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Background: Vascular endothelial growth factor (VEGF) is a master regulator and is required for the effective coupling of angiogenesis and osteogenesis supporting both skeletal development and postnatal bone repair. A direct role for VEGF in intramembranous-derived osteoblast growth and differentiation is not clear. We investigated the expression of primary alveolar osteoblast VEGF receptors and the subsequent effects on mineralization and nodule formation in vitro following VEGFR inhibition.Methods: Primary human alveolar osteoblasts (HAOBs) were cultured in the presence of VEGF receptor inhibitors, exogenous VEGF or the bisphosphonate, zoledronic acid. VEGF, VEGFR1 and VEGFR2 mRNA expression and nodule formation following 21 days of culture. VEGFR1 protein expression was examined using immunofluorescence after 48 h.Results: The HAOBs expressed high levels of VEGF and VEGFR1 protein but VEGFR2 was not detected. The VEGFR1/2 inhibitors, ZM306416 and KRN633, lead to a dose-dependent decrease in mineralization. Treatment with zoledronic acid showed no difference in HAOB VEGF receptor expression.Conclusion: VEGF/VEGFR1 pathway appears to be important for intramembranous-derived osteoblast differentiation and maturation in vitro. [ABSTRACT FROM AUTHOR]

Background and Objective: The salivary transcriptome may present as a readily available and non‐invasive source of potential biomarkers. The development of chronic periodontitis is determined by individual patient susceptibility; hence, the aim of this study was to determine the potential of the salivary transcriptome as a biomarker of disease susceptibility using chronic periodontitis as an example. Material and Methods: Using an Oragene® RNA kit, the total RNA was purified from the saliva of 10 patients with chronic periodontitis and 10 patients without chronic periodontitis. The quantity and quality of the total RNA was determined, and a measure of gene expression via cDNA was undertaken using the Affymetrix microarray system. The microarray profiling result was further validated by real‐time quantitative polymerase chain reaction. Results: Spectrophotometric analysis showed the total RNA purified from each participant ranged from 0.92 μg/500 μL to 62.85 μg/500 μL. There was great variability in the quantity of total RNA obtained from the 2 groups in the study with a mean of 10.21 ± 12.71 μg/500 μL for the periodontitis group and 15.97 ± 23.47 μg/500 μL for the control group. Further the RNA purity (based on the A260/A280 ratio) for the majority of participants (9 periodontitis and 6 controls) were within the acceptable limits for downstream analysis (2.0 ± 0.1). The study samples, showed 2 distinct bands at 23S (3800 bp) and 16S (1500 bp) characteristic of bacterial rRNA. Preliminary microarray analysis was performed for 4 samples (P2, P6, H5 and H9). The percentage of genes present in each of the 4 samples was not consistent with about 1.8%‐18.7% of genes being detected. Quantitative real‐time polymerase chain reaction confirmed that the total RNA purified from each sample was mainly bacterial RNA (Uni 16S) with minimal human mRNA. Conclusion: This study showed that minimal amounts of human RNA were able to be isolated from the saliva of patients with periodontitis as well as controls. Further work is required to enhance the extraction process of human mRNA from saliva if the salivary transcriptome is to be used in determining individual patient susceptibility. [ABSTRACT FROM AUTHOR]

Aims: This study investigated the association between the prevalence of oral health problems (caries, gingivitis, mucosal pigmentation and enamel defects in one to 5 year-old children exposed and not exposed to environmental tobacco smoke before and/or after birth. Exposure to environmental tobacco smoke (ETS) in childhood may have significant health effects. Methods: A structured questionnaire was used to collect data on a child's current and previous illnesses, oral health behaviours, dietary habits, parental smoking behaviours and parents' dental history. The intraoral examination recorded dental caries (dmfs), enamel defects, gingival health, melanin pigmentation and soft tissue health. Stimulated saliva was collected. Total sIgA levels were quantified using indirect competitive ELISA with a SalimetricsTM kit. Results: The 44 children (aged 15-69 months) recruited were divided into two groups: ETS and non-ETS (control). There were 22 children in each: 16 who were exposed to ETS during and after gestation were identified as the ETSB subgroup. Participants exposed to ETS were more likely to have had upper respiratory tract and middle ear infections during the neonatal period and had higher mean dmft, mean dmfs, mean percent of surfaces with demarcated opacities and mean GI than the non-ETS participants. The children exposed to ETS before and after birth had the highest occurrence of enamel opacities showed a higher risk for dental caries even though more children in this group used the recommended fluoride toothpaste (1000 ppm fluoride). Mothers who smoked either never breastfed their children or breastfed their children for less than the recommended period of 6 months. Children exposed to ETS were shown to have higher mean total sIgA (μg/ml) than the children in the control group. Conclusions: Associations between ETS exposure before and after gestation and oral health, including salivary changes in young children were shown in the present study. Dental health professionals should include a question about household smoking in children's dental histories, which would allow opportunities to discuss the impact of smoking on child oral health. Longitudinal oral health studies should include a history of maternal smoking during pregnancy and afterwards. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This study aimed to investigate treatment protocols and opinions towards direct pulp capping (DPC) amongst New Zealand (NZ) general dental practitioners (GDP) through a Practice Based Research Network (PBRN) study. DESIGN: Mixed-methods approach using qualitative thematic and quantitative analysis. METHODS: An on-line survey containing Likert scale items and open-ended questions was distributed to GDPs on the Dental Council of New Zealand (DCNZ) register (2012) to collect information on practitioner demographics, treatment protocols, continuing professional development (CPD) and philosophies towards DPC. RESULTs: Two hundred and ten GDPs from North and South Islands providing care in main centres and rural areas engaged with the PBRN and participated in the study. Almost all performed DPC treatment although it was not a common procedure. DPC was perceived as 'successful' or 'very successful' by 95% of respondents, mostly for cases of reversible pulpitis. Most provided DPC for patients of all ages but younger patients were perceived to have the best clinical outcomes. Calcium hydroxide and MTA were the most commonly used materials for DPC. MTA was believed to have the best outcome but cost and handling properties were barriers to its use. The majority of respondents had participated in CPD related to vital pulp therapy and regarded this treatment as conservative and providing time and financial benefits compared with more invasive treatment. Clinicians' timeframes for assessing healing were variable, and combined clinical and radiographic findings were considered most useful. CONCLUSION: New Zealand dentists perceive DPC as a successful and conservative treatment in selected cases. The findings have provided insights into engagement of NZ dentists in using research to inform everyday clinical practice through a PBRN study. [ABSTRACT FROM AUTHOR]

Treatment planning in periodontics, as with any disease, must be based on an understanding of the aetiology and pathogenesis of the disease. In this context, it has slowly become recognized over the past three decades that while plaque is the cause of the disease, it is the innate susceptibility of the host that determines the ultimate outcome of the disease process. Innate susceptibility, in turn, is determined by the nature of the immune response to the specific periodontopathic complexes comprising the plaque biofilm. The aim of this review was to examine current understanding of the immunopathogenesis of chronic periodontitis with respect to its possible clinical implications in terms of treatment planning and risk assessment. Numerous studies have demonstrated that the periodontitis lesion itself involves predominantly B cells and plasma cells, while the gingivitis lesion is primarily a T cell mediated response. This led to the concept over 30 years ago that the development of periodontitis involves a switch from a T cell lesion to one involving large numbers of B cells and plasma cells. It is also well recognized that control of this shift is mediated by a balance between the so-called Th1 and Th2 subsets of T cells, with chronic periodontitis being mediated by Th2 cells. More recently, T regulatory (Treg) and Th17 cells have been demonstrated in periodontal tissues, raising the possibility that these cells are also important in the immunoregulation of periodontal disease. The clinical implications of these observations can be seen in the fact that identification of Th1/Th2 and Treg/Th17 cytokine gene expression in the peripheral blood and salivary transcriptomes is now being trialled as a possible marker of disease susceptibility. If this proves to be the case, a chairside salivary diagnostic could be developed within the next five to 10 years. [ABSTRACT FROM AUTHOR]

The relationship between poor oral health and systemic diseases has been increasingly recognized over the past two decades. Indeed, the clichés “You cannot have good general health without good oral health”, “The mouth is part of the body” and “Floss or die”, are gaining an increasing momentum. A large number of epidemiological studies have now linked poor oral health with cardiovascular diseases, poor glycaemic control in diabetics, low birthweight preterm babies and a variety of other conditions. The majority have shown an association, although not always strong. As a result, a number of meta-analyses have been conducted and have confirmed the associations and at the same time cautioned that further studies are required, particularly with regard to the effect of periodontal treatment in reducing risk. A number of biologically plausible mechanisms have been put forward to explain the association and there is accumulating evidence in support of them, although at this stage, insufficient to establish causality. Nevertheless, the relationship between poor oral health and systemic diseases has become a significant issue, such that adult oral health can no longer be ignored in overall health strategies. This review provides an update on current understanding of the contribution of poor oral health to systemic diseases, the possible mechanisms involved and the relevance of this for general dental practitioners. [ABSTRACT FROM AUTHOR]

Background: Tannerella forsythia (previously T. forsythensis) in subgingival plaque has been recognized as a defined periodontal pathogen, but its mere presence may be insufficient for disease initiation and/or progression. The organism may produce a cysteine protease, encoded by the prtH gene, which may play a role in the transition from commensal organism to opportunistic pathogen. This study aimed to relate changes in the level of T. forsythia prtH genotype over a 5-year period to a concomitant loss of attachment. Methods: Real-time polymerase chain reaction was used to quantify the level of the prtH gene in plaque samples from subjects with and without attachment loss (≥2 mm in at least two sites) over a 5-year period. Clinical measures and subgingival plaque samples were obtained at yearly intervals. Results: Baseline levels of the prtH genotype were significantly lower in the subjects without loss of attachment compared to those who lost attachment over 1, 2, 4, or 5 years. In the subjects with loss of attachment, the higher prtH levels at baseline were not maintained until the end of the observation period Conclusion: Higher levels of the prtH genotype were associated significantly with future attachment loss. [ABSTRACT FROM AUTHOR]

Background, aim: The present study describes (i) the natural distribution of the three putative periodontopathogens Porphyromonas gingivalis, Prevotella intermedia and Actinobacillus actinomycetemcomitans in an Australian population and (ii) the relationship between these organisms, pocket depths and supragingival plaque scores. Methods: Subgingival plaque was collected from the shallowest and deepest probing site in each sextant of the dentition. In total, 6030 subgingival plaque samples were collected from 504 subjects. An ELISA utilising pathogen-specific monoclonal antibodies was used to quantitate bacterial numbers. Results:: A. actinomycetemcomitans was the most frequently detected organism (22.8% of subjects) followed by P. gingivalis and P. intermedia (14.7% and 9.5% of subjects respectively). The majority of infected subjects (83%) were colonised by a single species of organism. A. actinomycetemcomitans presence was overrepresented in the youngest age group but under-represented in the older age groups. Conversely, P. gingivalis and P. intermedia presence was under-represented in the youngest age group but over-represented in the older age groups. Differing trends in the distribution of these bacteria were observed between subjects depending upon the site of the infection or whether a single or mixed infection was present; however, these differences did not reach significance. Bacterial presence was strongly associated with pocket depth for both A. actinomycetemcomitans and P. gingivalis. For A. actinomycetemcomitans, the odds of a site containing this bacterium decrease with deeper pockets. In contrast, for P. gingivalis the odds of a site being positive are almost six times greater for pockets >3 mm than for pockets ≥3 mm. These odds increase further to 15.3 for pockets deeper than 5 mm. The odds of a site being P. intermedia positive were marginally greater (1.16) for pockets deeper than 3 mm. Conclusions: This cross-sectional study in a... [ABSTRACT FROM AUTHOR]