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Granite rocks are currently one of the foremost raw materials that can be used for various economic purposes such as ornamentation and building materials, because they do not possess radioactive concentrations and have good physical and mechanical properties. The granite rocks of north Um Taghir are connected to neoproterozoic rocks and integrated to the north Arabian-Nubian Shield (ANS), which lies in Northeast Africa. Inductively coupled plasma mass spectrometry (ICP-MS) and X-ray fluorescence analysis, concurrent to some statistical analysis, have been carried for major oxides and some trace elements to extract much fundamental information by following certain mathematical methods. The exposed granite rock units in north Um Taghir are classified into four rock units represented by tonalite, granodiorite, monzogranite, and alkali-feldspar granite which are cut by different types of dikes. The magma of tonalite and granodiorite is low-to-medium K calc-alkaline affinity, while the magma of monzogranite and alkali-feldspar granite is medium-to-high K calc-alkaline affinity, and of metaluminous to peraluminous nature. Granite rocks show a slightly depletion of fractionated patterns from light rare earth elements (LREEs) to heavy rare earth elements (HREEs) with slightly positive to negative Eu anomalies from tonalite to monzogranite and alkali-feldspar granites. The statistical criteria have been achieved to explore the significant differences of radiological hazard parameters among samples. It is obvious that there is no homogeneity among samples; furthermore, in Kruskal–Wallis test, Mann–Whitney test, and Pearson correlation coefficient, it can be noticed that there are significant differences between each pair of samples: tonalite, monzogranite; tonalite, alkali-feldspar granite; granodiorite, monzogranite; and granodiorite, alkali-feldspar granite. There is a strong direct relationship among granodiorite and both tonalite and alkali-feldspar granite, and among alkali-feldspar granite and tonalite and granodiorite. There is a strong inverse relationship among monzogranite and tonalite, granodiorite, and alkali-feldspar granite. As stated by all results, it can be mentioned that the granite rocks have a worthy result of mechanical and physical properties. So that they can be used for various economic purposes.

Compositions of large nuclear cores (e.g. boiling water reactors) are highly heterogeneous in terms of fuel composition, control rod insertions and flow regimes. For this reason, they usually lack high order of symmetry (e.g. 1/4, 1/8) making it difficult to estimate their neutronic parameters for large spaces of possible loading patterns. A detailed hyperparameter optimization technique (a combination of manual and Gaussian process search) is used to train and optimize deep neural networks for the prediction of three neutronic parameters for the Ringhals-1 BWR unit: power peaking factors (PPF), control rod bank level, and cycle length. Simulation data is generated based on half-symmetry using PARCS core simulator by shuffling a total of 196 assemblies. The results demonstrate a promising performance by the deep networks as acceptable mean absolute error values are found for the global maximum PPF (~0.2) and for the radially and axially averaged PPF (~0.05). The mean difference between targets and predictions for the control rod level is about 5% insertion depth. Lastly, cycle length labels are predicted with 82% accuracy. The results also demonstrate that 10,000 samples are adequate to capture about 80% of the high-dimensional space, with minor improvements found for larger number of samples. The promising findings of this work prove the ability of deep neural networks to resolve high dimensionality issues of large cores in the nuclear area.

Introduction: The purpose of this study was to evaluate the validity of the cervical vertebral maturation (CVM) method as an indicator of skeletal age in the circumpubertal period by correlating it to the hand-wrist method (HWM). Methods: Hand-wrist and lateral cephalometric radiographs of 400 Chinese subjects were randomly selected. Their ages were 10 to 15 years for girls and 12 to 17 years for boys, so they were within the circumpubertal period. Skeletal ages were assessed according to the CVM method and the HWM. Results: The CVM was significantly correlated with HWM skeletal age (Spearman r = 0.9521 [boys] and 0.9408 [girls]). All patients in cervical vertebral stage 3 of the CVM corresponded to stages MP3-FG or MP3-G (around the peak of the growth spurt) in the HWM. Conclusions: The CVM is a valid indicator of skeletal growth during the circumpubertal period, providing information for timing of growth modification. [ABSTRACT FROM AUTHOR]

This study reports a novel identical complex disease allele harboring two non-synonymous mutations that were identified in two southern Chinese individuals of the same family with cleidocranial dysplasia (CCD). Blood samples were obtained from the proband, his parents, plus 100 matched control subjects. Exons 0 to 7 of the RUNX2 gene were amplified using specific primers and sequenced. Multiple sequence alignment and protein structure modeling was performed using ClustalW2 and MODBASE software while PolyPhen-2 and MutationTaster applications were employed to predict the disease-causing potential of the identified mutations. A complex disease allele in two affected individuals harboring two non-synonymous mutations in a cis-position on exons 4 (D273N) and 5 (P299L) were identified. The identified mutations were in the conserved region and changed the protein structure., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: In this study, we performed a case-control association analysis to determine whether the candidate genes COL2A1 and IGF-1 are susceptibility genes for mandibular prognathism (MP)., Methods: Eleven and five single-nucleotide polymorphisms (SNPs) located in COL2A1 and IGF-1, respectively, were selected and genotyped in 211 cases and 224 controls. The individual SNPs and the relevant haplotypes were analyzed and tested for an association with MP, to identify genes potentially associated with MP., Results: In the analysis of individual SNPs, the SNP rs1793953 in the COL2A1 gene showed a possible association with MP with regard to allelic frequency and genotypic distribution (p = 0.031; p = 0.025, respectively) in the 211 cases and 224 controls. The A allele of rs1793953 was associated with a significantly decreased risk of MP (OR: 0.74; 95% CI: 0.58-0.97). Linkage disequilibrium and haplotype analysis revealed that MP was not associated with haplotypes that included the rs1793953 alleles. IGF-1 gene did not show the association with MP., Conclusion: An association between polymorphism in the COL2A1 gene and MP was observed. The results suggested that the COL2A1 gene could be a new susceptibility gene for use in the study of genetic risk factors for MP., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Laser technique now is widely applied in orthodontic treatment and proved to have many benefits. Soft tissue lasers can be used to perform gingivectomy, frenectomy and surgical exposure of tooth with less bleeding and swelling, improved precision, reduced pain and less wound contraction. Other laser applications include enamel etching and bonding and bracket debonding. Lower level lasers have the potential effects of pain control and accelerating tooth movement. Clinicians must be aware of the safety issues and risks associated with laser and receive proper training before the laser treatment is started.

The aim of this study was to assess the effect of the flavonoid naringin on the growth of the spheno-occipital synchondrosis by quantifying the levels of expression of Sox9 and PTHrP in an in vitro mouse model. Fifty 1-day-old BALB/c mice were randomly assigned to experimental or control groups, and each group equally divided into five time frames (6, 24, 48, 72 and 168 hours). The mice were sacrificed with phenobarbitone sodium, and the spheno-occipital synchondroses dissected and cultured in control or experimental medium, with the experimental medium supplemented with 0.1 µm naringin. Sections of the specimens underwent immunohistochemical staining for Sox9 and PTHrP, and the amount of expression was quantified using true-colour RGB (red-green-blue) computer-assisted image-analysing system with digital imaging. Data analysis showed there was a significant increase of expression of Sox9 at 6 and 24 hours (P < 0.001) between experimental and control groups, however, there was no significant difference between the levels of expression of PTHrP between experimental and control groups at any of the time frames. There was a very weak correlation found in this study between the expression of PTHrP and Sox9. In conclusion, naringin enhances the growth of the spheno-occipital synchondrosis through over expression of Sox9. This is a successful in vitro model to study factors regulating the growth of the spheno-occipital synchondrosis.

Background: Supernumerary teeth are teeth, or tooth-like structures that have either erupted or remain unerupted in addition to the 20 primary and 32 permanent teeth., Aims: This paper attempts to (a) provide an overview of the proposed hypotheses and the current understanding of the aetiology of supernumerary teeth, and (b) review the published cases of supernumerary teeth occurring in families., Review: No studies have been able to distinguish between different aetiologies for the different locations of supernumerary teeth, while, from a developmental or molecular perspective, the proposed hypotheses may be plausible and explains the origin of different types of supernumerary teeth., Conclusion: The only clearly evident feature, based on the existing published reports, is that it is logical to state that supernumerary teeth have a genetic component in their aetiology.

Objectives: The objectives of this paper are to determine the storage stability of saliva at 37 °C over an 18-month period, and its influence on the DNA yield, purity, PCR protocols and genotyping efficacy., Materials and Methods: Of the 60 participants, blood samples were obtained from 10 and saliva from 50. Samples were subjected to different storage conditions: DNA extracted immediately; DNA extracted following storage at 37 °C for 1, 6, 12 and 18 months. Subsequently, DNA yield, OD(260/280) and OD(260/230) ratios were measured. The isolated DNA was used to amplify exons 0-7 of the RUNX2 gene and subsequently sequenced. Furthermore, 25 SNPs were genotyped., Results: The mean DNA yield, OD(260/280) and OD(260/230) ratios obtained from blood were 67.4 ng/μl, 1.8 ± 0.05 and 1.8 ± 0.4 respectively. DNA yield obtained from saliva was significantly higher than blood (p < 0.0001), ranging from 97.4 to 125.8 ng/μl while the OD(260/280) ratio ranged from 1.8 ± 0.13 to 1.9 ± 0.1. The success rates for the 25 SNPs ranged from 98 to 100 % for blood and 96-99 % for saliva samples with the genotype frequencies in Hardy-Weinberg equilibrium (>0.01)., Conclusions: Saliva can be stored at 37 °C for 18 months without compromising its quality and ability to endure genetic analyses., Clinical Relevance: Saliva is a viable source of human DNA to facilitate the feasibility of large-scale genetic studies.

Background Aims: The aim of this study was to engineer sizable three-dimensional cartilage-like constructs using stem cells isolated from human dental pulp stem cells (DPSCs)., Methods: Human DPSCs were isolated from teeth extracted for orthodontic treatment and enriched further using immuno-magnetic bead selection for stem cell marker CD146. Chondrogenic lineage differentiation of DPSCs induced using recombinant transforming growth factor β3 (TGFβ3) was verified by pellet culture. Because the use of recombinant proteins is associated with rapid degradation and difficult in vivo administration, we constructed the recombinant adeno-associated viral vector encoding human TGFβ3 and determined the best multiplicity of infection for DPSCs. Transduced DPSCs were seeded on poly-l-lactic acid/polyethylene glycol (PLLA/PEG) electrospun fiber scaffolds demonstrating proper attachment, proliferation and viability as shown by scanning electron microscopy micrographs and CCK-8 cell counting kit. Scaffolds seeded with DPSCs were implanted in the back of nude mice., Results: Transduced DPSCs highly expressed human TGFβ3 for up to 48 days and expressed chondrogenic markers collagen IIa1, Sox9 and aggrecan, as verified by immunohistochemistry and messenger RNA (mRNA). Immunohistochemistry for TGFβ3/DPSC constructs (n = 5/group) showed cartilage-like matrix formation with glycosaminoglycans. In vivo constructs with TGFβ3/DPSCs showed higher collagen type II and Sox9 mRNA expression relative to non-transduced DPSC constructs (n = 5/group). Western blot analysis confirmed this expression pattern on the protein level (n = 3/group)., Conclusions: Immuno-selected DPSCs can be successfully differentiated toward chondrogenic lineage, while expressing the chondrogenic inducing factor. Seeded on PLLA/PEG electrospun scaffold, human DPSCs formed three-dimensional cartilage constructs that could prove useful in future treatment of cartilage defects., (Copyright © 2013 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Objective: This study sought to perform mutational analysis of the RUNX2 gene in an 8-year-old girl with a diagnosis of cleidocranial dysplasia (CCD) without supernumerary teeth (proband) and her parents, plus in age and gender matched control subjects., Methods: Ethical approval and informed consent was obtained for this study. Blood samples were obtained and the isolated DNA was used to amplify exons 0-7 of the RUNX2 gene using specific primers, which was subsequently sequenced., Results: No mutations were identified in the coding regions of the RUNX2 gene., Conclusion: The absence of supernumerary teeth in this individual with CCD demonstrates that there are variations in the phenotypes and mere absence of mutations does not imply that CCD phenotype is not governed by RUNX2 gene as only two-thirds of the individuals exhibiting a CCD phenotype would reveal a RUNX2 mutation; therefore, the influence of copy number variations including large insertions, intragenic deletions, duplications, and inversions of genes cannot be excluded completely., (© 2012 Wiley Publishing Asia Pty Ltd.)

Purpose: The purposes of this study were to: (1) identify, within the literature, reports on the prevalence of supernumerary teeth that have used panoramic radiographs (PRs) as a diagnostic tool; and (2) reanalyze the prevalence data based on the current sensitivity figures for PRs in identifying supernumerary teeth., Methods: A comprehensive literature search in three databases identified 16 potential studies, of which seven were included in the final analysis. Based on the recent sensitivity data for PRs in identifying supernumerary teeth, the equation "P=r/q" was derived to reanalyze the prevalence data. Multiple regression analysis and paired t test were employed for the statistical analysis., Results: The prevalence figure ranged from 1.2 percent to three percent, and, subsequent to the application of the adjustment factor, it increased to range from 2.4 percent to six percent. The prevalence figures for males was significantly higher than for females (RR=1.37). Furthermore, due to insufficient studies, statistical analysis was unable to elicit ethnical differences in the prevalence figures., Conclusions: The prevalence of supernumerary teeth is higher than indicated in the published reports and ranges from 2.4 percent to six percent or possibly even higher.

Introduction: Functional appliances lead, in different degrees, to loss of anchorage in the lower arch. By anchoring them to the mandibular bone, any dental side effects may be avoided and the skeletal effect enhanced. Stability of bone-borne fixation would be affected by forces created by the pull of the masticatory muscles. We aimed to identify mean maximum forces produced by mandibular retrusive muscles, at different degrees of advancement., Subjects and Methods: Eighteen healthy adult volunteers participated in the study. Maximum retrusive force was measured using a splint/load cell system. Readings of the maximum forces of retrusion were taken from five mandibular positions: unstrained retruded position, and 4, 5, 6, and 7 mm anterior to the unstrained position. Data were presented as means ± SD and anova was performed to examine statistical significant differences between means of the maximum retrusion force., Results: Mean maximum retrusion force ranged between 63.3 and 198.2 newtons at the unstrained and 7 mm positions, respectively. It increased as the distance of advancement increased, being statistically significantly (p < 0.05) less at unstrained position compared with all advancement distances, 4 mm of advancement than 6 and 7 mm advancement, 5 mm of advancement than at 7 mm advancement., Conclusion: Magnitude of the forces exerted by muscles during voluntary maximum retrusion movement from different advancement positions increased proportionately as the retrusion distance increased up to 7 mm. Such range of high forces might be important to consider when designing a bone-borne functional appliance., (© 2012 John Wiley & Sons A/S.)

Objective: To evaluate the effectiveness of diode laser gingivectomy as an adjunct to nonsurgical periodontal treatment in the management of periodontal health among patients receiving fixed orthodontic appliance therapy (FOAT)., Materials and Methods: Thirty patients undergoing FOAT with gingival enlargement were block randomized into two treatment groups. The test group received diode laser gingivectomy (940-nm diode laser, ezlase, Biolase Technology Inc) as an adjunct to nonsurgical periodontal treatment. The control group received nonsurgical periodontal treatment only. For both groups, five periodontal parameters were assessed at baseline, 1 month, 3 months, and 6 months: Plaque Index, Gingival Index, bleeding on probing, probing pocket depth, and Gingival Overgrowth Index. Intra- and intergroup variations in the periodontal parameters were determined over time., Results: Both groups showed statistically significant improvements in periodontal health over the study period (P < .05). However, significant improvements in periodontal health were evident earlier among the test group subjects (P < .05). The magnitude of improvement in periodontal health compared to baseline was greater in the test group than in the control group for Gingival Overgrowth Index at 1 month (P < .001) and 3 months (P < .05), Gingival Index at 3 months (P < .05) and 6 months (P < .05), and probing pocket depth at 1 month (P < .05)., Conclusions: Nonsurgical periodontal management with or without the adjunct use of lasers can be effective in the management of gingival health problems among patients receiving FOAT. The adjunctive use of lasers can produce an earlier and greater improvement in gingival health.

Objective: The aim of this study was to evaluate the effect of unilateral and bilateral loss of posterior occlusal support on the expression of type II collagen, interleukin-1β and VEGF in the condylar cartilage of growing rats., Design: Thirty female Wistar rats (5 weeks old) were randomized into three groups: control, unilateral extraction of mandibular molar teeth, bilateral extraction of mandibular molar teeth. Animals were sacrificed 8 weeks after tooth extraction and the temporomandibular joints were prepared for immunohistochemical analysis., Results: Bilateral molar extraction increased the expression of interleukin-1β (P<0.01) and VEGF (P<0.01), while unilateral extraction increased the expression of interleukin-1β (P<0.05) and type II collagen (P<0.01). The expression of VEGF was higher on the extracted than on the non-extracted side (P<0.01) after unilateral extraction., Conclusion: Loss of posterior occlusal support alters the expression of type II collagen, interleukin-1β and VEGF in the condylar cartilage of rats. The expression pattern of these proteins is different when loss of occlusal support was bilateral or unilateral, including differences between extracted and non-extracted sides., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Objectives: This study sought to (i) determine the variations in prevalence figures based on the diagnostic tools employed, and (ii) provide an insight into the prevalence of supernumerary teeth., Methods: A comprehensive literature search of the prevalence reports on supernumerary teeth was conducted using two databases. Two independent observers rated these articles according to exclusion and inclusion criteria. 28 papers were included in the analysis to determine the variations in the prevalence figures in relation to the method of diagnosis, and 14 studies were included to estimate the prevalence figures for supernumerary teeth. Statistical analysis was computed using analysis of variance (ANOVA), Student Neumann-Keuls (SNK) test and multiple regression analysis., Results: Statistically significant differences were evident in the prevalence figures based only on a clinical examination compared with groups that also employed radiographs (p < 0.05, ANOVA, SNK). The prevalence figures for supernumerary teeth ranged from 0% to 3%. The mean prevalence value for the European white population [1.6% (±0.6)] was lower than that of the southern Chinese population [2.7% (±0.14)]. The overall prevalence of supernumerary teeth for males was significantly higher than for females [relative risk = 1.37 (1.13-1.50)]., Conclusions: Clinical examination plus some types of radiograph(s) are essential for determining the prevalence of supernumerary teeth; nevertheless, it is still underestimated. Several disparities in the prevalence reports make the available data on supernumerary teeth questionable.

Osteogenesis and angiogenesis are two closely correlated processes during bone growth, development, remodelling and repair.Vascular endothelial growth factor (VEGF) is an essential mediator during the process of angiogenesis. Based on an extensive literature search, which was carried out using the PubMed database and the keywords of osteogenesis, VEGF, endochondral ossification and intramembranous ossification, this manuscript reviews the role of VEGF in ossification, with emphasis on its effect in endochondral and intramembranous ossification. Osteogenesis and angiogenesis are closely correlated processes. VEGF acts as an essential mediator during these processes. It not only functions in bone angiogenesis but also in various aspects of bone development.

Objectives: To examine the biological adaptation of cranial base synchondroses (CBS) when the maxilla was forward positioned by orthopedic force., Setting and Sample Population: The Department of Orthodontics at Shanghai Jiao Tong University. 50 Sprague-Dawley rats, 4 weeks of age, were divided into experimental (n=30) and control groups (n=20)., Material and Methods: An orthopedic appliance was fitted to the cranio-maxillary complex to advance the maxilla forward. The animals in the experimental group, together with the counterparts in the control group, were sacrificed at days 1, 3, 5, 7, and 14, respectively. The whole cranial base housing both the spheno-ethmoid (SES) and spheno-occipital synchondroses (SOS) was removed for tissue processing and immunotest of Sox9, Core-binding factor α 1 (Cbfa1), and vascular endothelial growth factor (VEGF), three carefully selected growth factors that are markers of chondrogenesis in different stages and its transition to endochondral ossification. Semiquantitative analysis was also conducted by using a computerizing imaging system., Results: The temporal tendency of the changes in the expressions of the three growth factors featured an increase from Day 3 and onwards for Cbfa1 and VEGF, and a following decline after Day 5 for Sox9. In both SES and SOS, the expressions of the three growth factors were significantly stronger in the experimental groups than that in groups (p<0.05)., Conclusions: Protractive orthopedic force imposed on the maxilla provokes an enhancement of chondrogenic process in CBS., (© 2012 John Wiley & Sons A/S.)

OBJECTIVES. To evaluate the reliability of panoramic radiographs (PRs) for identifying supernumerary teeth (ST) and to determine whether the level of dental training of the observer influenced the identification of ST. METHODS. Seventy-five PRs were randomly selected from the patient records and 18 examiners independently rated 25 radiographs each, for specific risk factors as well as for a measure of adequacy. Subsequently, the results were paired with those of the other examiners who assessed the same set of PRs. Descriptive statistics were computed using Fisher's exact test, and kappa statistics were used to assess the inter- and intra-observer reliability. RESULTS. Four hundred and fifty PRs were available for analysis. The overall sensitivity and specificity figures were 50% and 98.3%, whereas the positive and negative predictive values were 90.6% and 83.6%, respectively. The sensitivity figures for Junior House Dental Officers and Postgraduate Paediatric Dental Trainees were 39.2% and 60.8%, whereas the specificity figures were 99.4% and 95% with slight inter-examiner and moderate intra-examiner reliability. CONCLUSIONS. Panoramic radiographs are unreliable for identifying ST, and higher level of dental training is essential for identifying ST., (© 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.)

The gram-negative anaerobic bacteria A. actinomycetemcomitans (Aa) and P. gingivalis (Pg) are key components in the aetiology of periodontal disease, and associated hard-tissue destruction. Resveratrol is a phytoalexin, produced naturally by several plants when under attack by bacterial or fungal pathogens. It is found in many foods including mulberries, peanuts and the skin of labrusca and muscadine grapes. The objective of this study was to evaluate the effect of resveratrol on the in vitro growth of periodontal pathogens Aa and Pg. For comparison, resveratrol's effect on a variety of other oral microorganisms was also evaluated. Resveratrol demonstrates a poor solubility in water, thus different concentrations of resveratrol in the solvent dimethyl sulphoxide (DMSO) were added to calibrated suspensions of Aa and Pg. As a control, a parallel series of dilutions containing the vehicle DMSO alone was made to measure the effect of the solvent. Minimum inhibitory concentrations of the periodontal pathogens were calculated. All suspensions were incubated for 1, 3, 6 and 24 h in an anaerobic chamber at 37 °C. At each time interval, selected dilutions from each culture broth were plated on blood agar plates. Colonies appearing on blood agar plates were visually counted at 3 days for Aa, and at 5 days for Pg. The periodontal bacteria showed a significant decrease (p < 0.05) in viable counts after 1 h, whilst no colony forming units could be observed after 24 h. The results suggest that resveratrol possesses significant antimicrobial properties on periodontal pathogens in vitro., (Copyright © 2011 John Wiley & Sons, Ltd.)

Sufficient osteoinduction is essential for the success and effectiveness of bone grafting. It was previously found that Salvia Miltiorrhiza (SM), a commonly used Chinese herb increased osteogenesis in vivo. The aim of this study is to investigate the effects of SM on bone cells in vitro, in an attempt to get a better understanding on how SM can promote bone remodeling. MC3T3-E1, an osteoblastic cell line, was cultured with SM for different time intervals (24, 48, and 72 h), whereas the control group consisted of cells cultured without any intervention. The mRNA expression of alkaline phosphatase (ALP), osteocalcin (OCN), osteoprotegerin (OPG), and the receptor activator of nuclear factor kappa B ligand (RANKL) were examined by real-time polymerase chain reaction (qPCR). The expression of ALP showed an early increase at 24 h by 50% (p < 0.001) and at 48 h by 13% (p < 0.001). OCN was decreased by 22% at 24 h (p < 0.001) but increased by 50% and 88% at 48 and 72 h, respectively (p < 0.001). RANKL showed an early increase at the first two time points of 24 and 48 h by 45% (p < 0.001) and 36% (p < 0.01), respectively, while OPG was up-regulated at the latter two time points by 10% at 48 h (p < 0.01) and 68% at 72 h (p < 0.001). Thus, OPG/RANKL was down-regulated first, and then up-regulated. SM enhances bone remodeling by regulating the gene expression of ALP, OCN, OPG, and RANKL. It is a potential medicinal herb to be utilized in the application that requires stimulation in bone cell activities., (Copyright © 2011 Orthopaedic Research Society.)

Introduction: Our objective was to compare the oral impacts experienced by patients treated with labial or customized lingual fixed orthodontic appliances., Methods: This was an age- and sex-matched prospective longitudinal study of 60 adult patients treated with either labial or customized lingual fixed orthodontic appliances over a 3-month period. Ratings of oral impacts experienced and satisfaction were made on visual analog scales at 3 time points after appliance fixation. Variations in oral impacts and satisfaction over the trajectory of treatment were assessed. Area-under-the-curve analyses were conducted to assess variations in oral impacts and satisfaction between the groups., Results: All patients experienced oral impact disturbances, although these disturbances decreased over time (P < 0.001). Patients treated with customized lingual appliances reported more oral discomfort (P < 0.001), dietary changes (P < 0.001), swallowing difficulty (P < 0.001), speech disturbances (P < 0.001), and social problems (P < 0.001) than did those in the other group. There was no significant difference between the groups regarding ratings of oral self-care, mastication, and satisfaction level of treatment (P > 0.05)., Conclusions: The findings indicate that oral impacts are commonly experienced during both labial and customized lingual fixed orthodontic therapies. However, the oral impacts decreased over the observational period. Patients treated with customized lingual appliances experienced more oral impacts. Both groups had similar levels of treatment satisfaction., (Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.)

From the point of better biocompatibility and sustainability, biobased shape memory polymers (SMPs) are highly desired. We used 1,3-propanediol, sebacic acid, and itaconic acid, which have been industrially produced via fermentation or extraction with large quantities as the main raw materials for the synthesis of biobased poly(propylene sebacate). Diethylene glycol was used to tailor the flexibility of the polyester. The resulted polyesters were found to be promising SMPs with excellent shape recovery and fixity (near 100% and independent of thermomechanical cycles). The switching temperature and recovery speed of the SMPs are tunable by controlling the composition of the polyesters and their curing extent. The continuously changed switching temperature ranging from 12 to 54 °C was realized. Such temperature range is typical for biomedical applications in the human body. The molecular and crystalline structures were explored to correlate to the shape memory behavior. The combination of potential biocompatibility and biodegradability of the biobased SMPs makes them suitable for fabricating biomedical devices.

To compare the amount of new bone and bone cells produced by psoralen in collagen matrix to that produced by collagen matrix in vivo. Eighteen bone defects, 5 mm by 10 mm were created in the parietal bone of nine New Zealand White rabbits. Six defects were grafted with psoralen mixed with collagen matrix. Six defects were grafted with collagen matrix alone (negative control--collagen) and six were left empty (negative control--empty). Animals were killed on day 14 and the defects were dissected and prepared for histological assessment. Quantitative analysis of new bone formation and bone cells were made on 100 sections (50 sections for each group) using image analysis. A total of 454% more new bone was present in defects grafted with psoralen in collagen matrix than those grafted with collagen matrix. No bone was formed in the negative control--empty group. The amount of bone forming osteoblasts was also significantly greater in the psoralen group than the negative control--collagen group. Psoralen in collagen matrix has the effect of increasing new bone formation locally in vivo. Psoralen in collagen matrix can be developed as a bone graft material., (Copyright © 2010 Orthopaedic Research Society.)

Mechanical stress induces human periodontal ligament (PDL) cells to express an osteoblastic phenotype in vitro. Core binding factor a1 (CBFA1) is a key regulator of osteoblast differentiation. This study was designed to investigate the role of CBFA1 in alveolar bone remodelling, specifically the expression of CBFA1 messenger RNA (mRNA) in human PDL cells under mechanical stress and its up- and downstream relationships with other bone remodelling markers. Cultured human PDL cells were exposed to mechanical stress. The expressions of CBFA1 and alkaline phosphatase (ALP), osteopontin (OPN), osteoprotegrin (OPG), and receptor activator nuclear factor kappa B ligand (RANKL) were detected before and after RNA interference (RNAi) of CBFA1. The data were analysed using a t-test and one-way analysis of variance. After mechanical stress loading, CBFA1 mRNA expression was raised initially, followed by an increased expression of ALP and RANKL, decreased expression of OPG, and a change in OPN expression. After CBFA1 knock-down in human PDL cells by small hairpin (sh) RNA, the expression of ALP, OPN, OPG, and RANKL also changed. These findings suggest that in the present model system CBFA1 may play an important role in PDL-mediated bone remodelling in response to mechanical stimulation. Mechanical stress: CBFA1-ALP and OPG-PDL homeostasis may be one of the signal transduction pathways of human PDL cell differentiation under mechanical stress without exclusion of the involvement of other pathways.

Objective: The results of a genome-wide scan suggested that chromosome locus 1p36 might be linked to the etiology of mandibular prognathism (MP) amongst Asian ethnicities. In this study, we performed a two-stage case-control association study to determine whether one or more genes that confer susceptibility to MP are located within this genomic region., Design: In the first stage of the study, we examined 103 single nucleotide polymorphisms (SNPs) on 1p36 across an 8.6Mb critical region and within four candidate genes in 158 cases and 147 controls to identify genes associated with MP. In the second stage of the study, we examined an additional 23 SNPs within the erythrocyte membrane protein band 4.1 (EPB41) gene in 211 cases and 224 controls., Results: Four SNPs located in the EPB41 gene showed possible allelic and genotypic associations with MP (P<0.03 and P<0.05, respectively) in the first stage. In the analysis of single SNPs in the second stage, the allele of rs4654388 showed the strongest significant association with MP (P=0.008) and the rs4654388 G-allele was associated with a significantly increased risk of MP (OR: 1.78, 95% CI: 1.16-2.74). Haplotype analysis revealed that MP was associated significantly with haplotype GTTCAGGT (P(corrected)=0.031), which included the rs4654388 G-allele., Conclusions: An association between genetic polymorphisms in the EPB41 gene and MP has been observed. Although the polymorphisms which may contribute to MP have not been determined, the results of our study suggest that the EPB41 gene could confer susceptibility to MP., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Unlabelled: Osteogenesis and angiogenesis are closely correlated. Vascular endothelial growth factor (VEGF) is believed to play a critical role in skeletal development., Objective: To investigate whether VEGF has direct effects on bone cells activities and to better understand how VEGF promotes bone remodeling., Materials and Methods: MC3T3-E1 cell line was cultured with and without VEGF in vitro. The cells in both control and test groups were collected at different culture time points of 24, 48 and 72 h. Real-time polymerase chain reaction (qPCR) was carried out to quantify the mRNA expression of VEGF receptor (VEGFR2), alkaline phosphatase (ALP) and osteocalcin (OCN), osteoprotegerin (OPG) and receptor activator of nuclear factor kappa β ligand (RANKL)., Results: The expression of VEGFR2 significantly increased by 53% at 24 h and remained increased by 8% at 72 h compared to control (p < 0.05). ALP showed an early increase by 73% at 24 h (p < 0.001), but dropped by 14 and 41% at 48 and 72 h, respectively (p < 0.05). OCN was down-regulated by 41% at 24 h but then up-regulated by 149% at 72 h (p < 0.001). The expression of OPG significantly decreased by 7% at 24 h (p < 0.001) while dramatically increased by 133% at 72 h (p < 0.001). RANKL remained unchanged at all three time points (p > 0.05)., Conclusion: VEGF promotes bone remodeling by direct effects on osteoblastic cells via regulating gene expression of ALP, OCN, and OPG through VEGFR2 signaling pathway., (© 2010 John Wiley & Sons A/S.)

Aim: A mandible bone-borne Herbst appliance (MBBHA) would avoid the proclination of the lower incisors that occurs with any teeth-borne functional appliance. But mapping of the bone characteristics at potential fixation areas around the mental foramen has not been carried out so far. The aim of this computer tomographic (CT) study was to evaluate bone thickness at specific positions around the mental foramen., Material and Methods: CT scans of 60 randomly chosen adult Hong Kong Chinese subjects (mean age 28 ± 6.3 years) were used to measure the bi-cortical bone thickness in the mandible in the mental foramen area. The thickness of buccal and lingual cortical and cancellous bone was assessed at the following locations: 10 mm (A10 mm) and 5 mm (A5 mm) anterior, 10 mm (P10 mm) and 5 mm (P5 mm) posterior, and 5 mm (Inf5 mm) below the mental foramen., Results: The amount of buccal cortical bone thickness ranged between 1.89 mm, 10 mm anterior of the mental foramen, and 2.16 mm, 10 mm posterior to its location. At the A10 mm level, cortical thickness showed a marginal statistically significant difference between A5 and A10 mm. The total amount of bone thickness ranged from 10.19 to 12.06 mm., Conclusion: At the locations studied around the mental foramen, a mean bicortical bone thickness of 10-12 mm was measured. No large variation in the thickness was found between bicortical bone thicknesses in the measured locations around the mental foramen. Thorough evaluation on a case-by-case basis is advisable., (© 2010 John Wiley & Sons A/S.)

Fructus Psoraleae extract is used in China for the treatment of bone diseases. The objective of the study was to investigate the systemic effect of Fructus Psoraleae extract consumption on bone histomorphology. Sixteen 8-week-old male BALB/c mice were divided into control and experimental groups. In the control group, eight mice were fed daily with distilled water. In the experimental group, eight mice were fed daily with distilled water mixed with Fructus Psoraleae extract. The mice were kept for 5 weeks and then killed. Using micro-computed tomography, 20 micro-tomographic slices with a separation of 0.25 mm were acquired to cover the proximal end of the left tibia of each mouse. Quantitative morphometry of the bone structure was performed. The results showed that consumption of Fructus Psoraleae extract significantly increased the bone volume/tissue volume ratio by 11.8%. The bone trabeculae increased by 7.1% in thickness so that the bone density was increased. To conclude, Fructus Psoraleae extract taken orally increases bone density and alters bone histomorphology., (Copyright © 2010 John Wiley & Sons, Ltd.)

Summary: The aim of this study was to evaluate the effects of orthodontic treatment on systemic levels of the inflammatory markers, C-reactive protein (CRP), tumour necrosis factor-alpha (TNF-alpha), and interleukin-6 (IL-6). The study group comprised 11 girls and 6 boys (mean age 13.1 years) treated with fixed appliances and distalizing headgear. Venous blood samples were taken from the cubital vein of each subject before treatment (T0) and then at three further time points during treatment (T1-T3), 2 months apart. The sera from these blood samples were analysed using enzyme-linked immunosorbent assay (ELISA) assay technology for CRP, TNF-alpha, and IL-6 concentration levels. Data were compared between baseline and subsequent sequential time points using a Mann-Whitney test for non-normally distributed variables. The results showed that there was no significant elevation of any of the three inflammatory markers at any of the time points. This research provides evidence that conventional orthodontic treatment is not associated with a systemic immune response in the factors investigated.

Summary: The aim of this prospective longitudinal study was to compare pain experiences among Chinese adult patients treated with labial and lingual orthodontic appliances. Sixty patients, 30 with labial appliances (18 females and 12 males, mean age 20.33 years, SD +/- 4.205) and 30 with lingual appliances (22 females and 8 males, mean age 21.63 years, SD +/- 2.236), rated their overall pain experience on a 100 mm visual analogue scale (VAS) at three time points: 1 week (T(1)), 1 month (T(2)), and 3 months (T(3)) after bracket placement. In addition, on a separate 100 mm VAS, they rated their pain experience at the locations of the tongue, lips, cheeks, gums, face, and jaw at T(1), T(2), and T(3). Changes in pain VAS were conducted using Friedman analysis of variance, area under the curve (AUC) analysis and the data were compared using a t-test. There was no significant difference in global ratings of pain among those treated with labial or lingual appliances (P > 0.05). Among both groups, global ratings of pain decreased over the study period (P < 0.001). Patients treated with lingual appliances reported higher ratings of tongue pain (P < 0.001), while those treated with labial appliances reported higher ratings of lip (P < 0.001) and cheek (P < 0.001) pain. The findings indicate that patients treated with labial and lingual appliances rate similarly the level of overall pain they experience during treatment. Ratings of overall pain experienced decreased for both treatment groups with time. However, ratings of pain differed at various sites with respect to the type of orthodontic appliance. These findings have implications in informing patients' treatment decision-making processes regarding labial and lingual appliances and in the management of discomfort associated with different treatment modalities.

In this study, transparent poly(vinyl alcohol) (PVA) and PVA/halloysite nanotubes (HNTs) bionanocomposite films were prepared by solution casting and glutaraldehyde (GA) crosslinking. The surface topography and chemistry of the films were characterized by atomic force microscopy (AFM) and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, respectively. Blending with HNTs induced changes in nanotopography and surface chemistry of PVA films. The mechanical properties of PVA were enhanced by the incorporated HNTs. The stain-induced crystallization was confirmed by DSC after tensile test. MC3T3-E1 osteoblast-like and NIH 3T3 fibroblast cells were cultured on neat PVA and PVA/HNTs films to evaluate the effects of surface nanotopography and composition on cell behavior. The observations indicated that MC3T3-E1 cell behavior strongly responded to surface nanotopography. On nanotube-dominant surface, cells exhibited a significantly higher level of adhesion than on neat PVA film, whereas neat PVA showed higher degree of osteoblast proliferation compared with PVA/HNTs. In vitro fibroblasts response demonstrated that both neat PVA and PVA/HNTs nanocomposite films were biocompatible and PVA/HNTs films favored to fibroblasts attach and growth below 7.5 wt % of HNTs incorporated. In summary, these results provided insights into understanding of PVA and PVA/HNTs bionanocomposite films in potential applications in bone tissue engineering and drug delivery systems., ((c) 2009 Wiley Periodicals, Inc.)

The objective of the study is to compare the amount of new bone produced by Buguzhi (Psoralea corylifolia fruit) extract in collagen matrix to that produced and collagen matrix in vivo. Eighteen bone defects, 5 mm by 10 mm, were created in the parietal bone of 9 New Zealand white rabbits. Six defects were grafted with Buguzhi extract mixed with collagen matrix. Six defects were grafted with collagen matrix alone (positive control) and 6 were left empty (negative control). Animals were sacrificed on day 14 and the defects were dissected and prepared for histological assessment. Quantitative analysis of new bone formation and bone cells was made on 100 sections (50 sections for each group) using image analysis. A total of 275% more new bone was present in defects grafted with Buguzhi extract in collagen matrix than those grafted with collagen matrix. No bone was formed in the negative control group. The amount of bone cells was also significantly greater in the Buguzhi group than in the positive control group. To conclude, Buguzhi extract in collagen matrix has the effect of increasing new bone formation locally in vivo. Buguzhi extract in collagen matrix can be used as a bone graft material.

Actinobacillus actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) are bacteria strongly associated with early onset, progressive and refractory periodontal disease and associated alveolar bone loss. Quercetin is a flavonoid found in many foods including apples, onions and tea. The aim of this study was to evaluate the effect of quercetin on in vitro growth of periodontal pathogens Aa and Pg. For comparison, quercetin's effect on several oral microbes was also evaluated. Different concentrations of quercetin solution were added to calibrated suspensions of Aa and Pg. All suspensions were incubated for 1, 3, 6, and 24 h in an anaerobic chamber at 37 degrees C. At each time point, selected dilutions from each culture broth were plated on blood agar plates. Colonies appearing on blood agar plates were visually counted on 3 days for Aa and 5 days for Pg. Minimum inhibitory concentrations of both periodontal pathogens were also determined. Both periodontal bacteria showed a significant decrease (p < 0.05) in viable counts after 1 h. No colony forming units of Pg could be observed after 24 h. The results suggest that quercetin possesses significant antimicrobial properties on periodontal pathogens in vitro., ((c) 2009 John Wiley & Sons, Ltd.)

Fixed functional appliance is an effective way of treating skeletal Class II malocclusion in children and adolescents. The following case report documented a 13-year-old boy with 15 mm overjet treated by a phase I 12-month growth modification therapy using Herbst appliance with Hyrax palatal expander and high pull headgear in a stepwise mandibular advancement protocol followed by a phase II pre-adjusted edgewise appliance therapy. It is one of the cases submitted for the Membership of Orthodontics Examination of the Royal College of Surgeons of Edinburgh., (Copyright © 2010 Elsevier. Published by Elsevier B.V. All rights reserved.)

To present current views that are pertinent to the investigation of the genetic etiology of Class III malocclusion. Class III malocclusion is thought to be a polygenic disorder that results from an interaction between susceptibility genes and environmental factors. However, research on family pedigrees has indicated that Class III malocclusion might also be a monogenic dominant phenotype. Recent studies have reported that genes that encode specific growth factors or other signaling molecules are involved in condylar growth under mechanical strain. These genes, which include Indian hedgehog homolog (IHH), parathyroid-hormone like hormone (PTHLH), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF), and variations in their levels of expression play an important role in the etiology of Class III malocclusion. In addition, genome-wide scans have revealed chromosomal loci that are associated with Class III malocclusion. It is likely that chromosomal loci 1p36, 12q23, and 12q13 harbor genes that confer susceptibility to Class III malocclusion. In a case-control association study, we identified erythrocyte membrane protein band 4.1 (EPB41) to be a new positional candidate gene that might be involved in susceptibility to mandibular prognathism. Most of the earlier studies on the genetic etiology of Class III malocclusion have focused on the patterns of inheritance of this phenotype. Recent investigations have focused on understanding the genetic variables that affect Class III malocclusion and might provide new approaches to uncovering the genetic etiology of this phenotype.

Objective: to compare the amount of new bone produced by Bio-Oss((R)) Collagen to that produced by collagen matrix in vivo., Method: eighteen bone defects, 5mm by 10mm were created in the parietal bone of 9 New Zealand White rabbits. 6 defects were grafted with Bio-Oss((R)) Collagen. 6 defects were grafted with collagen matrix alone (positive control) and 6 were left empty (negative control). Animals were killed on day 14 and the defects were dissected and prepared for histological assessment. Quantitative analysis of new bone formation was made on 100 sections (50 sections for each group) using image analysis., Results: A total of 339% more new bone was present in defects grafted with Bio-Oss((R)) Collagen than those grafted with collagen matrix (positive control). No bone was formed in the negative control group., Conclusion: Bio-Oss((R)) Collagen has the effect of stimulating new bone formation locally compared with collagen matrix in vivo. Bio-Oss((R) )Collagen may be utilized as a bone graft material.

This case report describes a 13-year-old boy with alveolar bony defect resulted from surgical removal of impacted upper canine transposed in the anterior region. The boy had a normal occlusion with malposition of upper central and lateral incisors. The treatment objectives were to align teeth, close spaces by mesial movement of the buccal segments in the upper jaw to repair bone loss. Fixed appliance with palatal root torque was used for the mesial movements, levelling, and alignment of teeth.Orthodontic tooth movement consisted of a sequence of root movement in a direction to increase the thickness of the labial cortical plate of bone, could ensure healthier periodontium. A healthier periodontium prior to space closure ensured repair of alveolar bony defect after surgical intervention. Orthodontic tooth movement should be added to our armamentarium for the repair of alveolar bony defect.

Objective: To present a treatment protocol for improved stability with Herbst appliance treatment in Class II adult cases., Materials and Methods: Sixteen Class II adults were treated at the University of Hong Kong with two phase treatment. The treatment protocol which leads to good stability was presented., Results: The protocol leading to stable correction of overjet, molar relationship and enhanced forward positioning of the mandible involved 12 months Herbst appliance treatment with stepwise advancement followed by fixed appliance., Conclusions: The long term stability of Herbst appliance treatment is influenced by the treatment protocol employed. Based on the stability of the adult group in the present study, it is recommended to treat for 12 months in a step-wise manner for mandibular advancement with over correction., (Copyright © 2010. Published by Elsevier Srl.)

Recombinant DNA projects generally involve cell-based gene cloning. However, because template DNA is not always readily available, in vitro chemical synthesis of complete genes from DNA oligonucleotides is becoming the preferred method for cloning. This article describes a new, rapid procedure based on Taq polymerase for the precise assembly of DNA oligonucleotides to yield the complete human fibroblast growth factor 1 (FGF1) gene, which is 468 bp long and has a G+C content of 51.5%. The new method involved two steps: (1) the design of the DNA oligonucleotides to be assembled and (2) the assembly of multiple oligonucleotides by PCR to generate the whole FGF1 gene. The procedure lasted a total of only 2 days, compared with 2 weeks for the conventional procedure. This method of gene synthesis is expected to facilitate various kinds of complex genetic engineering projects that require rapid gene amplification, such as cell-free whole-DNA library construction, as well as the construction of new genes or genes that contain any mutation, restriction site, or DNA tag.

The amount of new bone produced by grafting genistin in collagen matrix was compared to the bone produced by collagen matrix alone. A total of 18 bone defects (5 mm by 10 mm) were created in the parietal bone of 9 New Zealand White rabbits. Six defects were grafted with genistin mixed with collagen matrix, while 6 were grafted with collagen matrix alone (positive control) and 6 were left empty (negative control). Animals were killed on day 14 and defects were prepared histologically. Quantitative analysis of new bone formation and bone cells was carried out on 100 sections (50 sections for each group) using image analysis. A total of 520 per cent more new bone was present in defects grafted with genistin in collagen matrix than in defects grafted with collagen matrix alone (p less than 0.0001), while no bone was formed in the negative control group. The amount of bone forming osteoblasts was also significantly greater in the genistin group than the positive control group. Therefore, genistin in collagen matrix can increase new bone formation locally in vivo.

Objectives: The aim of this study was to compare the effectiveness of using Ping On ointment and using petroleum jelly in the treatment of temporomandibular joint (TMJ) and masticatory muscle pain, in order to establish the true efficacy of Ping On ointment., Methods: In this randomized, double-blinded, placebo-controlled trial, 55 subjects with TMJ and/or masticatory pain (Group I patients according to the Research Diagnostic Criteria for Temporomandibular Disorder (RDC/TMD) received Ping On ointment for 4 weeks, or placebo for 4 weeks. Subjects were evaluated with standard measures of efficacy: pain intensity measured by visual analogue scale and maximal comfortable mandibular opening, at baseline and again after 4 weeks of treatment., Results: Ping On ointment significantly reduced the symptoms of painful TMJs and/or masticatory muscles. Maximal comfortable mandibular opening also improved in the Ping On ointment group compared with the placebo, but was not clinically significant., Conclusions: This preliminary study suggests that topical application of Ping On ointment may be considered for further investigation as a potential first-line treatment modality, before prescribing analgesics, for the management of TMDs. It is topically applied, safe, reversible, and effective in managing TMDs and masticatory muscle pain.

Background: Orthodontic management of an ectopically erupted canine requires substantial amount of bodily movement which is difficult to perform and often results in root resorption., Case Presentation: A 9 year old girl presented with Class I malocclusion with crowding and ectopically positioned upper left canine (23). Treatment involved extraction of all first premolars. The alignment of the upper left canine was achieved by the modified 2 by 1 appliance., Conclusion: The design of this modified 2 by 1 appliance allows individualized bodily tooth movement of canine, it provides light and continuous force for physiological orthodontic movement with minimal root resorption.