Dentofacial and upper airway characteristics of mild and severe class II division 1 subjects

The aim of this retrospective, cross-sectional study was to assess whether mild and severe Class II division 1 subjects have craniofacial and upper airway characteristics, which relate to the severity of Class II as judged by overjet or ANB angle. The sample consisted of pre-treatment lateral cephalograms and dental casts of 131 males and 115 females (mean age 10.4 ± 1.6). Inclusion criteria were: healthy Caucasian subjects, at least ¾ Class II first molar relationship on both sides and overjet ≥ 4 mm. The cephalograms were traced and digitized. Distances and angular values were computed. Mild and severe Class II was defined by overjet (<10 mm/≥ 10 mm) or by ANB angle (<7 degrees/≥7 degrees). Statistics were performed with two-sample t-test and Pearson's correlation analysis. In the two overjet groups, significant differences were mainly found for incisor inclination while the two ANB groups differed significantly in SNA, WITS, Go-Pg, SpaSpp/MGo, SN/MGo, and Ar-Gn. The shortest airway distance between the soft palate and the posterior pharyngeal wall was significantly correlated to the NS/Ar angle. Statistical analysis revealed several significant correlations. Patients with a large overjet or ANB angle differed significantly from patients with a small overjet or ANB angle mainly in their incisor inclination. In the present sample, the overjet and to some extent also the ANB angle is determined by soft tissue or individual tooth position rather than by skeletal background. In retrognathic patients, a tendency towards smaller airway dimensions was found. However, statistical analysis did not reveal a strong connection between upper airway and dentoskeletal parameters, but a large interindividual variatio

Final Posttreatment Occlusion in Patients With Unilateral Cleft Lip and Palate

Objective: To evaluate final posttreatment occlusion in patients with complete unilateral cleft lip and palate (cUCLP) by comparing (1) 3 treatment centers, (2) males and females, (3) cleft and noncleft sides, (4) right- and left-sided clefts, and (5) orthodontic treatment with/without orthognathic surgery (OS). Design: Retrospective cohort study. Patients: Blinded posttreatment dental casts of 56 patients (19.4 ± 1.4 years) with cUCLP from 3 centers in Switzerland. Main outcome measure: Occlusal assessment using the modified Huddart/Bodenham (MHB) index. Results: Our sample comprised 35 males and 21 females, 46 with left- and 10 with right-sided clefts, of which 32 had undergone OS. The final posttreatment occlusion showed a median MHB score of 0 (interquartile range: -1.0 to 2.0) in the total sample and did not seem to depend on treatment center, sex, or OS. The MHB scores for the anterior buccal and the buccal segments were more negative on the cleft than on the noncleft side (P = .002 and P = .006, respectively). When the cleft was on the left side, the MHB score tended to be more positive in the labial (P = .046) and anterior buccal segments (P = .034). Conclusions: This study shows a very satisfactory final posttreatment occlusion in patients with cUCLP. The more constricted buccal occlusion on the cleft side emphasizes the attention that should be given in correcting the more medially positioned lesser maxillary segment. The influence of cleft-sidedness should be analyzed further on a sample including more patients with right-sided clefts. Keywords: Treatment outcome; cleft lip and palate; crossbite; dental arch relationships; dental occlusion; final post-treatment; multicentre study

In situ uniaxial pressure cell for x-ray and neutron scattering experiments

We present an in situ uniaxial pressure device optimized for small angle x-ray and neutron scattering experiments at low-temperatures and high magnetic fields. A stepper motor generates force, which is transmitted to the sample via a rod with an integrated transducer that continuously monitors the force. The device has been designed to generate forces up to 200 N in both compressive and tensile configurations, and a feedback control allows operating the system in a continuous-pressure mode as the temperature is changed. The uniaxial pressure device can be used for various instruments and multiple cryostats through simple and exchangeable adapters. It is compatible with multiple sample holders, which can be easily changed depending on the sample properties and the desired experiment and allow rapid sample changes

Dentofacial and upper airway characteristics of mild and severe class II division 1 subjects

The aim of this retrospective, cross-sectional study was to assess whether mild and severe Class II division 1 subjects have craniofacial and upper airway characteristics, which relate to the severity of Class II as judged by overjet or ANB angle. The sample consisted of pre-treatment lateral cephalograms and dental casts of 131 males and 115 females (mean age 10.4 ± 1.6). Inclusion criteria were: healthy Caucasian subjects, at least &frac34; Class II first molar relationship on both sides and overjet ≥ 4 mm. The cephalograms were traced and digitized. Distances and angular values were computed. Mild and severe Class II was defined by overjet (<10 mm/≥ 10 mm) or by ANB angle (<7 degrees/≥7 degrees). Statistics were performed with two-sample t-test and Pearson's correlation analysis. In the two overjet groups, significant differences were mainly found for incisor inclination while the two ANB groups differed significantly in SNA, WITS, Go-Pg, SpaSpp/MGo, SN/MGo, and Ar-Gn. The shortest airway distance between the soft palate and the posterior pharyngeal wall was significantly correlated to the NS/Ar angle. Statistical analysis revealed several significant correlations. Patients with a large overjet or ANB angle differed significantly from patients with a small overjet or ANB angle mainly in their incisor inclination. In the present sample, the overjet and to some extent also the ANB angle is determined by soft tissue or individual tooth position rather than by skeletal background. In retrognathic patients, a tendency towards smaller airway dimensions was found. However, statistical analysis did not reveal a strong connection between upper airway and dentoskeletal parameters, but a large interindividual variation

Final Posttreatment Occlusion in Patients With Unilateral Cleft Lip and Palate

Objective: To evaluate final posttreatment occlusion in patients with complete unilateral cleft lip and palate (cUCLP) by comparing (1) 3 treatment centers, (2) males and females, (3) cleft and noncleft sides, (4) right- and left-sided clefts, and (5) orthodontic treatment with/without orthognathic surgery (OS). Design: Retrospective cohort study. Patients: Blinded posttreatment dental casts of 56 patients (19.4 ± 1.4 years) with cUCLP from 3 centers in Switzerland. Main outcome measure: Occlusal assessment using the modified Huddart/Bodenham (MHB) index. Results: Our sample comprised 35 males and 21 females, 46 with left- and 10 with right-sided clefts, of which 32 had undergone OS. The final posttreatment occlusion showed a median MHB score of 0 (interquartile range: -1.0 to 2.0) in the total sample and did not seem to depend on treatment center, sex, or OS. The MHB scores for the anterior buccal and the buccal segments were more negative on the cleft than on the noncleft side (P = .002 andP = .006, respectively). When the cleft was on the left side, the MHB score tended to be more positive in the labial (P = .046) and anterior buccal segments (P = .034). Conclusions: This study shows a very satisfactory final posttreatment occlusion in patients with cUCLP. The more constricted buccal occlusion on the cleft side emphasizes the attention that should be given in correcting the more medially positioned lesser maxillary segment. The influence of cleft-sidedness should be analyzed further on a sample including more patients with right-sided clefts.</p