressure between the lateral incisor and canine increased. Thus, lip bumper therapy did not lead to decreased pressure from the lip on the incisors. Proclination of the lower incisors with a lingual arch resulted in an increase of the pressure from the lip at rest. Thus, no adaptation of the lower lip to the proclination occurred. After relapse of the proclination the pressure from the lip decreased to a value no different from that before the start of the treatment.
在下颌中切牙之间的中线以及左外侧切牙与尖牙之间测量下唇对下颌切牙的压力。对24名男孩和40名9至15岁女孩在嘴唇静止时以及吞咽水时进行测量。将这些儿童分为四组，两组使用带或不带口盾的唇挡进行治疗，另外两组使用带或不带用于使下颌切牙前倾的弹簧的舌弓进行治疗。在治疗开始前、使用矫治器3个月和8个月后以及拆除唇挡或舌弓4个月后记录压力。使用唇挡治疗不会改变嘴唇在静止时对下颌切牙的压力。吞咽时中线处的压力也不受唇挡治疗的影响，但外侧切牙与尖牙之间的压力增加。因此，唇挡治疗不会导致嘴唇对切牙的压力降低。使用舌弓使下颌切牙前倾会导致嘴唇在静止时的压力增加。因此，下唇并未因前倾而发生适应性变化。切牙前倾复发后，嘴唇的压力降至与治疗开始前无差异的值。
