OCCLUSAL CHARACTERISTICS OF INFANTS WITH MICROCEPHALY ASSOCIATED WITH THE ZIKA VIRUS
Microcephaly; Malocclusion; Deciduous Teeth.
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).