Effect of bone morphogenetic protein-4 (BMP-4) on the expression of Sox2, Oct-4 and c-Myc in human periodontal ligament cells during long-term culture

Recent studies demonstrated endogenous expression level of Sox2, Oct-4 and c-Myc is correlated with the pluripotency and successful induction of induced pluripotent stem cells (iPSCs). Periondontal ligament cells (PDLCs)have multi-lineage diferentiation capability and ability to maintain undifferentiated stage, which makes PDLCs a suitable cell source for tissue repair and regeneration. To elucidate the effect of in vitro culture condition on the stemness potential of PDLCs, we explored the cell growth, proliferation, cell cycle, and the expression of Sox2, Oct-4 and c-Myc in PDLCs from passage 1 to 7 with or without the addition of recombinant human BMP4(rhBMP4). Our results revealed that BMP-4 promoted cell growth and proliferation, arrested PDLCs in S phase of cell cycle and upregulated PI value. It was revealed that without the addition of rhBMP4, the expression of Sox2, Oct-4 and c-Myc in PDLCs only maintained nucleus location until passage 3, then lost nucleus location subsequently. The mRNA expression in PDLCs further confirmed that the level of Sox2 and Oct-4 peaked at passage 3, then decreased afterwards, whereas c-Myc maintained consistently upregulation along passages. after the treatment with rhBMP4, the expression of Sox2, Oct-4 and c-Myc in PDLCs maintained nucleus location even at passage 7 and the mRNA expression of Sox2 and Oct-4 significantly upregulated at passage 5 and 7. These results demonstrated that addition of rhBMP-4 in the culture media could improve the current culture condition for PDLCs to maintain in an undifferentiated stage.

Framing Movements for Gesture Interface Design

Gesture interfaces are an attractive avenue for human-computer interaction, given the range of expression that people are able to engage when gesturing. Consequently, there is a long running stream of research into gesture as a means of interaction in the field of human-computer interaction. However, most of this research has focussed on the technical challenges of detecting and responding to people’s movements, or on exploring the interaction possibilities opened up by technical developments. There has been relatively little research on how to actually design gesture interfaces, or on the kinds of understandings of gesture that might be most useful to gesture interface designers. Running parallel to research in gesture interfaces, there is a body of research into human gesture, which would seem a useful source to draw knowledge that could inform gesture interface design. However, there is a gap between the ways that ‘gesture’ is conceived of in gesture interface research compared to gesture research. In this dissertation, I explore this gap and reflect on the appropriateness of existing research into human gesturing for the needs of gesture interface design. Through a participatory design process, I designed, prototyped and evaluated a gesture interface for the work of the dental examination. Against this grounding experience, I undertook an analysis of the work of the dental examination with particular focus on the roles that gestures play in the work to compare and discuss existing gesture research. I take the work of the gesture researcher McNeill as a point of focus, because he is widely cited within gesture interface research literature. I show that although McNeill’s research into human gesture can be applied to some important aspects of the gestures of dentistry, there remain range of gestures that McNeill’s work does not deal with directly, yet which play an important role in the work and could usefully be responded to with gesture interface technologies. I discuss some other strands of gesture research, which are less widely cited within gesture interface research, but offer a broader conception of gesture that would be useful for gesture interface design. Ultimately, I argue that the gap in conceptions of gesture between gesture interface research and gesture research is an outcome of the different interests that each community brings to bear on the research. What gesture interface research requires is attention to the problems of designing gesture interfaces for authentic context of use and assessment of existing theory in light of this.

Effectiveness of cysteine proteases on protein/pigment film removal

Objective: Theaflavin (TF) from the black tea can react to human salivary proline-rich proteins (PRPs) to form stains on exposed dental surfaces. Here, we employed a model of protein/pigment film using TF and dephosphorylated bovine b-casein (Db-CN), which has an extended conformation, similar to that of salivary PRPs, on a sensor surface to assess the efficacy of cysteine proteases (CPs) including papain, stem bromelain, and ficin, on removing TF bound to Db-CN and the control TF readsorption on the residual substrate surfaces was also measured. Methods: The protein/pigment complex film was built by using a quartz crystal microbalance with dissipation (QCM-D). The efficacies of CPs were assessed by Boltzman equation model. The surface details were detected by grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles. Results: The efficacy order of CPs on hydrolyzing protein/pigment complex film is ficin > papain > bromelain. The results from grazing angle infrared spectroscopy spectra, atomic force microscopy images, and contact angles demonstrated that TF bound on the Db- CN was effectively removed by the CPs, and the amount of TF readsorption on both the residual film of the Db-CN/TF and the Db-CN was markedly decreased after hydrolysis. Conclusion: This study indicates the potential application of the CPs for tooth stain removal and suggests that these enzymes are worthy of further investigation for use in oral healthcare.

Randomized controlled trial : a randomized controlled clinical trial comparing a remineralizing paste with an antibacterial gel to prevent early childhood caries

PURPOSE: The purpose of this study was to compare twice daily tooth-brushing using 0.304 percent fluoride toothpaste alone with: (1) twice daily tooth-brushing plus once daily 10% casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) paste; and (2) twice daily tooth-brushing plus once daily 0.12% chlorhexidine gel (CHX) for reducing early childhood caries (ECC) and mutans streptococci (MS) colonization. METHODS: Subjects (n=622) recruited at birth were randomized to receive either CPP-ACP or CHX or no product (study control [SC]). All children were examined at 6, 12, and 18 months old in their homes, and at 24 months old in a community dental clinic. RESULTS: At 24 months old, the caries incidence was 1% (2/163) in CPP-ACP, 2% (4/180) in CHX, and 2% (3/188) in SC groups. In children who were previously MS colonized at 12 and 18 months old, 0% (0/11) and 5% (3/63), respectively, of the CPP-ACP group remained MS-positive versus 22% (2/9) and 72% (18/25) in CHX and 16% (4/25) and 50% (7/14) in SC groups (P<.001). CONCLUSIONS: There is insufficient evidence to justify the daily use of casein phosphopeptide-amorphous calcium phosphate or chlorhexidine gel to control early childhood caries.

A randomised, controlled clinical trial comparing chlorhexidine gel and low-dose fluoride toothpaste to prevent early childhood caries

Objectives This randomised, controlled trial compared the effectiveness of 0.12% chlorhexidine (CHX) gel and 304% fluoride toothpaste to prevent early childhood caries (ECC) in a birth cohort by 24 months. Methods The participants were randomised to receive either (i) twice daily toothbrushing with toothpaste and once daily 0.12% CHX gel (n = 110) or (ii) twice daily toothbrushing with toothpaste only (study controls) (n = 89). The primary outcome measured was caries incidence and the secondary outcome was percentage of children with mutans streptococci (MS). All mothers were contacted by telephone at 6, 12, and 18 months. At 24 months, all children were examined at a community dental clinic. Results At 24 months, the caries prevalence was 5% (3/61) in the CHX and 7% (4/58) in the controls (P = 0.7). There were no differences in percentages of MS-positive children between the CHX and control groups (54%vs 53%). Only 20% applied the CHX gel once daily and 80% less than once daily. Conclusions Toothbrushing using 304% fluoride toothpaste with or without the application of chlorhexidine gel (0.12%) reduces ECC from 23% found in the general community to 5–7%. The lack of effect with chlorhexidine is likely to be due to low compliance.

Cost-effectiveness of a telephone-delivered education programme to prevent early childhood caries in a disadvantaged area : a cohort study

Objectives Early childhood caries is a highly destructive dental disease which is compounded by the need for young children to be treated under general anaesthesia. In Australia, there are long waiting periods for treatment at public hospitals. In this paper, we examined the costs and patient outcomes of a prevention programme for early childhood caries to assess its value for government services. Design Cost-effectiveness analysis using a Markov model. Setting Public dental patients in a low socioeconomic, socially disadvantaged area in the State of Queensland, Australia. Participants Children aged 6 months to 6 years received either a telephone prevention programme or usual care. Primary and secondary outcome measures A mathematical model was used to assess caries incidence and public dental treatment costs for a cohort of children. Healthcare costs, treatment probabilities and caries incidence were modelled from 6 months to 6 years of age based on trial data from mothers and their children who received either a telephone prevention programme or usual care. Sensitivity analyses were used to assess the robustness of the findings to uncertainty in the model estimates. Results By age 6 years, the telephone intervention programme had prevented an estimated 43 carious teeth and saved £69 984 in healthcare costs per 100 children. The results were sensitive to the cost of general anaesthesia (cost-savings range £36 043–£97 298) and the incidence of caries in the prevention group (cost-savings range £59 496–£83 368) and usual care (cost-savings range £46 833–£93 328), but there were cost savings in all scenarios. Conclusions A telephone intervention that aims to prevent early childhood caries is likely to generate considerable and immediate patient benefits and cost savings to the public dental health service in disadvantaged communities.

Flapless dental implant surgery : a retrospective study of 1,241 consecutive implants

Purpose: The purpose of this study was to identify retrospectively the predictors of implant survival when the flapless protocol was used in two private dental practices. Materials and Methods: The collected data were initially computer searched to identify the patients; later, a hand search of patient records was carried out to identify all flapless implants consecutively inserted over the last 10 years. The demographic information gathered on statistical predictors included age, sex, periodontal and peri-implantitis status, smoking, details of implants inserted, implant locations, placement time after extraction, use of simultaneous guided hard and soft tissue regeneration procedures, loading protocols, type of prosthesis, and treatment outcomes (implant survival and complications). Excluded were any implants that required flaps or simultaneous guided hard and soft tissue regeneration procedures, and implants narrower than 3.25 mm. Results: A total of 1,241 implants had been placed in 472 patients. Life table analysis indicated cumulative 5-year and 10-year implant survival rates of 97.9% and 96.5%, respectively. Most of the failed implants occurred in the posterior maxilla (54%) in type 4 bone (74.0%), and 55.0% of failed implants had been placed in smokers. Conclusion: Flapless dental implant surgery can yield an implant survival rate comparable to that reported in other studies using traditional flap techniques.

RANKL expression in periodontal disease : where does RANKL come from?

Periodontitis is an inflammatory disease characterized by periodontal pocket formation and alveolar bone resorption. Periodontal bone resorption is induced by osteoclasts and receptor activator of nuclear factor-κB ligand (RANKL) which is an essential and central regulator of osteoclast development and osteoclast function. Therefore, RANKL plays a critical role in periodontal bone resorption. In this review, we have summarized the sources of RANKL in periodontal disease and explored which factors may regulate RANKL expression in this disease.

A randomized controlled trial of a 10 percent CPP-ACP cream to reduce mutans streptococci colonization

Purpose The purpose of this study was to investigate the effectiveness of a 10 percent casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) cream to reduce mutans streptococci (MS) colonization and prevent early childhood caries. Methods The cohort was randomized at mean age of 11 days old to receive once-daily CPP-ACP cream (n=102) or no product (comparison group; n=89) from the time of first tooth eruption. All mothers were contacted by telephone at six, 12, and 18 months and advised to brush their children's teeth twice daily with low-dose fluoride toothpaste. At 24 months, all children were examined at a community clinic. Results At 24 months old, one out of 65 (2 percent) children in the CPP-ACP group had caries vs. four out of 58 (seven percent) in the comparison group (difference not statistically significant). There were fewer MS-positive children in the CPP-ACP group (26 percent) vs. the comparison group (47 percent; P=.02). A dose-response effect of CPP-ACP usage on MS was observed, where MS was present in eight percent of regular CPP-ACP users, 28 percent of irregular users, and 47 percent of non-users (P<.02). Conclusions CPP-ACP reduced the percentages of mutans streptococci-positive 24-month-old children, although it did not reduce caries prevalence.

Associations between area-level disadvantage and DMFT among a birth cohort of Indigenous Australians

Background Individual-level factors influence DMFT, but little is known about the influence of community environment. This study examines associations between community-level influences and DMFT among a birth cohort of Indigenous Australians aged 16–20 years. Methods Data were collected as part of Wave 3 of the Aboriginal Birth Cohort study. Fifteen community areas were established and the sample comprised 442 individuals. The outcome variable was mean DMFT with explanatory variables including diet and community disadvantage (access to services, infrastructure and communications). Data were analysed using multilevel regression modelling. Results In a null model, 13.8% of the total variance in mean DMFT was between community areas, which increased to 14.3% after adjusting for sex, age and diet. Addition of the community disadvantage variable decreased the variance between areas by 4.8%, indicating that community disadvantage explained one-third of the area-level variance. Residents of under-resourced communities had significantly higher mean DMFT (β=3.86, 95% CI 0.02¬, 7.70) after adjusting for sex, age and diet. Conclusions Living in under-resourced communities was associated with greater DMFT among this disadvantaged population, indicating that policies aiming to reduce oral health-related inequalities among vulnerable groups may benefit from taking into account factors external to individual-level influences.

Root caries patterns and risk factors of middle-aged and elderly people in China

The objectives of this study were to describe root caries patterns of Chinese adults and to analyze the effect of selected demographic and socioeconomic factors on these patterns. A total sample of 1080 residents aged 35-44-years-old and 1080 residents aged 65-74-years-old from three urban and three rural survey sites in Hubei Province participated in both an oral health interview and a clinical oral health examination. Root surface caries prevalence rates were 13.1% in the middle-aged group and 43.9% in the elderly group. The mean number of teeth affected by caries in the middle-aged group was reported at 0.21 and 1.0 in the elderly group. Mean Root Caries Index (RCI) scores of the middle-aged were reported at 6.29 and elderly subjects were reported at 11.95. Elderly people living in rural areas reported a higher RCI score (13.24) than those living in urban areas (10.70). A significantly higher frequency of root surface caries was observed in elderly participants (P < 0.001, OR = 3.80) and ethnic minorities (P < 0.001, OR = 1.93). In addition, smokers, nontea drinkers, and those with an annual household income of 10,000 yuan or less tended to have higher caries prevalence. RCI figures for the different tooth types ranged from 1% to 16%, indicating a wide variation in attack rates. In conclusion, our study suggests that root surface caries occurrence is high among the Chinese adult population, especially older adults. With an increasing number of retained teeth in both middle-aged and elderly people, root caries is a growing disease in the People's Republic of China which deserves more attention in future research.

RF plasma sputtering deposition of hydroxyapatite bioceramics : synthesis, performance, and biocompatibility

Hydroxyapatite (HA) coatings have numerous applications in orthopedics and dentistry, owing to their excellent ability to promote stronger implant fixation and faster bone tissue ingrowth and remodeling. Thermal plasma spray and other plasma-assisted techniques have recently been used to synthesize various calcium phosphate-based bioceramics. Despite notable recent achievements in the desired stoichiometry, phase composition, mechanical, structural, and bio-compatible properties, it is rather difficult to combine all of the above features in a single coating. For example, many existing plasma-sprayed HA coatings fall short in meeting the requirements of grain size and crystallinity, and as such are subject to enhanced resorption in body fluid. On the other hand, relatively poor interfacial bonding and stability is an obstacle to the application of the HA coatings in high load bearing Ti6Al4V knee joint implants. Here, we report on an alternative: a plasma-assisted, concurrent, sputtering deposition technique for high performance biocompatible HA coatings on Ti6Al4V implant alloy. The plasma-assisted RF magnetron co-sputtering deposition method allows one to simultaneously achieve most of the desired attributes of the biomimetic material and overcome the aforementioned problems. This article details the film synthesis process specifications, extensive analytical characterization of the material's properties, mechanical testing, simulated body fluid assessments, biocompatibility and cytocompatibility of the HA-coated Ti6Al4V orthopedic alloy. The means of optimization of the plasma and deposition process parameters to achieve the desired attributes and performance of the HA coating, as well as future challenges in clinical applications are also discussed.

Course experiences, satisfaction and career intent of final year pre-registration Australian pharmacy students

Background In Australia, the profession of pharmacy has undergone many changes to adapt to the needs of the community. In recent years, concerns have been raised with evidence emerging of workforce saturation in traditional pharmacy practice sectors. It is not known how current final year pharmacy students’ perceive the different pharmacy career paths in this changing environment. Hence investigating students’ current experiences with their pharmacy course, interaction with the profession and developing an understanding of their career intentions would be an important step, as these students would make up a large proportion of future pharmacy workforce Objective The objective of this study was thus to investigate final year students’ career perspectives and the reasons for choosing pharmacy, satisfaction with this choice of pharmacy as a tertiary course and a possible future career, factors affecting satisfaction and intention of future career paths. Methods A quantitative cross sectional survey of final year students from 3 Australian universities followed by a qualitative semi-structured interview of a convenience sample of final year students from the University of Sydney. Results ‘Interest in health and medicine’ was the most important reason for choosing pharmacy (n=238). The majority of students were ‘somewhat satisfied’ with the choice of pharmacy (35.7%) as a course and possible future career. Positive associations were found between satisfaction and reasons for joining pharmacy such as ‘felt pharmacy is a good profession’ (p=0.003) while negative associations included ‘joined pharmacy as a gateway to medicine or dentistry’ (p=0.001). Quantitate and qualitative results showed the most frequent perception of community pharmacy was ‘changing’ while hospital and pharmaceutical industry was described as ‘competitive’ and ‘research’ respectively. The highest career intention was community followed by hospital pharmacy. Conclusion Complex factors including university experiences are involved in shaping students’ satisfaction and perception of career. This may relate to challenges in the community pharmacy sector, job opportunities in hospital and limited understanding of the pharmaceutical industry. The results offer insight for the profession in terms of entry into various roles and also to pharmacy educators for their roles in shaping curricula and placement experiences that attract future graduates to defined career pathways in pharmacy.

Psychological health of medical and dental students in Saudi Arabia : a longitudinal study

Introduction: Many studies have indicated the poor psychological health of medical and dental students. However, few studies have assessed the longitudinal trajectory of that psychological health at different times in an academic year. Aim: To evaluate the positive and negative aspects of psychological health among preclinical medical and dental students in Saudi Arabia prospectively. Methods: A total of 317 preclinical medical and dental students were recruited for a longitudinal study design from second and third-year students at Umm Al-Qura University in the 2012-2013 academic year. The students were assessed at the middle of the first term and followed up after 3-monthes at the beginning of the second term. Questionnaires included assessment of depression, anxiety, stress, self-efficacy, and satisfaction with life. Results: Depression, anxiety, stress, and satisfaction with life were improved significantly at the beginning of the second term, whereas self-efficacy did not change significantly. The medical, female, and third-year student subgroups had the most significant changes. Depression and stress were significantly changed at the beginning of the second term in most demographic subgroups. Conclusion: Preclinical medical and dental students have different psychological health levels at different times of the same academic year. It is recommended to consider time of data collection when analyzing the results of such studies.