Does mini-implant-supported rapid maxillary expansion cause less root resorption than traditional approaches? A...

Area of Science:

• Orthodontics
• Dental Materials Science

Background:

• Rapid maxillary expansion (RME) is a common orthodontic procedure.
• Root resorption is a potential side effect of RME, necessitating investigation into appliance-specific effects.

Purpose of the Study:

• To compare the volumetric, quantitative, and localization aspects of root resorption in maxillary first premolars across four distinct RME appliances.
• To evaluate the efficacy of a mini-implant-supported hybrid RME appliance versus conventional RME appliances in minimizing root resorption.

Main Methods:

• Micro-computed tomography (micro-CT) was employed to scan maxillary first premolars from 20 patients undergoing RME.
• Patients were stratified into four groups based on the RME appliance used: hybrid, Hyrax, acrylic-bonded, and full-coverage.
• Root resorption craters were quantified and localized using CTAn software, with statistical analysis performed using Kruskal-Wallis and Mann-Whitney U tests.

Main Results:

• The hybrid RME appliance demonstrated significantly lower root resorption volume and fewer craters compared to other appliances (p < 0.001).
• No significant differences in overall root resorption were observed among the Hyrax, acrylic-bonded, and full-coverage RME groups (p > 0.05).
• Buccal root surfaces exhibited greater resorption than lingual surfaces in all groups, except for the hybrid appliance group.

Conclusions:

• All evaluated rapid maxillary expansion appliances induce root resorption, predominantly on the buccal aspect of the maxillary first premolars.
• The mini-implant-supported hybrid RME appliance appears to be a more conservative option, resulting in reduced root resorption compared to conventional RME appliances.