Nasomaxillary and mandibular bone growth in primary school girls aged 7 to 12 years

BACKGROUND/PURPOSE: Facial bone growth manifests in primary school-aged children, especially girls. This study investigated the changes in nasomaxillary and mandibular morphology of primary school girls. MATERIALS AND METHODS: Cephalograms of 60 primary school girls were divided into 3 groups (group I, aged 7–8 years; group II, aged 9–10 years; and group III, aged 11–12 years). The dimensions of the nasomaxilla (nasal bone length, nasal ridge length, nasal depth, palatal length, and maxillary height) and mandible (condylar length, condylar width, coronoid length, coronoid width, ramus length, body length, symphysis length, and entire mandibular length) were measured. One-way ANOVA and Pearson's correlation coefficient were used for statistical analysis. RESULTS: Nasal ridge length, nasal depth, and maxillary height were significantly greater in group III than in group I and group II. Condylar width and body length were significantly greater in group III than in group I and group II. Pearson's correlation revealed significant positive correlations between age and nasal ridge length, nasal depth, or maxillary height. There were also significant positive correlations between age and ramus length, body length, or entire length of the mandible. CONCLUSION: We found that nasal ridge length, nasal depth, maxillary height, condylar width and body length were significantly greater in group III than in group I or in group II. Moreover, there were significant correlations between age and the nasal ridge length, nasal depth, maxillary height, ramus length, body length, or entire length of the mandible.