The rhino-maxillary complex links neuro-cranium and splancno-cranium. This complex has an intramembranous growth. The dislocation in
the space takes place through two processes: sutural stress and periosteal remodeling.
The Nitanium Palatal Expander (NPE-2) performs a slow and continuous force on maxillary sutures together with the disto-rotation of the first molar.
The aim of this work is to compare the traditional expansion with Rapid Expansion Protocol (REP) with the NPE-2.
Effective orthopedic and dental growth were present both in NPE-2 and REP methods. The front width was found to be of high statistical significance (<0,0001****) with differential pre-post (Δ) REP with average data of 4,25 mm and likewise Δ NPE-2 with average data of
In the same way the post width turned out to be of high statistical significance (<0,0001****) with Δ REP with average data of 4,15 mm and likewise Δ NPE-2 with average data of 4,44 mm.
The palatal eight instead resulted a slight and non-significant contraction with Δ REP (mean -0.38 mm) and Δ NPE-2 (mean -0.01 mm).
Thirty-six patients were enrolled in this study. All patients had a transversal defect, before undergoing the treatment all the patients and their parents were informed about therapy and subscribed an informed consent.
Eighteen patients underwent a treatment of expansion with NPE-2 and an equal number with REP, preferring patients treated with NPE-2 in the case of simultaneous disto-rotation of the upper first molars.
Analysis of models were performed on digital scans
(3-Shape Trios®) before and immediately after treatment.
The expansion of the rhino-maxillary complex is a common orthopedic-orthodontic practice in transversal deficit in growth.
The use of REP and NPE-2 in this study, showed that these two methods are equally effective in solving this defect, choosing the NPE-2 method when the molar needs to be disto-rotation or not.
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Comparing the differentials (Δ) of two methods, NPE-2 and REP, no statistically significant variables were found.