Jena Ashok Kumar, Anusuya Venkatachalapathy, Sharan Jitendra
Department of Dentistry, All India Institute of Medical Sciences, Sijua, Bhubaneswar, Odisha, India.
Turk J Orthod. 2022 Dec;35(4):248-254. doi: 10.5152/TurkJOrthod.2022.21157.
To evaluate the effects of large retraction of incisors on the adaptive changes in the posterior pharyngeal wall and soft palate during comprehensive orthodontic treatment.
Twenty-seven females with Class I mild crowding or spacing who required non-extraction treatment (group I) and 34 females with Class I bimaxillary dentoalveolar protrusion who required all first premolars extraction for the retraction of their incisors (group II) were included in the study. The effects of non-extraction and incisor retraction following all first premolars extraction orthodontic treatment on the sagittal dimensions of pharyngeal airway passage and posterior pharyngeal wall thickness were evaluated from pre- and post-treatment cephalograms.
The dimensions of pharyngeal airway passage were comparable among the groups. The length of the soft palate increased (P < .01) and the thickness of the soft palate decreased (P < .01) following retraction of incisors, and the difference between the groups was significant (P < .05). The posterior pharyngeal wall thickness was reduced significantly at PPWT2 (P < .05), PPWT3 (P < .001), PPWT4 (P < .001), PPWT5 (P < .001), and PPWT6 (P < .01) regions following retraction of the incisors, and the difference between the groups was statistically highly significant.
The large retraction of incisors during comprehensive orthodontic treatment in Class I bimaxillary dentoalveolar protrusion malocclusion subjects did not affect the sagittal dimensions of pharyngeal airway passage, but the thickness of the posterior pharyngeal wall reduced significantly as an adaptation to maintain the patency of the upper airway.
评估在综合正畸治疗过程中，切牙大幅后移对咽后壁和软腭适应性变化的影响。
本研究纳入了27名需要非拔牙治疗的I类轻度牙列拥挤或牙列间隙女性患者（I组）和34名需要拔除双侧第一前磨牙以内收切牙的I类双颌牙性前突女性患者（II组）。通过治疗前后的头颅侧位片，评估非拔牙治疗及拔除双侧第一前磨牙正畸治疗内收切牙后对咽气道矢状径及咽后壁厚度的影响。
各组间咽气道径的大小具有可比性。切牙内收后软腭长度增加（P <.01），软腭厚度减小（P <.01），且两组间差异有统计学意义（P <.05）。切牙内收后，咽后壁厚度在PPWT2（P <.05）、PPWT3（P <.001）、PPWT4（P <.001）、PPWT5（P <.001）和PPWT6（P <.01）区域显著降低，且两组间差异具有高度统计学意义。
在I类双颌牙性前突错牙合畸形患者的综合正畸治疗过程中，切牙的大幅后移并未影响咽气道矢状径，但咽后壁厚度显著减小，作为一种适应性变化以维持上气道通畅。
