Evaluation of Changes in Lip Closing Force After Surgically Assisted Rapid Maxillary Expansion

Abstract

The present study demonstrated that, following surgically assisted rapid palatal expansion, both the maximum and the minimum lip closing force increases had a tendency to revert to their initial values 6 months after surgery.

Changes in maximum lip-closing force after extraction and nonextraction orthodontic treatments

“…Thus, MLF has been used as a functional indicator for the lip or perioral muscles in studies on the effects of the lips on the craniofacial structure or studies involving measurement of the lip strength after surgical-orthodontic treatment. [16][17][18]20 The lip force can be affected by various factors, including age, gender, and skeletal and dental patterns; 17,18,[21][22][23][24] therefore, we only included women with Class I and mild Class II malocclusion in the present study. At T0, the extraction and nonextraction groups exhibited no significant differences in the vertical and sagittal skeletal measurements (Table 1), which indicated a similar skeletal pattern in the two groups.…”

“…Orthodontic extraction in patients with Class II division 1 (II/1) malocclusion or bialveolar protrusion can help in relieving the lip protrusion by facilitating retraction of the maxillary and mandibular incisors, thus resolving the lip incompetence and improving the facial profile. 14,15 In addition to the enhancement of facial esthetics, an improvement in the lip-closing force after surgical-orthodontic approaches, such as orthognathic surgery 16,17 and surgically assisted rapid palatal expansion 18 was recently reported. Considering the previous studies, there have been few studies on the changes in the lip-closing force after orthodontic treatment and their correlation with dentofacial and dental arch dimensional changes.…”