Effect of rapid maxillary expansion on skeletal, dental, and nasal structures: a postero-anterior cephalometric study

Abstract

The purpose of this study was to compare the transverse dimensions of skeletal, dental, and nasal structures of a group of patients with maxillary narrowness before and after rapid maxillary expansion (RME) with an untreated control group using postero-anterior (PA) cephalometric radiographs. The material consisted of PA cephalograms of 25 children with a posterior crossbite (mean age 13 years 4 months), and 25 age- and sex-matched controls (mean age 13 years 11 months). Both groups consisted of 20 females and five males. Thirty-four reference points were digitized using the Dentofacial Planner software program. The 17 variables studied consisted of six skeletal, four dental, and seven intra-nasal linear measurements. Student's t-tests were used to compare the differences between the groups, and the effect of RME on skeletal, dental, and nasal structures. RME produced small, but statistically significant changes in maxillary width, upper and lower molar widths, the width between upper central incisor apices, and intra-nasal width. When compared with previous studies, the changes observed were similar for patients of a similar age group, but less than reported for a younger population. There is some evidence that the pattern of expansion produced by RME will vary depending on the age and maturity of the subject.

Immediate effects of rapid maxillary expansion on the naso-maxillary facial soft tissue using 3D stereophotogrammetry

“…The expansion is often pyramidal in shape with the greatest expansion around the region of the nasal aperture. [4][5][6][7][8] Studies based on twodimensional lateral cephalograms have shown that the maxilla displaces downwards and forwards to a varying degree following RME treatment. 9 One of the most noticeable dental effects during RME activation is a diastema between the upper central incisors but tipping of the maxillary posterior teeth and alveolar processes laterally have also been reported.…”

Evaluation and comparison of root resorption between tooth-borne and tooth-tissue borne rapid maxillary expansion appliances: A CBCT study

“…These are technical problems such as loosening or breakage of the expander and biological problems such as pain, 2 nonopening of the midpalatal suture, 3 dental tipping, 4 root resorption of the anchor teeth, 5 gingival recession, 6 widening of the nasal root and nasal bridge, 7 swelling and reddening, 8 and occurrence of nasal septum asymmetries. 8 Root resorption occurs because of individual biologic and genetic predisposition and the effect of mechanical factors.…”

CBCT of skeletal changes following rapid maxillary expansion to increase arch-length with a development-dependent bonded or banded appliance

“…[13][14][15] Traditionally, the effects of RME are evaluated using casts and/or two-dimensional (2D) radiographs, but reproducibility of 2D radiographs is problematic, and overlapping images are difficult to assess. [16][17][18] Conebeam computed tomography (CBCT) provides more accurate and reproducible imaging 19,20 for assessing all craniofacial skeletal structures, including the circummaxillary sutures. [21][22][23] Common RME appliances are the bonded (McNamara type) [24][25][26][27] and the tooth banded (Hyrax type).…”