Curcumin regulates EZH2/Wnt/ß-Catenin pathway in the mandible and femur of ovariectomized osteoporosis rats.

Osteoporosis (OP) behaves in different manners in different parts of the skeleton. This study aims to investigate the effects of curcumin on bone mass of the mandibular and femur from ovariectomized OP rats and to validate whether enhancer of zeste homolog 2 (EZH2)/Wnt/ß-Catenin pathway is involved in this process. Curcumin was administered intragastrically into ovariectomized rats for 12 weeks. The bone parameters and the morphology of the trabecular bone of the left mandible and left femur were assessed by micro-computed tomography assay. Morphological changes of the left mandible and left femur were evaluated by hematoxylin and eosin staining. The mRNA levels of EZH2, ß-Catenin, and Runx2 in the right mandible and right femur were examined by quantitative real-time polymerase chain reaction. Immunohistochemistry was performed to assess EZH2 expression. Both the mandible and femur exhibited OP-like changes in ovariectomized rats, while the mandible bone resorption was less than the femur bone resorption. Curcumin intragastric administration improved bone microstructure and promoted bone formation in the mandible and femur. Curcumin inhibited EZH2 mRNA level and induced that of ß-Catenin and Runx2 in the mandible and femur. Collectively, curcumin exerts protective effects against OP, possibly by regulating the EZH2/Wnt/ß-Catenin pathway.

[Characteristics of mandible and mandibular dentition according to vertical facial skeletal features of adolescents].

OBJECTIVE: We aim to examine teenagers with varying vertical facial skeletal types with near-normal occlusion. We further aim to identify and study mandibular morphology and dentition characteristics to establish normal ranges and variations for future clinical reference. METHODS: According to the results of the case studies, 42 adolescents with near-normal occlusion were divided into three groups, namely, low- (7 cases), average- (23 cases) and high-angle (12 cases) groups. We used Invivo 5 software for Digital Imaging and Communications in Medicine (DICOM) data to calculate the cant of occlusal plane, axis corner of L6, ∠L1/MP, ∠L6/MP, Balkwill angle and Bonwill triangle of each group. RESULTS: Markedly, the finding shows that the cant of occlusal plane and axis corner of L6 in the low-angle group were smaller than those of the other two groups. In the average-angle group, ∠L1/MP was larger than that of the high-angle group. Lastly, in the high-angle group, ∠L6/MP was smaller than those of the two other groups. On the one hand, these differences were considered statistically significant (P<0.05). On the other hand, other measurements show that these differences were considered statistically non-significant (P>0.05). CONCLUSIONS: In the low-angle group, the parallelisation of the occlusal plane tends to be more obvious compared with the two other groups. In the coronal section of the low-angle group, the axis of the mandibular first molar is up-right, whereas it is distally tilted in the sagittal section of the high-angle group. Furthermore, a number of differences are noted in the adult groups. Factors, such as aging and development in the craniofacial region, lead to changes in functional occlusion.

[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.

[Three-dimensional finite element model of maxillary protraction of the maxilla in patients with cleft lip and palate].

OBJECTIVE: To determine the effective rule of protraction in different directions,strains, and shifts of maxillary bone,and to supply the scientific data for treatment of the maxilla in patients with cleft lip and palate. METHODS: " Based on the establishment of 3-dimensional finite element model of maxilla with cleft lip and palate,ANSYS 10.0 software was used to simulate protraction,and then we analyzed the change of maxillary stress and shift in the same force of traction in different directions. RESULTS: With 500 g per lateral protraction and the protraction angle from 20 degree to 45 degree,the maxillary shifted upward, forward, and outward, and the shape of maxillary plate bow showed internal shrinkage. There was a close relation between the internal shrinkage and the direction of protraction. The smaller the angle between the direction of protraction and the functional occlusion plane,the larger the internal shrinkage of tooth bow. The larger the angle between the direction of protraction and the functional occlusion plane,the smaller the internal shrinkage of tooth bow. CONCLUSION: With protraction,the maxilla grows upward, forward, and outward, and the maxillary palate shinks internally. There is a close relation between the direction of protraction and the range of internal shrinkage.

Establishment of 3-dimensional finite element model of maxillary in human complete unilateral cleft lip and palate with spiral CT scan.

OBJECTIVE: To explore a faster and more precise method to establish a 3-dimensional (3 D) finite element model of maxillary in human complete unilateral cleft lip and palate. METHODS: The surface of the model was created using Materialists Interactive Medical Image Control System (Mimics) software to deal with Dicom standard files obtained by scanning the cranium of the patient with multi-slice helical CT. The 3D finite element model for complete unilateral cleft lip and plate in maxillary was established by Ansys software. RESULTS: A 3D finite element model of maxillary in human complete unilateral cleft lip and palate was constructed with 27,405 units and 26,876 nodes. CONCLUSION: The combination of Mimics software, Geomagic studio software, Ansys software, and spiral CT is able to create a 3D finite element counter model, which provides a faster and more valid method to study complete unilateral cleft lip and palate.

[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.

[MBT straight wire for Class II division I malocclusion cases].

OBJECTIVE: To evaluate the therapeutic effects of MBT straight wire on extraction case of Class II division I. METHODS: Thirty-six class II division I malocclusion patients were treated with MBT straight wire by extracting 4 bicuspid premolars or 2 maxillary bicuspid premolars. The X-ray cephalograms were analyzed before and after the treatment of MBT straight wire. RESULTS: After the treatment, the overjet was reduced by 6.04 mm (P < 0.01); U1-NA was reduced by 15.43 degrees (P <0.01); and U1-NA (mm) was reduced by 4.71 mm (P <0.01). ANB was significantly reduced (P < 0.05). CONCLUSION: MBT straight wire not only shortens the operation but also shows superior effect for Class II division I malocclusion cases.

[Construction and validation of a three-dimensional finite element model of cranio-maxillary complex with sutures in unilateral cleft lip and palate patient].

PURPOSE: To explore an effective method to construct and validate a finite element model of the unilateral cleft lip and palate(UCLP) craniomaxillary complex with sutures, which could be applied in further three-dimensional finite element analysis (FEA). METHODS: One male patient aged 9 with left complete lip and palate cleft was selected and CT scan was taken at 0.75mm intervals on the skull. The CT data was saved in Dicom format, which was, afterwards, imported into Software Mimics 10.0 to generate a three-dimensional anatomic model. Then Software Geomagic Studio 12.0 was used to match, smoothen and transfer the anatomic model into a CAD model with NURBS patches. Then, 12 circum-maxillary sutures were integrated into the CAD model by Solidworks (2011 version). Finally meshing by E-feature Biomedical Modeler was done and a three-dimensional finite element model with sutures was obtained. A maxillary protraction force (500 g per side, 20° downward and forward from the occlusal plane) was applied. Displacement and stress distribution of some important craniofacial structures were measured and compared with the results of related researches in the literature. RESULTS: A three-dimensional finite element model of UCLP craniomaxillary complex with 12 sutures was established from the CT scan data. This simulation model consisted of 206 753 individual elements with 260 662 nodes, which was a more precise simulation and a better representation of human craniomaxillary complex than the formerly available FEA models. By comparison, this model was proved to be valid. CONCLUSIONS: It is an effective way to establish the three-dimensional finite element model of UCLP cranio-maxillary complex with sutures from CT images with the help of the following softwares: Mimics 10.0, Geomagic Studio 12.0, Solidworks and E-feature Biomedical Modeler.

[A preliminary study on the functional occlusion characters of the patients who had essential root resorption in anterior teeth].

PURPOSE: In order to determine the effect of functional occlusion on the essential root resorption, we compared the characters of functional occlusion between the patients who had essential root resorption in anterior teeth and who didn't have. METHODS: Panoramic radiography, periapical films and clinical data were used to diagnose the essential root resorption before the patients received orthodontic treatment. Fifteen patients who had 2-3 degree root resorption were divided into the experimental group, while 15 patients who didn't have were chosen as control group according to their age and sex. The functional occlusion of the cases in the experimental group and control group was checked on Denar Mark II articulator and via clinical examination, and the indexes of functional occlusion during protrusive and lateral movement in two groups were recorded. SPSS 13.0 software package was used for statistical analysis. RESULTS: The results showed that the number of anterior teeth occlusal interferences during lateral movement in the experimental group was more than that in control group by clinical (P<0.05) or articulator examination (P<0.05), but the number of posterior teeth occlusal interferences didn't have significant difference between the two groups. There was no significant difference in the retrusive range (RCP-ICP) in vertical, anterior-posterior and lateral direction respectively. CONCLUSION: It is suggested that as a kind of long-standing and minor trauma, the anterior teeth occlusal interferences during lateral movement might be a cause of essential root resorption in anterior teeth.

[An experimental study of the effects of root-canal treatment on orthodontic movement in cat cuspids].

PURPOSE: To evaluate the effectiveness of orthodontic forces in moving teeth after root canal therapy and the risk of apical resorption which may happen during orthodontic movement in an animal model. METHODS: Under general anesthesia, root canal therapy was performed on the mandibular canines on one side of 16 adult cats. Tipping movement of the canines was induced with an orthodontic spring (100 to 120 g). Eight weeks later, tooth movement was assessed from pre- and posttreatment mandibular casts, including measurement of root lengths in both radiographs and histological sections. All the data were analysed with SPSS 11.0 for windows. Student's t test was used for comparisons between paired groups. RESULTS: The results showed that teeth after root canal therapy and vital teeth moved similar distances when subjected to the same forces (P>0.05). And teeth after root canal therapy had greater loss of cementum after tooth movement than vital teeth (P<0.05), but without significant differences in radiographic root length (P>0.05). CONCLUSIONS: Teeth after root canal therapy can be moved orthodontically as readily as vital teeth when subjected to the same orthodontic forces under the conditions of the study. However, teeth after root canal therapy have more root resorption than vital teeth during orthodontic movement which may not be detected form the radiography.