Sakineh Arami, Sakineh Arami, Masoumeh Hasani Tabatabaei, Seyed Reza Najafzadeh, Ahmadreza Shamshiri, Zohreh Moradi,
Volume 30, Issue 4 (1-2018)
Abstract
Background and Aims: According to many uses of MTA in different treatments, studying about its properties like the setting time, is of great importance. The aim of this study was to compare the initial and final setting time of an Iranian MTA and a foreign MTA.
Materials and Methods: Seven samples were in each group; for measurement of initial and final setting time of MTAs, a mold with dimension of 2×10 mm was prepared. The cements after mixation were put into an incubator with temperature of 37ₒC and humidity of 90%. After mixing of cements, a Gilmore needle with a weight of 100 gr and active tip of 2 mm was used vertically on the surface of MTA for measurement of the initial setting time. Setting was measured by the start of cement mixation to the time the tip of the needle didn’t penetrate to the surface of MTA. For measurement of the final setting time a Gilmore needle with a weight of 456 gr and active tip of 1mm was used vertically on the surface of MTA. The ANOVA test followed by Tukey test was used for comparison of the mean setting time between an Iranian and foreign MTA. The statistical difference was considered significant at the level of 0.05.
Resultes: The mean initial setting time Angelus and Root MTAs were 13.57±0.91 and 11.14±0.92 min, the mean final setting of Angelus and Root MTA, were 48.93±1.54 and 37.86±1.5 min while the initial setting time of Angelus MTA lasted for 0.53±43.2 more min than Root MTA (P=0.001). The final setting time of Angelus MTA took longer for 110.7±0.82 min than Root MTA (P=0.001).
Conclusion: The initial and final setting time of the Iranian MTA was shorter than the foreign one and thus it could a more alternative option in this respect.
Mehdi Abbasi, Aghil Rahmani, Ladan Ranjbar Omrani, Zohreh Moradi, Masumeh Hasani Tabatabaei, Sara Valizadeh,
Volume 31, Issue 3 (11-2018)
Abstract
Background and Aims: Color is the most important and complicated part of aesthetic dentistry. The tooth color matching of restorations is considered as one of the most difficult tasks in the restorative dentistry. The aim of this study to evaluate the effect of two training methods on the dental students’ ability in determining tooth color matching.
Materials and Methods: In this study, 40 dentistry students participated which randomly allocated into two groups. The first group consisted of students who learned teeth color matching methods practically. In the second group, training booklet was used for learning. Using Vita Classic shade guide series, 4 color samples were chosen and the students of each group were asked to determine samples’ color, before, after and one month after the training.
Results: Booklet learning group was more successful in determining fourth color sample. However, in no studied group and no used samples, the results of one month after learning were not better than that of before learning. Also generally, no significant relationship was found between the color matching accuracy, using glasses, and sex of participants.
Conclusion: The use of booklet learning was more effective than practical learning in color matching accuracy for dental students. Also, using glasses and sex were not effective on their color matching accuracy.
Zohreh Moradi, Masumeh Hasani Tabatabaei, Abolfazl Fateh, Mohammad Javad Torkamani, Ladan Ranjbar Omrani, Sara Valizadeh,
Volume 31, Issue 4 (1-2019)
Abstract
Background and Aims: Methicillin-resistant Staphylococcus Aureus (MRSA) is an important infection source in dentistry for different disinfectants to be used to prevent its transmission. Furthermore, a variety of chemical disinfectants are developed to remove bacterial infections from the dental care workers' hands and claims are made regarding their superiority in infection control, although all requires scientific investigations. The aim of present study was to compare the effects of chemical hand-disinfectants Micro Zed HD, Aseptoman and Decosept on MRSA (methicillin resistant staphylococcus aureus) in different periods of time.
Materials and Methods: In this experimental study, the antibacterial efficacy of three hand-disinfectants on standard strain of MRSA (USA300: ATCC® BAA-1717™) was evaluated according to European standard of evaluating antiseptics (EN 1040:2005 CSN EN). First we prepared a 0.5 Mc Farland (108 CFU/ml) suspension of MRSA, and exposed to three disinfectants for 15, 30, 60 and 90 seconds. Then, they were transferred to separate plates of Mueller-Hinton medium and incubated in 37◦C for 24 hours. The plates were compared then with control plate to evaluate the efficacy of materials on bacteria by calculating the CFU/ml of plates.
Results: Three hand-disinfectants evaluated in this study had the maximum anticabterial effect on MRSA in the minimum time of exposure (15 seconds), and we found no trace of growth in any plates.
Conclusion: The three hand-disinfectans (MicroZed HD, Aseptoman and Decosept) in the concentration suggested by their companies, showed no difference in efficacy to remove MRSA from hands.
