Effects of glycation end-products on the dental pulp in patients with type 2 diabetes.

AIM: This ex vivo study aimed to compare protein expression of advanced glycation end-products (AGE) and receptor (RAGE), and the levels of selected genes associated with inflammation and collagen within dental pulp tissue from patients with type 2 (T2D) diabetes and non-T2D. METHODOLOGY: Noncarious extracted permanent molar teeth from patients with well-controlled T2D (n = 19) and non-T2D (controls) (n = 19) were collected and compared. The coronal pulp was examined using immunohistochemistry (IHC) (n = 10 per group) for anti-AGE and anti-RAGE. Quantitative PCR (n = 9 per group) was used to analyse the gene expression levels of NFKB, S100A12 and COLIA1. Data analyses were performed between the groups using GraphPad Prism using Pearson correlation, Shapiro-Wilk and Mann-Whitney U-tests, and multiple regression using SPSS. RESULTS: AGEs were distributed diffusely throughout the pulp extracellular matrix associated with collagen fibres and were present on several cell types. RAGE was expressed at the pulp-dentine interface and was observed on odontoblasts, immune cells, endothelial cells and fibroblasts. Semi-quantitative analysis of IHC samples showed significantly increased expression of AGE (p < .0001) and RAGE (p = .02) in T2D samples compared with controls. The expression of NFKB (p < .0001), S100A12 (p < .0001) and COLIA1 (p = .01) genes were significantly higher in the T2D pulp, and multivariate logistic regression analysis showed that these findings were not affected by age. CONCLUSION: T2D may exert a similar glycation response in the dental pulp to other body sites. This could occur through activation of NF-κB pathways with a concomitant increase in genes associated with inflammation and collagen.

Diagnosis of oral potentially malignant disorders: Overview and experience in Oceania.

The diagnosis and management of oral potentially malignant disorders (OPMD) should be the same the world over, but there are important nuances in incidence, aetiological factors, and management opportunities that may lead to differences based on ethnogeography. In this review, we update and discuss current international trends in the classification and diagnosis of OPMD with reference to our experience in various regions in Oceania. Oceania includes the islands of Australia, Melanesia (including Papua New Guinea, Fiji, Solomon Islands, Micronesia and Polynesia (including New Zealand, Samoa, Tonga) and hence has diverse populations with very different cultures and a range from well-resourced high-population density cities to remote villages.

Vascular Endothelial Growth Factor A (VEGF-A) and Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) as Potential Biomarkers for Oral Squamous Cell Carcinoma: A Sri Lankan Study.

BACKGROUND: The incidence of oral squamous cell carcinoma (OSCC) is very high in South Asia and Vascular endothelial growth factor (VEGF) is one of the key factors essential for cancer growth. The importance of VEGF-A and VEGF Receptor 2(VEGFR-2) in oral cancer pathophysiology is yet to be decided. Vascular Endothelial Growth Factor A (VEGF-A) is the main factor concerned in angiogenesis in tumors, but its role in Oral Squamous Cell Carcinoma (OSCC) is still debatable. Our study aimed to determine the role of VEGF-A and VEGFR-2 in OSCC. METHODS: Blood from 30 patients with primary OSCC and 1:1 age-sex-matched controls was subjected to qPCR and ELISA to detect VEGF-A gene expression and serum level. Tumors of the 30 patients were investigated for VEGF Receptor-2 (VEGFR-2) expression and were analyzed using Image J software version 1.52 for DAB percentage (DAB-P) area and optical density (OD). RESULTS: VEGF-A relative gene expression among patients was 2.43-fold higher compared to the healthy control group. Well-differentiated had a 1.98-fold increment, while poorly differentiated had a 3.58-fold increment. Serum VEGF-A was significantly elevated among the patients compared to controls (458.7 vs 253.2, p=0.0225). Poorly differentiated had a higher serum VEGF concentration (1262.0±354.7pg/ml) compared with other two. Mean VEGFR-2 DAB-P level in OSCC was 42.41±5.61(p=0.15). Well-differentiated had a DAB-P of 41.20±5.32 while poorly differentiated had DAB-P 46.21±3.78. The mean OD in OSCC was 0.54±0.16. VEGFR-2 OD in well and poorly differentiated OSCC were 0.48±0.12 and 0.68±0.17, respectively. CONCLUSIONS: VEGF-A gene expression, serum levels, and tissue VEGFR-2 levels correlated linearly with the stage and grade of the tumor. This study justifies the value of VEGF-A as a potential biomarker in OSCC in early detection of OSCC. More studies are needed to accept the use of VEGF-A.

Immunohistochemistry and Immunofluorescence.

Immunohistochemistry (IHC) is one of the most widely used protein detection techniques. The principle of this technique is based on the binding of a specific antibody to a matching specific antigen in tissue. The bound antigen-antibody complex then is visualized using a range of detection techniques. IHC uses a number of different enzymatic labels, such as peroxidase and alkaline phosphatase, for the detection of the antigens of interest whereas immunofluorescence (IF) uses a fluorescent signal. In this chapter, IHC will be described using the peroxidase label. Both IHC and IF can be used on formalin-fixed paraffin-embedded (FFPE) or appropriately processed fresh tissues. IHC/IF can be multiplexed to detect more than one antigen at a time, or may be sequentially stained to detect multiple targets. These techniques are routinely used in diagnostic pathology laboratories, not just for diagnostic purposes but many biomarkers are used for patient staging, treatment allocation, and prognostication. Immunofluorescence is routinely used for the detection of antibodies and antigens in freshly biopsied tissues, particularly for immune-mediated and vesiculobullous lesions. In this chapter, the principles of IHC are reviewed followed by examples of IHC and IF staining using readily available antibodies. Steps and processes involved in IHC/IF double staining are also described.

Comparing Two Methods for the Isolation of Exosomes.

Exosomes are membrane-bound nanovesicles released by cells into their extracellular environment. They carry different types of RNA including mRNA which may be useful in the diagnosis of various diseases. Exosome isolation has been a challenge because of their small size; therefore, two exosome isolation methods were compared in this study. The Exoquick-TC PLUS™ exosome isolation kit (kit) was compared with the classic ultracentrifugation (UC) method for exosome isolation. In samples obtained using both methods, cryo-electron microscopy showed round or slightly elongated vesicles with diameters ranging from 50 to 150 nm and delimited by a bilayered membrane. Dynamic light scattering resulted in multiple peaks for kit exosomes, whereas a single peak was observed for UC exosomes. Significantly, more total RNA was present in UC exosomes in contrast to kit exosomes (P < 0.0001). This was reflected in subsequent mRNA analysis using qPCR, where UC exosomes had lower Ct values compared to kit exosomes. In conclusion, exosome characterization revealed the presence of exosomes in both UC and the kit samples. The kit samples presented additional peaks from DLS which might be due to impurities. Overall, due to a higher total RNA and mRNA content, UC is a better option for subsequent mRNA analysis; nevertheless, the kit can still be used if an ultracentrifuge is not available as four out of the five genes selected were detected and quantified using the kit.

The Risk of Oral Cancer among Different Categories of Exposure to Tobacco Smoking in Sri Lanka

Background: The global incidence of oral squamous cell carcinoma (OSCC) is on the rise with no improvement seen in survival rates. Tobacco consumption varies depending on geographic location, ethnicity and culture. The present case-controlled study aimed to determine the relative risk of OSCC for different tobacco consumption patterns in a selected Sri Lankan population. Methods: One hundred and five patients with histopathologically confirmed OSCC attending the National Cancer Institute (Apeksha Hospital) of Sri Lanka and 210 age and gender-matched controls from the community responded to an interviewer-administered questionnaire regarding their smoking and betel-quid chewing (with/ without smokeless tobacco) habits were included in the study. The odds ratios (OR) and 95% confidence intervals (CI) were calculated. p<0.05 was considered as statistically significant. Results: The overall risk of OSCC increased 2.93-fold for smokers. Those smoking two packets of cigarettes or more per day (OR=5.56; 95% CI-2.822- 10.984; p=0.000) had more than double the risk of OSCC than those smoking 1-2 packets per day. Smoking for more than 20 years had a 3.4-fold risk of OSCC. Consumption of betel quid containing tobacco (smokeless tobacco) had a 4.26-fold higher risk for OSCC (OR=4.26; 95% CI-2.21-8.21; p=0.000), and the risk increased when all four ingredients (betel leaf, slaked lime, areca nut, and tobacco) were consumed together (OR=4.26; 95% CI-2.34-7.74; p=0.000). The combined effect from concurrent smoking and betel chewing emerged as the highest risk for OSCC (OR=15.34) which significantly exceeded the risks evident for the two habits practised in isolation from each other. Conclusions: Use of smokeless tobacco, consumption of all four ingredients together, duration of smoking, the number of cigarettes smoked per day and combined consumption of betel quid and smoking are significant risk factors in the development of OSCC among Sri Lankans.

Potentiality and Inflammatory Marker Expression Are Maintained in Dental Pulp Cell Cultures from Carious Teeth.

OBJECTIVES: This investigation aimed to isolate and culture human dental pulp cells from carious teeth (cHDPCs) and compare their growth characteristics, colony-forming efficiency, mineralization potential and gene expression of Toll-like receptors (TLR)-2, TLR-4, TLR-9, tumour necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6, IL-8, IL-17A, 1L-17R, IL-23A, nuclear factor-kappa B (NF-κB), mitogen-activated protein kinase (MAPK1), dentin matrix protein (DMP)-1, dentin sialophospho protein (DSPP), sex determining region Y-box 2 (SOX2) and marker of proliferation Ki-67 (MKi67) with cells isolated from healthy or non-carious teeth (ncHDPCs). METHODS: Pulp tissues were obtained from both healthy and carious teeth (n = 5, each) to generate primary cell lines using the explant culture technique. Cell cultures studies were undertaken by generating growth curves, a colony forming unit and a mineralization assay analysis. The expression of vimentin was assessed using immunocytochemistry (ICC), and the gene expression of above-mentioned genes was determined using quantitative real-time reverse-transcription polymerase chain reaction. RESULTS: ncHDPCs and cHDPCs were successfully isolated and cultured from healthy and inflamed human dental pulp tissue. At passage 4, both HDPC types demonstrated a typical spindle morphology with positive vimentin expression. No statistical difference was observed between ncHDPCs and cHDPCs in their growth characteristics or ability to differentiate into a mineralizing phenotype. ncHDPCs showed a statistically significant higher colony forming efficiency than cHDPCs. The gene expression levels of TLR-2, TLR-4, TLR-9, TNF-α, IL-6, IL-8, IL-17R, IL-23A, NF-κB, MAPK1, DMP1, DSPP and SOX2 were significantly higher in cHDPCs compared with ncHDPC cultures. CONCLUSION: cHDPCs retain their differentiation potential and inflammatory phenotype in vitro. The inflamed tooth pulp contains viable stem/progenitor cell populations which have the potential for expansion, proliferation and differentiation into a mineralizing lineage, similar to cells obtained from healthy pulp tissue. These findings have positive implications for regenerative endodontic procedures.

Type 2 diabetes and the clinically normal pulp: An in vitro study.

AIM: The aim of this study was to investigate the effect of type 2 diabetes (T2D) on clinically normal dental pulp tissue by using special stains and immunohistochemistry (IHC) to determine the morphology of the coronal pulp and distribution of immune markers in non-T2D and T2D groups. METHODOLOGY: Ethics approval for this in vitro pilot study was obtained from the University of Otago Human Ethics Committee (16/069). Twenty extracted permanent molar teeth diagnosed as having clinically normal pulp status were collected. Ten teeth were from participants with well-controlled T2D and ten from participants without diabetes (non-T2D). Each tooth was sectioned transversely at the cemento-enamel junction before the crowns were decalcified and embedded in paraffin. Sections were stained with haematoxylin and eosin, Massons trichrome, and van Gieson stains for histological and morphological evaluation. IHC using anti-CD4, anti-CD68 and anti-CD83 and anti-IL1ß, anti-IL6, anti-IL17, anti-TNF-α, anti-TLR2, anti-TLR4 and anti-FOXP3 identified proteins of interest. Qualitative and semi-quantitative analyses evaluated the morphology of the dental pulp and protein expression. Data analyses were performed with GraphPad Prism, using Student's t-test and multiple regression using SPSS at p < .05. RESULTS: Special stains demonstrated morphological differences in the T2D dental pulp compared with non-T2D. Qualitative analysis indicated that the pulp in the T2D samples was consistently less cellular, less vascular, showed evidence of thickened blood vessel walls, increased pulp calcification and collagen deposition. Semi-quantitative analysis of IHC samples showed the T2D pulp had significantly increased expression of macrophage and dendritic cell markers CD68 (p < .001) and CD83 (p = .04), and there was significantly greater expression of inflammatory cytokines IL1ß (p = .01), IL6 (p < .0001), IL17 (p < .0001) and TNF-α (p = .01). T2D samples showed a significant increase in markers of innate inflammation, TLR2 (p < .001) and TLR4 (p < .001) and decreased expression of regulatory T-cell marker, FOXP3 (p = .01). Multiple regression showed that age-corrected differences were statistically significant. CONCLUSION: Preliminary findings suggest that T2D may exert a similar response in the pulp to complications in other body sites. Hyperglycaemia is associated with changes in the morphology of the clinically normal dental pulp with altered immune cell and cytokine expression.

Immunohistochemical and immunofluorescence expression profile of lymphatic endothelial cell markers in oral cancer.

Lymphangiogenesis makes an important contribution to the tumour microenvironment (TME), but little is known about this in oral squamous cell carcinoma (OSCC). Archival formalin-fixed paraffin-embedded specimens (28 OSCC, 10 inflamed and 6 normal oral mucosa controls) were processed using immunohistochemistry (IHC) with antibodies against lymphatic markers D2-40 (podoplanin), LYVE-1, VEGFR3 and Prox1. After the endothelial cells had been highlighted by the various markers for lymphatic endothelium, the positive stained cells and vessels were identified and counted in a systematic manner to determine microvessel density. Double-labelling immunofluorescence (DLIF) was used to investigate the specificity of D2-40 and LYVE-1 to lymphatic endothelial cells (LECs) as opposed to blood ECs. There was higher D2-40 and Prox1 lymphatic vessel density (P = .001) in the OSCC group when compared with both control groups. Some malignant keratinocytes expressed lymphatic markers, as did a much smaller number of epithelial cells in the control groups. DLIF showed that no vessels co-expressed D2-40/CD34 or LYVE/CD34. Some D2/40+ LVs were LYVE- . D2-40 was the most specific LEC marker in OSCC tissues. These results establish that the OSCC TME contains significantly more lymphatic vessels expressing D2-40 and Prox1 than the control groups, which may play a role in facilitating lymphatic invasion and metastases.

Tobacco Use and Oral Health.

This review outlines the important oral implications of tobacco use. The lining of the mouth (oral mucosa), if exposed to tobacco and its products in a susceptible individual, can develop benign, potentially malignant, and malignant tumours. Treatment and prognosis depend on tumour type, how early it is detected, its size and site in the oral cavity and whether it has spread. Advanced oral squamous cell carcinoma (OSCC) has a 20% 5-year survival rate. Tobacco use also increases the risk of periodontitis, peri-implantitis, caries, alveolar osteitis and halitosis. Although less life threatening than OSCC, these tobacco related conditions create a substantial financial and health burden for individuals and society. Dental practitioners routinely examine the oral cavity for signs of mucosal and tooth changes, are experienced in recognising variations from normal and have established management and referral pathways. They are also ideally positioned to provide brief interventions to assist their patients to quit smoking.

Titanium particles: An emerging risk factor for peri-implant bone loss.

OBJECTIVE: To investigate the presence of titanium particles in peri-implant tissues in cases diagnosed with peri-implantitis, and to identify immunological reactions that these particles may elicit. METHODS: Ten peri-implant tissue biopsies of patients diagnosed clinically and radiographically with peri-implantitis were obtained from the archives of Oral Pathology Centre, University of Otago. The inclusion criteria involves: bleeding on probing, ≥6 mm probing depth and ≥3 mm radiographic bone loss around the dental implant. Peri-implant tissue samples were evaluated using scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDS) to identify of sites with/without titanium particles. Antibodies against human transforming growth factor beta 1 (TGF-ß1), receptor activator of nuclear factor kappa-B ligand (RANKL), interleukin 33 (IL-33) and cluster of differentiation 68 (CD68) were used to stain the specimens. ImageJ software was used to standardise the sampling area, compare and characterise the inflammatory infiltrate in tissues with/without titanium particles. Inflammatory cytokines positivity was assessed using the immunoreactive scores (IRSs). RESULTS: Light microscopy and SEM-EDS analysis identified titanium wear particles in 90% of the tissue samples, associated with a mixed chronic inflammatory infiltrate. Quantification analysis of RANKL revealed significantly higher IRS and intensity scores (p < 0.05) in areas containing titanium. High intensity, proportion and IRSs of TGF-ß1 and IL-33 were observed in areas with titanium. CD68 had higher IRSs in the absence of titanium particles. CONCLUSIONS: Significant overexpression of the cytokine RANKL was observed, with a trend for over-expression of IL-33 and TGF-B1 in areas with titanium. Further studies with large sample size and appropriate control group for quantification analysis is needed to confirm the role of titanium particles in initiating bone loss.

The relative frequency of paediatric oral and maxillofacial pathology in New Zealand: A 10-year review of a national specialist centre.

BACKGROUND: There has been no previous report of the prevalence of paediatric oral and maxillofacial pathology in a New Zealand oral pathology diagnostic service. AIM: The aim of this study was to review cases of paediatric oral pathology to determine relative frequencies of oral lesions in this age group. DESIGN: Paediatric oral pathology cases (≤15 years of age) received between 2007 and 2016 were retrieved from the electronic database of the Oral Pathology Centre, University of Otago. Data collected included diagnoses (categorised into 12 groups), age at diagnosis, and gender. The prevalence of each diagnosis was calculated in terms of percentage of all diagnoses made. Male-to-female ratio and mean age at diagnosis were also determined. RESULTS: A total of 1139 paediatric cases were identified representing 5.2% of all cases. The most common diagnostic group was salivary gland pathology (25.4%), followed by dental (24.8%) pathology. The most prevalent lesion was mucocoele (23%), followed by dental follicle (14.1%). Malignancies were rare with only two cases identified. CONCLUSION: The findings provide an insight into the prevalence of paediatric oral pathology for clinicians. Mucocoele was the most common diagnosis made, suggesting a high prevalence of soft tissue injury as a main presenting concern warranting diagnosis and management through biopsy.

Yeast Species in the Oral Cavities of Older People: A Comparison between People Living in Their Own Homes and Those in Rest Homes.

Oral candidiasis is prevalent among older people due to predisposing factors such as impaired immune defenses, medications and denture use. An increasing number of older people live in rest home facilities and it is unclear how this institutionalized living affects the quantity and type of fungi colonizing these people's oral cavities. Smears and swabs of the palate and tongue and saliva samples were taken from participants residing in rest homes (RH; n = 20) and older people living in their own homes (OH; n = 20). Yeast in samples were quantified and identified by culturing on CHROMagar Candida and sequencing the ITS2 region of rDNA. A higher proportion of RH residents had Candida hyphae present in smears compared to OH participants (35% vs. 30%) although this difference was not statistically significant (p = 0.74). RH residents had, on average, 23 times as many yeast per mL saliva as OH participants (p = 0.01). Seven yeast species were identified in OH samples and only five in RH samples, with Candida albicans and Candida glabrata being the most common species isolated from both participant groups. The results indicate that older people living in aged-care facilities were more likely to have candidiasis and have a higher yeast carriage rate than similarly aged people living at home. This may be due to morbidities which led to the need for residential care and/or related to the rest home environment.

Vascularity and Angiogenic Signaling in the Dentine-Pulp Complex of Immature and Mature Permanent Teeth.

ABSTRACT. OBJECTIVE: This study aimed to examine the protein and gene expression of vascular endothelial growth factor (VEGF) and angiopoietins-1 and 2 in tissue from healthy and inflamed dental pulps. METHODS: Permanent teeth with pulps diagnosed as healthy or reversible pulpitis were used for immunohistochemistry (IHC) and gene expression experiments. For IHC, a whole pulp tissue was excavated from the pulp chamber, and it was formalin-fixed and processed for routine IHC with angiogenic markers anti-VEGF, anti-Ang1, and anti-Ang2. Staining was visualized with diaminobenzidine (DAB), and examined using light microscopy. The distribution of markers in healthy and inflamed pulps was qualitatively and quantitatively analyzed. Real-time quantitative polymerase chain reaction (RT qPCR) was used to ascertain the gene expression levels of ANGPT1, ANGPT2, and TEK in the presence of inflammation. Statistical analysis was performed using the Mann-Whitney test with the statistical significance level set at 0.05. RESULTS: There was increased protein and mRNA expression of VEGF and Ang-1 markers in inflamed pulp samples as compared with that in the healthy pulp tissue. IHC demonstrated intense expression of the VEGF protein on endothelial cells (EC) and some non-ECs, and there was significantly more staining on ECs associated with inflamed tissue (P<0.001). Ang-1 and Ang-2 were significantly expressed on ECs and non-ECs (P<0.05). RT qPCR did not show significant differences in gene expression between healthy and inflamed samples although similar trends were observed to IHC. CONCLUSION: The presence of Ang-1, Ang-2, VEGF, and TEK gene in healthy and mildly inflamed pulp tissue associated with reversible pulpitis indicates that these angiogenic factors may participate in physiological and pathological angiogenesis and healing. The inflammatory process may regulate Ang-1/Ang2/Tie2 signaling; and together with VEGF, these growth factors have an important role in modulating pulp angiogenesis.

Expression of IL33 and IL35 in oral lichen planus.

Oral lichen planus (OLP) is a complex immunological disorder, mediated in part by the release of cytokines by activated T-cells. Recently, the role of novel cytokines including IL33 and IL35 has been described in various chronic inflammatory diseases. IL33, a member of the IL-1 superfamily of cytokines, functions as an 'alarmin' released after cell necrosis to alert the immune system to tissue damage or stress. IL35, a member of IL12 cytokine family, is produced by regulatory T-cells and suppresses the immune response. The expression of IL33 and IL35 is yet to be investigated in OLP. The aim of this study was to determine the presence and topographical distribution of IL33 and IL35 in OLP using immunohistochemistry and quantitative real-time reverse transcriptase polymerase chain reaction (qPCR). For IHC, formalin-fixed paraffin-embedded archival specimens of OLP (n = 10) and a non-specific inflammatory (NSI) control group (n = 9) were used. A double-labelling immunofluorescence technique was used to determine the expression of IL33 and IL35 on CD3+ T-cells. In addition, 12 fresh tissue samples (OLP n = 6 and NSI controls n = 6) were used to determine the gene expression of IL33 and EBI3 (one chain of the dimeric IL35). Quantitative and qualitative analysis was performed with statistical significance set at p < 0.05. IHC showed positive immunostaining with IL33 and IL35 in both OLP and NSI. Comparison of the numbers of IL33+ and IL35+ cells in OLP and NSI did not show any significant difference. In OLP, there were significantly more IL33+ cells in the deeper connective tissue region than at the epithelial-connective tissue interface. Interestingly, all IL35+ cells observed in both OLP and NSI tissues showed ovoid/plasmacytoid morphology. Double-labelling immunofluorescence showed that IL33 and IL35 expression was not localized within CD3+ T-cells. The gene expression experiments showed significantly higher expression of EBI3 (fold regulation 14.02) in OLP when compared to the inflammatory controls. IL33 gene expression was not different between the groups. However, within the OLP tissues, there was a significantly higher expression of IL33 than EBI3. Our data demonstrate the expression of IL33 and IL35 in OLP lesions. Further studies are needed to understand the functional role of these cytokines in OLP pathogenesis.

Vascularity and VEGF/VEGFR2 Signaling in the Dentine-Pulp Complex of Immature and Mature Permanent Teeth.

OBJECTIVE: To examine the microvessel density (MVD) and spatial distribution of endothelial cells and angiogenic activity in immature and mature permanent teeth using immunohistochemistry. METHODS: Healthy third molars with immature and mature root development were formalin-fixed, decalcified in 10% ethylenediaminetetraacetic acid, and processed for routine immunohistochemistry with endothelial cell markers anti-CD34 and anti-CD146 and angiogenic markers anti-vascular endothelial growth factor (VEGF) and anti-VEGF receptor-2 (VEGFR2). Staining was visualized with diaminobenzidine and examined using light microscopy. The distribution of markers was analyzed qualitatively and quantitatively in the coronal, middle, and apical regions of the dentine-pulp complex. RESULTS: There were spatial differences in protein expression for immature and mature teeth. The pulps of immature teeth were more vascular, had a greater number of CD34+ and CD146+ cells, and a significantly higher MVD in the coronal region than those of mature teeth (P=0.03). The apical papilla contained few blood vessels. VEGF/VEGFR2 activity was significantly greater for immature teeth (P=0.001). VEGF was expressed throughout the pulp-dentine complex, but there was significantly more growth factor coronally (immature P=0.04 and mature P=0.02). VEGFR2 was expressed less than VEGF but was seen on the endothelial cells and single cells unrelated to a vessel lumen. CONCLUSION: The spatial distribution of vascular and angiogenic (VEGF/VEGFR2) markers indicates the potential for altered healing responses in the pulps of immature and mature teeth. Immature teeth have a greater MVD and VEGF/VEGFR2 expression than mature teeth, and the increased expression of these markers in the coronal region of both tooth types is important for pulp healing.

Tumor protein 53 mutations are enriched in diffuse large B-cell lymphoma with irregular CD19 marker expression.

Accumulating evidence suggests tumor protein 53 (p53) promotes correct cellular differentiation. Thus, mutant TP53 may be more frequent in tumors with irregular differentiation. This study investigated whether TP53 mutations were more frequent in diffuse large B cell lymphoma (DLBCL) that lacked the B cell lineage marker CD19. Sixteen CD19 negative and 78 CD19 positive DLBCL were sequenced for TP53 mutations. Twenty nine tumors had TP53 mutations and were associated with poorer survival. Mutant TP53 was more frequent in CD19 negative lymphomas (81% versus 21%, p < 0.0001). Analysis of other B cell markers revealed a lack of paired box 5 (PAX5) in CD19 positive lymphomas with mutant TP53 (50%), which was more frequent compared to tumors with wild-type TP53 (15%, p = 0.002). In summary, DLBCL lacking CD19 or PAX5 expression were more likely to have mutant TP53, suggesting irregular B cell marker phenotypes are associated with TP53 mutation.

The nexus between periodontics and oral pathology.

A wide variety of lesions may arise from the oral mucosa, fibrous connective tissue, bone and cementum of the periodontium. The commonest pathology occurs as a result of bacterial infection and is very well known to dentists and periodontists, but rarer conditions present as gingival pathology. The pathogenesis of these conditions ranges from genetic to traumatic to immunological to neoplastic, and includes benign, malignant and metastatic lesions. This paper outlines some of these conditions and describes how the periodontist and oral pathologist can work together using a framework, and how with careful consideration of the clinical features and the use of appropriate special tests, including obtaining an adequate tissue specimen, a timely and accurate diagnosis can be obtained.

Implications of Wear at the Titanium-Zirconia Implant-Abutment Interface on the Health of Peri-implant Tissues.

PURPOSE: To investigate the presence of metallic particles in the peri-implant mucosa around titanium dental implants after 5 years of loading using single-implant crowns with respect to clinical signs of peri-implant inflammation. MATERIALS AND METHODS: Sixteen participants from an ongoing, prospective, single-arm clinical trial who had received titanium dental implants restored with single maxillary crowns veneered to zirconia abutments were available for the study. Exfoliative cytology samples were obtained from the peri-implant tissues and contralateral tooth sites using microbrushes and were evaluated by means of light microscopy (LM), scanning electron microscopy, and energy-dispersive spectroscopy (EDS). Trace elemental analysis was also carried out on the microbrushes using inductively coupled plasma mass spectrometry. Peri-implant and periodontal parameters (plaque, bleeding, attachment level, radiographic bone levels) were recorded. RESULTS: Titanium particles were found in both the single-implant crown and contralateral natural tooth sites. LM and EDS analyses showed significantly higher numbers of Ti particles at the implant-abutment interfaces (mean = 14.168; SD = 2.36) and in the internal aspects of peri-implant mucosa in contact with the prostheses (mean = 4.438; SD = 2.22) when compared with other test and control areas. Mean probing depths were ≤ 3 mm, and no differences were found in plaque or bleeding on probing between implant and tooth sites. Median bone levels were within the normal range for both implant (mesial: 0.5 mm; distal: 0.8 mm) and tooth (mesial: 1.5 mm; distal: 1.8 mm) sites. CONCLUSION: Loading of single-implant zirconia crowns can cause the release of Ti particles because of functional wear at the implant-abutment level. The presence of these metal particles in the peri-implant area did not appear to affect peri-implant health in this patient group.

Multiple cells express interleukin 17 in oral squamous cell carcinoma.

BACKGROUND: Interleukin (IL)-17 is a pro-inflammatory cytokine with pro- and antitumour effects. The aim of this study was to investigate the presence and potential sources of IL-17 in oral squamous cell carcinoma (OSCC). METHODS: Immunohistochemistry was used to label and compare IL-17+ cells in the tissue sections of OSCC and inflammatory controls (IC), n = 14 for both. In OSCC, the comparison was made between the number of IL-17+ cells in the tumoral islands (TI), tumour-stroma interface (TS) and more distant stroma (DS). Cells expressing IL-17 were identified using double-labelling immunofluorescence and examined using laser scanning microscopy. The production of IL-17 from tumour cells was determined in the culture supernatants of OSCC cell lines, SCC4, SCC15 and SCC25, using sandwich ELISA. RESULTS: Significantly more IL-17+ cells were observed in OSCC compared with IC (Mann-Whitney, P < 0.0001). In OSCC, the numbers of IL-17+ cells were not significantly different in three compartments, TI, TS and DS (one-way ANOVA, P > 0.05). However, the TI had significantly fewer IL-17+ cells than the combined stroma (both TS and DS together, Mann-Whitney, P < 0.01). Laser scanning microscopy revealed helper T cells, cytotoxic T cells, macrophages and mast cells co-expressed IL-17. ELISA experiments did not detect IL-17 in the supernatants of OSCC cell lines. CONCLUSIONS: Although the tumour cells themselves did not express IL-17, a range of cell types did, suggesting multiple cellular sources for IL-17 in OSCC. The spatial distribution of IL-17+ cells suggests specific interactions with cells within the tumour microenvironment, implying that IL-17+ cells are likely to play a role in the pathogenesis of OSCC.