Does the Alternate Rapid Maxillary Expansion-Constriction/Reverse Headgear Therapy Enhance Pharyngeal Airway Dimensions?

Abstract

Objective:The enhanced effect of maxillary protraction following the Alternate Rapid Maxillary Expansion-Constriction/Reverse Headgear (AltRAMEC/RH) protocol over the Rapid Maxillary Expansion/Reverse Headgear (RME/RH) protocol has been well documented. However, it is not known if the airway dimensions also follow a similar enhancement. This retrospective cohort study therefore aims to compare dimensional changes in the pharyngeal airway after maxillary protraction following RME/RH, versus AltRAMEC/RH.Methods: Pre- and post-treatment lateral cephalograms of 46 skeletal Class III patients with maxillary retrusion, who had undergone maxillary protraction using the AltRAMEC/RH or RME/RH protocol were compared for 20 dentoskeletal and airway variables. The waiting period of 6-8 months before initiating treatment served as the control period. The results were statistically evaluated using the paired t-test, the independent t-test, and the intraclass correlation coefficient.Results: The nasopharyngeal airway indicators in the AltRAMEC/RH group (PNS-ad1, PNS-ad2, UPD) showed a statistically significant mean increase of 2.09 mm, 2.74 mm, and 1.30 mm respectively. This was significantly more pronounced than the RME/RH group (P .001).Conclusions: The AltRAMEC/RH protocol produced more significant improvement in the nasopharyngeal airway dimensions as compared to the RME/RH protocol. The changes in the oropharyngeal airway were insignificant with both the protocols.

Keywords

• skeletal class iii
• maxillary protraction
• pharyngeal airway
• nasopharynx
• rapid maxillary expansion