Dentoskeletal outcomes of a rapid maxillary expander with differential opening in patients with bilateral cleft lip and palate: A prospective clinical trial

Abstract

Introduction The purpose of this 2-arm parallel study was to evaluate the dentoskeletal effects of rapid maxillary expansion with differential opening (EDO) compared with the hyrax expander in patients with complete bilateral cleft lip and palate. Methods A sample of patients with complete bilateral cleft lip and palate was prospectively and consecutively recruited. Eligibility criteria included participants in the mixed dentition with lip and palate repair performed during early childhood and maxillary arch constriction with a need for maxillary expansion before the alveolar bone graft procedure. The participants were consecutively divided into 2 study groups. The experimental and control groups comprised patients treated with rapid maxillary expansion using EDO and the hyrax expander, respectively. Cone-beam computed tomography examinations and digital dental models of the maxillary dental arches were obtained before expansion and 6 months postexpansion. Standardized cone-beam computed tomography coronal sections were used for measuring maxillary transverse dimensions and posterior tooth inclinations. Digital dental models were used for assessing maxillary dental arch widths, arch perimeters, arch lengths, palatal depths, and posterior tooth inclinations. Blinding was used only during outcome assessment. The chi-square test was used to compare the sex ratios between groups (P <0.05). Intergroup comparisons were performed using independent t tests with the Bonferroni correction for multiple tests. Results Fifty patients were recruited and analyzed in their respective groups. The experimental group comprised 25 patients (mean age, 8.8 years), and the control group comprised 25 patients (mean age, 8.6 years). No intergroup significant differences were found for age, sex ratio, and dentoskeletal variables before expansion. No significant differences were found between the EDO and the hyrax expander groups regarding skeletal changes. The EDO promoted significantly greater increases of intercanine width (difference, 3.63 mm) and smaller increases in canine buccal tipping than the conventional hyrax expander. No serious harm was observed other than transitory variable pressure sensations on the maxillary alveolar process in both groups. Conclusions The EDO produced skeletal changes similar to the conventional hyrax expander. The differential expander is an adequate alternative to conventional rapid maxillary expanders when there is need for greater expansion in the maxillary dental arch anterior region. Registration This trial was not registered. Protocol The protocol was not published before trial commencement.

Dental arch size and shape after maxillary expansion in bilateral complete cleft palate:A comparison of three expander designs

“…However, the intragroup comparison showed no dental arch shape difference between H T1 and H T2, indicating that only the QH and EDO promoted changes in the shape of the dental arch after maxillary expansion ( Figure 6). The greater expansion in the anterior region of the maxillary dental arch described by Dalessandri et al 31 and Tindlund et al 32 using QH and by Garib et al 11 using EDO in BCLP patients appeared to be responsible for these shape differences. These changes in dental arch shape are positive for BCLP patients as a result of the triangular morphology of the dental arch described previously.…”

“…10 EDO promoted a greater expansion in the anterior region of the maxillary dental arch, with no skeletal differences from the traditional Hyrax. 11 No previous morphological analysis of the expander outcomes was performed in BCLP. The purpose of this study was to compare the effects of H, QH, and EDO on maxillary dental arch size and shape in patients with BCLP.…”

Tomographic evaluation of dentoskeletal effects of rapid maxillary expansion using Haas and Hyrax palatal expanders in children: A randomized clinical trial

“…Calculation of sample size was based on the ability to detect a difference in maxillary width of 1.1 mm (SD, 1.10), measured between the external cortical to the level of the deepest region of the palate ( 16 ), with an alpha of 5% and a test power of 80%.…”

Orthodontics in Relation with Alveolar Bone Grafting in CLP Patients

“…As the individuals with complete cleft lip and palate do not have midpalatal suture, constriction occurs mostly by the rotation of the lateral segment(s) inward, toward bony defect. Both the absence of the midpalatal bone and the soft tissue traction produced by lip and palate repair promote arch constriction [5,44,45].…”