Craniofacial characteristics of Caucasian and Afro-Caucasian Brazilian subjects with normal occlusion

OBJECTIVE: The objective of this study was to compare the skeletal, dental and soft tissue characteristics of Caucasian and Afro-Caucasian Brazilian subjects with normal occlusion and to evaluate sexual dimorphism within the groups. MATERIAL AND METHODS: The sample comprised lateral cephalograms of untreated normal occlusion subjects, divided into 2 groups. Group 1 included 40 Caucasian subjects (20 of each sex), with a mean age of 13.02 years; group 2 included 40 Afro-Caucasian subjects (20 of each sex), with a mean age of 13.02 years. Groups 1 and 2 and males and females within each group were compared with t tests. RESULTS: Afro-Caucasian subjects presented greater maxillary protrusion, smaller upper anterior face height and lower posterior face height, larger upper posterior face height, greater maxillary and mandibular dentoalveolar protrusion as well as soft tissue protrusion than Caucasian subjects. The Afro-Caucasian female subjects had less mandibular protrusion and smaller total posterior facial height and upper posterior facial height than males. CONCLUSIONS: Brazilian Afro-Caucasian subjects have greater dentoalveolar and soft tissue protrusion than Brazilian Caucasian subjects, with slight sexual dimorphism in some variables

Estabilidade do tratamento de apinhamento anterossuperior

OBJECTIVE: To evaluate the stability and the relapse of maxillary anterior crowding treatment on cases with premolar extraction and evaluate the tendency of the teeth to return to their pretreatment position. METHODS: The experimental sample consisted of 70 patients of both sex with an initial Class I and Class II maloclusion and treated with first premolar extractions. The initial mean age was 13,08 years. Dental casts' measurements were obtained at three stages (pretreatment, posttreatment and posttreatment of 9 years on average) and the variables assessed were Little Irregularity Index, maxillary arch length and intercanine. Pearson correlation coefficient was used to know if some studied variable would have influence on the crowding in the three stages (LII1, LII2, LII3) and in each linear displacement of the Little irregularity index (A, B, C, D, E) in the initial and post-retention phases. RESULTS: The maxillary crowding relapse ( LII3-2) is influenced by the initial ( LII1), and the teeth tend to return to their pretreatment position. CONCLUSION: The results underline the attention that the orthodontist should be given to the maxillary anterior relapse, primarily on those teeth that are crowded before the treatment

Maxillary anterior crowding relapse in class I and II extraction treatment

A estabilidade pós-tratamento sempre foi um assunto delicado da ortodontia. A maioria dos pacientes e até mesmo os ortodontistas, julgam o sucesso do tratamento ortodôntico pela estabilidade dos resultados em longo prazo. Por este motivo a literatura é repleta de estudos acerca deste assunto, principalmente da recidiva do apinhamento ântero -inferior. Já o interesse pelo apinhamento ânterosuperior e sua recidiva é crescente por conta de uma maior preocupação com a estética do sorriso. Desta forma, o propósito deste estudo é comparar a recidiva do apinhamento ântero-superior em pacientes com má oclusão de Classe I e Classe II de Angle. A amostra consiste em 70 pacientes divididos em 3 grupos. O Grupo 1 apresenta 30 pacientes (12 do gênero masculino e 18 do gênero feminino) com má oclusão de Classe I, idade média inicial de 13,16 anos e tratados com extrações dos 4 primeiros pré -molares. O Grupo 2 apresenta 20 pacientes (11 do gênero masculino e 9 do gênero feminino) com má oclusão de Classe II divisão 1, idade média inicial de 12,95 anos e também tratados com extrações dos 4 primeiros pré-molares. O Grupo 3 apresenta 20 pacientes (11 do gênero masculino e 9 do gênero feminino) com má oclusão de Classe II divisão 1, idade média inicial de 13,09 anos e tratados com extrações dos 2 primeiros pré -molares superiores. Foram avaliados os modelos de estudo nas fases inicial (T1), final (T2) e no mínimo 5 anos pós -tratamento (T3) de cada pac iente. As variáveis do arco superior avaliadas e comparadas estatisticamente pela Análise de Variância (ANOVA) foram: Índice de Irregularidade de Little superior (IRLS), comprimento do arco (CAS), distância intercaninos (DICS), interpré-molares (DI2PMS) e intermolares (DIMS). Como os resultados entre os grupos não mostraram diferenças estatisticamente significantes nas fases avaliadas, a amostra foi unificada. O Teste de Correlação de Pearson e o Teste de Regressão Linear Múltipla foram utilizados para veri ficar se alguma variável estudada teria influência sobre o apinhamento nas três fases (IRLS1, IRLS2, IRLS3). Os resultados mostraram que a recidiva do apinhamento superior (IRLS3-2) é influenciada pelo apinhamento inicial (IRLS1) e que os dentes tendem a voltar à posição original. O gênero feminino apresentou mais recidiva do apinhamento ântero -superior que o gênero masculino.The posttreatment stability was always a delicate issue in Orthodontics. Most of the orthodontic patients and even the orthodontists judge their treatment as successful based on the treatment outcomes stability in the long-term. Because of this reason the literature has a lot of studies about this issue, mostly on relapse of mandibular anterior crowding. However the interest on maxillary anterior crowding and its relapse has been growing because of the greater conscious on smile esthetic among patients. Therefore, the purpose of this study was to compare the relapse of maxillary anterior crowding in cases presenting Angles Class I and Class II malocclusions. The experimental sample consisted of 70 patients divided into 3 groups. Group 1 comprised 30 patients (12 male; 18 female) at a mean initial age of 13.16 years, with Class I malocclusion, treated with all first premolars extraction. Group 2 comprised 20 patients (11 male; 9 female) at a mean initial age of 12.95 years, with Class II division 1 malocclusion, also treated with all first premolars extraction. Group 3 comprised 20 patients (10 male; 10 female) at a mean initial age of 13.09 years, with Class II division 1 malocclusion, treated with extraction of two maxillary first premolars. Dental casts measurements were obtained at three stages (pretreatment, posttreatment and postretention) and the variables assessed were Little Irregularity Index, maxillary arch length, intercanine, interpremolar and intermolar widths. The statistical analysis was performed by one-way ANOVA and Tukey tests if necessary (intragroup comparison) and by independent t-tests (intergroup comparison). As the results among the groups did not show statistically significant difference, the experimental sample was unified in order to inve stigate, using Pearson correlation coefficient and Multiple linear regression, if some studied variable would have influence the crowding in the three stages (IRLS1, IRLS2, IRLS3). The results showed that the maxillary crowding relapse (IRLS3-2) is influenced by the initial (IRLS1), and the teeth tend to return to their pretreatment position. The females presented more maxillary anterior crowding relapse than males

Fatores De Risco Genéticos E Psicossociais Associados À Disfunção Temporomandibular

To Identify Biopsychosocial Risk Factors For Myofascial Temporomandibular Disorders In A Brazilian Sample. The Biological Factors Encompassed 15 Polimorphisms Of Camk4, Chrm2, Esr1, Grk5, Ifrd1, Mc1r, Mtrr, Nr3c1, Oprm1 And Tph1 Genes, And The Psychosocial Factors Encompassed `Depression Symptoms", `Somatization Symptoms" And `Pain Intensity And Disability". Methods: The Sample Consisted Of 679 Participants, 272 With Myofascial Temporomandibular Disorders And 407 Controls. Axis I Of Research Diagnostic Criteria For Temporomandibular Disorders Was Used To Classify The Participants Into The Groups And Axis Ii Was Used To Classify The Psychosocial Factors. Genotyping Analysis Used Taqman" Low Density Array. Binary Logistic Regression Models Were Performed In Order To Assess The Influence Of The Genetic Factor On The Presence Of Temporomandibular Disorders And Pain Duration, The Influence Of Psychosocial Factors On The Presence Of Temporomandibular Disorders, The Influence Of `Depression And Somatization SymptomsIdentificar Em Uma Amostra Da População Brasileira Do Gênero Feminino E Masculino Fatores De Risco Biopsicossociais Para A Disfunção Temporomandibular De Origem Muscular, Sendo Os Fatores De Risco Biológico: O Estudo Genético De 15 Polimorfismos Dos Genes Camk4, Chrm2, Esr1, Grk5, Ifrd1, Mc1r, Mtrr, Nr3c1, Oprm1 E Tph1, E Os Fatores De Risco Psicossociais O Estudo Dos Sintomas De Depressão, Sintomas De Somatização E Gravidade Da Dor. Métodos: A Amostra Total Foi Composta Por 679 Brasileiros Divididos Em Dois Grupos Pelo Eixo I Do Critério De Diagnóstico Para Pesquisa Em Disfunção Temporomandibular: Caso (272 Com Disfunção Temporomandibular Muscular) E Controle (407 Sem Disfunção Temporomandibular Muscular). A Genotipagem Foi Realizada Pela Tecnologia Taqman" Low Density Array. Os Dados Psicossociais Foram Coletados Pelo Eixo Ii Do Critério De Diagnóstico Para Pesquisa Em Disfunção Temporomandibular. Os Modelos De Regressão Logística Binária Foram Montados Para Analisar A Associação Dos Fatores Genéticos Com ADados abertos - Sucupira - Teses e dissertações (2018

Metallographic analysis of the internal microstructure of orthodontic mini-implants

Effective orthodontic anchorage may be obtained by miniimplants inserted into the maxillary bones. However, the risk of miniimplant failure is one of the most important issues, especially the rupture of its structure referred to as fracture, mainly due to metal deficiencies. This study analyzed the internal microstructure of orthodontic mini-implants, ascertaining the composition of the metal to detect possible discontinuities from the surface to the core of the screws. Eighteen samples of mini-implants, of 3 different brands, were obtained. The samples were cold-embedded in methyl methacrylate polymer, and were sectioned both longitudinally (3 samples of each brand) and transversely (the other 3 screws of each brand). After preparation, the samples were observed using a light microscope at up to 2,000 x magnification. The results showed that the mini-implants thus analyzed were composed of an Alpha-Beta globular phase of titanium alloy, patterns A1 and A9 (in accordance with the "Technical Committee of European Titanium Producers"). The miniimplants did not present any defects such as bubbles, imperfections or fissures, in either longitudinal or transverse sections, in their internal microstructure. All samples met the requirements of international norms. Orthodontists must be aware of the metal composition and internal microstructure of mini-implants, to decrease the risk of fractures

Tooth-wear patterns in subjects with Class II Division 1 malocclusion and normal occlusion

Introduction: The aim of this study was to investigate the prevalence of tooth wear in adolescents with Class II malocclusion, compared with those with normal occlusion. Methods: The sample consisted of dental casts obtained from 310 subjects, divided into 3 groups: group 1, 110 subjects with normal occlusion (mean age, 13.51 years); group 2, 100 complete Class II Division 1 patients (mean age, 13.44 years); and group 3, 100 half-cusp Class II Division 1 patients (mean age, 13.17 years). Dental wear was assessed by using a modified version of the tooth-wear index. The 3 groups were compared by means of the Kruskal-Wallis and Dunn tests, considering the frequency and the severity of wear on each surface of each group of teeth. The level of statistical significance was set at 5%. Results: The normal occlusion group had statistically greater tooth wear on the palatal surfaces of the maxillary central incisors and the incisal surfaces of the maxillary canines than the corresponding surfaces in both Class II malocclusion groups. The complete and half-cusp Class II Division 1 malocclusion groups had statistically greater tooth wear on the occlusal surfaces of the maxillary second premolar and first molar, the occlusal surfaces of the mandibular premolars, and the buccal surfaces of the mandibular posterior teeth compared with the normal occlusion group. The half-cusp Class II Division 1 malocclusion group had significantly greater tooth wear on the incisal surfaces of the mandibular incisors compared with the complete Class II Division 1 malocclusion group. Conclusions: Subjects with normal occlusion and complete or half-cusp Class II Division 1 malocclusions have different tooth-wear patterns. Tooth wear on the malocclusion subjects should not be considered pathologic but rather consequent to the different interocclusal tooth arrangement. (Am J Orthod Dentofacial Orthop 2010; 137: 14. e1-14.e7

Tooth-wear patterns in adolescents with normal occlusion and Class II Division 2 malocclusion

Introduction: In this study, we investigated tooth-wear patterns in adolescents with either normal occlusion or Class II Division 2 malocclusion. Methods: The sample consisted of dental casts from 165 subjects that were divided into 2 groups: 115 normal occlusion subjects (mean age, 14.3 years) and 50 complete Class II Division 2 subjects (mean age, 13.9 years). Dental wear was assessed by using a modified version of the tooth wear index. The 2 groups were compared with the Mann-Whitney test for the frequency and severity of wear on each surface of each group of teeth. The level of statistical significance was set at 5%. Results: The normal occlusion group statistically had greater tooth wear on the incisal surfaces of the maxillary lateral incisors and the incisal surfaces of the maxillary canines than did the Class II Division 2 malocclusion group. The malocclusion group showed statistically greater tooth wear on the labial surfaces of the mandibular lateral incisors, the occlusal surfaces of the maxillary premolars and first molars, the occlusal surfaces of the mandibular premolars, the palatal surfaces of the maxillary second premolars, and the buccal surfaces of the mandibular premolars and first molars than did the normal occlusion group. Conclusions: Subjects with normal occlusion and those with complete Class II Division 2 malocclusions have different tooth-wear patterns. Tooth wear on the malocclusion subjects should not be considered pathologic but, rather, the consequence of different interocclusal arrangements. (Am J Orthod Dentofacial Orthop 2010;137:730.e1-730.e5