Association between growth stunting with dental development and skeletal maturation stage.

The aim of this study was to determine the influence of growth stunting on the maturation stage of the medium phalanx of the third finger (MP3) and the dental development of the left mandibular canine in 280 high school children (140 stunted and 140 normal controls; equally distributed by sex) between 9.5 and 16.5 years of age, from a representative Peruvian school. Periapical radiographs of the MP3 from the left hand were used to determine the skeletal maturity stage, according to an adaptation of the Hägg and Taranger method. Panoramic radiographs were used to determine the dental maturity stage of the lower left canine, according to Demirjian method. Stunting was determined by relating height and age, according to the World Health Organization recommendations. There was no statistically significant difference in the skeletal maturation stage (P = .134) and the dental development stage (P = .497) according to nutritional status, even when considering different age groups (P > .183). A high correlation (r = 0.85) was found between both maturity indicators regardless of the nutritional status (growth stunted, r = 0.855 and normal controls, r = 0.863) or sex (boys, r = 0.809 and girls, r = 0.892). When skeletal level was considered, correlations values were similar between advanced (r = 0.903) and average (r = 0.895) maturers but lower (r = 0.751) for delayed maturers. Growth stunting was not associated with dental development and skeletal maturity stages in Peruvian school children.

Sex and ethnic differences in 2nd to 4th digit ratio of children.

BACKGROUND: The ratio between the length of the 2nd or index finger and the 4th or ring finger (2D:4D) differs between the sexes, such that males have lower 2D:4D than females, and shows considerable ethnic differences, with low values found in Black populations. It has been suggested that the sex difference in 2D:4D arises early in development and that finger ratio is a correlate of prenatal testosterone and oestrogen. In children, 2D:4D has been reported to be associated with measures of fetal growth, congenital adrenal hyperplasia, developmental psychopathology, autism and Asperger's syndrome. However, little is known of the patterns of sex and ethnic differences in the 2D:4D ratio of children. AIM: To investigate sex and ethnic differences in 2D:4D in Caucasian, Oriental and Black children. STUDY DESIGN: Population survey. METHOD: The 2D:4D ratio was measured from photocopies of the right hand of Berber children from Morocco, Uygur and Han children from the North-West province of China, and children from Jamaica. RESULTS: There were 798 children in the total sample (90 Berbers, 438 Uygurs, 118 Han, and 152 Jamaicans). The 2D:4D ratio was lower in males than in females and this was significant for the overall sample and for the Uygur, Han and Jamaican samples. There were significant ethnic differences in 2D:4D. The Oriental Han had the highest mean 2D:4D, followed by the Caucasian Berbers and Uygurs, with the lowest mean ratios found in the Afro-Caribbean Jamaicans. The sex and ethnic differences were independent of one another with no significant interaction effect. In the overall sample there were no associations between 2D:4D and age and height. CONCLUSIONS: In common with adults, the 2D:4D ratio of children shows sex and ethnic differences with low values found in a Black group. There was no overall association between 2D:4D and age and height suggesting that the sex and ethnic differences in 2D:4D appear early and do not show appreciable change with growth.

Validity of the use of a few hand-wrist bones for assessing bone age.

Bone age is widely used as an osseous maturation method to assess biological development in clinical and auxological studies. Numerical methods for calculating bone age have better replicability; however, they require a wide data manipulation. The aim of this study was to evaluate the accuracy of bone age estimation by using just a few ossification centers. In 205 hand and wrist radiographs of children and adolescents, aged 0.9-17.4 years old (111 males and 94 females), bone age was determined by two trained observers employing the five-bone (B5) and the TW2 methods. To compare the results of the two methods, the mean differences by age and sex were tested by the Mann-Whitney test. The relationship of the bone age distribution estimated by B5 and TW2 was calculated and the mean of the bone age determined by the two methods was plotted by age and by differences between bone age calculated by the two methods +/- 2 SD. The bone age determined by B5 was between 1.2 and 16.8, and by TW2 was between 1.2 and 18.0 years. The mean differences between B5 and TW2 (-0.06 +/- 0.6) were not significant (p > 0.05). The distribution of mean differences by age and method demonstrated that all deviations were encompassed into +/- 2 SD with no particular bias. In general terms, a good agreement was obtained between these two methods.