[Investigation of components of seven species of thyme essential oils and comparison of their antioxidant properties]

Background: Thyme is one of the mint family geniuses that belongs to Nepetoideae subfamily. This plant has been known as an antiseptic, antispasmodic and antitussive. Thyme essential oil has many properties that one of which is antioxidant activity

Objective: The aim of this study was the investigation of seven thyme oils and the comparison of their antioxidant activities. In this paper, seven species of thyme essential oils from different regions have been collected and dried

Methods: The essential oil was extracted by using a Clevenger-type apparatus as British pharmacopoeia for four hours. Obtained essential oils were analyzed by gas chromatography-mass spectroscopy [GC/MS] technique

Results: Different compounds were identified in the essential oils with different percentages. The main compound in Thymus daenensis and Thymus vulgaris was thymol with percentage of 43.8 for the former and 45.1 for the latter. The dominate compounds in Thymus migricus, Thymus eriocalyx, Thymus serpylum, Zataria multiflora and Thymus kotschyanus were linalool [41.8%], geraniol [61.8%], para cymene [23.8%], carvacrol [57.7%], and Pulegone [37.2%], respectively. Antioxidant activity of essential oils was measured by 2,2-diphenyl-1-picrylhydrazyl]DPPH] radical scavenging test

Conclusion: Antioxidant activities of Thymus vulgaris, Thymus daenensis, and Zataria multiflora were higher than the other essential oils

[Effect of self-etching and single-bottle bonding systems on shear bond strength of fissure sealant to primary and permanent enamel]

Application of self-etching bonding systems to primary and permanent teeth has increased due to the simplicity of work and fewer steps. This experimental study aimed to compare the effect of conventional acid etching and single-bottle and self-etching bonding systems on shear bond strength [SBS] of light-cured fissure sealant to primary and permanent enamel. In this experimental study, the smoothest unprepared proximal enamel surfaces of 30 primary molars [groups 2, 4 and 6] and 30 permanent premolar teeth [groups 1, 3 and 5] were divided into 6 groups of 10. Groups 1 and 2 [control] were acid-etched and received light-cured fissure sealant [Concise 3M-ESPE]. Groups 3 and 4 [SB] were subjected to acid etching + Single Bondadhesive + fissure sealant. Groups 5 and 6 [PLP] received self-etching bonding system [Prompt L-Pop, 3M, ESPE] + fissure sealant. Specimens were then subjected to 500 thermal cycles with the dwell time of 30 seconds. Shear bond strength was determined using Universal Testing Machine [Zwick, Germany]. Mode of fracture was determined under stereomicroscope and data were analyzed using ANOVA, [between-subjects effect] and LSD. SBS was not significantly different between the control and PLP or SB and PLP groups [P>0.05]. However, the difference in SBS between the control and SB groups was statistically significant [P=0.022]. The SBS in primary teeth was less than in permanent teeth in all groups [P<0.05]. Self-etching bonding system [PLP], similar to conventional acid etching technique, provides adequate bond between the light-cured fissure sealant and unprepared enamel. Application of Single Bond Adhesive effectively increased the fissure sealant bond strength

[-vitro evaluation of the effect of addition of xylitol to carbonated diet soda on enamel microhardness of permanent teeth]

High consumption of carbonated diet soda is the most common etiologic factor for dental erosion. This study aimed to assess the efficacy of addition of Xylitol to carbonated diet soda to prevent enamel micro hardness reduction in permanent teeth. This in-vitro experimental study was conducted on 40 human impacted third molars that had been surgically extracted and were free from caries, erosion, cracks or hypo calcification. For correct measurement of micro hardness, surface of samples was polished with 5000 grit abrasive paper and micro hardness was measured using Vickers micro hardness testing machine. The teeth were then divided into 4 groups and immersed in 40 ml of 4 different solutions for 5 minutes [regular coke as the first control, coke zero, coke zero plus 10 g Xylitol and tap water as the second control]. Understudy surface was a 5x5 mm square on the distal surface of teeth. At the end of experiment, micro hardness of teeth was measured again. Changes in micro hardness were compared in each group with paired t-test and between groups with ANOVA. Based on the obtained results, micro hardness decreased after immersion of specimens in regular coke, coke zero and coke zero plus 25% Xylitol by -38.66 +/- 24.87, -26.1 +/- 16.65 and -19.5 +/- 23.52, respectively and these reductions were statistically significant [P1=0.001][P2=0.001][P3=0.005]. Change in micro hardness was -7.4 +/- 9.17 in specimens immersed in tap water and was not statistically significant [P4=0.5]. The reduction in micro hardness of enamel exposed to Xylitol was significantly less than the other two test groups. Addition of Xylitol to carbonated diet soda reduced the amount of tooth erosion but could not prevent it

[Evaluation of the effect of fluoride gel and varnish on the demineralization resistance of enamel: an in vitro]

Fluoride has an important role in the prevention of caries. This study assessed the efficacy of three types of topical fluoride: fluoride varnish, APF gel [sultan], APF gel [Kimia] in protecting the enamel from demineralization in an in vitro environment. Sixty human caries-free premolars where randomly assigned into four groups of 15 specimens. The control group was washed with deionized/distilled water. Weekly gel [Kimia] was treated with APF gel [1/23%] for 2 minutes weekly, weekly gel [Sultan] was treated with APF gel [1/23%] for 60 seconds weekly, weekly varnish fluoride was treated with Durashield [2/26%]. Specimens were then placed in a cycle of demineralization [pH= 4.3] for 6 hours and remineralization [pH= 7] for 17 hours. This pH- cycle was repeated for 3 weeks [21 days]. The teeth were sectioned buccolingually and evaluated under polarized light microscope. Then the depth of each lesion was measured from the deepest demineralization point of the lesion. The data were analyzed using Kruskal-Wallis and Dunn test for pairwise comparison. The control group had the deepest lesions [mean depth, 140 +/- 37micrometer]. The varnish group had the shallowest lesions [mean depth, 60 +/- 37 micrometer] with a 75.3% reduction percent. However, there was no significant difference in the depth of demineralization between all fluoride treated groups. The difference between fluoride groups and the control group were significant. Treatment of the enamel of permanent teeth with various topical fluorides significantly inhibited demineralization, but there was no significant difference between varnish or gel application

[Dietary fructose and cardiovascular disease risk factors in adults: Tehran lipid and glucose study]

The aim of this study was to investigate the association between fructose intake and cardiovascular disease risk factors in Tehranian adults. This study was conducted using data from adults, aged 19-70 years, who participated in the third phase of Tehran Lipid and Glucose study. Dietary data were collected using a validated semi-quantitative food frequency questionnaire with 168 food items. The sum of natural dietary fructose in fruits and vegetables, and fructose in industrialized foods containing added sweeteners, was calculated as total dietary fructose. Forty-five and fifty-five percent of participants were men and women, with mean ages of 40.5 +/- 13.6 and 38.6 +/- 12.8 years, respectively. Mean dietary intakes of total fructose were 46.5 +/- 24.5 g/d in men and 37.3 +/- 24.2 g/d in women. Significant positive associations were observed between dietary fructose intake and body mass index [beta =0.03 and 0.11, p<0.001, in men and women respectively], systolic blood pressure [beta =0.09 and 0.12, p<0.01, in men and women respectively], diastolic blood pressure [beta =0.13 and 0.80, p<0.01, in men and women respectively] and fasting blood glucose in men [beta =0.01, p<0.05]. Dietary fructose intake may have adverse effects on cardiovascular disease risk factors

Histological evaluation of the pulp of primary teeth after pulpotomy with formocresol and SUAB2

Formocresol is a popular pulpotomy medicament in primary dentition. Because of its systemic and local side effects, it may be essential to use another material instead of formocresol. The purpose of this study was to assess the pulpal response after pulpotomy histologically with two different agents; namely, formocresol and SUAB2. In this randomized clinical trial study, 14 teeth of seven children that should had been extracted because of orthodontic treatment were selected. These teeth were randomly divided into two formocresol and SUAB2 [Shahed University Anti Bleeding 2] groups. Seven teeth were pulpotomized with formocresol and seven teeth with SUAB2. These teeth were extracted after 2 months and the pulpal response was evaluated. Finally, the data were analyzed with exact fisher and Mann-Whitney tests. In the formocresol group, severe inflammation was seen in four teeth, mild inflammation in three teeth, abscess in four teeth, necrosis in two teeth, fibrosis in three teeth and internal resorption in four teeth. In the SUAB2 group, severe inflammation was not seen. Moderate and mild inflammation was seen in four teeth, abscess in two teeth, necrosis in two teeth, fibrosis in three teeth and internal resorption in four teeth. Mann-Whitney test revealed that inflammation is significantly less in the SUAB2 group compared with the formocresol group [p<0/05]. Based on the results of this study, SUAB2 may be used in primary teeth pulpotomy

[Effect of varnish fluoride on prevention of baby bottle tooth decay in 12- 36 months-old babies]

The baby bottle tooth decay is a prevalent type of caries, affecting most of the teeth in deciduous dentition, and it is mostly caused by overnight bottle feeding. Given the importance of implementing preventive procedures, the aim of this study was to determine the effect of varnish fluoride on prevention of baby bottle tooth decay in deciduous dentition. This experimental study was carried out on 52 kindergarten children aged one to three years-old in Tehran. The right maxillary centrals and laterals were considered as cases and the left counterparts as control group. Bifluoride-12 varnish [Voco, Germany] was applied twice over a 6 months period on the buccal and palatal surfaces of 104 case teeth. The results were compared with equal number of control teeth. Cochran-Q, Chi-square and Fisher's exact tests were used for data analysis. After fluoride therapy, 3 [5.77%], 11 [21.16%], and 8 [15.38%] teeth developed new caries in laterals of case groups, centrals and laterals of control groups respectively. None of the centrals in the case group developed new caries. The observed group differences were statistically significant [P<0.001]. According to Chi-square and Fisher's exact tests, factors such as patients' age, gender, geographic region, nutrition habits, oral hygiene and antibiotic consumption had no effect on caries prevalence [P>0.05]. According to the findings of this study, it can be concluded that, fluoride varnish may be considered as effective preventive procedure in nursing bottle caries reduction in children with primary dentition

[Hijama through the passage of time]

Blood-letting is defined to be the withdrawal of blood from a patient. Considering the mysterious, life-saving, and occassionally miraculous nature of blood during the evolving history of man, civilization, and science, this red liquid being the token of life and death throughout centuries was used as evidence for clinical diagnosis of special diseases or otherwise as definite and soothing treatment of patients. Based on the existing evidence, hijama or blood withdrawal in cultural and religious beliefs and customs of certain tribes has had even a special status in saving man from devil or evil forces. The accessible old documents show the expansion of blood drawing as a known life-saving element and treatment method in ancient Egypt, Greece, and Rome in different forms including hijama. However, the development of medical sciences, particularly transfusion medicine and blood transfusion sciences, the treatment and preventive role of hijama and other methods like arteriotomy and leech cupping started to get less prominence except for some eastern countries especially Islamic states where hijama is still employed to relieve soul and treat diseases as a tool of preserving traditions. In Iran, considering the available standards based on which potential blood donors with recent hijama experience are defered for one year, it is necessary to raise awareness of all those involved in the field of blood transfusion and the whole community about the history of hijama so as to see how we can better deal with this historical and traditional controversial topic

[Psychological effects of blood donation on repeat and first time donors in Tehran Blood Transfusion Center]

Provision of adequate and safe blood is the main purpare of Iranian Blood Transfusion Organization. One of the most important and vital strategies to deal with the issue is to replace once donors by repeat donors. Psychological effects of blood donation on frequent and infrequent clients having referred to different blood collection centers in Tehran were considered to be the aim of this study. In the course of this analytic cross-sectional study the standard questionnaire of GHQ was utilized to measure mental health of the participants. All of the donors who had referred to blood collection centers in Tehran during 2004-2005 formed the participants of this research. Data were analyzed with Chi-square, t-test and Man Withney test. Nine hundred thirty five frequent and 749 infrequent donors filled the questionnaire. The level of anxiety and depression in repeated donors was also lower than the other group. The individuals who attempt on blood donation for the first time report their health and physical conditions at a completely acceptable level in order to be accepted as an eligible candidate; however, it is not the same for constant donors, as they do not benefit from this. The return rate of blood donors is very low in case of individuals suffering from high stress. Religious beliefs and the feeling of being beneficial to the society are considered to be important factors both in motivating people to repeat blood donation and protecting against depression. The results of the present study upon publication will also encourage donors to repeat their behavior

[ evaluation on carotid artery calcification on panoramic radiographs of patients over 45 years referred to oral and maxillofacial radiology department of dental faculty of Sha heed Beheshti University [1381] [Research]]

Nowadays brain strokes are the third common cause of death following heart attacks and cancers. Due to the fact that in most cases the occurrence of stroke is associated with severe and long lasting complications, its prevention has been the focus of various investigations the diagnosis of carotid artery calcifications via panoramic radiography are reported to be advantageous. Thus, the present study was designed to evaluate the prevalence of calcified carotid artery among over 45-year - old dental population referred to oral and maxillofacial radiology department of dental faculty Shahed Beheshti University in 1381. In this descriptive study, the data for each patient were recorded in a questionnaire using medical history and interview along with patient's examinations finally, a total of 700 standard panoramic radiographics, taken in the oral and maxillofacial radiology department, were prepared and interpreted by and oral and maxillofacial radiologist. The results of this study showed 52 soft tissue calcified lesions on radiographs, from among them 10 cases were of calcified carotid artery, 7 males and 3 females with the mean age of 64.8 years, ranging from 53 to 81 years. The left carotid artery was involved in 5 cases and the right carotid artery was involved in 3 cases where as in 2 cases both carotid arteries were calcified. Four individuals had no vascular risk factor [Excluding age and sex], while others showed at least one risk factor. Based on this study, the prevalence of carotid arteries calcification was found to be 1.4% in the population under study, 0.2% in the population age ranging from 45-55 years old and 3.1% among the individuals older than 55 years, which are in accordance with other reported studies in this field