Cranial base growth for Dutch boys and girls: a multilevel approach.

Growth of the cranial base in Dutch children who had undergone orthodontic treatment and children who had not is described and compared with the aid of multilevel statistical techniques. Growth changes of the cranial base (S-N, N-Ba, and S-Ba) were evaluated. The results pertain to a mixed longitudinal sample of 153 boys and 167 girls for S-N and 116 boys and 116 girls for N-Ba and S-Ba, 7 to 14 years of age. No significant difference could be demonstrated between subjects who had received orthodontic treatment and subjects who had not. The cranial base displayed sexual dimorphism in the timing and amount of growth. All dimensions measured in girls were significantly smaller than in boys (p < 0.05). No adolescent growth spurts were found in girls; boys showed adolescent growth spurts for S-N and N-Ba. Adolescent growth velocities were significantly greater for boys than for girls.

Influence of oral hygiene on early enamel caries.

For 548 children aged 4-16 years, mean (+/- SD) age 10.3 +/- 2.7 at visit 1, the dental status was recorded at four consecutive 6-monthly visits. Simultaneously oral hygiene was scored according to a modified patient hygiene performance (PHP) index after application of disclosing solution and before the dental examination. The following cariogenic changes could be observed: initiation (white spot formation), progression (cavitation), stabilisation and regression (disappearance of a white spot). The PHP score was examined in relation to these changes in smooth surfaces, as well as in fissures. For fissures when oral hygiene worsened, stabilisation of a white spot increased significantly. Also, regression of a white spot into sound enamel increased with poor oral hygiene, but the significance was only marginal. White spots turning into cavities, however, did not change with poor oral hygiene. It was speculated that under low oral hygiene conditions the remaining plaque of children receiving intensive fluoride treatment can bind fluoride to the fissure surfaces, thereby promoting enamel maturation concomitant with stabilisation and regression of white spots, which in an earlier study were also found to be dependent on posteruptive age.