Examinando por Autor "Arriola-Guillén, L.E."

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    ÍtemAcceso Abierto
    Influence of maxillary posterior dentoalveolar discrepancy on angulation of maxillary molars in individuals with skeletal open bite
    (Springer Berlin Heidelberg, 2016) Arriola-Guillén, L.E.; Aliaga-Del Castillo, A.; Flores-Mir, C.
    Background: The aim of this study was to determine the effect of the maxillary posterior dentoalveolar discrepancy (MPDD) on the angulation of maxillary molars in open bite subjects. Methods: Pre-treatment lateral cephalograms of 90 young adults with skeletal open bite were examined. The sample initially included six groups categorized according to MPDD condition (present or absent) and sagittal skeletal facial growth patterns (classes I, II, or III). Then, the sample was separated into two groups according to MPDD (present = 50, absent = 40). When the eruption of the maxillary third molar was apparently blocked by the presence of an erupted second molar, a MPDD was considered. Maxillary molar angulation was measured. Independent T test was performed to determine differences between the groups considering MPDD condition. Principal component analysis (PCA) and multivariate analysis (MANCOVA) test were also developed. Results: A decreased molar angulation was found in all groups with MPDD (overall p < 0.001, class I—p < 0.001, class II—p < 0.001, and class III—p < 0.05). The maxillary first and second molars angulations were lower between approximately 7° and 14° in cases with posterior discrepancy. The PCA was used to reduce the number of initial cephalometric variables; thereafter, a MANCOVA test was applied. Significance was only found for MPDD (p < 0.001), APDI (p = 0.001), and ratio (A′6′/A′P′) (p = 0.026) for maxillary first molar angulation and APDI (p = 0.011) and MPDD (p < 0.001) for maxillary second molar angulation. Conclusions: The MPDD generates a major mesial displacement of the second and first molar roots with a concurrent simultaneous distal angulation of the associated crowns in individuals with skeletal open bite. © 2016, The Author(s).
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    ÍtemAcceso Abierto
    Molar heights and incisor inclinations in adults with Class II and Class III skeletal open-bite malocclusions
    (2014) Arriola-Guillén, L.E.; Flores-Mir, C.
    Introduction The aim of this research was to compare maxillary and mandibular molar heights and incisor inclinations in patients with skeletal open-bite Class II, patients with skeletal open-bite Class III, and an untreated control group. Methods Pretreatment lateral cephalograms of 70 orthodontic patients (34 men, 36 women) between 16 and 40 years of age were examined. The sample was divided into 3 groups according to facial growth pattern and overbite. The control group (n = 25) included normodivergent Class I subjects with adequate overbite; the skeletal open-bite Class II group (n = 25) and the skeletal open-bite Class III group (n = 20) included hyperdivergent Class II or Class III subjects with negative overbite. Measurements considered were ANB angle, palatal and mandibular plane angles, maxillary incisor palatal plane angulation, and mandibular incisor mandibular plane angulation, as well as the distance from the palatal or the mandibular plane to the mesial cusp of the molars. Multivariate analysis of covariance and multivariate analysis of variance tests were used to determine the differences between the groups, followed by the Tukey post-hoc test. Additionally, the Mann-Whitney U test and Kruskall-Wallis test were performed. Results Significant differences in molar height were found (P <0.001). A 4-mm difference in maxillary molar height between the skeletal open-bite and control groups was found. Mandibular molar height was greater in the skeletal open-bite Class II group (P <0.001). Maxillary incisor palatal plane angulation was greater in the skeletal open-bite Class III group by approximately 6°. Mandibular incisor to mandibular plane angulation was 10° more lingual in the skeletal open-bite Class III group (P <0.001). Conclusions The skeletal open-bite groups had greater molar heights than did the control group. The skeletal open-bite Class II group had more eruption of the mandibular molars. The maxillary incisors were more proclined and the mandibular incisors were more lingual in the skeletal open-bite Class III group. © 2014 by the American Association of Orthodontists.
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    ÍtemAcceso Abierto
    Semi-longitudinal Study of the Mcnamara Cephalometric Triangle in Class II and Class III Subjects Grouped by Cervical Vertebrae Maturation Stage [Estudio semi-longitudinal del triángulo cefalométrico de Mcnamara en sujetos de clase II y clase III agrupados por estadio de maduración de vertebras cervicales]
    (2015) Arriola-Guillén, L.E.; Fitzcarrald, F.D.; Flores-Mir, C.
    The aim was to compare the McNamara cephalometric triangle values in untreated normodivergent Class II and Class III malocclusion subjects of Latin American origin grouped by cervical vertebrae maturation stage to an untreated Class I malocclusion normodivergent control group. The study was conducted on a sample of 610 pretreatment lateral cephalograms (250 male, 360 female), examined and grouped according to their anteroposterior skeletal relationship (Class I, II or III), cervical vertebrae maturation stage (Pre Pubertal Peak P1 = CS1 and CS2, Pubertal Peak P2= CS3 and CS4, and Post Pubertal Peak P3 = CS5 and CS6) and sex. Co-A, Co-Gn and ENA-Me were measured in each lateral cephalogram. ANOVA and Tukey HSD post-hoc tests were performed to determine differences between the groups. The results showed that in males, the greatest maxillary and mandibular dimensional increases occurred during the P3 stage (CS5 to CS6), while in females, they occurred in the P2 stage (CS3 to CS4). The Co-A and Co-Gn showed significant differences between the malocclusion classes (p<0.05). The maxillary lengths in Class II subjects and the mandibular lengths in Class III subjects were already higher at the beginning of the period evaluated (P1). A worsening trend for the Class II and III malocclusions was identified during the period evaluated. Finally, changes in the McNamara cephalometric triangle values were markedly different in the three normodivergent skeletal malocclusion classes. In these Latin American subjects the pubertal growth spurt occurred at different times with respect to the Caucasian and Asian norms. Sociedad Argentina de Investigación Odontológica.El objetivo del estudio fue comparar los valores del triángulo cefalométrico de McNamara en sujetos normodivergentes no tratados con maloclusión de Clase II y Clase III de origen latinoamericano agrupados por estadío de maduración de vértebras cervicales, en comparación con un grupo control sin tratamiento, normodivergentes y con maloclusión de Clase I. El estudio se realizó sobre una muestra de seiscientos diez cefalogramas laterales de cabeza pretratamiento (250 hombres, 360 mujeres) que fueron agrupados de acuerdo a su relación esquelética sagital (Clase I, II ó III), estadío de maduración vértebras cervicales (pre pico puberal P1 = CS1 y CS2, pico puberal P2 = CS3 y CS4, y post pico puberal P3 = CS5 y CS6) y sexo. Se midió en cada cefalograma el triángulo cefalométrico de McNamara Co-A, Co-Gn y ENA-Me. Se realizaron las pruebas de ANOVA y post-hoc Tukey HSD para determinar las diferencias entre grupos.Los resultados en hombres muestran que los mayores aumentos maxilares y mandibulares se produjeron durante la etapa P3 (CS5 para CS6), mientras que en las mujeres se produjeron en la etapa P2 (CS3 para CS4). Las distancias Co-A y Co-Gn muestran diferencias significativas entre las diferentes clases (p <0,05). La longitud maxilar de los sujetos de Clase II y la longitud mandibular de los sujetos de Clase III estuvieron aumentadas al inicio del período evaluado (P1). Se identificó una tendencia al empeoramiento de las maloclusiones de Clase II y III durante el período evaluado. Finalmente los cambios en los valores del triángulo cefalo- métrico de McNamara fueron marcadamente diferentes en las tres clases de maloclusión en sujetos normodivergentes. En estos sujetos latinoamericanos el estirón puberal se produjo en momentos diferentes con respecto a la raza caucásica y las normas asiáticas.
  • Miniatura
    ÍtemAcceso Abierto
    Skeletal and dentoalveolar bilateral dimensions in unilateral palatally impacted canine using cone beam computed tomography
    (Springer Berlin Heidelberg, 2017) D' Oleo-Aracena, M.F.; Arriola-Guillén, L.E.; Rodríguez-Cárdenas, Y.A.; Ruíz-Mora, G.A.
    Background: The aim of this investigation was to compare skeletal and dentoalveolar measurements of subject with unilateral palatally impacted canine versus the unaffected contralateral side on cone beam computed tomography (CBCT). Methods: A cross-sectional study (split mouth design) that included 28 CBCTs (i.e., 56 sides) with unilaterally impacted maxillary canines was performed. After conducting a pilot test to gauge the researcher, heights and widths of skeletal and dentoalveolar variables obtained in the maxilla were measured using coronal and axial views. The angulations of incisors were also measured, and the side with impaction and the unaffected side were compared. Paired sample t test and Wilcoxon signed-rank test were used. Results: Significant statistical differences (2 mm, p < 0.001) were found between the impacted and non-impacted side measurements from the mid-palatine raphe to the first premolar (proximal alveolar bone crest between the canine (deciduous or permanent) and first premolar); the distance were significantly lower (12.72 ± 2.25 mm) than in the side without impaction (14.67 ± 2.00 mm). Also, the central and lateral incisor angulations showed significant reductions; presenting disto-angulated incisors on the impacted canine side (86.14 ± 7.70° and 74.75 ± 12.67°, respectively) and mesial-angulated incisors on the non-impacted side (91.63 ± 6.79° and 81.21 ± 8.56° respectively). The other skeletal and dentoalveolar measurements showed no significant differences. Conclusions: The width from the median raphe to the first premolar is lower in the side of maxillary palatal impacted canines than in the side without impaction. Lateral angulations of incisors were disto-angulated on the side of impacted canines. Both conditions have clinical implications in the orthodontic treatment. © 2017, The Author(s).