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  • Author: Mirjana Popovska x
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Abstract

Metal-ceramic and all-ceramic prosthetic restorations in the patient mouth are often damaged by esthetic and functional problems that reduce their success and longevity.

Аim: To evaluate methods for testing mechanical characteristics of dental ceramics through analysis of different testing methods.

Material and methods: Dental ceramic materials are tested with in vivo and in vitro methods for their most important mechanical characteristics: hardness, toughness, flexural strength and abrasion. In vitro testing methods are faster and more efficient, without subjective factors from the patient according to ISO standards. Testing is done with universal testing machines, like Zwick 1445, Universal Testing Machine (Zwick DmbH & Co.KG, Ulm, Germany), Instron 4302 (Instron Corporation, England), MTS Sintech ReNew 1123 or in oral chewing simulators.

Results: According to the testing results, flexure strength is one of the most important characteristic of the dental ceramic to be tested, by the uniaxial and biaxial tests. Uniaxial tests three-point and four-point flexure are not most appropriate because the main stress on the lower side of the tested specimens is tension that causes beginning fractures at the places with superficial flow. Uniaxial results for flexural strength are lower than actual force, while with biaxial test defects and flows on the edges of tested specimens are not directly loaded.

Conclusion: Biaxial flexural method has advantages over uniaxial because of real strength results, but also for simple shape and preparing of the testing specimens.

Analysis of Transforming Growth Factor-Beta1 Gene Polymorphisms in Macedonian Patients with Chronic Periodontitis

Background. The existing conflicting data in the literature about the significance of TGF-beta1 polymorphisms in periodontitis.

Aim. To determine whether TGF-beta1 polymorphisms are associated with periodontitis in Macedonian population.

Material and methods. The sample consisted of 301 healthy unrelated individuals, and 132 patients with periodontitis. All individuals were of Macedonian origin and nationality and residents of different regions of the Republic of Macedonia. DNA was isolated from peripheral blood leukocytes by the phenol-chlorophorm extraction method. Cytokine polymorphism genotyping was performed by PCR-SSP (Heidelberg kit). The population genetics analysis package (PyPop) was used for analysis of the data. Crude odds ratios, were calculated with 95% confidence interval.P<0.05 was considered statistically significant.

Results. Significant negative (protective) association between the Macedonian patients with periodontitis and: 1) cytokine genotypes TGF-beta1 cdn 10/C:T and TGF-beta1 cdn 25/G:G; 2) cytokine haplotypes TGF-beta1/TG and cytokine haplotype zygotes TGF-beta1/CG:TG were found. Positive (susceptible) association was found with: 1) cytokine alleles TGF-beta1 cdn 10/C and TGF-beta1 cdn 25/C; 2) cytokine genotypes TGF-beta1 cdn 10/C:C and TGF-beta1 cdn 25/C:G; and 3) cytokine haplotypes TGF-beta1/CC and cytokine haplotype zygotes TGF-beta1/CC:CG.

Conclusion. It is concluded that polymorphisms of TGF-beta1 gene are associated with an increased risk of chronic periodontitis in Macedonian population.

Abstract

Even from the distant past the aesthetic perception in an individual was diminished by the presence of gap between the central incisors. This condition is found under the term “dents du bonheur” or “lucky teeth” and is encountered even among world famous figures including Brigitte Bardot, Eliah Wood, Madonna, Zac Efron, Amy Winehouse and Elton John. The teeth gaps are still considered main reasons for dissatisfaction of the dental patients and reasons for the requirement of aesthetic treatment.

The purpose of this study is to exhibit the influence of the etiological factors in the occurrence of dia-stema mediana classified according to the dominance of their occurrence expressed in percentage values. Materials of this investigation were 100 patients with diastema mediana from the following factors: inheritance, disproportion in the dental arches, inborn or acquired missing teeth, harmful oral habits, high insertion of the labial frenulum as well as mesiodens. After the diagnosis and evaluation of the etiological factor for diastema mediana was performed, a decision regarding the course of treatment was made in direction of the removal of the etiological factor at an early age and orthodontic treatment. The end of the orthodontic treatment in a group of the patients was the beginning of prosthodontic reconstruction.

From our clinical investigation we came to the realization that in 49 patients (49%) the hereditary influence was a dominant factor, next followed disproportions and discrepancies in the dental arch in 14 (14%), inborn or acquired missing teeth in 11 patients (11%), harmful oral habits in 10 (10%), high frenulum insertion in 4 (4%), and pathological objects between central incisors, mesiodens, iatrogenic factors and periodontal disease, in 3 of the clinical cases (3%) each.

We concluded that the occurrence of diastema mediana is multi-causal. The dominant place is occupied by the hereditary factors. With regard to the mutual relationship between the multitudes of factors in the occurrence of diastema mediana, the diagnosis should be made conciliary and the clinical treatment should be interdisciplinary including a prosthodontist, orthodontist and oral surgeon.

Summary

Osteoradionecrosis (ORN) of the jaws is a serious complication of radiotherapy of head and neck malignancies. Different assumptions about its occurring, risk factors and possible therapeutical modalities exist, but the clinical outcome of such patients is still not on the desired level. This article presents a clinical case of ORN of the mandible, occurring with exposed and infected bone, necrotic process that extended through all the mandible body, as well as cutaneous fistula. The first site of ORN was detected 2 years after radiotherapy for oral cancer, with the second one detected 3 and a half years after radiotherapy. In both, the reason for exposing the bone was local trauma due to tooth extraction. Due to the stage of the condition, a decision for surgical treatment accompanied with antibiotics was made.

It is very important and critical for irradiated patients and patients with osteoradionecrosis to perform appropriate oral hygiene and frequent dental checks. Establishing protocols for prevention and treatment, but involving some new strategies regarding to this condition, are strongly recommended.

Summary

Background/Aim: Oral cancer is one of the ten most common cancers in the world, recently positioned as a sixth one, unfortunately with poor prognosis after treatment because of the late diagnostics in advanced stages of the disease. Aim of this study was to present the basic criteria in assessment the accuracy/efficacy, specificity and sensitivity, the positive and negative predicted values of the conventional oral examination (COE) as the easiest and most acceptable procedure in detection of the early changes of the suspicious oral tissue changes compared to the diagnostic gold standard – tissue biopsy in two different groups of examinees.

Material and Methods: Sixty patients divided into two study groups (one with potentially malignant oral lesions and a second consisted of clinically suspicious oral cancer lesions) were examined with COE and subjected to histopathological confirmation - tissue biopsy. All examined patients underwent the diagnostic protocol by the American Joint Commission on Cancer, selected under certain inclusion and exclusion criteria.

Results: Sensitivity of COE in the group of examinees with oral potentially malignant lesions is 83.33%, its specificity is 20.83%, the positive predictive value is 20.83% and the negative predictive value is 83.33%. The accuracy of the COE method is 33.33%. The sensitivity, in the group of patients with oral cancer is 96.43%, specificity is 0%, the positive predictive value is 93.10% and the negative predictive value is 0%. The accuracy of this method is 90%.

Conclusions: The accuracy reaches a value over 90% for the group with lesions with highly suspected malignant potential – oral cancer, and sets the thesis that COE as screening method for oral cancer or premalignant tissue changes is more valuable for the patients with advanced oral epithelial changes, but is recommended to be combined with some other type of screening procedure in order to gain relevant results applicable in the everyday clinical practice.

Abstract

Introduction: The present study aimed to assess the presence of main types of microorganisms involved in the aetiopathogenesis of chronic periodontitis with PCR technique and determinates the presence of composite IL-1 genotype and their associations with founded bacteria.

Material and method: The examined group was consisted from 20 subjects with diagnosed chronic periodontitis and 20 healthy control without periodontitis. Clinical parameters like gingival index (GI), plaque index (PI), bleeding on probing (BOP), periodontal pocket depth (PPD) and clinical attachment lost (CAL) were determinates. Subgingival dental plaque was collected using a sterilized paper point. We used Parodontose Plus test, reverse hybridization kit, for the detection of periodontal marker bacteria, as well as for the detection of composite Interleukin -1 Genotype

Results: The most present bacterial species detected from subgingival dental plaque was Treponema denticola and Porfiromonas gingivalis which was present in 65% of examined patients. In relation to the presence of positive genotype in patients, there was no significant difference between the test and control group for p> 0.05 (p = 1.00). For χ2=8,17 (p=0,06, p<0,05) there is an association between Prevotella intermedia, and composite genotype.

Between positive genotype and analyzed bacterial species A. actinomycetem comitans for p> 0.05 (p = 1.00), P. gingivalis for p> 0.05 (p = 0.16), T. Forsythia for p> 0.05 (p = 0.20), T. Denticola for p> 0.05 (p = 0.64) no association was found.

Conclusion. This investigations confirmed the strong association of these five examined periopathogenes with periodontitis.

Abstract

A simple RP HPLC method for quantification of betamethasone dipropionate (BDP) in gingival crevicular fluid (GCF) has been developed and validated. GCF represents a valuable matrix for therapeutic monitoring of drugs used in the treatment of periodontal disease. The proposed method involves single step extraction for sample preparation. The calibration curve for BDP was linear over the concentration range of 0.10-2.00 μg mL-1 (R2 = 0.9971). RSD values of intra- and inter-day precision ranged 2.2-4.5 and 1.6-5.7 %, while accuracy values were higher than 96.6 and 97.0 %, respectively. The described method can be successfully applied for determination of betamethasone concentrations in GCF obtained from patients with chronic periodontitis after local treatment with BDP cream 0.5 mg g-1.

Abstract

Introduction: One of the most important types of microorganisms in the oral cavity in both healthy and non-healthy individuals is Fusobacterium nucleatum. Although present as a normal resident in the oral cavity, this Gram-negative pathogen is dominant in periodontal disease and it is involved in many invasive infections in the population, acute and chronic inflammatory conditions, as well as many adverse events with a fatal outcome.

Aim: To determine the role of F. nucleatum in the development of polymicrobial biofilms thus pathogenic changes in and out of the oral media.

Material and method: A systematic review of the literature concerning the determination and role of F. nucleatum through available clinical trials, literature reviews, original research and articles published electronically at Pub Med and Google Scholar.

Conclusion: The presence of Fusobacterium nucleatum is commonly associated with the health status of individuals. These anaerobic bacteria plays a key role in oral pathological conditions and has been detected in many systemic disorders causing complex pathogenethic changes probably due to binding ability to various cells thus several virulence mechanisms.

Most common diseases and conditions in the oral cavity associated with F.nucleatum are gingivitis (G), chronic periodontitis (CH), aggressive periodontitis (AgP), endo-periodental infections (E-P), chronic apical periodontitis (PCHA). The bacterium has been identified and detected in many systemic disorders such as coronary heart disease (CVD) pathological pregnancy (P); polycystic ovary syndrome (PCOS), high-risk pregnancy (HRP), colorectal cancer (CRC); pre-eclampsia (PE); rheumatoid arthritis (RA); osteoarthritis (OA).

Abstract

Recurrent aphthous stomatitis (RAS) is a quite frequent, painful, ulcerative disease that affects the lining of the oral cavity and has an unknown etiology. The aim of this article is to examine the impact of the medication proaftol on epithelization speed and severity of pain in patients with RAS. In this randomized, double-blind, placebo-controlled study respondents were divided into two groups where one group was treated with proaftol spray and the other with a placebo. Aphthae considered for treatment had a diameter of 5-6 mm. The participants were given instruction on the use of the spray, two sprayings on the place of the aphtae 3-4 times a day. We examined two parameters in the symptomatology of RAS-lesion size (mm) and pain intensity (noted on four subjective levels: 0-no pain, 1-discomfort, 2-moderate pain, 3-severe pain). These parameters were noted on the baseline, the third, the fifth and the eighth days of examination.

Results: A significant faster reduction of the dimension of aphthous ulcers in patients treated with proaftol 3rd day p < 0.001, 5th day p < 0.0006, 8th day full epithelization in the control group. The magnitude of pain in the experimental compared with the control group on 3rd, 5th and 8th day was also significantly reduced: p < 0.0001, p < 0.007, p < 0.007 respectively.

Conclusion: The use of proaftol positively influences the rate of epithelization and reduction of subjective feeling of pain in patients with RAS. The action of propolis should be the goal of studies with a larger number of subjects.

Abstract

Aim: The present study aimed to investigate the effectiveness of PRF in the treatment of infrabony defects in patients with chronic periodontitis by evaluating the clinical outcome through periodontal depth, clinical attachment level at the baseline, 6 and 9 months post operatively.

Material and Methods: Sixty infrabony defects with probing depth ≥ 5 mm were treated. The inclusion criterion was the necessity for surgical bilateral maxillary treatment. By using split-mouth study design, each patient had one side treated with conventional flap surgery and the other side with conventional flap surgery and PRF. Clinical parameters, such as probing depth (PD) and clinical attachment lost (CAL), were recorded in both groups at baseline, 6 and 9 months post operatively.

Results: Positive effects for all clinical and radiographic parameters were evident in the group with PRF. Mean PD reduction demonstrated statistically significant greater results in the test group (4.00±1.07 mm) compared to the control one (4.83±0.99 mm), p = 0.003 after 9 months postoperatively. After 9 months, there were better results in the test group compared to the control group for CAL (5.60±1.61 mm, 6.20±1.58 mm), but statistically not significant.

Conclusion: Additional use of PRF in the conventional surgical treatment of infrabony defects demonstrated better parameters than the open flap debridement alone.