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Showing 8 results for Karami

M. Memarian, Mr. Fazeli, H. Jamalifar, S. Karami,
Volume 21, Issue 1 (14 2008)

Background and Aim: According to infection possibility in high risk patients, assessment of microbial contamination in water sources utilized at medico-dental units has become a recent concern. The purpose of this study was to evaluate the microbial contamination in dental units waterlines at the department of operative dentistry, Tehran university of medical sciences in the year 2006.

Materials and Methods: In this cross-sectional study, six dental units in the department of operative dentistry were selected to assess microbial contamination in water sources. Samples were taken on Saturdays (the first working day in a week) and in the midweek, 64 and 16 hours respectively after turning the units off. Moreover, for investigating the effect of flushing, sampling was done at 30, 60, 90 and 120 seconds after flushing and were taken from three parts of each unit including air/water syringe, turbine handpiece and also cup filler water. Samples were transported in closed sterile containers to microbiology laboratory of the school pharmacy. Data were analyzed by Kruskal-Wallis and Dunn tests with p<0.05 as the level of significance.

Results: E.coli was isolated from contaminated samples. Contamination decreased by flushing. In midweek after 90 seconds flushing, water contamination disappeared. On Saturdays 2 minutes flushing decreased contamination to lower that 200 cfu/ml (the rate recommended by ADA). Samples taken from turbine handpieces showed significantly higher contamination rate compared to air/water syringe and cup filler water (p<0.001).

Conclusion: According to the results of this study, dental units waterlines showed bacterial contamination which was eliminated after 120 seconds of flushing.

M. Karami Nogourani, P. Khadem Abbakhshani, Z. Jadidi, G. Amirpoor,
Volume 22, Issue 1 (11 2009)

Background and Aim: Since the clinical studies conducted to explore the effect of bonding agents on the success of fissure sealant are limited in number, the present study was conducted to compare the effects of two bonding agents on the success of fissure sealant of the saliva- contaminated teeth.

Materials and Methods: In this study, 63 teeth of 35 students aged 6-8 with healthy and newly-erupted upper jaw molar teeth, were selected and divided into two groups. In one group, single-bond and In the other, SE bond were used. As the teeth were newly erupted and the distopalatal area being in contact with the gingival sulcus and this fact that, this area was impossible to isolate, the distal sulcus of the contaminated teeth and the mesial area capable of adequate isolation were assumed isolated. For each group, after etching, the teeth on one side were treated with a sealant and the teeth on the other side were first bonded and then treated with the sealant. Hence, four groups were formed: bonded/isolated, bonded/contaminated, controlled/isolated and controlled/contaminated for any bonding agent. The results of the treatment were assessed in terms of the success and failure and then analyzed using Mc Nemar, and Chi-square tests and Cochran.

Results: The results of the study indicated that:1. Saliva contamination caused a significant increase in sealant failures(p<0.05).2. Use of the two bonding agents significantly increased the success of the sealant(p<0.05).3. Use of the two bonding agents significantly increased the success of the fissure sealant on the saliva-contaminated teeth, even more than when the teeth had been isolated and with only fissure sealant(p<0.05). 4. For the contaminated enamel, the results of SE bond were better than those of the single bond (p<0.05). However, in isolated condition the results of using single bond were better (p<0.05).

Conclusion: The results of the study supported the use of these two bonding agents in the treatment of fissure sealants under both isolated and contaminated conditions. Further, more SE bond seemed to be less sensitive to saliva contamination.

Z. Shekaramiz, M. Tabrizizadeh, M. Danesh Ardakani,
Volume 22, Issue 4 (21 2010)

Background and Aims: Insolubility has been stated as one of the important characteristics of the materials which are used as sealers in the endodontic treatments. The aim of this study was to evaluate the solubility of four endodontic sealers (ZOE, Dorifill, AH26 and Tubliseal).

Materials and Methods: Five specimens from each sealer with similar size were prepared. After first weighing, the samples were stored individually in bottles containing 50 ml of distilled water at 37ºC. After 7 days, the specimens weighed and changes in the weight of each sample recorded with a digital scale. The data were analyzed by ANOVA and Post-hoc Tukey HSD tests.

Results: The results of this study indicated that Dorifill had the maximum solubility among all sealers with weight loss of 2.8%. Tubliseal and ZOE showed the weight loss of 1.4% and 2.3%, respectively. AH26 showed weight gain of 1.9% during 7 days. There were no significant differences in the mean weight changes between Dorifill, Tubliseal and ZOE groups (P>0.05). A significant difference was found between the mean weight changes of AH26 and that of the other groups (P=0.000).

Conclusion: From the results of this study, all tested sealers were in the standard limit of solubility, and thus, it could confirm this physical property of sealers for clinical applications.

M. Karami Nogourani, M. Banihashemi,
Volume 23, Issue 1 (22 2010)

Background and Aims: Studies show that sucrose containing chewing gums are cariogenic. The aim of this study was to evaluate the effect of two commercial chewing gums with and without sucrose on dental plaque accumulation compared with the control group.

Materials and Methods: In this clinical study, plaque accumulation during three 7-day periods (with two weeks interval) was recorded (Sillness & Loe Index) in a group of 23 volunteer male dental students who chewed in the first two periods sugar-free or sugar-containing chewing gums (Olips and Orbit, respectively) and in the last period did not chew any gum. Participants were asked to chew daily five gum sticks after meals for about twenty minutes. The data were statistically analyzed using Repeated Measure ANOVA and paired-T test.

Results: The results showed that chewing any gum even sucrose-containing gum decreased the level of dental plaque accumulation (P<0.001). However, the decreasing effect of sugar-free gums was significantly higher (P<0.001).

Conclusion: Although sugar free gum was more effective than sugar containing gum on reducing dental plaque accumulation, chewing even sugar containing gums could decrease the level of dental plaque.

D. Goodarzipur, P. Karami,
Volume 23, Issue 4 (20 2011)

Background and Aims: Caries and bone loss are the most common diseases in oral cavity. The prevalence of these diseases will be reduced by controlling their risk factors. In this study, bitewing radiographs of patients were examined to illustrate the relationship between caries and bone loss.
Materials and Methods: One-hundred and fifty bitewing radiographs of 86 patients were evaluated. In these radiographs, caries and distance between alveolar crest and CEJ were measured. In addition, confounding variables (contact type, tooth type, tooth surface) were assessed. Furthermore, patients were asked about the use of other possible risk factors of bone loss like smoking, brushing, and flossing. The data were analyzed using Regression analysis.
Results: Findings of this study showed that the relationship between caries and bone loss was significant (P=0.02). Also, there were significant relationships between flossing (P=0.03), tooth type (P=0.0001) tooth surface (P=0.02) and bone loss. Finally the multivariate analyses considering confounding variables illustrate significant relationship between caries and bone loss (P=0.0001).
Conclusion: Caries and bone loss have important roles as the risk factors for each other. Thus, it is necessary to prevent these risk factors and treat them as soon as possible to reduce these diseases.

, Manoochehr Karami, Ghodrattollah Roshanaei, Abbas Shokri, Namdar Pasandi,
Volume 29, Issue 4 (1-2017)

Background and Aims: Acurate measurements of variables are crucial in epidemiological studies. Therefore, even the best design cannot prevent bugs caused due to the lack of reliability and validity measurement in studies. The aim of this study is to determine the validity of teeth-canal measurement.

Materials and Methods: This methodological study used available data of patients referred to dental clinics at Hamadan University of Medical Sciences in Hamadan with sample size or 58 cases in 2012. In order to determine the reliability of measuring the length of canals and introduce the most appropriate measure met of the actual data, Bland-Altman plot and intraclass correlation coefficient (ICC) were used and finally compared.

Results: In this study, the mean ± SD of channel length in the apex locator Root ZX were 21.93 ± 2.28 mm and in X-ray PA were 22.4 ± 2.38 mm. ICC between the length of canals by the apex locator and radiographic in all teeth was 0.989. Bland-Altman plot showed that absolute agreement between the two methods of measurement.

Conclusion: The findings of this study ensure dental professionals that measuring the length of channels by PA method is more practical and easier and prove different approaches of the reliability and validity. However, we recommend using ICC and Bland Altman methods due to their informative nature and consideration of absolute agreement instead of consistency.

Abdolrahim Davari, Alireza Daneshkazemi, Mahsan Sheshmani, Haleh Karami, Elham Motallebi,
Volume 32, Issue 3 (11-2019)

Background and Aims: The bleaching agents can lead to color and translucency changes in composite resins. Due to the increasing use of the nano composites and the silorane-based composites, this study aimed at examining the color and translucency changes of these restorations after bleaching agents.
Materials and Methods: In this experimental - laboratory study, 198 composite discs were divided into three groups of 66 specimens using three types of composite: the microhybrid composite Z250, the nanohybrid composite Z350 and the silorane-based composite P90. After acid etching, half of the specimens in each group were covered by a resin rebounding agent. Then, the color and translucency assessment was done by reflectance spectrophotometer, using CIE LAB system. Each group was divided into three subgroups of bleaching agents: the 40% hydrogen peroxide and 20% carbamide peroxide bleaching agents and the control group. After applying bleaching agents, the final color and translucency changes were assessed. Data were analyzed using Mann Whitney and Kruskal Wallis tests.
Results: The effect of composite and bleaching agent type and bonding agent were significant (P<0.001). The color changes in the microhybrid composite were higher than nanohybrid and silorane-based composites (P<0.001) (∆E>3.3). Also, the color changes by 20% carbamide peroxide were higher than that of hydrogen peroxide and control groups (P<0.001). The results of translucency changes were generally consistent with color-change measurements (∆E>3.3).
Conclusion: According to the present study, the most color changes appeared in the microhybrid composite and by 20% carbamide peroxide bleaching agent. Rebound samples were generally less affected by bleaching agents. The least color and translucency changes were related to nanohybrid composites.

Azadeh Zakerzadeh, Abdolrahim Davari, Haleh Karami,
Volume 33, Issue 2 (8-2020)

Background and Aims: The self-adhering composites were introduced to reduce the chair time and minimizing handling errors. They can be bonded micromechanically to the dental structure without the need for separate adhesive application. Since there is limited information about bonding performance of this type of composite, the aim of this study was to evaluate the microleakage of enamel and dentin margins compared to the conventional adhesive systems.
Materials and Methods: 30 intact premolars were selected and on their buccal and lingual surfaces, standardized class V cavities with the occlusal margin in enamel and gingival margin in dentin were prepared. Then according to the materials used, the specimens were randomly divided into three groups including: 1) Vertise flow, 2) SE bond + ValuxTM Plus, and 3) Single bond + ValuxTM Plus. After final polishing of the restorations, the specimens were subjected to 1000 thermal cycles of 5±2 and 55±2°C and after that dye penetration was examined by stereomicroscope. The collected data were statistically analyzed using Kruskal-Wallis test and Mann-Whitney test
Results: The lowest rate of the occlosal microleakage was related to group 2 (P<0.05) and there was no significant difference between groups 1and 3 (P=0.58). Also, no significant difference was found in the gingival microleakage among the three groups (P=0.23). On the other hand, in each group, the gingival microleakage was significantly higher than occlosal margins (P<0.05).
Conclusion: According to the results, sealing ability of self-adhering composite is comparable with that of the conventional adhesives.

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