Changes in pharyngeal airway dimensions and hyoid bone position after maxillary protraction with different alternate rapid maxillary expansion and construction protocols: A prospective clinical study

Abstract

Objective: To evaluate the changes in pharyngeal airway dimensions and the position of the hyoid bone after maxillary protraction with different alternate rapid maxillary expansion and construction (Alt-RAMEC) protocols in patients with skeletal class III malocclusion as a result of maxillary retrusion. Material and Methods: The patients with skeletal class III malocclusions were consecutively divided into two groups. Group 1 consisted of 17 patients (11 boys and 6 girls, mean age 11.31 6 1.71 years) who had the Alt-RAMEC protocol for 5 weeks, and group 2 consisted of 17 patients (10 boys and 7 girls, mean age 11.64 6 1.24 years) who had the Alt-RAMEC procedure for 9 weeks. In this study, 4 angular and 13 linear measurements were performed to evaluate the skeletal and pharyngeal airway changes that occurred after maxillary protraction. Results: A significant increase in the maxillary growth, inhabitation of mandibular growth, and clockwise rotation of the mandible caused the improvement of the maxillo-mandibular relationship in both groups. Those changes caused a significant increase in the upper pharyngeal airway dimension (P , .01) and affected the vertical position of the hyoid bone in both groups (P , .05 and P , .01, respectively). However, changes that occurred in both groups were found to be similar for all airway variables (P . .05). Conclusion: Upper pharyngeal dimension and vertical position of the hyoid bone were affected by the maxillary protraction with different Alt-RAMEC protocols. There were no statistically significant differences between the groups. (Angle Orthod. 2017;87:519-525)

Comparison of the effects of rapid maxillary expansion and alternate rapid maxillary expansion and constriction protocols followed by facemask therapy

“…Consequently, no significant change was observed in the palatal plane angle. Accordingly, all measurements related to the anterior and posterior face heights increased in agreement with the findings of previous studies 51317…”

“…In contrast, Kaya et al5 protracted the maxilla by using miniplates after the Alt-RAMEC protocol, and they reported a 2-mm forward movement of the A point. In the Alt-RAMEC/FM study of Celikoglu and Buyukcavus,13 a significant increase of 3.34° in the SNA angle was reported. However, only Liou and Tsai4 used a double-hinged expander as in our study.…”

“…Moreover, the effects of the Alt-RAMEC/FM protocol on airway changes have not been evaluated thoroughly. Only Celikoglu and Buyukcavus13 examined PA changes two-dimensionally after the Alt-RAMEC/FM protocol and reported an increase in upper PA dimensions. However, the expansion device used in that study contained a Hyrax screw and was activated twice a day, which was different from the routine Alt-RAMEC protocol introduced by Liou and Tsai 4…”

A retrospective evaluation of conventional rapid maxillary expansion versus alternate rapid maxillary expansion and constriction protocol combined with protraction headgear in the management of developing skeletal Class III malocclusion

“…The posterior rotation of the mandible and the increase of anterior face height could be due to a combination of maxillary vertical movement, maxillary molars extrusion, and chin cup effect of reverse pull headgear. Celikoglu and Buyukcavus[ 16 ] in their study with two different Alt-RAMEC protocols reported similar findings of a significant increase in the maxillary growth, inhibition of mandibular growth, and clockwise rotation of the mandible, leading to an improvement of the maxillomandibular relationship in both groups.…”

Comparison of treatment effects of different maxillary protraction methods in skeletal class III patients

“…Researchers have used the face mask in various combinations over the years. 3,27,28 Temporary anchorage devices and maxillary protraction applications with direct bone support are recently popular to reduce dentoalveolar effects and increase the skeletal effect. 23,24 There are also applications that perform maxillary protraction with the use of direct miniscrews and inter-miniplates with Class III elastics, as well as successful studies that can be constructed from direct skeletal anchorage using a face mask.…”