[Maxillary dental and palatal morphological characteristics in 62 children with impacted maxillary canine in mixed dentition].

PURPOSE: The aim of this study was to compare the difference of dental arch and palatal morphology between children with impacted maxillary canine and without impacted maxillary canine, to provide reference for early diagnosis and treatment of impacted maxillary canine. METHODS: Sixty-two children, 8-11 years of age (9.8±1.04 years), were divided into experimental group and control group, with 31 children in each group. Digital casts were obtained using 3D laser scanner from maxillary models. Dental arch width, length, basal bone width, palatal width, height, surface area and volume were measured. Paired t test was performed with SPSS 24.0 software package. RESULTS: Dental arch width and palatal width were significantly narrower in experimental group than in control group(P<0.05), but there was on significant difference in dental arch length, basal bone width and palatal height between the two groups(P>0.05).Additionally, palatal surface area and volume were significantly larger in control group than in experimental group(P<0.05). CONCLUSIONS: Children with impacted maxillary canine have smaller maxillary dental arch width, palatal width, palatal surface area and volume compared to control group. Dental arch width, palatal width, palatal surface area and volume should be taken into consideration when early identifying impacted maxillary canine.

Role of Special AT-Rich Sequence-Binding Protein 2 in the Osteogenesis of Human Dental Mesenchymal Stem Cells.

Dental mesenchymal stem cells (MSCs) are recognized as a critical factor in repair of defective craniofacial bone owing to the multiple differentiation potential, the ability to regenerate distinct tissues, and the advantage that they can be easily obtained by relatively noninvasive procedures. Special AT-rich sequence-binding protein 2 (SATB2) is a nuclear matrix protein, involved in chromatin remodeling and transcriptional regulation, and has been reported to be as a positive regulator of osteoblast differentiation, bone formation, and bone regeneration in MSCs. In this study, we systematically investigated the capability of SATB2 to promote the osteogenic differentiation of periodontal ligament stem cells (PDLSCs), dental pulp stem cells (DPSCs), and stem cells from human exfoliated deciduous teeth (SHED). RNA-seq analysis and quantitative real-time PCR (RT-PCR) revealed that genes regulating osteogenic differentiation were differentially expressed among three cell types and SATB2 was found to be expressed at a relatively high level. When the three cell types overexpressed SATB2 with AdSATB2 infection, alkaline phosphatase (ALP) staining, ALP activity, Alizarin Red S staining, and quantification tended to increase with an increasing infection rate. It showed opposite results after infection with AdsiSATB2. RNA-seq analysis indicated that the expression of downstream osteogenic genes was affected by AdSATB2 infection and quantitative RT-PCR confirmed that nine osteogenic genes (Spp1, Sema7a, Atf4, Ibsp, Col1a1, Sp7, Igfbp3, Dlx3, and Alpl) were upregulated, to various extents, following SATB2 overexpression. In addition, quantitative PCR results indicated that SATB2 affected the expression of MSC markers. These results suggested an important role of SATB2 in the osteogenesis of PDLSCs, DPSCs, and SHED. Further research is warranted to investigate SATB2-mediated regulation of osteogenic differentiation and to evaluate the therapeutic use of SATB2 for the regeneration of defective craniofacial bone tissue.

[Three-dimensional morphological analysis of the palate of mouth-breathing children in mixed dentition].

OBJECTIVE: To study the effects of mouth-breathing on maxillary arch development by comparing the palatal morphology of mouth- and nose-breathing children in mixed dentition. METHODS: Children in mixed dentition were enrolled and categorized into mouth-breathing (test group) and nose-breathing groups (control group) according to their breathing patterns. Children's plaster models were scanned with 3D laser scanner, and the 3D data were reconstructed and measured using Minics 15.0 and Geomagic 12.0 software. Measurement data (inter-molar width, palatal height, palatal volume, and palatal surface area) of the two groups were compared, and the correlation among the four measurement items was analyzed. RESULTS: The participants were 73 children (37 in test group and 36 in control group) with a mean age of (8.63±0.78) years old. The test group had significantly smaller inter-molar width, palatal volume, and palatal surface area but significantly higher palatal height than the control group (P<0.05). Inter-molar width and palatal volume were positively correlated with the palatal surface area in the test group (P<0.05). Inter-molar width and palatal height were positively correlated with the palatal surface area in the control group (P<0.01). CONCLUSIONS: Mouth-breathing children have significantly reduced inter-molar width, palatal volume, and surface, and substantially increased palatal height, leading to different developmental patterns of the palatal morphology.

Associations between the NOGGIN rs227731 polymorphism and NSCL/P risk may be associated with ethnicities: A meta-analysis.

BACKGROUND: The aim of this study was to evaluate the association between the noggin rs227731 polymorphism on chromosome 17q22 and risk of nonsyndromic cleft lip with or without palate (NSCL/P). METHODS: Three online databases were searched, including Embase, PubMed, and Chinese National Knowledge Infrastructure. The strength of the associations was evaluated by odds ratios (ORs) and 95% confidence intervals (CIs). We also made a subgroup analysis to explore sources of heterogeneity. RESULTS: Nine comparisons from seven studies were included in this meta-analysis. We used five genetic models and found that the noggin rs227731 polymorphism may increase NSCL/P risk in Caucasians: C versus A: OR = 1.43, 95% CI, 1.30-1.58; CC versus AA: OR = 2.00, 95% CI, 1.59-2.52; CA versus AA: OR = 1.50, 95% CI, 1.27-1.77; CC+CA versus AA: OR = 1.64, 95% CI, 1.40-1.92; CC versus CA+AA: OR = 1.56, 95% CI, 1.30-1.87. However, for the Chinese population, no significant association between the rs227731 polymorphism and NSCL/P risk was found: C vs. A: OR = 1.04, 95% CI, 0.81-1.33; CC vs. AA: OR = 1.01, 95% CI, 0.52-1.95; CA vs. AA: OR = 1.03, 95% CI, 0.75-1.40; CC+CA vs. AA: OR = 1.04, 95% CI, 0.76-1.43; CC vs. CA+AA: OR = 1.01, 95% CI, 0.56-1.81. CONCLUSION: Our meta-analysis suggested that the rs227731 polymorphism may increase NSCL/P risk in Caucasians and may have no significant association in the Chinese population. Effects of individual and environmental risk factors and of gene-environment interactions may play a different role in Caucasians than in the Chinese population. More relevant case-control studies are required to obtain more precise results. Birth Defects Research 109:445-451, 2017. © 2017 Wiley Periodicals, Inc.

Pro-Inflammatory Cytokine TNF-α Attenuates BMP9-Induced Osteo/ Odontoblastic Differentiation of the Stem Cells of Dental Apical Papilla (SCAPs).

BACKGROUND/AIMS: Periapical periodontitis is a common oral disease caused by bacterial invasion of the tooth pulp, which usually leads to local release of pro-inflammatory cytokines and osteolytic lesion. This study is intended to examine the effect of TNF-α on BMP9-induced osteogenic differentiation of the stem cells of dental apical papilla (SCAPs). METHODS: Rat model of periapical periodontitis was established. TNF-α expression was assessed. Osteogenic markers and ectopic bone formation in iSCAPs were analyzed upon BMP9 and TNF-α treatment. RESULTS: Periapical periodontitis was successfully established in rat immature permanent teeth with periapical lesions, in which TNF-α was shown to release during the inflammatory phase. BMP9-induced alkaline phosphatase activity, the expression of osteocalcin and osteopontin, and matrix mineralization in iSCAPs were inhibited by TNF-α in a dose-dependent fashion, although increased AdBMP9 partially overcame TNF-α inhibition. Furthermore, high concentration of TNF-α effectively inhibited BMP9-induced ectopic bone formation in vivo. CONCLUSION: TNF-α plays an important role in periapical bone defect during the inflammatory phase and inhibits BMP9-induced osteoblastic differentiation of iSCAPs, which can be partially reversed by high levels of BMP9. Therefore, BMP9 may be further explored as a potent osteogenic factor to improve osteo/odontogenic differentiation in tooth regeneration in chronic inflammation conditions.

Evaluation of miR-29c inhibits endotheliocyte migration and angiogenesis of human endothelial cells by suppressing the insulin like growth factor 1.

MicroRNAs, a class of 22-nucleotide non-coding RNAs, modulate gene expression by associating with the 3'-untranslated regions (3'- UTRs) of messenger RNAs (mRNAs). Although multiple miRNAs are known to be regulated during angiogenesis, their individual roles in blood vessel development are still not fully understood. Herein, we investigate the role of miR-29c in regulating cell cycle and angiogenic phenotype of endothelial cells. The results showed that IGF-1 is highly expressed and down-regulated by miR-29c in human umbilical vein endothelial cells (HUVEC). Consistent with this preliminary finding, introduction of exogenous miR-29c or miR-29c inhibitor alters cell cycle progression, proliferation and tube formation of HUVEC, respectively. Furthermore, by using luciferase reporter assay, we find that the expression of IGF-1, a suppressor transcription factor, is directly regulated by miR-29c through 3'-UTR. In addition, we show that the selective inhibition of PI3K/AKT pathway prior to miR-29c stimulation prevents the expression of angiogenesis suppressor miRNAs that are family and cluster specific. As a conclusion, we find that miR-29c plays a significant role in regulating cell cycle, proliferation and angiogenic properties of HUVECs. This function is likely mediated through IGF-1 proteins at the post-transcriptional level. As a novel molecular target, miR-29c may have a potential value in the treatment of angiogenesis-associated diseases, such as cardiovascular diseases and cancers.

Evaluation of miR-29c inhibits endotheliocyte migration and angiogenesis of human endothelial cells by suppressing the insulin like growth factor 1.

MicroRNAs, a class of 22-nucleotide non-coding RNAs, modulate gene expression by associating with the 3'-untranslated regions (3'-UTRs) of messenger RNAs (mRNAs). Although multiple miRNAs are known to be regulated during angiogenesis, their individual roles in blood vessel development are still not fully understood. Herein, we investigate the role of miR-29c in regulating cell cycle and angiogenic phenotype of endothelial cells. The results showed that IGF-1 is highly expressed and down-regulated by miR-29c in human umbilical vein endothelial cells (HUVEC). Consistent with this preliminary finding, introduction of exogenous miR-29c or miR-29c inhibitor alters cell cycle progression, proliferation and tube formation of HUVEC, respectively. Furthermore, by using luciferase reporter assay, we find that the expression of IGF-1, a suppressor transcription factor, is directly regulated by miR-29c through 3'-UTR. In addition, we show that the selective inhibition of PI3K/AKT pathway prior to miR-29c stimulation prevents the expression of angiogenesis suppressor miRNAs that are family and cluster specific. As a conclusion, we find that miR-29c plays a significant role in regulating cell cycle, proliferation and angiogenic properties of HUVECs. This function is likely mediated through IGF-1 proteins at the post-transcriptional level. As a novel molecular target, miR-29c may have a potential value in the treatment of angiogenesis-associated diseases, such as cardiovascular diseases and cancers.

[Oral health status of 4-17-year-old orphan children and adolescents of Chongqing].

OBJECTIVE: To examine the oral health status among the orphan children and adolescents of Chongqing and assist in planning of the oral health programs. METHODS: According to the third national oral health investigation of epidemiology, the dental caries, gingival bleeding and calculus was examined among 317 orphan living in Chongqing, by cluster sampling. The statistical software SPSS 17.0 was used for the data analysis. RESULTS: In primary and permanent teeth, the prevalence of dental caries and mean DMFT (dmft) were found to be 50.00%, 1.94 +/- 2.81 and 39.53%, 0.90 +/- 1.38. There were no significant difference between female and male (P>0.05). But there was significant difference of the prevalence of permanent tooth caries between the age group under 12 (include 12) and above 12 (P < 0.05). It was also found that 35.25% of the orphan children and adolescents had caries in the first permanent molar, and there was significant difference between female and male (P < 0.05). Neither of the caries teeth above was treated nor the healthy teeth were sealed. The prevalence rate of gingival bleeding was 78.22%, and the calculus rate was 67.66%. CONCLUSION: The oral status of the orphan is poor, and this community has experienced a low utilization of preventive or therapeutic oral health services. In the future work, orphans should be considered as a priority group when make plans for oral health care.

[Submerged majority of primary molars associated with permanent teeth deletion and cone-shaped lateral incisor: a case report].

The combination of submerged primary molars and permanent teeth deletion is rare. This article reported a case of several submerged primary molars, permanent teeth deletion and a cone-shaped maxillary lateral incisor and discussed based on relevant literatures.

[Evaluation of the clinical effect of fluoride varnish in preventing caries of primary teeth].

OBJECTIVE: To evaluate the clinical effect of fluoride varnish in preventing caries of primary teeth, and to compare the caries prevention effects of fluoride varnish with two different concentrations. METHODS: 150 children whose ages were three year-old were randomly chosen from one of nurseries of Chongqing, and were randomly divided into four groups with 37 children in 0.5% fluoride varnish group, 38 children in 0.1% fluoride varnish group, 39 children in 0.5% sodium fluoride group and 36 children in blank group. The groups included 71 'girls and 79 boys. Protective measure was applied every half an year and the research has lasted for two years. The research was designed by double-blinded methods, and was carried out with the dental caries standard suggested by World Health Organization. All the data were collected and the clinical effects of four groups were compared. RESULTS: The average caries index and caries surface index of 0.1% fluoride varnish group and those of control groups were significantly higher than that of 0.5% fluoride varnish group. There were no significant difference between the average caries index and caries surface index of 0.1% fluoride varnish group and those of control groups. CONCLUSION: 0.5% fluoride varnish was effective in preventing caries of primary teeth.

[Establishment of malodor model and its effects on identifying the halitosis-related bacteria].

OBJECTIVE: To establish a salivary sediment malodor system, and to evaluate the effect of several kinds of bacteria dedicated to the halitosis formation, hence to identify halitosis-correlated bacteria. METHODS: The proportion of the supernatant and sediment, gained from centrifugal whole saliva, was adjusted to establish a salivary sediment malodor system incubated in facultative aerobic environment under 37 degrees C for 7 hours. The halitosis indexes in both gaseous phase and liquid phase were checked by direct sniffing, and volatile sulphur compounds (VSCs) and pH were determined by halimeter and glass electrode respectively between hours to evaluate the malodor formation. The suspended fluid of suspicious halitosis-correlated bacteria and non-halitosis-correlated bacteria and water control were introduced into the salivary sediment system incubated for 1 hour. The five groups were incubated in facultative aerobic environment under 37 degrees C in the residual hours. The halitosis indexes, VSCs and pH changes were recorded between hours. RESULTS: The salivary sediment malodor system can simulate the metabolism of halitosis formation to produce halitosis. The odors of the suspicious halitosis-correlated bacteria introduced groups were higher than the non-halitosis-correlated bacteria and water control group. CONCLUSION: With its simple but fundamental manipulations, incubated whole saliva is a powerful model for study of the metabolism of the oral mixed microbial flora, malodor formation, and other oral diseases-related processes.