Elżbieta Dembowska

Evaluation of alginate as a substitute for root-surrounding tissues in electronic root canal measurements.

Alginate as a substitute for root-surrounding tissue was investigated. The electronic working lengths of root canals under clinical conditions were compared with an in vitro simulation of the same teeth extracted and embedded in alginate. The working lengths in 26 teeth were determined on two occasions using an electronic apex locator, before extraction and after extraction with the same teeth embedded in an alginate mass. The apical 4 mm of the root canals were exposed following the measurements, and the distances between the apical constrictions and the tips of files repositioned in the canals were measured and recorded. The mean distance between the file tip and the constriction was +0.33 mm (±0.38) in vivo and +0.32 mm (±0.30) in vitro. The Wilcoxon signed-rank test indicated that these means were not significantly different. The apical constriction was assessed to be within the limits of 0.5 mm in 80.7% of in vivo cases and in 76.9% of extracted teeth. Statistical analysis demonstrated that there was no significant difference between the results recorded in vivo and in vitro regarding apical constriction localisation. Based on the results of this study, the alginate mass is a useful tool in evaluating the performance of electronic apex locators.

Genetic factors in pathogenesis of diabetes mellitus after kidney transplantation

Posttransplant diabetes mellitus (PTDM) is one of the major metabolic complications after transplantation of solid organs including the kidney. This type of diabetes mellitus affects allograft survival, cardiovascular complications and overall patient survival. The modifiable risk factors that contribute to PTDM include obesity, some viral infections (eg, hepatitis C virus, cytomegalovirus) and especially immunosuppressive drugs including corticosteroids, tacrolimus, cyclosporine and sirolimus. Currently, predisposing genetic factors have been considered important in PTDM development. The commonly evaluated genetic determinants include genes encoding transcription factors, cytokines, chemokines, adipokines, ionic channels, glucose transporters, cytochrome P450 enzymes and other enzymes metabolizing drugs, drug transporters. Unfortunately, the results of studies are inconclusive and differ between populations. There is a need for large genome-wide association study to identify the genetic risk factors associated with PTDM development.

Correlation between the state of periodontal tissues and selected risk factors for periodontitis and myocardial infarction

BACKGROUND The current level of knowledge indicates a relationship between periodontitis and diabetes and/or cardiovascular diseases (CVD). Periodontitis can be not only a risk factor for these diseases, but also a condition modifying other primary risk factors associated with the occurrence of cardiovascular complications (lipid disorders, arterial hypertension, etc.) or diabetes. OBJECTIVES The aim of the study was an analysis of the correlation between the state of periodontal tissues and selected risk factors for myocardial infarction (MI) in patients after recent myocardial infarction. MATERIAL AND METHODS The study included 417 patients (92 women, 325 men) hospitalized due to recent MI. The inclusion criteria were MI history and age below 70 years. The state of periodontal tissues (plaque index, bleeding on probing, pocket depth and clinical attachment loss, CPI index) and selected risk factors for periodontitis and CVD were recorded. RESULTS An analysis of the results showed no statistically significant correlation between the depth, the number, percentage of periodontal pockets and the average clinical attachment level on one hand and BMI on the other hand. Whereas a statistically significant correlation was observed between tobacco smoking and the degree of severity of periodontal diseases measured by the average pocket depth, the number and percentage of pockets above 4 mm and the average clinical attachment loss, as well as between hypertension and the state of oral hygiene and between diabetes and the number of preserved teeth and the number of pockets above 4 mm. CONCLUSIONS The degree of severity of periodontal disease can impact hypertension and diabetes, which could potentially influence the occurrence and course of CVD.

The influence of KIR gene presence/absence polymorphisms on the development of periodontal disease in smokers and non-smokers

Introduction Periodontal diseases are highly prevalent inflammatory, multifactorial diseases. Smoking is one of the most important environmental risk factors for the development and severity of periodontal disease. Killer cell immunoglobulin-like receptors (KIRs) are members of the immunoglobulin (Ig) superfamily and play an essential role in the regulation of NK cell activity, allowing natural killer (NK) cells to sense and respond to human leukocyte antigen (HLA) class I. The aim of this study was to evaluate the influence of KIR gene presence/absence polymorphisms on the development of periodontal disease in smokers and non-smokers. Material and methods This study enrolled 400 Caucasian subjects (age range 25-69 years) from the West Pomeranian region of Poland. The subjects were categorized into four subgroups (smoking and non-smoking patients with periodontal disease; smoking and non-smoking subjects without periodontal disease – control subjects). Results The differences of KIR gene frequencies between non-smoking patients and non-smoking control subjects as well as smoking patients and control subjects were not statistically significant. In multivariate regression analysis advanced age of patients and smoking were independent factors associated with increased frequency of periodontal disease. Conclusions The results of this study suggest that the main factor associated with increased risk of periodontal disease is smoking, whereas KIR presence/absence polymorphism is not a significant factor involved in the pathogenesis of periodontal disease.

Are KIR genes associated with clinical parameters in the course of periodontitis

INTRODUCTION Periodontitis is a common chronic inflammatory disease. It seems that natural killer (NK) cells play a role in the pathogenesis of periodontitis. KIRs are a family of inhibitory or activating receptors expressed on the surfaces of NK cells and some subpopulations of T lymphocytes. The aim of this study was to evaluate the impact of KIR genes on the pocket depth (PD) and clinical attachment loss (CAL) parameter values as markers of disease clinical course. MATERIALS AND METHODS The patients in the study were submitted to anamnesis and to clinical and periodontal examination. The subjects (400) were categorized into two groups: periodontitis (250 including 100 with moderate and 140 with severe periodontitis) and controls (150). Both groups were divided into two subgroups: KIR gene positive (presence of KIR gene in the genome) and KIR gene negative (lack of the KIR gene in the genome). RESULTS The mean value for CAL was more than 5 mm, and the mean value for PD was more than 4 mm in the periodontitis group. The ANOVA test performed for the control group showed that neither PD nor CAL parameters differed between particular KIR-positive and KIR-negative healthy individuals. Similar results were obtained for all subgroups of chronic periodontitis patients and periodontitis patients (moderate as well as severe): no association between KIR genes and PD or CAL parameters was found. DISCUSSIONS The activated immune system is important in pathogenesis of periodontal disease. On the other hand, tissue damage as a response to infection could be due to activation mediated by KIR. In our study no association between either KIR genes presence or absence and PD and CAL parameters was found. Nevertheless, the impact of KIR genes on the clinical course of periodontal disease requires further investigations.