[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.

GDF11 promotes osteogenic/odontogenic differentiation of dental pulp stem cells to accelerate dentin restoration via modulating SIRT3/FOXO3-mediated mitophagy.

BACKGROUND: Growth differentiation factor 11 (GDF11) is considered to be a potential molecular target for treating pulpitis. However, whether GDF11 regulates osteogenic/odontogenic differentiation of dental pulp stem cells (DPSCs) to mediate pulpitis process remains unclear. METHODS: Lipopolysaccharide (LPS) was used to induce inflammation conditions in DPSCs. The levels of GDF11, sirtuin 3 (SIRT3), forkhead box O-3 (FOXO3), osteogenic/odontogenic differentiation-related markers were measured by quantitative real-time PCR (qRT-PCR) and western blot (WB). Immunofluorescence staining was used to measure mitophagy. Mitophagy-related proteins were analyzed by WB, and the levels of inflammation factors were examined using qRT-PCR, ELISA and immunohistochemistry. Alkaline phosphatase activity and alizarin red S intensity were evaluated to assess osteogenic differentiation. Acute pulp (AP) injury rat model was constructed to study the role of oe-GDF11 in vivo. RESULTS: GDF11 was downregulated in LPS-induced DPSCs, and LPS suppressed osteogenic/odontogenic differentiation and mitophagy. GDF11 overexpression promoted osteogenic/odontogenic differentiation in DPSCs through the activation of mitophagy. Furthermore, GDF11 upregulated SIRT3 to enhance FOXO3 expression by inhibiting its acetylation. GDF11 ameliorated LPS-induced inflammation and promoted osteogenic/odontogenic differentiation in DPSCs via enhancing SIRT3/FOXO3-mediated mitophagy. Besides, GDF11 overexpression suppressed inflammation and promoted dentin repair in AP rat models. CONCLUSION: GDF11 promoted SIRT3/FOXO3-mediated mitophagy to accelerate osteogenic/odontogenic differentiation in DPSCs, providing a novel target for pulpitis treatment.

[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.

[Biomechanical effect of 2 anchorages on maxillary protraction with cleft lip and palate: a finite element analysis].

PURPOSE: To establish cranio-maxillary complex finite element models (FEMs) in cleft lip and palate (CLP) patients with miniplate and tooth-borne anchorage, and to investigate the biomechanical effects on maxillary protraction. METHODS: The protracting process was simulated on FEMs established from a male patient's cone beam CT (CBCT) data to analyze the displacement and stress from different appliances. RESULTS: Four FEMs of unilateral cleft lip and palate (UCLP) or bilateral cleft lip and palate (BCLP) patients' cranio-maxillary complex with MA and TA were established. The maxillary arch on both sides of the cleft moved towards the cleft side during protraction, which was more obvious in the miniplate anchorage three-dimensional finite element models(FEM-MA) than the tooth-borne anchorage three-dimensional finite element models (FEM-TA).The amount of forward, downward displacement of the inferior orbital rim, paranasal area and middle maxilla point in the FEM-MA was larger than that in the FEM-TA, while the amount of forward displacement of premaxilla and upper canine in the FEM-TA was larger than that in the FEM-MA. The FEM-MA exhibited an orthopedic effect with more favorable stress distribution on the middle maxilla point while the FEM-TA showed a dentoalveolar effect with prominent stress distribution on the upper canine point. In addition, the FEM-MA showed a larger stress distribution area and sutural stress value than did the FEM-TA. The UCLP models showed an asymmetric pattern in stress distribution and displacement, which was larger on the cleft side than that on the non-cleft side. The amount of displacement of premaxilla in the BCLP models was smaller than that in the UCLP models. CONCLUSIONS: The established models have high geomagic and biomechanical similarities. It would be more advantageous to obtain more aesthetic outcomes and better stability using the miniplate anchorage.