Stability of class II correction with the Austro Repositioner associated with multi-brackets fixed appliances in dolichofacial patients.

BACKGROUND: The purposes of the present study were to evaluate the changes produced by the Austro Repositioner, and to assess the stability of Class II malocclusion treatment with the Austro Repositioner associated with fixed appliances and its capacity to control the vertical dimension in dolichofacial patients. METHODS: A group of patients with Class II malocclusion due to mandibular retrognathism and a dolichofacial growth pattern treated with the Austro Repositioner combined with fixed appliances were compared to a matched untreated control group of subjects with Class II malocclusion. Evaluations were made on the basis of lateral cephalograms taken at T1 (initial records), T2 (end of treatment), and T3 (1 year after treatment). Statistical comparisons were performed with paired- and two-sample t tests. RESULTS: The experimental (treated) group comprised 30 patients, 14 boys and 16 girls, and the control group comprised 30 subjects (15 boys and 15 girls) with similar ages at T1, T2 and T3. In the treated group, a significant decrease in the ANB angle was found (- 3.79 ± 1.46; p < 0.001). No significant differences were found in the maxillary skeletal measurements. In contrast, the SNB angle showed a significant increase of 3.77 ± 1.49 in the treated group compared with a nonsignificant increase of 0.77 ± 1.55 in the control group (p = 0.002). Vertical changes showed a significant decrease in the FMA angle (- 3.36 ± 1.62), while the lower anterior facial height distance and the overbite increased significantly in the treated group, reflecting a change in vertical dimensions after treatment. No significant changes were observed in either the treated or control group during the one-year posttreatment period; thus, the treatment results remained stable. CONCLUSIONS: The Austro Repositioner combined with fixed appliances could be considered an optimal treatment modality in Class II dolichofacial patients.

The Association Between Skeletal Facial Types and Third Molars Impaction in a Saudi Arabian Subpopulation: A CBCT Study.

Purpose: To assess the state of mandibular and maxillary third molars in relation to different facial types in a Saudi population using cone-beam computed tomography (CBCT) records. Patients and Methods: A retrospective study was performed on CBCTs. Statistical analysis determined the relationship between impacted maxillary and mandibular third molars and different skeletal facial types. The degree of third molar impaction was evaluated. Results: A total of 198 CBCTs from subjects were evaluated, with a mean age of 34.2 years. Archer II classification was found to be significantly associated with all skeletal profiles. The incidence of mesioangular impactions in lower third molar showed a notable increase in the brachyfacial group, which was statistically significant. Conclusion: In conclusion, this study demonstrates that different facial types are associated with the angulation of third molar impactions.

A theoretical analysis of longitudinal temporomandibular joint compressive stresses and mandibular growth.

OBJECTIVES: To determine if temporomandibular joint (TMJ) compressive stresses during incisor biting (1) differed between growing children over time, and (2) were correlated with Frankfort Horizontal-mandibular plane angle (FHMPA, °) and ramus length (Condylion-Gonion (Co-Go), mm). MATERIALS AND METHODS: Three-dimensional anatomical geometries, FHMPA and Co-Go, were measured longitudinally from lateral and posteroanterior cephalographs1 of children aged 6 (T1), 12 (T2), and 18 (T3) years. Geometries were used in numerical models to estimate subject-specific TMJ eminence shape and forces for incisor bite-forces of 3, 5, and 8 Newtons at T1, T2, and T3, respectively. TMJ compressive stresses were estimated via two steps: First, TMJ force divided by age-dependent mandibular condylar dimensions, and second, modified by loading surfaces' congruency. Analysis of variance and Tukey honest significant difference post-hoc tests, plus repeated measures and mixed effects model analyses were used to evaluate differences in variables between facial groups. Regression analyses tested for correlation between age-dependent compressive stresses, FHMPA, and Co-Go. RESULTS: Sixty-five of 842 potential subjects had T1-T3 cephalographs and were grouped by FHMPA at T3. Dolichofacial (FHMPA ≥ 27°, n = 36) compared to meso-brachyfacial (FHMPA< 27°, n = 29) subjects had significantly larger FHMPA at T1-T3, shorter Co-Go at T2 and T3 (all P < .01), and larger increases in TMJ compressive stresses with age (P < .0001). Higher compressive stresses were correlated with larger FHMPA (all R2 ≥ 0.41) and shorter Co-Go (all R2 ≥ 0.49). CONCLUSIONS: Estimated TMJ compressive stress increases from ages 6 to 18 years were significantly larger in dolichofacial compared to meso-brachyfacial subjects and correlated to FHMPA and Co-Go.

Association of facial type with possible bruxism and its related clinical features in adolescents: A cross-sectional study.

OBJECTIVES: The assessment of bruxism and its clinical characteristics is acknowledged in literature. This study aimed to evaluate the association of adolescents' facial patterns with bruxism and its related clinical features in the form of signs and symptoms. MATERIALS AND METHODS: Four hundred and three adolescents answered a questionnaire evaluating sleep bruxism (SB) and awake bruxism (AB). Parents/caregivers answered a questionnaire evaluating the adolescents' sleep features (drooling on the pillow, snoring). Adolescents' facial (dolichofacial/brachyfacial/mesofacial) and clinical features (pain in masseter/temporal muscle, indentations marks on the tongue, linea alba, tooth attrition, mouth's maximum opening and masseter electrical activity) were evaluated. Multinomial regression was performed. Odds ratio (OR) and confidence intervals (CI) were provided. RESULTS: Brachyfacial adolescents were less likely to present possible AB compared to mesofacials (OR=0.46, CI=0.21-0.98). Brachyfacial adolescents were more likely to present pain in the temporal muscle (OR=6.59, CI=2.18-19.87) and a higher number of posterior teeth with attrition (OR=1.25, CI=1.02-1.57) compared to mesofacials. Dolichofacial adolescents were more likely of not presenting pain in the masseter muscle (OR=2.23, CI=1.03-4.83), had a higher mouth's maximum opening (OR=1.43, CI=1.04-1.97), had a higher number of posterior teeth with attrition (OR=1.17, CI=1.00-1.37) and were more likely to drool on the pillow (OR=2.05, CI=1.15-3.67) compared to mesofacials. Dolichofacial adolescents were more likely of not presenting pain in the temporal muscle (OR=6.36, CI=2.30-17.54), to present themselves without marks on the tongue (OR=2.26, CI=1.09-4.69) and present a higher mouth's maximum opening (OR=2.09, CI=1.40-3.13) compared to brachyfacials. CONCLUSION: Bruxism and its clinical features differ among dolichofacial, brachyfacial and mesofacial adolescents.

Efecto del entrenamiento muscular masticatorio en el desarrollo del patrón vertical facial en niños: revisión narrativa / Training effect of the masticatory muscles in the development of the vertical facial pattern in children: narrative review

RESUMEN: Introducción: El patrón de crecimiento facial se establece antes de la aparición del primer molar permanente. Un exceso de crecimiento vertical facial, corresponde a individuos de cara larga, con ángulos goniacos abiertos, alturas faciales inferiores aumentadas y músculos masticatorios de menor área transversal. Esto se asocia a presentar mordida abierta anterior, mordida cruzada, clase II esquelético, entre otros. El entrenamiento muscular masticatorio podría controlar el excesivo crecimiento vertical, generando fuerzas opuestas que favorezcan un crecimiento horizontal. Objetivo: Describir el efecto del entrenamiento muscular masticatorio en el desarrollo del patrón vertical facial en niños. Método: Se realizó una revisión narrativa mediante búsqueda electrónica en las bases de datos PubMed, EBSCO, Scopus, Cochrane, Trip Database y Epistemonikos. Se utilizaron las palabras clave: "músculos masticatorios", "maseteros", "temporales", "masticación", "ejercicio", "entrenamiento", "crecimiento vertical", "patrón vertical", "dolicofacial", "control vertical". Los términos MeSH: "músculos masticatorios", "ejercicio". Resultados: Se seleccionaron 15 artículos de los cuales 9 son ensayos clínicos, 4 son reportes de caso y 2 son estudios observacionales transversales. Conclusiones: El entrenamiento muscular masticatorio tiene efectos positivos, favoreciendo un mayor crecimiento horizontal en niños con patrón vertical. No obstante, faltan estudios y ensayos clínicos para establecer y cuantificar los cambios morfológicos generados por el entrenamiento muscular.

ABSTRACT: Background: The pattern of facial growth is established before the eruption of the first permanent molar. An excess of vertical facial growth corresponds to individuals with long faces, open gonial angles, higher inferior facial heights and smaller masticatory muscles associated with different dental anomalies like anterior open bite, Brodie bite, skeletal class II and others. The masticatory muscle training could control the excessive growth in the vertical dimension, making opposing forces that will favor the horizontal growth in the patient. Objective: Describe the effect of the masticatory muscle training in the development of the vertical pattern in children. Method: A narrative review was done by an electronic research in PubMed, EBSCO, Scopus, Cochrane, Trip Database y Epistemonikos. The following key words were used: "masticatory muscles", "masseter", "temporalis", "mastication", "chewing", "exercise", "training", "vertical growth", "vertical pattern", "dolichofacial", "vertical control". The MeSH terms: "masticatory muscles", "exercise". Results: Fifteen articles were selected, 9 of them were clinical trials, 4 were case reports and 2 were observational studies. Conclusions: The literature review shows that the masticatory muscle training has positive effects, favoring the horizontal growth in children with vertical facial pattern. Nevertheless, there is a lack of studies and clinical trials, that could help us to establish and quantify the morphological changes made by the masticatory muscle training.

Associação entre tipo facial, possível bruxismo do sono e em vigília e características clínicas em adolescentes / Association among facial type, possible sleep bruxism and awake bruxism and clinical characteristics in adolescents

As características dos músculos faciais, a variação do formato e a configuração facial, tanto no sentido vertical como no sentido horizontal, determinam a classificação de tipo facial. Observar o tipo facial é importante, pois indivíduos com diferentes tipos faciais apresentam características próprias. O objetivo deste estudo foi avaliar a ocorrência do bruxismo do sono e em vigília e suas características clínicas entre adolescentes dolicofaciais, braquifaciais e mesofaciais. Quatrocentos e três indivíduos participaram. O tipo facial dos adolescentes (dolicofacial, braquifacial ou mesofacial) foi determinado através do Índice facial. O possível bruxismo do sono e em vigília foram avaliados por meio de um questionário de auto relato. As características clínicas dor nos músculos temporal e masseter, ronco, hábito de babar no travesseiro, marcas na língua, linha alba, desgaste em dentes anteriores, desgaste em dentes posteriores, máxima abertura de boca e atividade elétrica do músculo masseter também foram avaliadas. Foi realizada estatística descritiva e regressão multinomial. Os resultados foram expressos em odds ratio (OR) e intervalos de confiança (IC). Entre os 403 adolescentes, 234 (58,1%) eram do sexo feminino e 169 (41,9%) do sexo masculino. Em relação ao tipo facial, a maioria dos adolescentes apresentou o tipo dolicofacial (54,3%), seguido pelos adolescentes mesofaciais (26,1%) e aqueles que apresentaram o tipo braquifacial (19,6%). A média de idade dos adolescentes foi de 14,36 anos (±1,56). Adolescentes braquifaciais tinham menos chances de apresentarem possível bruxismo em vigília (algumas vezes) em comparação aos adolescentes mesofaciais (OR=0,45, IC=0,210,98). Adolescentes braquifaciais tinham mais chances de apresentarem dor no músculo temporal (OR=6,58, IC=2,17-19,93) e um número maior de dentes posteriores com desgaste (OR=1,24, IC=1,02-1,52) em comparação aos adolescentes mesofaciais. Adolescentes dolicofaciais tinham mais chances de não apresentarem dor no músculo masseter (OR=2,21, IC=1,02-4,79), de apresentarem um maior ângulo de abertura de boca (OR=1,58, IC=1,13-2,20), um número maior de dentes posteriores com desgaste (OR=1,17, IC=1,00-1,38) e babar no travesseiro algumas vezes (OR=2,06, IC=1,15-3,68) em comparação aos adolescentes mesofaciais. Adolescentes dolicofaciais tinham mais chances de não apresentarem dor no músculo temporal (OR=5,73, IC=2,12-15,49), de não apresentarem marcas de edentação na língua (OR=2,23, IC=1,08-4,57) e de apresentarem um maior ângulo de abertura de boca (OR=2,18, IC=1,46-3,24) quando comparados a adolescentes braquifaciais. O bruxismo e suas características clínicas diferiram entre adolescentes dolicofaciais, braquifaciais e mesofaciais.

The characteristics of the facial muscle, the variation of the shape of the face, both vertically and horizontally, determine the facial type of an individual. Diagnosis of the facial type and its associated features is important, since individuals with different facial types have their own characteristics. The objective of this study was to compare the occurrence of sleep and awake bruxism and their associated clinical characteristics among dolichofacial, brachyfacial and mesofacial adolescents. Four hundred three individuals participated. Adolescents? facial type (dolichofacial, brachyfacial or mesofacial) was determined. Possible sleep and awake bruxism were assessed. The clinical characteristics pain in the masseter and in the temporal muscle, snoring, drooling on the pillow, indentations marks on the tongue, linea alba on the inner cheek, attrition in anterior teeth, attrition in posterior teeth, maximum opening of the mouth and electrical muscle activity were also evaluated. Descriptive statistics and multinomial regression were performed. Results were provided in odds ratio (OR) e confidence intervals (CI). Among the 403 adolescents, 234 (58.1%) were female individuals and 169 (41.9%) were male individuals. As regards the facial type, most adolescents presented a dolichofacial facial type (54.3%), followed by adolescents with mesofacial facial type (26.1%) and those presenting a brachyfacial facial type (19.6%). Adolescents? mean age was 14.36 years. Brachyfacial adolescents were less likely to present possible awake bruxism compared to mesofacial adolescents (OR=0.45, CI=0.21-0.98). Brachyfacial adolescents were more likely to present pain in the temporal muscle (OR=6.58, CI=2.17-19.93) and a higher number of posterior teeth with attrition (OR=1.24, CI=1.02-1.52) compared to mesofacial adolescents. Dolichofacial adolescents were more likely of not presenting pain in the masseter muscle (OR=2.21, CI=1.02-4.79), had a greater maximum opening of the mouth (OR=1.58, CI=1.13-2.20), had a higher number of posterior teeth with attrition (OR=1.17, CI=1.00-1.38) and were more likely to drool on the pillow sometimes (OR=2.06, CI=1.15-3.68) compared to mesofacial adolescents. Dolichofacials adolescents were more likely of not presenting pain in the temporal muscle (OR=5.73, CI=2.12-15.49), to present themselves without marks on the tongue (OR=2.23, CI=1.08-4.57) and with a greater maximum opening of the mouth (OR=2.18, CI=1.46-3.24) compared to brachyfacial adolescents. Bruxism and its clinical characteristics differ among dolichofacial, brachyfacial and mesofacial adolescents.

Short-term dentoskeletal changes following Class II treatment using a fixed functional appliance: the Austro Repositioner : A pilot study.

OBJECTIVE: Purpose of this prospective study was to evaluate the skeletal and dentoalveolar effects of a fixed functional appliance, the Austro Repositioner, in dolicho- and brachyfacial skeletal Class II patients. MATERIAL AND METHODS: In all, 20 dolicho- and 25 brachyfacial consecutive patients treated with the Austro Repositioner were compared with untreated controls (20 dolicho- and 20 brachyfacial patients) with the same initial dentoskeletal features. Lateral cephalograms were acquired before and 1.0±0.2 year after therapy. RESULTS: Significant improvements in skeletal Class II relationships were observed in both groups. The ANB angle decreased (3.56° in dolicho- and 3.13° in brachyfacial patients, P < 0.001) due to changes localized exclusively in the mandible, the SNB angle increased to 3.20° in dolicho- and 3.02° in brachyfacial patients, and the total mandibular length (Co-Pg) increased to 6.47 mm in dolicho- and 5.78 mm in brachyfacial patients (P < 0.001). A favorable guidance of vertical pattern was also achieved in both groups, and no significant changes were observed in the upper and lower incisors in both groups. CONCLUSIONS: The Austro Repositioner was effective for short-term treatment of skeletal Class II malocclusion resulting from the retrusion of the mandible in both dolicho- and brachyfacial patients.

Applicability of the Moyers' Probability Tables in Adolescents with Different Facial Biotypes.

INTRODUCTION: The Moyers' probability tables are used in mixed dentition analysis to estimate the extent of space required for the alignment of canines and premolars, by correlating the mesiodistal size of lower incisors with the size of permanent canines and premolars. OBJECTIVE: This study intended to evaluate the applicability of the Moyer's probability tables for predicting the mesiodistal space needed for the correct location of premolars and permanent canines non-erupted, in adolescents of the city of Cordoba, Argentina, who show different facial biotypes. MATERIALS AND METHODS: Models and tele-radiographies of 478 adolescents of both genders from 10 to 15 years of age were analyzed. The tele-radiographies were measured manually in order to determine the facial biotype. The models were scanned with a gauged scanner (HP 3670) and measured by using Image Pro Plus 4.5 software. RESULTS: According to this study, the comparison between the Moyer´s probability table, and the table created at the National University of Córdoba (UNC) (at 95%, 75%, and 50%) shows that, in both tables, a higher value of mesiodistal width of lower incisors corresponds to a bigger difference in the space needed for permanent canines and premolars; being the need for space for permanents canines and premolars bigger in the UNC´s table. On the other hand, when contrasting the values of mesiodistal space for permanent canines and premolars associated with each facial biotype, the discrepancies between groups were not statistically significant (P >0.05). However, we found differences in the size of the space required according to the mesiodistal width range of the lower incisors for each biotype: a) The comparison of lower-range values, with a mesialdistal width of lower incisors less than 22 mm, the space required for permanent canines and premolars resulted smaller in patients with dolichofacial biotype than in patients with mesofacial and braquifacial biotypes. The latter biotypes have meager differences between them. b) The comparison of mid-range values, with a mesialdistal width of lower incisors from 22 to 25 millimeters, shows that the values of required alignment space are similar in the three facial biotypes. c) Finally, the comparison of upper range values, with a mesialdistal width of lower incisors greater than 25 millimeters, indicates that the space required for dolichofacial biotypes tends to be higher than in mesofacial and brachyfacial biotypes. CONCLUSION: The Moyer´s probability tables should be created to meet the needs of the population under study, with no consideration of patients' facial biotypes.

Extracciones de primeros premolares simétricos en paciente con apiñamiento severo: Reporte de un caso

Cuando se presenta apiñamiento severo, en muchas ocasiones la ubicación que adoptan las estructuras dentarias dificultan el tratamiento, por lo cual se sugiere extracciones asimétricas para permitir de esta manera un tratamiento menos prolongado y con resultados satisfactorios. En este artículo se reporta un caso de biprotrusión dentaria tratado con extracciones de 4 premolares, en una paciente femenina de 20 años y 6 meses, Clase II esquelética, hiperdivergente, con un patrón dolicofacial, Clase III molar bilateral, Clase I canina bilateral, línea media superior coincidente e inferior 4 mm desviada a la izquierda, y no presenta hábitos. En los objetivos de tratamiento se planteó: extracciones asimétricas de primeros premolares superiores e inferiores, corregir el apiñamiento maxilar y mandibular, obtener líneas medias coincidentes, obtener la Clase I molar bilateral, mantener la Clase I canina bilateral. Se logró corregir el apiñamiento severo con una forma de arco adecuada.

In cases of severe crowding, many times the location of dental structures impede treatment, so asymmetrical extractions is suggested to allow a less prolonged treatment with satisfactory results. This article presents a case of dental extractions biprotrution treated with 4 premolars reported, a case of 20 years and 6 months old female patient, skeletal Class II, hyperdivergent, with bilateral dolichofacial pattern, molar Class III bilateral, canine Class I bilateral, upper midline coincident and lower midline 4mm left deviated, is reported and no habits. The goals of treatment are proposed: a symmetric extractions of first premolars upper and lower, correct the maxillary and mandibular crowding, achieve midlines, and obtain bilateral Class I molar and maintain bilateral Class I canine. It was possible to correct severe crowding with a suitable form of arch.

Biomechanical potential of the temporal muscle in brachyfacial and dolichofacial subjects: a study on dry mandibles.

OBJECTIVES: To measure the lengths of the force and resistance arms, in order to calculate the mechanical advantage and muscular work of the human temporalis muscle (TM) in brachyfacial (BR) and dolichofacial (DO) subjects. SETTING AND SAMPLE POPULATION: Mandibles from 49 subjects of both genders (BR n = 9; DO n = 40) from the collection of the Laboratory of Human Anatomy at Universidade de Santa Cruz do Sul, Rio Grande do Sul, Brazil, were analyzed. MATERIAL AND METHODS: The distance between the condylar process and the coronoid process (insertion site of the TM) represented the length of the force arm (LFA ) of the TM. The distance between the condylar process and the mental protuberance represented the length of the resistance arm (LRA ). Thus, the mechanical advantage of the TM was obtained using the following ratio: LFA /LRA , while the muscular work (LRA /LFA ) of the TM was obtained using the inverse of this ratio. RESULTS: When compared with the DO, the parameters of the BR are significantly greater, as shown by the LFA (6.0%) and mechanical advantage (8.2%; p = 0.0078). By contrast, our results show that in the DO, the LRA was 2.4% longer and the muscular work was 10.4% greater (p = 0.0087). CONCLUSION: The mechanical advantage of the TM in BR subjects is significantly greater than in DO subjects. Moreover, this greater mechanical advantage may explain, at least in part, the higher incidence of temporomandibular dysfunctions in BR subjects.

Median mandibular flexure at different mouth opening and its relation to different facial types: A prospective clinical study.

OBJECTIVE: To measure the arch width and Median mandibular flexure (MMF) values at relative rest and maximum jaw opening in young adults with Dolichofacial, Mesofacial, and Brachyfacial types and tested whether the variation in the facial pattern is related to the MMF values in South Indian population. MATERIALS AND METHODS: This Prospective clinical study consisted of sample of 60 young adults. The subjects were grouped into 3 groups: Group 1: Brachyfacial, Group 2: Mesofacial and types, Group 3: Dolichofacial. Impressions were taken for all the 60 subjects and the casts were scanned and digitized. The intermolar width was measured for Dolichofacial, Mesofacial, and Brachyfacial subjects at relative rest (R) and maximum opening (O). RESULTS: The statistical analysis of the observations included Descriptive and Inferential statistics. The statistical analysis was executed by means of Sigma graph pad prism software, USA Version-4. Kruskal wallis (ANOVA) followed by Dunns post hoc test was performed. Mann Whitney U-test was performed to assess the difference in MMF values between Males and Females of the three groups. The Mean (SD) Mandibular flexure in individuals with Brachyfacial type was 1.12 (0.09), Mesofacial type was 0.69 (0.21), and Dolichofacial type was 0.39 (0.08). CONCLUSIONS: The Mean intermolar width was maximum in Brachyfacial type and minimum in Dolichofacial type. MMF was maximum at the maximum mouth opening position and was maximum in individuals with Brachyfacial type.

Avaliação da alteração do plano oclusal em pacientes dolicofaciais portadores de classe II mandibular que utilizaram o aparelho Bionator de Balters / Evaluation of occlusal plane changes in dolichofacial patients with mandibular class II malocclusion after Balters Bionator therapy

Objetivo: avaliar cefalometricamente a influência do Bionatorde Balters no plano oclusal em pacientes dolicofaciais portadoresde maloclusão de Classe II de Angle associadas ao retrognatismomandibular, durante a fase de crescimento. Metodologia:a amostra consistiu de 40 telerradiografias obtidas em doistempos (T1: inicial; T2: após bionatorterapia) de 20 pacientes,sendo 10 do sexo masculino e 10 do sexo feminino com idadesvariando entre 7 e 15 anos (média de 9,03). Resultados e Conclusões:constatou-se um controle bastante eficiente da inclinaçãodo plano oclusal, provocando sua rotação anti-horária, o que éconsiderado essencial na estabilidade dos resultados.

Aim: the purpose of this study is a cephalometric evaluationof the influence of the Balters Bionator on the occlusal plane indolichofacial patients with mandibular Class II malocclusionduring growth period. Methods: the sample comprised of 40 lateralcephalograms taken at two times (T1: initial; T2: after bionatortherapy)from 20 patients, 10 females and 10 males withage ranging between 7 and 15 years (average 9,03). Results andconclusions: an efficient control of the occlusal plane inclinationwas evidenced resulting counter clockwise rotation which wasessential for the achievement and stability of the results.