[Three dimensional measurement of craniofacial hard tissues for the Han nationality with normal occlusion in Changsha area].

OBJECTIVE: To explore the influence of gender and age on the measurement of cone beam CT (CBCT) in normal and occluded craniofacial hard tissues for Han nationality in Changsha area.
 Methods: A total of 80 CBCT data of normal and occluded craniofacial hard tissues for Han nationality in Changsha area were collected, including 40 adults [16 males and 24 females, aged (17.57±1.83) years] and 40 children[16 males and 24 females, age (11.50±1.26) years]. Three-dimensional cephalometric measurements were carried out by Dolphion Imaging software, and the influence of gender and age was compared.
 Results: The symmetry of craniofacial hard tissues in male and female in the adults was good (the maximum asymmetric rate R was 6.39% and the minimum asymmetric rate R was 0.08%). There was no significant differencein the anterior palatal width, palatal width, the upper incisor protrusion distance, the lower incisor protrusion distance, hyoid-mandibular plane, basal epiglottis width, and palatal plane airway width between the males and females (all P>0.05); while the remaining indicators were significantly higher in males than those in females (all P<0.05). There was no significant gender difference in angle indicators (all P>0.05). There were significant differences in the posterior height, the maxillary length, the lower incisor protrusion, and the mandibular plane angle between the adults and the children(all P<0.05); but the rest of indicators were not significant difference (all P>0.05).
 Conclusion: The symmetry of craniofacial hard tissues for Han nationality in Changsha area is good. The gender and age affect the line space measurements but not affect the most of the angle measurements.

[Correlation between adenoid hypertrophy, maxillary sinus mucosal thickening and dentofacial development in children].

PURPOSE：To investigate the effects of adenoid hypertrophy and maxillary sinus mucosal thickening on dentofacial development. METHODS：The selected subjects were divided into 4 groups according to the inclusion criteria: group A (adenoid hypertrophy with maxillary sinus mucosal thickening), group B (adenoid hypertrophy without maxillary sinus mucosal thickening), group C (normal adenoid with maxillary sinus mucosal thickening), and group D (normal adenoid without maxillary sinus mucosal thickening). There were 20 subjects in each group, aging from 12 to 14 years old. The volume of maxillary sinus was measured by Mimics software. The adenoid, dental arch width, basal bone width and palatal height were measured by Dolphin software and dentofacial measurements were performed in the lateral cephalograms derived from cone-beam CT (CBCT). The data were analyzed with SPSS 24.0 software package. RESULTS： There was no significant difference in dentofacial measurements between group B and group D or group C and group D，except for ANB angle (P<0.05). Compared with group D, SNB, ANB, Wits appraisal, NA-APo, MP-HP, N-Me, S-Go/N-Me, N-ANS (perp HP), sum of three angles, Ar-Go of group A were significantly different (P<0.05). Neither left nor right maxillary sinus bony volume had significant difference between group B and D or group C and D. CONCLUSIONS： Both adenoid hypertrophy and maxillary sinus mucosal thickening have impact on dentofacial development. Moderate or more severe adenoid hypertrophy with maxillary sinus mucosal thickening has greater impact on dentofacial development over adenoid hypertrophy or maxillary sinus mucosal thickening alone.