Angle Class II, Division 2 Malocclusion and Association with Late Eruption

Objective: To verify the dental age of individuals with Angle Class II, division 2 malocclusion. Material and Methods: The sample consisted of 200 panoramic radiographs of schoolchildren from the city of Fortaleza in the state of Ceará, in the northeast of Brazil. These radiographs were divided into two groups (N=100): a Control group comprising radiographs of patients with normal occlusion and a CIID2 group comprising radiographs of patients with an Angle Class II, division 2 malocclusion. The Demirjian method was used to identify dental age. All the radiographs were evaluated by a sole duly trained and calibrated technician. The Kappa coefficient for inter-annotator agreement was 0.98 based on the criteria of eruption stage of each tooth. Statistical analysis was performed using the Chi-squared test, Student's t-test and the Mann-Whitney test, with a level of significance of 5%. Results: There was a significant statistical difference between the dental ages of the groups tested. The CIID2 group had a lower dental age than the control group, signifying late eruption in patients with an Angle Class II, division 2 malocclusion. Conclusion: Patients with an Angle Class II, division 2 malocclusion had a lower dental age than patients with normal occlusion, suggesting that orthodontic treatment should be delayed. The first molars, second pre-molars and canines suffered late eruption.

Características oclusais de bebês com microcefalia associada ao vírus Zika / Occlusal characteristics of babies with microcephaly associated with the Zika virus

Introdução: A microcefalia em um nascido vivo é definida como uma anomalia em que perímetro cefálico (PC) está abaixo do padrão de curvas apropriadas para idade e gênero. A etiologia pode envolver anormalidades genéticas, síndromes, distúrbios metabólicos, teratógenos, infecções pré-natal, perinatal e pós-natal. Porém, essa malformação tornouse muito mais prevalente com o surto recente do vírus Zika. Objetivos: Estudar o padrão de oclusão em bebês com microcefalia associada ao vírus Zika (MZV). Metodologia: O artigo 1 foi um estudo transversal que incluiu pacientes com diagnóstico de MZV (40) entre 30 e 36 meses e um grupo controle com bebês saudáveis (40), aleatoriamente selecionadas com as mesmas características sociodemográficas. A análise estatística utilizou análise descritiva, o teste qui-quadrado de Pearson e a regressão logística multivariada. O artigo 2 foi um relato de casos clínicos com infecção no segundo trimestre da gestação. O artigo 3 foi um relato de casos clínicos com infecção no primeiro trimestre da gestação. Resultados: Foi demonstrado uma prevalência significativamente maior de maloclusões em bebês MZV em comparação ao grupo controle (artigo 1). Pacientes com MZV possuíram maior probabilidade de apresentar irrupção tardia (p < 0,001), formato da arcada superior e inferior atrésico (p < 0,001), overjet acentuado (p < 0,001) e mordida cruzada posterior (p= 0,004) (artigo 1). Também foi demostrado ocorrência de irrupção tardia, hipodontia, tendência a crescimento vertical, perfil convexo, comprometimento do tônus muscular, incompetência de selamento labial, mordida aberta e desvio de linha média (artigos 2 e 3). Conclusões: Conclui-se que existe uma maior probabilidade de irrupção tardia e prevalência maior de maloclusões em bebês MZV, dentre elas o formato da arcada superior e inferior atrésico, overjet acentuado e mordida cruzada posterior. Comprometimento muscular também foi encontrado. Além disso, o período de infecção pelo vírus parece determinar a gravidade das características encontradas (AU).

Introduction: Microcephaly in a live birth is defined as an anomaly in which head circumference (HC) is below the standard for age and gender appropriate curves. The etiology may involve genetic abnormalities, syndromes, metabolic disorders, teratogens, prenatal, perinatal and postnatal infections. However, this malformation has become much more prevalent with the recent emergence of the Zika virus. Objectives: To determine the prevalence of malocclusion among infants with Zika virus-associated microcephaly (MZV) and to describe the most common malocclusion characteristics in this population (Article 1); to identify differences in univiteline twins with and without Zika virus-associated microcephaly infection during the second trimester of gestation (Article 2); to describe the dentoskeletal changes in two infants who were infected with the Zika virus during the first trimester of gestation (Article 3). Method: Article 1 was a cross-sectional study which included patients diagnosed with MZV (40) between 30 and 36 months and a comparison group with healthy babies (40), randomly selected with the same sociodemographic characteristics. The statistical analysis used descriptive analysis, Pearson's chi-squared test and multivariate logistic regression. Articles 2 and 3 are case reports, one with infection in the second trimester of pregnancy and another in the first, respectively. Results: In article 1, a significantly higher prevalence of malocclusions in MZV infants was demonstrated in comparison to the control group (p<0.001). Patients with MZV were more likely to have late eruption (p<0.001), atresic upper and lower arch (p<0.001), marked overjet (p<0.001), and posterior crossbite (p=0.004). In article 2, muscular impairment was the most striking feature for the twin with microcephaly. In article 3, late eruption, hypodontia, tendency to vertical growth, convex profile, muscle tone impairment, incompetence to seal the lips, open bite, midline deviation and atresic arches were demonstrated. Conclusions: It is concluded that there is a greater probability of late eruption and higher prevalence of malocclusions in MZV infants, with atresic upper and lower arch, overjet and posterior crossbite among them (Article 1). In addition, the infection period of the virus seems to determine the severity of the characteristics found: less occurrence of dental problems and maintenance of neuromuscular changes can be determined when in the second trimester (Article 2); but when infection occurs in the first trimester, dento-skeletal impairment is greater along with the associated functional alterations (Article 3) (AU).