Introduction: The aim of this prospective controlled study was to evaluate the long-term effects of rapid maxillary expansion and facemask therapy in Class III subjects. Methods: Twenty-two subjects (9 boys, 13 girls; mean age, 9.2 years 6 1.6) with Class III disharmony were treated consecutively with rapid maxillary expansion and facemask therapy followed by fixed appliances. The patients were reevaluated at the end of the 2-phase treatment (mean age, 14.5 years 6 1.9) and then recalled about 8.5 years after the end of rapid maxillary expansion and facemask treatment (mean age, 18.7 years 6 2.1). Two groups of controls with untreated Class III malocclusion were used for statistical comparisons of the short-term and long-term intervals. Statistical comparisons were performed with the Mann-Whitney U test. Results: In the long term, no significant differences in maxillary changes were recorded, whereas the treatment group showed significantly smaller increases in mandibular protrusion. The sagittal maxillomandibular skeletal variables maintained significant improvements in the treatment group vs the control groups. Conclusions: In the long term, rapid maxillary expansion and facemask therapy led to successful outcomes in about 73% of the Class III patients. Favorable skeletal changes were mainly due to significant improvements in the sagittal position of the mandible. (Am J Orthod Dentofacial Orthop 2011;140:493-500)

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Introduction: Our aim in this prospective randomized clinical study was to assess the prevalence rate of eruption of palatally displaced canines, diagnosed at an early developmental stage with posteroanterior radiographs and consequently treated by rapid maxillary expansion. Methods: A sample of 60 subjects in the early mixed dentition with palatally displaced canines diagnosed on posteroanterior radiographs was enrolled in the trial. Their age range at the first observation (T1) was 7.6 to 9.6 years, with a prepubertal stage of skeletal maturity (CS1 or CS2). The 60 subjects were randomly allocated to the treatment group (TG, 35 subjects) or the no-treatment group (NTG, 25 subjects). The TG was treated with a banded rapid maxillary expander; after expansion, all patients were retained with the expander in place for 6 months. Thereafter, the expander was removed, and the patients wore a retention plate at night for a year. The NTG received no treatment. All subjects were reevaluated in the early permanent dentition (T2) (postpubertal CS4). The number of dropouts was recorded. The main outcome recorded at T2 was successful or unsuccessful eruption of the maxillary permanent canines. The starting forms at T1 for measurements on posteroanterior and panoramic films were compared in the 2 groups with the Mann-Whitney U test (P \0.05). The prevalence rates of successful and unsuccessful treatments in the TG were compared with those in NTG with chi-square tests (P \0.05). From T1 to T2, there were 3 dropouts in each group. Results: The final sample comprised 32 subjects in the TG and 22 subjects in the NTG. No statistically significant differences were found for any variable at T1. The prevalence rates of successful eruption of the maxillary canines were 65.7% (21 subjects) in the TG and 13.6% (3 subjects) in the NTG. The comparison was statistically significant (chi-square 5 12.4; P \0.001). Subjects with palatally displaced canines in the early mixed dentition do not have transverse deficiency of the maxillary arch. Conclusions: The use of a rapid maxillary expander as an early interceptive approach is effective for increasing the rate of eruption of palatally displaced canines. (Am J Orthod Dentofacial Orthop 2009;136:657-61)

The purpose of this cephalometric study was to analyse the treatment and post-treatment craniofacial effects of a facemask (FM) combined with a bite block (BB) with specific regard to the sagittal pharyngeal dimensions in subjects with a Class III malocclusion when compared with an untreated Class III control group. The FM/BB group (22 subjects, 12 females and 10 males) had a mean age pre-treatment (T1) of 8.9 +/- 1.5 years, at the end of active treatment (T2) of 10.5 +/- 1.3 years, and post-treatment (T3) of 12.6 +/- 1.9 years. The treated group was compared with a control group of 14 subjects (6 females and 8 males) with untreated Class III malocclusions that matched the FM/BB group as to age at T1, T2, and T3, observation periods and skeletal maturation. Comparisons of the T2-T1 and T3-T1 changes between the two groups were analysed with the Mann-Whitney test. Significant favourable skeletal changes in the maxilla and mandible were observed in the treated group both after Ts2 and T3. No significant short- or long-term changes in the sagittal oropharyngeal and nasopharyngeal airway dimensions were induced by maxillary protraction in subjects with a Class III malocclusion when compared with untreated controls.

Introduction: The purpose of this study was to evaluate the long-term stability of quad-helix/crib treatment in subjects with dentoskeletal open bite. Methods: Twenty-eight subjects (11 boys, 17 girls; mean age, 8.2 6 1.3 years) were treated consecutively with quad-helix/crib appliances. The patients were reevaluated at the end of active treatment with the quad-helix/crib (mean age, 9.7 6 1.6 years) and at least 5 years after the completion of treatment (mean age, 14.6 6 1.9 years). A control group of 20 untreated subjects with the same dentoskeletal disharmony was used for the statistical comparison (Mann-Whitney U test). Results: In the long term, the quad-helix/crib group showed a significant reduction in the ANB angle (À1.3 ), a downward rotation of the palatal plane (1.8 ), a greater increase in overbite (2.1 mm), and a decrease in overjet (À1.5 mm) when compared with the controls. Conclusions: In the long term, the use of the quad-helix/crib appliance led to successful outcomes in about 93% of the patients considered. Correction of dentoskeletal open bite was associated with a clinically significant downward rotation of the palatal plane. (Am J Orthod Dentofacial Orthop 2013;143:695-703)