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Skeletal changes of maxillary protraction without rapid maxillary expansion
Dong-Yul Lee1, Eun-Soo Kim, Yong-Kyu Lim
1Department of Orthodontics, Korea University, Seoul, South Korea.
The Angle Orthodontist
|May 21, 2010
Summary
Face mask therapy without rapid maxillary expansion (RME) showed similar long-term skeletal effects whether started in primary or mixed dentition. Early treatment response and relapse were greater in the primary dentition group.
Area of Science:
- Orthodontics
- Craniofacial development
- Pediatric dentistry
Background:
- Class III malocclusion often requires early intervention.
- Maxillary hypoplasia is a key feature of Class III malocclusion.
- Face mask therapy is a common treatment for maxillary retrusion.
Purpose of the Study:
- To compare the effectiveness of face mask therapy without rapid maxillary expansion (RME) in children at different early dental stages.
- To evaluate skeletal changes and treatment outcomes based on the timing of intervention.
Main Methods:
- Forty-nine Class III children were divided into primary and mixed dentition groups.
- Treatment involved face mask therapy without RME.
- Lateral cephalograms were analyzed at three time points: pre-treatment, end of treatment, and post-treatment follow-up.
Main Results:
- The primary dentition group initially showed a greater response to maxillary protraction.
- However, the primary dentition group also exhibited a higher relapse tendency.
- No significant long-term differences in skeletal changes were observed between the groups.
Conclusions:
- Face mask therapy without RME yields comparable skeletal outcomes regardless of whether it is initiated in primary or mixed dentition.
- The findings suggest that treatment can be effectively initiated in the early to mid-mixed dentition period.
- This timing may offer similar benefits to early primary dentition treatment while potentially simplifying management.
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