Hypercitrullination and anti-citrullinated protein antibodies in chronic apical periodontitis, a laboratory investigation. Does autoimmunity contribute to the pathogenesis?

AIM: The presence of Gram-negative anaerobic bacteria, in particular, Porphyromonas gingivalis (P. gingivalis) in periapical granulomas predicts the generation of citrullinated proteins in the lesion. Citrullination of proteins may lead to the formation of anti-citrullinated autoantibodies (ACPA-s) initiating the formation of an autoimmune loop which may contribute to the perpetuation of inflammatory reactions and tissue damage in chronic apical periodontitis. The objective of this study was to demonstrate the formation of citrullinated proteins in chronic apical periodontitis and whether they can act as autoantigens. METHODOLOGY: Twenty-five periapical granulomas (n = 25) were investigated in the study. Healthy periodontal tissue samples served as normal control tissue (n = 6). The peptidyl-citrulline level was determined with the dot blot method. ACPA levels were analysed using anti-citrullinated cyclic peptide (anti-CCP) EDIA kit. Differences between periapical granuloma and control samples were assessed using Mann-Whitney U tests. p Values <.05 were considered as statistically significant. RESULTS: Protein concentrations, peptidyl-citrulline levels and anti-CCP ratios were compared between periapical granuloma and healthy control groups. Multiple linear regression analysis revealed significant (p = .042) hypercitrullination in periapical granuloma samples. Moreover, there was a significant difference in the ACPA ratios between periapical granuloma (2.03 ± 0.30) and healthy control (0.63 ± 0.17) groups (p = .01). Seventeen of 25 periapical granuloma samples (17/25; 68%), whereas one out of six control samples (1/6; 17%) were shown to be positive for the presence of ACPA. CONCLUSIONS: This is the first study detecting the presence of citrullinated peptides and APCA in periapical granuloma, suggesting the contribution of autoimmune reactions in the pathogenesis and perpetuation of chronic apical periodontitis.

Salivary Chemical Barrier Proteins in Oral Squamous Cell Carcinoma-Alterations in the Defense Mechanism of the Oral Cavity.

Oral squamous cell carcinoma (OSCC) is one of the most frequent types of head and neck cancer. Despite the genetic and environmental risk factors, OSCC is also associated with microbial infections and/or dysbiosis. The secreted saliva serves as the chemical barrier of the oral cavity and, since OSCC can alter the protein composition of saliva, our aim was to analyze the effect of OSCC on the salivary chemical barrier proteins. Publicly available datasets regarding the analysis of salivary proteins from patients with OSCC and controls were collected and examined in order to identify differentially expressed chemical barrier proteins. Network analysis and gene ontology (GO) classification of the differentially expressed chemical barrier proteins were performed as well. One hundred and twenty-seven proteins showing different expression pattern between the OSCC and control groups were found. Protein-protein interaction networks of up- and down-regulated proteins were constructed and analyzed. The main hub proteins (IL-6, IL-1B, IL-8, TNF, APOA1, APOA2, APOB, APOC3, APOE, and HP) were identified and the enriched GO terms were examined. Our study highlighted the importance of the chemical barrier of saliva in the development of OSCC.

[Oral mucositis as the most common complication of childhood cancer therapy. Review of the literature]. / A gyermekkori malignus kórképek kemoterápiájának leggyakoribb mellékhatása, az oralis mucositis. Irodalmi áttekintés.

Mucositis is the most common oral complication of cancer therapy. Oral mucositis in childhood is more frequent and severe compared to adults, especially in children with leukemia. Lesions develop as the chemotherapeutic agents attack the rapidly dividing cells of the oral mucous membrane. Patients may experience trouble in eating, drinking, swallowing or even speaking due to the significant pain caused by the ulceration of the oral mucosa. Oral mucositis has a direct impact on the quality of life and may affect survival. The regular assessment of the oral mucosa is crucial during chemotherapy to evaluate the effectiveness of the oral mucositis prevention and treatment. Several oral mucositis scoring tools have been developed for adults to qualify the symptoms, but there is no universally accepted assessment scale for children. The prevention and treatment of therapy-related mucositis is difficult, though several methods and pharmacologic agents have been tested. Here we discuss the pathogenesis of chemotherapy-induced oral mucositis, the available assessment tools and their applicability to pediatric patients and the available therapeutic and preventive strategies. Orv Hetil. 2018; 159(13): 495-502.

Oral health-related quality of life after prosthetic rehabilitation: a longitudinal study with the OHIP questionnaire.

BACKGROUND: Aspects of oral health related quality of life (OHRQoL) attracted an increased attention recently. OBJECTIVE: The aim of the study was to assess self-reported oral health related quality of life (OHRQoL) among patients requiring prosthetic rehabilitation and to determine the rate of improvement 1 month and 6-12 months after therapy. In addition, effect of age, gender, oral health indicators and denture types before treatment were assessed on OHRQoL as evaluated and reported by the patients. METHODS: Hungarian version of OHIP-49 (OHIP-49-H) questionnaire was completed before oral rehabilitation (T0-phase) by 389 patients undergoing prosthetic replacement. After 1 month (T1-phase) and 6-12 months (T2-phase) recall periods 235 and 92 patients completed the questionnaire. The median interquartile range (IQR) values of the total OHIP-49-H score were calculated for T0-, T1- and T2-phases. Reliability of the questionnaire was checked by Cronbach's statistics. Age, gender, oral health indicators and denture types of patients before and after treatment were recorded and treatment-associated changes in OHRQoL were evaluated. RESULTS: The study demonstrated the excellent reliability and internal consistency of OHIP-49-H by a high and narrow range of Cronbach's alpha value (0.81-0.93). A median OHIP-49-H score of 52; IQR = 25-83 demonstrated a poor OHRQoL on first admission. Decreasing median total OHIP-49-H scores 1 month (24; IQR = 9-51; p < 0.001) and 6-12 months (20; IQR = 7-37; p = 0,055) after therapy indicated an improvement of OHRQoL. Patients' age and CPI value assessed before treatment proved to be significant factors of OHRQoL. CONCLUSIONS: Here we presented representative data about self-assessed OHRQoL of patients requiring prosthetic treatment from Hungary using OHIP-49-H questionnaire. The results demonstrated that the restoration of oral health was associated with an improvement in patients' OHRQoL. According to the demographical and T0 phase clinical status, the treatment was more effective in the respect of OHIP-49-H score improvement among females (than among males), among younger (than among more aged), and among patients with more serious CPI assessed at T0. The type of prosthetic interventions did not exert a significant effect on total OHIP-49-H score, suggesting that the improvement in OHRQoL is independent from the type of denture applied.

Community detection in directed weighted networks using Voronoi partitioning.

Community detection is a ubiquitous problem in applied network analysis, however efficient techniques do not yet exist for all types of network data. Directed and weighted networks are an example, where the different information encoded by link weights and the possibly high graph density can cause difficulties for some approaches. Here we present an algorithm based on Voronoi partitioning generalized to deal with directed weighted networks. As an added benefit, this method can directly employ edge weights that represent lengths, in contrast to algorithms that operate with connection strengths, requiring ad-hoc transformations of length data. We demonstrate the method on inter-areal brain connectivity, air transportation networks, and several social networks. We compare the performance with several other well-known algorithms, applying them on a set of randomly generated benchmark networks. The algorithm can handle dense graphs where weights are the main factor determining communities. The hierarchical structure of networks can also be detected, as shown for the brain. Its time efficiency is comparable or even outperforms some of the state-of-the-art algorithms, the part with the highest time-complexity being Dijkstra's shortest paths algorithm ( O ( | E | + | V | log | V | ) ).

Six-Month Follow-Up of Periodontal Condition in Rheumatoid Arthritis and Ankylosing Spondylitis Arthritis Patients Undergoing Anti-Tumour Necrosis Factor-α Therapy.

In our present study, we aimed to assess the effects of anti-TNF therapy on periodontal condition in a mixed cohort of patients with rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Moreover, we wished to determine whether the baseline dental condition of these patients would affect response to biological therapy. A cohort of 24 arthritis patients was consecutively recruited before starting anti-TNFα therapy. After the dropout of six patients, we evaluated the dental status of 18 subjects at baseline and after 6 months of biological therapy. Clinical responder (R) and non-responder (NR) status was determined after 6 months of anti-TNF treatment. Plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing pocket depth (PPD), PPDmax, clinical attachment loss (CAL), and CALmax were determined. During the 6-month treatment period, six patients (3 RA and 3 AS) terminated the study prematurely as they did not respond to treatment (NR). Therefore, 18 patients were included in the full analysis. There were no major differences in PI, BOP, PPD, PPD max, CAL, and CALmax, among R and NR patients. TNF inhibition resulted in increased GI (0.65 ± 0.34 vs. 0.88 ± 0.30; p < 0.05), as well as decreased PPDmax (4 ± 1.94 vs. 2.72 ± 1.36; p < 0.05) and CALmax (5.22 ± 2.56 vs. 2.72 ± 1.36; p < 0.05) after 6 months. Eight patients had incomplete canal fillings or dead pulps and/or apical periodontitis; six in the R and two in the NR group. In our present study, anti-TNF therapy seemed to worsen the extent of gingival inflammation (GI); however our results also do not support the reduction of mean CPD and CAL as reported by others.

Carboxypeptidase-M is regulated by lipids and CSFs in macrophages and dendritic cells and expressed selectively in tissue granulomas and foam cells.

Granulomatous inflammations, characterized by the presence of activated macrophages (MAs) forming epithelioid cell (EPC) clusters, are usually easy to recognize. However, in ambiguous cases the use of a MA marker that expresses selectively in EPCs may be needed. Here, we report that carboxypeptidase-M (CPM), a MA-differentiation marker, is preferentially induced in EPCs of all granuloma types studied, but not in resting MAs. As CPM is not expressed constitutively in MAs, this allows utilization of CPM-immunohistochemistry in diagnostics of minute granuloma detection when dense non-granulomatous MAs are also present. Despite this rule, hardly any detectable CPM was found in advanced/active tubercle caseous disease, albeit in early tuberculosis granuloma, MAs still expressed CPM. Indeed, in vitro both the CPM-protein and -mRNA became downregulated when MAs were infected with live mycobacteria. In vitro, MA-CPM transcript is neither induced remarkably by interferon-γ, known to cause classical MA activation, nor by IL-4, an alternative MA activator. Instead, CPM is selectively expressed in lipid-laden MAs, including the foam cells of atherosclerotic plaques, xanthomatous lesions and lipid pneumonias. By using serum, rich in lipids, and low-density lipoprotein (LDL) or VLDL, CPM upregulation could be reproduced in vitro in monocyte-derived MAs both at transcriptional and protein levels, and the increase is repressed under lipid-depleted conditions. The microarray analyses support the notion that CPM induction correlates with a robust progressive increase in CPM gene expression during monocyte to MA maturation and dendritic cell (DC) differentiation mediated by granulocyte-MA-colony-stimulating factor+IL-4. M-CSF alone also induced CPM. These results collectively indicate that CPM upregulation in MAs is preferentially associated with increased lipid uptake, and exposure to CSF, features of EPCs, also. Therefore, CPM-immunohistochemistry is useful for granuloma and foam MA detections in tissue sections. Furthermore, the present data offer CPM for the first time to be a novel marker and cellular player in lipid uptake and/or metabolism of MAs by promoting foam cell formation.

[The prevalance of herpesviruses in human apical periodontitis samples]. / Herpeszvírusok elofordulása humán periodontitis apicalis mintákban.

Apical periodontitis is primarily initiated by the endodonto-patogen bacteria spreading from the inflamed or necrotic pulp tissues to the periapical area. Nevertheless, findings within the past years have established a pathogenic role of human herpesviruses such as Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) in periapical inflammations. The authors analysed the prevalence, activity and disease association of EBV, HCMV and human herpesvirus 6 (HHV-6) in 40 apical periodontitis samples and 40 healthy pulp controls. Based on the viral DNA results, EBV (29/40) was the most frequent herpesvirus in apical periodontitis, followed by HHV-6 (8/40) and HCMV (4/40). According to the mRNA results approximately two-third of the EBV DNA-positive lesions had active EBV infections. However, the HHV-6 and the HCMV infections seemed to be of latent state. Our findings suggest that EBV and HHV-GB infections primarily occurred in large sized and symptomatic periapical lesions. The co-occurrence of large lesion size and active EBV infection was strongly associated (OR = 8.80) with the symptomatic manifestation of apical periodontitis.

Salivary miR-31-5p, miR-345-3p, and miR-424-3p Are Reliable Biomarkers in Patients with Oral Squamous Cell Carcinoma.

If not detected early, oral squamous cell carcinoma (OSCC) has very poor prognosis, emphasizing the need for reliable early diagnostics. Saliva is considered a promising surrogate biosample for OSCC detection, because it comes into contact with many cells of the tumor mass, providing a comprehensive sampling of tumor-specific biomolecules. Although several protein- and RNA-based salivary biomarkers have been proposed for the detection of OSCC, the results of the studies show large differences. Our goal was to clarify which salivary microRNAs (miRNA) show reliably high expression in the saliva of OSCC patients, to be used as cancer-specific biomarkers, and potentially as early diagnostic biomarkers. Based on a detailed literature search, we selected six miRNAs commonly overexpressed in OSCC, and analyzed their expression in saliva samples of cancer patients and controls by real-time quantitative PCR. Our results suggest that miR-345 and miR-31-5p are consistently upregulated salivary biomarkers for OSCC, and a three-miRNA panel of miR-345, miR-31-5p, and miR-424-3p can distinguish cancer and control patients with high sensitivity.

[Possible correlations between periodontitis and chronic obstructive pulmonary disease. Review of the literature]. / A fogágybetegség és a krónikus obstruktív tüdobetegség (COPD) lehetséges összefüggései. Irodalmi áttekintés.

Chronic obstructive pulmonary disease (COPD) is a complex, multifactorial inflammatory disease of the airways and the pulmonary parenchyme, caused by infection, air pollution and particles. 4-7% of the adult population is involved. COPD is the 4th-6th common cause of death throughout the world. The main aetiological factor is smoking. Bacteria, such as bacteria from the oral cavity, could play a keyrole in the progression of the disease. Epidemiologic studies have noted a relationship between poor oral hygiene or periodontal bone loss and chronic obstructive pulmonary disease. The prevalence and mortality of the disease is increasing worldwide, the treatment is expensive, the efficiency of the present pharmacotherapy is poor, so the importance of prevention should be increasing. Patients with chronic obstructive pulmonary disease (COPD) are prone to frequent exacerbations which are a significant cause of morbidity and mortality. This review is a short summary of studies about the possible relationship between periodontitis and COPD.

Salivary citrullinated proteins in rheumatoid arthritis and associated periodontal disease.

Periodontal disease (PD) can be an important precipitating factor in the production of citrullinated proteins. Its importance is emphasized, but it is not the only way to produce citrullinated proteins. The aim of the current study was to determine the periodontal conditions and the salivary citrullinated protein content in patients with rheumatoid arthritis (RA) compared to healthy controls. We also wished to correlate citrullinated protein levels in the saliva and serum biomarkers with the periodontal status and temporomandibular joint (TMJ) involvement of patients with RA. Twenty-three patients with RA and 17 healthy controls participated the study. Saliva samples were taken: citrulline content of saliva was measured. Blood test results for patients with RA were collected. TMJ disorders were described. Cariological and periodontal indices were registered. Periodontal conditions and periodontal staging were also registered. Comparison of measured values between groups was performed. Intragroup correlation of patients' values was counted. The prevalence of TMJ complaints was significantly higher in the RA group (8/23) versus controls (1/17). The patients with RA had worse periodontal condition because more patients with RA had gingivitis with a significantly higher bleeding on probing (BOP) (RA: 22.4 ± 25.0%; controls: 6.36 ± 11.6%; p = 0.018). Gingival index (GI) was also significantly higher in the patients than in controls (RA: 0.68 ± 0.58; controls: 0.19 ± 0.38; p = 0.010). The citrullinated protein (relative) content of saliva did not differ significantly (p = 0.147) between patients with RA (1102.2 ± 530.8) and healthy controls (1873.1 ± 1594.9). In RA, the salivary anti-CCP levels positively correlated with PD staging (R = 0.464, p = 0.039) . Control subjects more commonly had healthy gingiva than RA patients. Moreover, in the control group more individuals had intact and reduced height periodontium than periodontitis compared to the RA group. There was no significant difference in the levels of salivary citrulline between patients with RA and controls, despite the significant differences in their periodontal status. Thus, salivary citrulline levels are not associated with RA disease severity.

Effects of articaine and ropivacaine on calcium handling and contractility in canine ventricular myocardium.

BACKGROUND AND OBJECTIVE: In spite of the widespread clinical use of articaine and ropivacaine there is little information available on the effects of these drugs on myocardial Ca handling. In the present study, therefore, the concentration-dependent effects of articaine and ropivacaine on the components of intracellular Ca handling were studied and compared in canine ventricular myocardium. METHODS: Contractility was measured in ventricular trabeculae, [Ca]i transients were recorded from electrically stimulated isolated ventricular myocytes loaded with the calcium-sensitive dye fura-2, L-type Ca current was recorded under whole cell patch clamp conditions, and the release and reuptake of Ca was monitored in sarcoplasmic reticulum vesicles. RESULTS: Articaine and ropivacaine caused a reversible and concentration-dependent decrease in amplitude of the [Ca]i transient (EC50 = 87.4 +/- 12 and 99.3 +/- 17 micromol l, respectively), which was congruent with the reduction obtained for contractility (EC50 = 73.7 +/- 10 and 72.8 +/- 14 micromol l, respectively). No significant change in diastolic [Ca]i was found. L-type Ca current was significantly reduced by articaine and ropivacaine with EC50 values of 327 +/- 56 and 263 +/- 67 micromol l, respectively. Neither Ca release and Ca uptake nor the ATPase activity of the sarcoplasmic reticulum vesicles was altered by articaine or ropivacaine at concentrations less than 200 micromol l. In summary, articaine and ropivacaine caused no significant changes at the therapeutically relevant concentrations of the micromolar range. No significant differences between the effects of articaine and ropivacaine on contractility, [Ca]i transients, L-type Ca current, and sarcoplasmic reticulum Ca release and uptake were observed. CONCLUSIONS: Under conditions of normal application both articaine and ropivacaine are free of cardiodepressant effects; however, a negative inotropic action can be anticipated in cases of accidental intravenous injection or overdose. The observed negative inotropic actions of articaine and ropivacaine are similar in magnitude, and can be mainly attributed to a reduction in net trans-sarcolemmal Ca influx.

[Sterilization in dentistry. Limitations of elastic materials: a case presentation]. / Sterilizálási lehetoségek a fogászatban. Rugalmas anyagok csírátlanításának korlátai egy eset kapcsán.

In everyday dental practice, sterility is essential. Sterilizing different materials can require different methods. In the case of heat sensitive and elastic materials, most common techniques are not suitable because they need to be treated on lower temperature, not to lose their physical properties. For instance, if rubber dam is divested of elasticity, it is useless in restorative dentistry thereafter. Sterilizing rubber dam sheets is not a frequent process, but in certain cases it can be necessary. In such a situation, dentists have to choose between rare and hard-to-reach options. In our referral, we summarize the possibilities of sterilization, focusing on plasma sterilization and hydrogen-peroxide vapor sterilization. During the treatment of our presented case with a deep subgingival fracture line, affecting the crown and the root surface as well, we applied a rubber dam sheet, sterilized with hydrogen-peroxide vapor in order to use adhesive technique. Orv Hetil. 2020; 161(3): 110-115.

Follow-up Study of Microflora Changes in Crevicular Gingival Fluid in Obese Subjects After Bariatric Surgery.

The objective of our study was to investigate the effect of weight loss on the crevicular microflora following bariatric surgery. Crevicular fluid samples were taken from 57 subjects: 22 were in the normal control group; 18 in the obese control group; and 17 patients had had bariatric surgery, who underwent a repeat sampling 6 to 12 months after the operation. Crevicular fluid samples were analyzed by MALDI-TOF MS analysis. After surgery and weight loss, the mean germ count increased, albeit not significantly. Also, Candida albicans and non-albicans Candida species: C. dubliniensis, C. kefyr, and C. lusitaniae appeared after surgery (p < 0.05) in subjects where Neisseria was either absent throughout or eliminated after surgery. However, periodontitis did not develop during this time in our subjects.

Examination of Oral Squamous Cell Carcinoma and Precancerous Lesions Using Proximity Extension Assay and Salivary RNA Quantification.

Saliva is an easy-to access body fluid with high diagnostic potential. The utilization of saliva for oral cancer diagnosis can be an attractive possibility. Besides the oral cancer, it is important to better understand the precancerous lesions such as oral lichen planus (OLP) and leukoplakia (OLK). In order to examine the changes of salivary proteins in controls, patients with oral cancer, and patients with precancerous conditions, proximity extension assay was utilized. Some proteins and functions were characteristic to the examined groups and can serve as a starting point for further biomarker studies. The different nature of OLK and OLP was demonstrated, showing the malignant transformation and the inflammation as the prominent biological processes in the OLK and OLP, respectively. The salivary level of IL6 was verified using quantitative ELISA and the mRNA level was also studied. Elevated IL6 levels could be detected in precancerous groups compared to controls.

4-chloro-orto-cresol activates ryanodine receptor more selectively and potently than 4-chloro-meta-cresol.

In this study we performed the comprehensive pharmacological analysis of two stereoisomers of 4-chloro-meta-cresol (4CMC), a popular ryanodine receptor (RyR) agonist used in muscle research. Experiments investigating the Ca2+-releasing action of the isomers demonstrated that the most potent isomer was 4-chloro-orto-cresol (4COC) (EC50 = 55 ± 14 µM), although 3-chloro-para-cresol (3CPC) was more effective, as it was able to induce higher magnitude of Ca2+ flux from isolated terminal cisterna vesicles. Nevertheless, 3CPC stimulated the hydrolytic activity of the sarcoplasmic reticulum ATP-ase (SERCA) with an EC50 of 91 ± 17 µM, while 4COC affected SERCA only in the millimolar range (IC50 = 1370 ± 88 µM). IC50 of 4CMC for SERCA pump was 167 ± 8 µM, indicating that 4CMC is not a specific RyR agonist either, as it activated RyR in a similar concentration (EC50 = 121 ± 20 µM). Our data suggest that the use of 4COC might be more beneficial than 4CMC in experiments, when Ca2+ release should be triggered through RyRs without influencing SERCA activity.

Role of pathogenic oral flora in postoperative pneumonia following brain surgery.

BACKGROUND: Post-operative pulmonary infection often appears to result from aspiration of pathogens colonizing the oral cavity. It was hypothesized that impaired periodontal status and pathogenic oral bacteria significantly contribute to development of aspiration pneumonia following neurosurgical operations. Further, the prophylactic effects of a single dose preoperative cefazolin on the oral bacteria were investigated. METHODS: A matched cohort of 18 patients without postoperative lung complications was compared to 5 patients who developed pneumonia within 48 hours after brain surgery. Patients waiting for elective operation of a single brain tumor underwent dental examination and saliva collection before surgery. Bacteria from saliva cultures were isolated and periodontal disease was scored according to type and severity. Patients received 15 mg/kg cefazolin intravenously at the beginning of surgery. Serum, saliva and bronchial secretion were collected promptly after the operation. The minimal inhibitory concentrations of cefazolin regarding the isolated bacteria were determined. The actual antibiotic concentrations in serum, saliva and bronchial secretion were measured by capillary electrophoresis upon completion of surgery. Bacteria were isolated again from the sputum of postoperative pneumonia patients. RESULTS: The number and severity of coexisting periodontal diseases were significantly greater in patients with postoperative pneumonia in comparison to the control group (p = 0.031 and p = 0.002, respectively). The relative risk of developing postoperative pneumonia in high periodontal score patients was 3.5 greater than in patients who had low periodontal score (p < 0.0001). Cefazolin concentration in saliva and bronchial secretion remained below detectable levels in every patient. CONCLUSION: Presence of multiple periodontal diseases and pathogenic bacteria in the saliva are important predisposing factors of postoperative aspiration pneumonia in patients after brain surgery. The low penetration rate of cefazolin into the saliva indicates that its prophylactic administration may not be sufficient to prevent postoperative aspiration pneumonia. Our study suggests that dental examination may be warranted in order to identify patients at high risk of developing postoperative respiratory infections.

[The oral lichen planus: doubts and evidence]. / Az orális lichen planus: bizonyosságok és kétségek Irodalmi áttekintés.

Oral lichen planus (OLP) is the oral mucosal form of the lichen ruber planus disease. Its diagnostics is not an easy task. Difficulties exist in diagnosing OLP because there are no fully accepted criteria (neither clinical, nor histological) of the disease. Its etiopathogenesis is also not fully understood. Previous studies concentrated on local factors of the disease such as bad oral hygiene, bad dental condition, and smoking. These studies established that OLP is relatively independent from these factors. Besides local factors, chronic systemic diseases like diabetes and hepatitis of HCV origin were examined. Studies on the parallel occurrence of the OLP with systemic diseases in different populations led to contradictory results. This might strengthen the fact that etiological factors causing the OLP, or worsening the OLP, or playing a role in malignant changes are not the same. Our review would like to provide possible answers to questions concerning OLP.

Effectiveness of Parameters in Quantifying Root Canal Morphology Change after Instrumentation with the Aid of a Microcomputed Tomography.

The objective of this study was to analyse the effectiveness of some parameters which characterise the change in morphology in human root canals subjected to ProTaper rotary enlargement with the help of an X-ray microfocus computed tomography (MCT) and to introduce a novel parameter that is effective in quantifying changes in root canal morphology. Ten each straight and curved root canals with mature apices chosen from extracted human upper incisor and canine teeth were scanned with MCT before and after canal shaping using ProTaper rotary instruments in order to facilitate three-dimensional digital reconstruction and quantitative gauging of relevant instrumental parameters and changes therein (surface area and volume). Root canal geometry change and the effectiveness of shaping were quantified with Structure Model Index change (ΔSMI) and surface area change to volume change ratio (ΔSA/ΔV). These two parameters were also tested on simulated canals. Postinstrumentation cross-sectional changes were also analysed, but only on the plastic blocks. Statistical analysis of parameters was carried out to verify the significance of results. Analysis of cross-sectional shape of postinstrumented resin simulated canals showed statistically significant decrease in Form Factor (p<0.05) and statistically significant increase in Eccentricity (p<0.005). ΔSMI did not show significant difference between straight and curved canals. SMI values showed bidirectional change during root enlargement which questions the reliability of this metric in analysing instrumentation. Statistically significant (p<0.005) deviations in ΔSA/ΔV were quantified as 1.92 and 3.22 for straight and curved human canals, respectively. Instrumentation-induced canal geometry change was determined to be more pronounced in curved canals using the novel parameter ΔSA/ΔV. This has been proven as being a statistically accurate and reproducible parameter for quantitative characterisation of root canal geometry change and differentiation of preparational efficacy for both straight and curved root canals.

Expression of BK channels and Na+-K+ pumps in the apical membrane of lacrimal acinar cells suggests a new molecular mechanism for primary tear-secretion.

PURPOSE: Primary fluid secretion in secretory epithelia relies on the unidirectional transport of ions and water across a single cell layer. This mechanism requires the asymmetric apico-basal distribution of ion transporters and intracellular Ca2+ signaling. The primary aim of the present study was to verify the localization and the identity of Ca2+-dependent ion channels in acinar cells of the mouse lacrimal gland. METHODS: Whole-cell patch-clamp-electrophysiology, spatially localized flash-photolysis of Ca2+ and temporally resolved digital Ca2+-imaging was combined. Immunostaining of enzymatically isolated mouse lacrimal acinar cells was performed. RESULTS: We show that the Ca2+-dependent K+-conductance is paxilline-sensitive, abundant in the luminal, but negligible in the basal membrane; and co-localizes with Cl--conductance. These data suggest that both Cl- and K+ are secreted into the lumen and thus they account for the high luminal [Cl-] (∼141 mM), but not for the relatively low [K+] (<17 mM) of the primary fluid. Accordingly, these results also imply that K+ must be reabsorbed from the primary tear fluid by the acinar cells. We hypothesized that apically-localized Na+-K+ pumps are responsible for K+-reabsorption. To test this possibility, immunostaining of lacrimal acinar cells was performed using anti-Na+-K+ ATP-ase antibody. We found positive fluorescence signal not only in the basal, but in the apical membrane of acinar cells too. CONCLUSIONS: Based on these results we propose a new primary fluid-secretion model in the lacrimal gland, in which the paracellular pathway of Na+ secretion is supplemented by a transcellular pathway driven by apical Na+-K+ pumps.