Dental and minor physical anomalies in children with developmental disorders--a discriminant analysis

A discriminant analysis was performed in a sample of 303 children with developmental disorders (DD) and 303 healthy controls (C) in order to test whether some oro-dental and physical minor anomalies could discriminate these groups of children. DD sample comprised 176 mentally retarded (MR) children. 70 children with impaired hearing (IH) and 57 children with impaired vision (IV). The control group included 303 healthy subjects, matched for sex and age. The analysis comprised seven common oral and dental anomalies: median diastema, hypodontia, impacted teeth, microdontia, dens invaginatus, upper lip frenulum and frenulum of the tongue. Minor physical anomalies were assessed by the method proposed by Waldrop et al., as the average number of minor anomalies per individual (W1) and as the weighted score of minor anomalies (W2). Three discriminant functions were obtained by analysis of nine initial variables. Distinct discrimination and considerable distances were found between the centroids of the controls and all groups of DD children. The first two discriminant functions were significant for discrimination between the groups and they explained 98.6% of the total variance. The first function contained 90.2% of information and was defined by the number and weighted scores of minor anomalies. The second variable explained 8.4% of the total variability and was defined by three dental anomalies. The results obtained by the discriminant analysis show that application of dental and minor physical anomalies enables discrimination between the group of healthy children and the groups of children with different developmental disorders.