Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
9992995 | American Journal of Orthodontics and Dentofacial Orthopedics | 2005 | 10 Pages |
Abstract
Purpose: Banding a rapid palatal expansion (RPE) appliance to the 2 first molars has been proposed as an equivalent to the conventional 4-band RPE appliance. However, the dentoskeletal response to this treatment has not been evaluated. Material: Twenty-eight subjects (aged 8-20 years) who required maxillary expansion were matched by age and randomly assigned to either a 2-band or a 4-band RPE group. Skeletal and dental responses were measured from standardized anteroposterior cephalometric and occlusal radiographs and dental casts before treatment (T1), at the end of expansion (T2), and at 1 year postexpansion (T3). Results: At T2, suture expansion was 2.5 times greater and arch perimeter was 6-fold larger in the 4-band than in the 2-band group. Both appliances displayed the typical “V” expansion of the suture and “reverse V” expansion of the dental arch. At T3, remineralization reduced the suture opening by 75%, but 95% to 99% of the dental reaction was maintained. The 2-band group demonstrated a significant inverse age-dependent correlation (r = â0.795), with treatment failure beyond 12 years of age, whereas the 4-band group was age-independent. Conclusions: The greater the skeletal resistance, the smaller the sutural response but the greater the dental response to RPE therapy. Four-band RPE is indicated when severe anterior crowding is accompanied by a tapered arch form, and 2-band RPE is recommended in the mixed dentition when mild crowding occurs with posterior constriction.
Related Topics
Health Sciences
Medicine and Dentistry
Dentistry, Oral Surgery and Medicine
Authors
Moshe Davidovitch, Stathis Efstathiou, Ofer Sarne, Alexander D. Vardimon,