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Dento-skeletal response to three different protocols of rapid maxillary expansion in hyperdivergent growing subjects:
Manuela Mucedero1, Silvia Fanelli1, Matteo Rozzi1
1Department of Systems Medicine, University of Rome "Tor Vergata", Rome, Italy.
Background:
The aim of this study was to evaluate the dento-skeletal response in hyperdivergent growing patients comparing Rapid Maxillary Expansion (RME) using three different protocols.
Materials And Methods:
Three groups of hyperdivergent subjects treated with RME were analyzed. In 41 patients (23F, 18M) the RME was bonded on the maxillary deciduous second molars (E-RME group); in 40 patients (24F, 16M) the RME was bonded on the first permanent maxillary molars (6-RME group); in 45 patients (26F,19M) the RME was bonded on the first permanent maxillary molars with a removable mandibular Bite-Block (6-RME/BB group). Lateral cephalograms and dental casts were scanned and digitally measured before treatment (T1), at the appliance removal (T2) and at least 1 year after the appliance removal (T3). The comparison was made within the same group and between the groups. Statistical comparisons were assessed with analysis of variance multi-comparison test (*P = 0.05).
Results:
A significant increase of upper molars buccal tipping was observed in 6-RME group when compared with E-RME and 6-RME/BB groups in the short-term (T2-T1) and long-term (T3-T1); a significant intercanine width increase was observed in E-RME group at the same times. No significant differences in dentoalveolar variables were observed comparing E-RME group versus 6-RME/BB group.
Conclusions:
The E-RME protocol allows for a greater skeletal expansion and produces a lower buccal tipping of the first permanent upper molars. The use of the BB in 6-RME/BB group shows a similar attitude to the E-RME protocol then can be considered an effective therapeutic alternative.
