Showing 13 results for Zand
A. Forozande , F. Aghahosseini,
Volume 1, Issue 3 (10 1987)
Abstract
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AR-SA Granular cell schwanomma is a rare benign tumor
that has been reported sporadically. Our case was a 38 year old man with a pink
to yellow small lump of 5mm in right buccal mucosa without any complaint of
pain or hemorrhage. Microscopic evaluations showed malpighian epithelium with
intense hyperplasia in some parts. In underlying connective tissue a new formed
tissue is seen with cytoplasmic giant cells. Any malignancy was reported. In
this article, clinical and microscopic characteristics as well as misdiagnosis
of the disease are discussed.
A. Forouzandeh ,
Volume 11, Issue 4 (9 1998)
Abstract
The goal of this review was to determine the prevalence of cysts in the oral and maxillofacial regions, specially odontogenic cysts, as determined by age, sex and location.This research reviewed 6826 biopsies from department of oral pathology school of dentistry at the medical sciences university of Tehran from 1360-1376 (1981-1997).The results obtained revealed that 19.48% of biopsy lesions were cysts of osseous structures, of which 81.9% were odontogenic cysts, 12.4% psuedocyst and 5.7% were Non- odontogenic in origin.The most common lesions of the oral cavity were odontogenic cysts of which the subgroup of radicular cysts (which belong to the category of inflammatory odontogenic cysts) consisted of 49.15% radicular cysts occurred with the higher incidence in males in their third decade of life and were found most commonly associated with the upper jaw.Dentigerous cysts fall in the second most common group at 25.71% of odontogenic cysts.These cysts had a male predilection with a peak incidence in the second decade and were most common in the lower jaw.In the third group were the keratinized odontogenic cysts at 19.25%. These cysts had a male predilection with a peak incidence in the third decade and the lower jaws were twice as likely to be involved as the upper jaw. Other types of odontogenic cysts were noted to be less common in occurrence.In this study it was discovered that mcoceles consisted of 63.5% of pseudocysts and were found most commonly in the lower lip, with surgical ciliated cysts at 33.7% were the most common Non- odontogenic cysts and were found exclusively in the upper jaw adjacent to the maxillary sinus.Over all it can be stated that about y5 of all oral and maxillofacial lesions were cysts.The most common cysts were odontogenic cysts which due to their higher prevalence and various types, most be carefully examined at the histopathological level to diagnose and therefore administer definitive treatment.
A. Forouzandeh , G. Rostamali,
Volume 14, Issue 4 (10 2002)
Abstract
Melanoma is a malignant tumor that originates from melanocyte cells. Its oral type is rare. The goal of this investigation was to determine the prevalence of oral malignant melanoma in Iran, as determined by age, sex and location. This research reviewed 623 cases of oral and non-oral malignant melanoma in Immam-Khomeini hospital, Mearaj cancer institute and department of oral pathology of dental faculty, Tehran University of Medical Sciences in a period of 19 years from 1981-1999. The results showed that 54 cases of biopsy lesions were melanoma of oral cavity that included 7.8% of these lesions. The mean age incidence of oral melanoma was 55.5(between 26-86 years). The most prevalent sites were palate (37.1%) and alveolar mucosa (20.4%) and less common sites included floor of mouth. buccal mucosa and tongue.
S. Zand , A. zand ,
Volume 15, Issue 1 (25 2002)
Abstract
Tooth loss is a kind of handicap and losing a number of teeth makes an individual susceptible to this disability. Having knowledge about the prevalence of partial tooth loss, provides us with a better understanding of social hygiene. On the other hand, having access to such an information, students can be led properly to treat more prevalent cases. The goal of this retrospective study is to investigate the frequency of partial prosthesis classifications, among patients, referred to Shiraz dental faculty. Sexuality, tooth loss classification and its reason and the presence of additional space were studied about all patients (371 females, 205 males) from (97-98) to the end of (99-2000). The results showed that females were more than males (64.4%), the lower jaw was treated more than the upper jaw (67.9%), dental caries were the most important reason for extraction (55.5%), class I among females (28.79%) and class II mod I among males (29.73%) had the most frequency, meaning that the most cases were free end, so more attention should be paid for the education of free end partial prosthesis, however, preventive steps should be taken to retain abutment teeth.
A. Pahlavan , M. Ataei , Aa. Zandi-Nejad ,
Volume 18, Issue 2 (4 2005)
Abstract
Statement of Problem: Despite the improvements achieved in the field of dental composites, their strength, longevity, and service life specially in high stress areas is not confirmed. Finding better fillers can be a promising step in this task.
Purpose: The purpose of this study was to investigate the effect of the filler type on the mechanical properties of a new experimental dental composite and compare these with the properties of composite containing conventional glass filler.
Materials and Methods: Experimental composites were prepared by mixing silane-treated fillers with monomers, composed of 70% Bis-GMA and 30% TEGDMA by weight. Fillers were different among the groups. Glass, leucite ceramic and lithium disilicate were prepared as different filler types. All three groups contained 73% wt filler. Comphorquinone and amines were chosen as photo initiator system. Post curing was done for all groups. Diametral tensile strength (DTS), flexural strength and flexural modulus were measured and compared among groups. Data were analyzed with SPSS package using one-way ANOVA test with P<0.05 as the limit of significance.
Results: The results showed that the stronger ceramic fillers have positive effect on the flexural strength. Ceramic fillers increased the flexural strength significantly. No significant differences could be determined in DTS among the groups. Flexural modulus can be affected and increased by using ceramic fillers.
Conclusion: Flexural strength is one of the most significant properties of restorative dental materials. The higher flexural strength and flexural modulus can be achieved by stronger ceramic fillers. Any further investigation in this field would be beneficial in the development of restorative dental materials.
M. Tabrizizadeh , H. Zandi , Z. Mohammadi , A. Molana ,
Volume 20, Issue 3 (4 2007)
Abstract
Background and Aim: Incomplete root development caused by trauma ,caries, or pulpal pathosis requires special attention and treatment . Although calcium hydroxide apexification has been used successfully for years but it requires patient cooperation and multiple appointments . Single visit apexification with MTA has been used in recent years. The purpose of this study was to compare bacterial microleakage of two types of MTA (Made in Iran and Brazil) applied as apical barrier in open apex teeth.
Materials and Methods: 48 single root teeth were used in this experimental in vitro study. Teeth apices were prepared as open apex teeth. For canal obturation the 4mm of root end was filled with 2 types of MTA (white Iranian MTA salami co. Iran and Angelus MTA Angelus Brazil) from coronal access. Teeth were mounted in self-cured acryl and put in BHI microbial culture. A suspension of Staphylococcus epidermidis was injected from coronal area into the root canals.The teeth were incubated and examined every 24 hours for microbial microleakage, indicated as turbidity in culture. Data were analyzed using Fisher exact test with p<0.05 as the level of significance.
Results: Microleakage appeared after 15 days in all Iranian and after 17 days in Angelus MTA samples.There was no significant difference between microleakage of two types of MTA (P = 0.48).
Conclusion: Based on the results of this study, there was no significant difference between microleakage of Iranian and Angelus MTA. If further studies confirm other physical, chemical, biological and sealing properties of Iranian MTA, it could be recommended for clinical application
Mr. Mallakzadeh, A. Zandi, E. Atefi,
Volume 24, Issue 3 (21 2011)
Abstract
Background and Aims: Relative displacement of the implant with respect to bone and quality of bone-implant contact play critical roles in the dental implant stability. The goal of this study was to investigate the dental implant stability using non-linear finite elements method. Therefore, bone-implant relative displacement due to applied force to the implant was calculated, and then an appropriate factor for defining quality of bone-implant contact was presented.
Materials and Methods: In order to develop a three dimensional model and compare the results with clinical studies, computed tomography (CT) scan data of a rabbit tibia was considered as a base. The model was exported to ABAQUS 6.9-1 to be analyzed using nonlinear finite elements method. Dynamic analysis was done on the model using the proper boundary condition and dynamic loads.
Results: Force-displacement curves in bone-implant interface were nonlinear. Friction coefficient, which is a criterion for implant stability and relative displacement, approximately became doubled as the vertical contact force was halved. However, the friction coefficient decreased with reduction of coulomb frictional coefficient.
Conclusion: Friction coefficient, which is calculated upon force-displacement curves, could be considered as a criterion to evaluate the dental implant stability. Decrease of the vertical contact force and also using rough surfaces improved the quality of bone-implant contact and stability of dental implant.
Mahdi Tabrizizadeh, Hengame Zandi, Maryam Kazemipoor, Fatemeh Mokhtari, Abbas Dehghani,
Volume 25, Issue 3 (1 2012)
Abstract
Background and Aims: Calcium hydroxide has a pronounced antimicrobial activity against most of the bacterial species found in infected root canals and endodontic infections. It is one of the most frequently used intracanal medications in endodontic therapy. The objective of this study was to determine the antimicrobial efficacy of six calcium hydroxide formulations (mixed with saline, lidocaine 2%, chlorhexidine 2%, chlorhexidine 0.2%, Iodine Potassium iodide (IKI) 2%, and glycerin) on Enterococcus faecalis using agar diffusion test.
Materials and Methods: Twelve culture plates were incubated with Enterococcus faecalis. Five cavities were made in each plate with 5 mm diameter and 4 mm depth. Two plates were randomly considered for each calcium hydroxide formulation and filled completely with creamy mixture of tested materials. The plates were incubated at 37ºC for 48 hours. The diameter of inhibition zone around each well was recorded in millimetres and data were submitted to ANOVA and Tukey tests.
Results: The results of this study showed that all tested calcium hydroxide pastes had good antimicrobial activity. The antimicrobial activity of calcium hydroxide mixed with lidocaine, chlorhexidine 2% and IKI 2% were significantly greater than that of calcium hydroxide mixed with saline (P<0.001). No significant differences in the antimicrobial were found between the other groups (P>0.01).
Conclusion: Considering the results of this study, lidocaine 2%, chlorhexidine 2% and IKI 2% are suggested to be used for preparation of calcium hydroxide paste. Further studies with different methods are needed for confirming these results.
Fatemeh Mokhtari, Amir Hossein Mansor Abadi, Ali Gharaati Jahromi, Ehsan Anvar, Zandi Hengame, Tabrizi Zade Mehdi, Taghavi Mayam,
Volume 28, Issue 3 (10-2015)
Abstract
Background and Aims: Bacteria and their products have a major role in pulp and periapical diseases. The purpose of this study was to compare the antimicrobial activity of sodium hypochlorite, iodide potassium iodide and chlorhexidine on the enterococcus faecalis after root canal filling.
Materials and Methods: In this experimental study, 95 single canal human teeth were collected. Then after washing and cleaning and filing, the sterilization done using an autoclave. The teeth were smeared with enterococcus faecalis except five which selected as controls and then divided them into 3 groups which A randomly represented the irrigation by sodium hypochlorite, iodide potassium iodide (IKI) and chlorhexidine solution were done. The teeth were filled with gutta-percha and then incubated in a incubator for 90 days at a temperature of 37° C. The specimens were analyzed for Colony Count. Data were analyzed using Kruskal-Wallis test and Chi-Square.
Results: According to the results of this study, the correlation between the 3 groups of cultured teeth were not significant (P=0.812).The specimens which were washed by IKI had the most positive amount of cultures (23.3%) and the specimens which washed by chlorhexidine had the lowest (16.7%).
Conclusion: The results of this study showed that after the use of different wash solutions, no statistically significant difference exist in their antimicrobial activity after root canal therapy.
Fatemeh Mokhtari, Hengame Zandi, Asghar Nafez,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: The presence of microbes inside the canal is the main reason for post-treatment infection. Therefore, the maintenance of the disinfection obtained during the treatment is imperative. The aim of this study was to compare the antimicrobial effect of Tricresol formalin and 5.25% Sodium hypochlorite on the Enterococcus faecalis.
Materials and Methods: In this study 66 human single-rooted extracted teeth were used. After access cavity and root canal preparation, the teeth were sterilized in autoclave, and then contaminated with Enterococcus faecalis suspension and incubated at 37°C for 7 days. Then, they were randomly divided into three groups of 20: In group 1, Tricresol formalin was used as intracanal medicament. In group 2, 5.25% Sodium hypochlorite and in group 3 (control group), normal saline were used as irrigants. 7 days after incubation at 37°C, the microbiological sampling was performed. For this purpose, dentinal shaves were collected from the root canals and cultured in Tryptic Soy Broth, and the number of Colony-Forming Unit (CFU) was counted. Data were analyzed using Kruskal-Wallis and Mann-Whitney tests.
Results: A significant reduction of CFU was observed in the Tricresol formalin and Sodium hypochlorite groups compared to the control group (P<0.001). No significant difference was reported between Tricresol formalin and Sodium hypochlorite groups (P=0.69).
Conclusion: The present study showed that the antimicrobial effect of Tricresol formalin was comparable with 5.25% Sodium hypochlorite on the Enterococcus faecalis.
Fatemeh Mokhtari , Kazem Koopaei, Jalil Modaresi, Hamid Reza Hemati, Hengameh Zandi,
Volume 30, Issue 3 (10-2017)
Abstract
Background and Aims: The purpose of this study was to evaluate the sealing ability of MTA and cold ceramic by using bacterial leakage method.
Materials and Methods: In this experimental study, fifty human single root extracted teeth were chosen. In group A, 20 teeth were filled with MTA and in group B, 20 teeth were filled with cold ceramic. Five teeth were used as a positive control (obturated using gutta-percha without sealer), and five teeth were used as negative control (obturated using gutta-percha with AH26 sealer and coated with two layers of nail varnish). A bacterial leakage model utilizing Enterococcus faecalis was used for evaluation of the sealing ability. The teeth were placed in test tubes, so that they formed two upper and lower compartments. The cultured bacteria in the upper chamber were in contact with the coronal area of the tooth. The root end was placed in the lower chamber containing sterile culture media. In this case, the filling of the root canal was only the communication path between the upper and lower chambers. In this method, the presence of turbidity in the lower chamber indicated that bacteria had penetrated through barrier and reached the medium. The leakage was measured. The acquired data was analyzed using Chi-square test.
Results: In group A (MTA), 7 samples and in group B (Cold ceramic), 4 samples should the leakage. In regarding the leakage, there was no statistically significant difference between MTA and cold ceramic. (P=0.288)
Conclusion: The results showed that the sealing ability of MTA and cold ceramic was similar as root filling materials.
Abdolrahim Davari, Hengameh Zandi, Farnaz Faraahat, Zahra Haddadi,
Volume 34, Issue 0 (5-2021)
Abstract
Background and Aims: Nowadays, new techniques are used to control dental caries that have the ability to kill cariogenic bacteria. Recently, the addition of antibiotics to glass ionomers has been proposed to reduce the overall number of saliva bacteria. The aim of this study was to compare the antimicrobial effect and compressive strength of resin- modified glass ionomer (RMGI) containing different antibiotics on Streptococcus mutans.
Materials and Methods: A total of 120 specimens were prepared in 3 groups (n=40) including RMGI containing doxycycline with a concentration of 1.5%, RMGI containing a combination of ciprofloxacin, metronidazole and minocycline with a concentration of 1.5%, and RMGI without antibiotics as control group. To measure the antibacterial effect, the disk diffusion method and counting of Streptococcus mutans bacterial colonies were used and then the compressive strength test was performed. Data were collected into SPSS25 and analyzed by ANOVA and Kruskal-Wallis tests and the significance level was considered α=0.05.
Results: The mean number of bacterial colonies in the RMGI group containing doxycycline in all three time intervals 1, 24 hours and 7 days was significantly lower than the specimens in the RMGI group containing the triple antibiotic (P<0.001). The mean compressive strength of the two experimental groups was lower than the control group but was not statistically significant (P=0.326).
Conclusion: The addition of antibiotics at a concentration of 1.5% to RMGI resulted in a favorable antibacterial property with no significantly change in the compressive strength.
Fatemeh Mokhtari, Jalil Modaresi, Henghameh Zandi, Iman Ramezanian Nik,
Volume 34, Issue 0 (5-2021)
Abstract
Background and Aims: The need to use a highly effective sealer in order to create a complete seal along the canal is essential for the basic treatment of tooth roots. Therefore, the aim of this study was to investigate the sealing ability of cold ceramic and gutta-percha with sealer by applying the bacterial leakage and electrochemical method.
Materials and Methods: In this in-vitro experimental study, fifty human single-rooted teeth were selected and their crowns were cut from the cervical region. The canals were prepared and washed with 17% EDTA. Then the teeth were randomly divided into four groups: group 1 gutta-percha with AH26 sealer (Dentsply Detrey, Germany) (n=20), group 2 cold ceramic (Yazd, Iran) (n=20), negative and positive control groups which each consisted of 5 teeth. Samples were kept in an incubator at 37° C for 48 hrs. Two coats of nail polish were used for covering the root, except for the last 2 mm, and microleakage in the fillings was measured by the bacterial leakage and electrochemical methods. The microleakage of the two groups was statistically analyzed in the electrochemical technique by Student's t-test, and in the bacterial leakage method by Fisher's exact test.
Results: In bacterial leakage method, in the first group (gutta-percha) 7 samples (35%) and in the second group (cold ceramic) 3 samples (15%) had bacterial leakage, but no significant difference was observed between the two groups on different days (P>0.05). The mean microleakage based on the electrochemical technique in gutta-percha was significantly higher than that of cold ceramic (P=0.0001).
Conclusion: According to the lower microleakage values in the use of cold ceramic compared to gutta-percha, cold ceramic can be used to fill root canals to reduce microleakage, although further studies are needed.
