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Objectives: To perform an in vitro qualitative and quantitative evaluation of the enamel surface (by scanning electronic microscopy [SEM] and measuring polishing time and roughness analysis, respectively) among four methods to remove remaining orthodontic adhesive after bracket debonding., Materials and Methods: Forty-one human premolars were randomly divided into four groups (n = 10) according to the adhesive remnant removal method and one tooth was used as control: Group 1 (G1): Enhance (Dentsply, Milford, USA); Group 2 (G2): Fiberglass (TDV, Pomerode, Brazil); Group 3 (G3): DU10CA-Ortho (Dian Fong Industrial, Shenzhen, China); Group 4 (G4): Sof-Lex Pop-On (3M ESPE, Seefeld, Germany). Roughness was measured before bonding and after complete removal of the remaining adhesive (Ra2). SEM analysis was performed on one sample of each group after adhesive removal and polishing. The time required for adhesive remnant removal and polishing was measured in all groups. Analysis of variance and Tukey post hoc for pairwise comparison was applied to compare polishing times among groups and analysis of covariance was used to compare Ra2 means., Results: Comparison between groups show that G4 presented the lowest Ra2 mean (0.43 μm)c followed by G3 (0.71 μm)ac, G1 (1.06 μm)ab, and G2 (1.21 μm)b - different letters, statistically different at P ≤ 0,05. In addition, Fiberglass was more time-consuming for adhesive remnant removal than other methods (P ≤ .05). SEM analysis showed that some enamel damage occurred for all methods., Conclusions: All methods were able to remove the remaining adhesive and polish the enamel. The DU10CA-Ortho and Sof-Lex methods promoted better polishing of the enamel surface and exhibited a similar time-consuming process., (© 0000 by The EH Angle Education and Research Foundation, Inc.)

Objective: The objective of the present study was to conduct a randomized clinical trial comparing the effects of rapid maxillary expansion (RME) and slow maxillary expansion (SME). Maxillary permanent first molar root length and tooth movement through the alveolus were studied using cone-beam computed tomography (CBCT)., Methods: Subjects with maxillary transverse deficiencies between 7 and 10 years of age were included. Using Haas-type expanders, children were randomly assigned to two groups: RME (19 subjects, mean age of 8.60 years) and SME (13 subjects, mean age of 8.70 years)., Results: Buccal cortical, buccal bone thicknesses and dentoalveolar width decreased in both groups. In the RME group the greatest decrease was related to distal bone thickness (1.26 mm), followed by mesial bone thickness (1.09 mm), alveolar width (0.57 mm), and the buccal cortical (0.19 mm). In the SME group the mesial bone thickness decreased the most (0.87 mm) and the buccal cortical decreased the least (0.22 mm). The lingual bone thickness increased in the RME and SME groups (0.56 mm and 0.42 mm, respectively). The mesial root significantly increased in the RME group (0.52 mm) and in the SME group (0.40 mm), possibly due to incomplete root apex formation at T1 (prior to installation of expanders)., Conclusions: Maxillary expansion (RME and SME) does not interrupt root formation neither shows first molar apical root resorption in juvenile patients. Although slightly larger in the RME group than SME group, both activation protocols showed similar buccal bone thickness and lingual bone thickness changes, without significant difference; and RME presented similar buccal cortical bone changes to SME.

Objective:: The aim of this randomized clinical trial was to evaluate the dental, dentoalveolar, and skeletal changes occurring right after the rapid maxillary expansion (RME) and slow maxillary expansion (SME) treatment using Haas-type expander., Methods:: All subjects performed cone-beam computed tomography (CBCT) before installation of expanders (T1) and right after screw stabilization (T2). Patients who did not follow the research parameters were excluded. The final sample resulted in 21 patients in RME group (mean age of 8.43 years) and 16 patients in SME group (mean age of 8.70 years). Based on the skewness and kurtosis statistics, the variables were judged to be normally distributed and paired t-test and student t-test were performed at significance level of 5%., Results:: Intermolar angle changed significantly due to treatment and RME showed greater buccal tipping than SME. RME showed significant changes in other four measurements due to treatment: maxilla moved forward and mandible showed backward rotation and, at transversal level both skeletal and dentoalveolar showed significant changes due to maxillary expansion. SME showed significant dentoalveolar changes due to maxillary expansion., Conclusions:: Only intermolar angle showed significant difference between the two modalities of maxillary expansion with greater buccal tipping for RME. Also, RME produced skeletal maxillary expansion and SME did not. Both maxillary expansion modalities were efficient to promote transversal gain at dentoalveolar level. Sagittal and vertical measurements did not show differences between groups, but RME promoted a forward movement of the maxilla and backward rotation of the mandible.

The objective of this article was to report a clinical case of a patient with solitary median maxillary central incisor syndrome. He was treated with rapid maxillary expansion and evaluated with computed tomography. The boy, aged 6 years 7 months, had a single maxillary central incisor in the midline, posterior crossbite, prominent midpalatal ridge, indistinct philtrum, no incisive papilla, and no labial frenulum. No other systemic anomalies were found. Posteroanterior cephalometric radiography showed skeletal atresia of the maxilla that was corrected with rapid maxillary expansion. A Haas expander was used and activated twice per day (quarter turn per activation) for 15 days. The procedure was monitored with computed tomography to evaluate any effect on the intermaxillary suture and tooth. Although the crossbite was clinically corrected after the expansion, radiographs and tomographs showed no opening of the midpalatal suture. Rapid maxillary expansion resulted in neither midpalatal suture opening nor transverse increase of the maxillary skeletal base in this patient., (Copyright © 2010 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)