23 research outputs found
Three-dimensional treatment outcomes in Class II patients treated with the Herbst appliance: A pilot study
The aims of this study were to analyze 3-dimensional skeletal changes in subjects with Class II malocclusion treated with the Herbst appliance and to compare these changes with treated Class II controls using 3-dimensional superimposition techniques
Three-Dimensional Regional Displacements After Mandibular Advancement Surgery: One Year of Follow-Up
To evaluate the association of 3-dimensional changes in the position of the condyles, rami, and chin at splint removal and 1 year after mandibular advancement surgery
Three-dimensional condylar changes from Herbst appliance and multibracket treatment: A comparison with matched Class II elastics
INTRODUCTION: The purpose of this study was to quantify and qualify the 3-dimensional (3D) condylar changes using mandibular 3D regional superimposition techniques in adolescent patients with Class II Division 1 malocclusions treated with either a 2-phase or single-phase approach. METHODS: Twenty patients with Herbst appliances who met the inclusion criteria and had cone-beam computed tomography (CBCT) images taken before, 8Â weeks after Herbst removal, and after the completion of multibracket appliance treatment constituted the Herbst group. They were compared with 11 subjects with Class II malocclusion who were treated with elastics and multibracket appliances and who had CBCT images taken before and after treatment. Three-dimensional models generated from the CBCT images were registered on the mandible using 3D voxel-based superimposition techniques and analyzed using semitransparent overlays and point-to-point measurements. RESULTS: The magnitude of lateral condylar growth during the orthodontic phase (T2-T3) was greater than that during the orthopedic phase (T1-T2) for all condylar fiducials with the exception of the superior condyle (PÂ <0.05). Conversely, posterior condylar growth was greater during the orthopedic phase than the subsequent orthodontic phase for all condylar fiducials (PÂ <0.05). The magnitude of vertical condylar development was similar during both the orthopedic (T1-T2) and orthodontic phases (T2-T3) across all condylar fiducials (PÂ <0.05). Posterior condylar growth during the orthodontic phase (T2-T3) of the 2-phase approach decreased for all condylar fiducials with the exception of the posterior condylar fiducial (PÂ <0.05) when compared with the single-phase approach. CONCLUSIONS: Two-phase treatment using a Herbst appliance accelerates condylar growth when compared with a single-phase regime with Class II elastics. Whereas the posterior condylar growth manifested primarily during the orthopedic phase, the vertical condylar gains occurred in equal magnitude throughout both phases of the 2-phase treatment regime
Three-dimensional analysis of maxillary changes associated with facemask and rapid maxillary expansion compared with bone anchored maxillary protraction
Our objectives in this study were to evaluate in 3 dimensions the growth and treatment effects on the midface and the maxillary dentition produced by facemask therapy in association with rapid maxillary expansion (RME/FM) compared with bone-anchored maxillary protraction (BAMP)
Efficiency of light-emitting diode and halogen units in reducing residual monomers
In this in-vitro study, we aimed to compare the residual monomers in composites beneath brackets bonded to enamel, using a light-emitting diode (LED) or a halogen unit, and to compare the residual monomers in the central to the peripheral areas of the composite
3D Quantification of Mandibular Asymmetry through Cone Beam Computed Tomography
To determine if 3D shape analysis precisely diagnoses right and left differences in asymmetry patient
Three-dimensional cone-beam computed tomography for assessment of mandibular changes after orthognathic surgery
The purpose of this study was to assess alterations in the 3-dimensional (3D) position of the mandibular rami and condyles in patients receiving either maxillary advancement and mandibular setback or maxillary surgery only
Superposition tridimensionnelle (3-D) sur la base du crâne pour l'évaluation longitudinale des effets de la croissance et du traitement
Pour évaluer les modifications liées à la croissance ou au
traitement, il est nécessaire de superposer les céphalogrammes
successifs sur une structure stable. En céphalométrie
bidimensionnelle (2-D), la base du crâne est souvent utilisée pour
les superpositions parce que les changements qu'elle subit après le
développement cérébral sont mineurs. Toutefois, sur les
céphalogrammes de profil et de face, les points de repère
basicraniens sont peu fiables. Dans cet article, nous présentons une
nouvelle méthode de superposition tridimensionnelle (3-D) basée sur
un enregistrement entièrement automatisé des intensités de
voxels, au niveau de la surface de la base du crâne. Le progiciel
utilisé permet l'évaluation quantitative des modifications qui
apparaissent dans le temps, grâce au calcul de la distance euclidienne
entre les surfaces du modèle tridimensionnel. Il permet également
l'appréciation visuelle de l'emplacement et de l'importance des
modifications au niveau des maxillaires, grâce à une surimpression
graphique. Les modifications sont visualisées par comparaison à des
tables de correspondance de couleur. On peut ainsi réaliser une
étude détaillée des modes d'adaptation chez les patients dont la
croissance et/ou le traitement ont provoqué des modifications
squelettiques cliniquement significatives