Lima Filho Roberto M A, de Oliveira Ruellas Antonio Carlos
Am J Orthod Dentofacial Orthop. 2008 Sep;134(3):383-8. doi: 10.1016/j.ajodo.2006.09.071.
In this study, we evaluated the long-term maxillary changes in skeletal Class II patients who had slow and rapid palatal expansion.
The sample consisted of 70 patients divided in 2 groups: 1 group was treated with cervical headgear with expanded inner bow (CHG) and the other with a Haas-type rapid palatal expansion appliance with cervical headgear (RPE-CHG). Data were collected in the molar and canine regions for basal width, alveolar width, and palatal depth at pretreatment (T1), posttreatment (T2), and postretention (T3). The Student paired t test was used to compare data and independent averages between phases.
In both groups, from T1 to T2, there were significant increases in basal width, alveolar width, and palatal depth for the molar region; in the canine region, there was a significant increase only in the alveolar width. From T2 to T3, no significant changes were found for basal and alveolar widths in both groups and regions, but a significant increase was seen in palatal depth in the molar region in the RPE-CHG group.
Slow and rapid palatal expansion can expand the maxillae and the maxillary teeth in skeletal Class II patients. Rapid palatal expansion was efficient in the treatment of skeletal Class II patients with severe transverse maxillary discrepancy. Skeletal Class II correction with slow and rapid palatal expansion produced long-term stability (10 years after orthodontic treatment).
在本研究中，我们评估了接受慢速和快速腭扩展治疗的骨性II类患者的上颌骨长期变化情况。
样本包括70例患者，分为两组：一组采用带扩弓内弓的颈牵引矫治器（CHG）进行治疗，另一组采用带颈牵引矫治器的哈斯式快速腭扩展矫治器（RPE-CHG）进行治疗。在治疗前（T1）、治疗后（T2）和保持后（T3），收集磨牙区和尖牙区的基骨宽度、牙槽骨宽度和腭深度数据。采用配对t检验比较各阶段的数据及独立均值。
两组患者从T1到T2，磨牙区的基骨宽度、牙槽骨宽度和腭深度均显著增加；在尖牙区，仅牙槽骨宽度显著增加。从T2到T3，两组及各区域的基骨宽度和牙槽骨宽度均无显著变化，但RPE-CHG组磨牙区的腭深度显著增加。
慢速和快速腭扩展均可使骨性II类患者的上颌骨和上颌牙齿得到扩展。快速腭扩展在治疗伴有严重上颌横向差异的骨性II类患者方面是有效的。采用慢速和快速腭扩展进行骨性II类错牙合矫治可产生长期稳定性（正畸治疗后10年）。
