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This study investigated correlations between airway size and age, sex, and skeletal patterns; identified airway change trends; and measured volumetric norms in children via cone-beam computed tomography.Four hundred twenty nontreated white patients were stratified by age, sex, and anteroposterior skeletal pattern. The nasopharyngeal airway (NPA), oropharyngeal airway (OPA), and total pharyngeal airway (TPA) volumes were delineated on 3-dimensional digital cephalograms. SPSS (SPSS, Chicago, Ill) was used to run an analysis of variance and post-hoc analyses.The Class III group had significantly larger OPA volumes than Class I and II groups. Male subjects had considerably larger NPA volumes than female subjects. Age was significantly associated with all 3 airway volumes (P 0.05). The young cohort (ages, 9-10 years) had a mean TPA of 11,435.34 ± 484.45 mmAn effect of skeletal classification on OPA and a sex effect on NPA were observed. The annual change in the mean of TPA volume decreased in subjects aged 10-12 years, then rebounded until 14 years. TPA change peaked in female subjects 1 year before male subjects.

Purpose: The objective of this study was to compare the treatment outcomes and stability of patients with Class II malocclusion treated with either functional appliances or surgical mandibular advancement. Material: The early-treatment group consisted of 30 patients (15 girls, 15 boys), with a mean age of 10 years 4 months (range, 7 years 5 months to 12 years 5 months), who received either Frankel II (15 patients) or Herbst appliances (15 patients). The surgical group consisted of 30 patients (23 female, 7 male), with a mean age of 27 years 2 months (range, 13 years 0 months to 53 years 10 months). They were treated with bilateral sagittal split ramus osteotomies with rigid fixation. Lateral cephalograms were taken for the early-treatment group at T1 (initial records), T2 (completion of functional appliance treatment), and Tf (completion of comprehensive treatment). In the surgical group, lateral cephalograms were taken at T1 (initial records), T2 (presurgery), T3 (postsurgery), and Tf (completion of comprehensive treatment). The average times from the completion of functional appliance treatment or surgery to the final cephalograms were 35.8 months and 34.9 months, respectively. A mixed-design analysis of variance was used to compare changes within and between groups. Results: In the functional appliance group, the mandible continued to grow in a favorable direction even after discontinuation of the functional appliance. Both groups had stable results over time. Both groups finished treatment with the same cephalometric measurements. Significant skeletal and soft tissue changes were noted in the treatment groups due to either functional or surgical advancement of the mandible. More vertical relapse was noted in the surgical group than in the functional group. Conclusions: This study suggests that early correction of Class II dentoskeletal malocclusions with functional appliances yields favorable results without the possible deleterious effects of surgery.

The mandibular anterior repositioning appliance (MARA) is a tooth-borne functional appliance for use in patients with Class II malocclusions; it positions the mandible forward into a Class I occlusion. The aim of this study was to investigate the MARA's dental and skeletal effects on anterior, posterior, and vertical changes in 30 Class II patients. The treatment group consisted of 12 boys with an average age of 11.2 years and 18 girls with an average age of 11.3 years. A pretreatment cephalometric radiograph was taken 2 weeks before treatment, and a posttreatment cephalometric radiograph was taken 6 weeks after removal of the MARA, with an average treatment time of 10.7 months. The mean and standard deviation were calculated for each cephalometric variable, and Student t tests were performed to determine the statistical significance of the changes. The results of the study showed that the MARA produced measurable treatment effects on the skeletal and dental elements of the craniofacial complex. These effects included a considerable distalization of the maxillary molar, a measurable forward movement of the mandibular molar and incisor, a significant increase in mandibular length, and an increase in posterior face height. The effects of the MARA treatment were then compared with those of the Herbst and Fränkel appliances. The treatment results of the MARA were very similar to those produced by the Herbst appliance but with less headgear effect on the maxilla and less mandibular incisor proclination than observed in the Herbst treatment group.

Although many improvements have been made in orthodontic surgical procedures for mandibular retrognathism, relapse continues to occur. This study was designed to compare the stability of rigid and nonrigid fixation between 2 groups of patients who had undergone mandibular advancement surgery via sagittal split ramus osteotomy. Retrospective cephalometric measurements were made on 54 randomly selected orthognathic surgical patients. The patients, 7 males and 47 females, were divided into 2 groups: 28 patients stabilized by means of rigid fixation and 26 patients fixated with interosseous wires. The age of the patients ranged from 15.3 to 49.7 years. Lateral cephalograms were used to evaluate each patient at 3 distinct intervals: 7.0 ± 2.0 days before surgery (T1), 34.4 ± 15.0 days postsurgery (T2), and 458 ± 202 days after sagittal split osteotomy (T3). Eighteen linear and angular measurements were recorded and differences between the 3 time periods were evaluated. Statistical analyses were performed to assess the differences in the 2 fixation types between and within each group at different time intervals. The following measurements showed statistically significant skeletal relapse over time, for the P value.0028: Co-Go, ANS-Xi-Pm, IMPA, overbite, and overjet. The remaining variables showed no statistically significant relapse. The only measurement that showed a statistically significant group difference between T1 and T2 was DC-Xi-Pm. Results of the study led to the following conclusions: there was statistically significant relapse in mandibular length, lower anterior face height, mandibular arc, lower incisor inclination, overbite, and overjet in each group, regardless of the type of fixation. The potential was greater for relapse in patients stabilized with transosseous wiring. Although multifactorial, relapse in overbite and overjet may be a combination of skeletal and dental changes. (Am J Orthod Dentofacial Orthop 2000;118:397-403).