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Objective@#To investigate the three-dimensional morphological characteristics of the upper airway in children and adolescents with skeletal class Ⅲ malformation and to explore the relationship between craniofacial structure and upper airway morphology.@*Methods @#Ninety cases of malocclusion aged 3-18 years were collected. In addition, 45 cases of type I and type Ⅲ were classified into three age groups with 15 cases in each group: 3-6 years old, 7-12 years old and 13-18 years old. CBCT was taken, and the scanning data of CBCT were reconstructed by the third-party software Invivo 5. The volume, minimum cross-sectional area, height and the ratio of sagittal diameter to transverse diameter at the minimum cross-sectional area of each segment of the upper airway were measured. The difference of the upper airway between skeletal class I and skeletal class Ⅲ in each age group was analyzed and compared by group t test.@*Results @# No significant differences in the upper airway indexes were noted between skeletal class I and skeletal class Ⅲ(P > 0.05) in the 3-6 years old group. In the 7-12 years old group, the total volume of skeletal class Ⅲ upper airway (16.25 ± 3.69 cm 3), nasopharyngeal segment (2.39 ± 0.90 cm 3), and palatopharyngeal segment (5.24 ± 1.14 cm 3) were reduced compared with the total volume of the skeletal class I upper airway (20.98 ± 6.25 cm 3) , nasopharyngeal segment (4.21 ± 1.09 cm 3), and palatopharyngeal segment (8.18 ± 2.02 cm 3), respectively, the differences were statistically significant (tVtotal=2.526, tVnose=4.999, tVpalate=4.908, P < 0.05). In the 13-18 years old group, only nasopharyngeal segment volume (3.83 ± 0.90 cm 3) was reduced in skeletal type I (4.69 ± 1.34 cm 3); the difference was statistically significant (t=2.053, P < 0.05).@*Conclusion@# Age is an important factor affecting the morphology and structure of upper airway in skeletal Ⅲ malocclusion.
RESUMEN
Haploinsuffieiency of the runt-related transcription factor 2 (Runx2) gene is widely known to be responsible for cleidocranial dysplasia (CCD).To date,more than 190 mutations in Runx2 gene have been reported to be related to CCD.In this study,a novel mutation of Runx2 gene was observed in a female with CCD.Genomic DNA was extracted from peripheral venous blood of the proband and eleven members of her family.Genetic testing on these twelve people identified a novel missense mutation (c.895T＞C,Y299H) in exon 5 of the RUNX2 gene in the proband.This mutation results in an amino acid change at codon 895 (P.Tyr 299 His.) from a tryptophan codon (TAT) to a histidine codon (CAT).Our finding may further extend the known mutation spectrum of the RUNX2 gene,and facilitate prenatal genetic diagnosis of CCD in the future.