Showing 214 results for Ali
M. Zarabian , M. Aligholi , N. Shokouhi Nejad ,
Volume 18, Issue 3 (11 2005)
Abstract
Background and Aim: Today several materials have been used for root- end filling in endodontic surgery. Optimal properties of Pro Root MTA in in-vitro and in-vivo studies has been proven. On the other hand, based on some studies, Root MTA (Iranian Pro Root MTA) and Portland cement are similar to Pro Root MTA in physical and biologic properties. The aim of this study was to evaluate bacterial leakage (amount and mean leakage time) of four root- end filling materials.
Materials and Methods: In this experimental in-vitro study, seventy six extracted single- rooted human teeth were randomly divided into six groups for root-end filling with gray Pro Root MTA, white Pro Root MTA, Root MTA (Iranian Pro Root MTA), Portland Cement (type I) and positive and negative control groups. Root canals were instrumented using the step- back technique. Root- end filling materials were placed in 3mm ultra sonic retro preparations. Samples and microleakage model system were sterilized in autoclave. The apical 3-4 mm of the roots were immersed in phenol red with 3% lactose broth culture medium. The coronal access of each specimen was inoculated every 24h with a suspension of Streptococcus sanguis (ATCC 10556). Culture media were observed every 24h for colour change indicating bacterial contamination for 60 days. Statistical analysis was performed using log- rank test with P<0.05 as the limit of significance.
Results: At the end of study 50%, 56.25%, 56.25% and 50% of specimens filled with Gray Pro Root MTA, White Pro Root MTA. Root MTA and Portland Cement (type I) had evidence of leakage respectively. The mean leakage time was 37.19±6.29, 36.44±5.81, 37.69±5.97 and 34.81±6.67 days respectively. Statistical analysis of data showed no significant difference among the leakage (amount and mean leakage time) of the four tested root- end filling materials (P=0.9958).
Conclusion: Based on the results of this study, there were no significant differences in leakage among the four tested groups at 60 days. The results suggest that Root MTA and Portland Cement can be used as less expensive root filling materials.
S. Arami , M. Tavassoty Kheiri , R. Bashar , Ma. Nadali ,
Volume 19, Issue 1 (3 2006)
Abstract
Background and Aim: Infection control is an important issue in dentistry. Without an efficient infection control, pathogens left on instruments and working surfaces will have potential danger to patients’ health. In this research, antiviral effect of three disinfectants: 0.5% sodium hypochlorite 0.05% sodium hypochlorite and Deconex 50 AF, on HBV was investigated.
Materials and Methods: In this interventional (before-after) study serums of 26 HBV positive patients were analyzed by PCR HBV analysis and 9 contaminated species were obtained to test three disinfectants. 36 agar plates were prepared with the contaminated serums. 27 of the plates were disinfected in 3 separate groups with the above mentioned solutions. Nine remaining plates were not disinfected (control). Swabs wetted by BSAS (Bovine Serum Albumin Sodium Chloride) medium were applied on the surface of the plates and the were kept in the transferred medium and sent to virology-lab of Pasteur Institute. HBV DNA were detected by commercial kit of HBV PCR (polymerase chain reaction) method. Data were analyzed by Cochrane test with p<0.05 as the limit of significance.
Results: None of samples disinfected with 0.5% sodium hypochlorite showed contamination. 11/1% of samples disinfected with 0.05% sodium hypochlorite and 44/4% of samples disinfected with Deconex 50 AF remained contaminated. Statistical analysis showed a significant difference between 0.5% sodium hypochlorite and the other groups.
Conclusion: Our findings revealed that 0.5% sodium hypochlorite solution is a strong and efficient disinfectant against HBV. Key Words: HBV Sodium hypochlorite
Z. Dalili , S. Rahro Taban , Ma. Vahedi ,
Volume 19, Issue 2 (4 2006)
Abstract
Background and Aim: Adenoids are normally large in children and their size starts to reduce during adolescence. Hypertrophic adenoids could be associated with allergic reactions. Enlarged adenoids result in nasal breathing difficulties and the child is forced to switch to mouth breathing. Airway obstruction causes postural alterations of jaw, tongue and head, and due to persistent obstruction, patient’s appearance changes to adenoid face. Evaluation of nasopharyngeal space in lateral cephalometic view is a simple and repeatable method for determination of the size and shape of adenoids and nasopharyngeal space which can provide a simple measurement of nasopharyngeal obstruction. The roof of nasopharyngeal space is covered by the sphenoid bone. Thus changes of nasorespiratory resistance by hypertrophic adenoids may affect the cranial base angles. In this study, the relationship between adenoid hypertrophy and cranial base angles was investigated.
Materials and Methods: In this descriptive-analytic study, lateral cephalometric views of 7 to 14 y/o patients from the files of orthodontic centers in Rasht city were selected. The radiographs with proper resolution were separated for this research. Adenoid to nasorespiratory ratio (A/N Ratio) was determined by Fujioka method and categorized in three groups: A (A/N 0.8), B (0.5
L. Eslamian , B. Eslami , M Lotfalian ,
Volume 19, Issue 2 (4 2006)
Abstract
Background and Aim: Orthodontic ligature cutting pliers are expensive. Methods of sterilization should be safe considering patients' health as well as lifetime of orthodontic pliers. The purpose of this study was to compare the wear of orthodontic ligature cutting pliers after sterilizing with dry heat or steam autoclave.
Materials and Methods: In this experimental study, thirty ligature cutting pliers from 3 different factories (Dentarum-Germany, RMO and ETM-USA) were sterilized in either dry heat or steam autoclave. The amount of wear at the tip of each plier in both groups was measured with a stereomicroscope and digital photomicrography. Wear was defined as the difference of the initial length and the length after 10, 20, 30 cycles of sterilization measured by the distance from a reference line on the tip of the plier. Three way ANOVA was used to compare wear between the two sterilization groups. P<0.05 was considered as the limit of significance.
Results: The amount of wear of the ligature cutting pliers' tip after 10, 20 and 30 cycles in dry heat sterilization was 1.0±0.16, 0.98±0.22 and 0.94±0.31 mm respectively. These figures were 1.16±0.15, 1.16±0.13 and 1.15±0.14mm for steam heat sterilization. The higest wear was observed after 20 cycles of sterilization in autoclavce whereas the lowest was seen in dry heat sterilization after 30 cycles. The differences between the two studied groups were statistically significant (P<0.0001). In addition, increasing sterilization cycles decreased the rate of wear in both groups.
Conclusion: Based on the results of this study routine autoclaving caused more damage and wear at the tip of the pliers than dry heat sterilization.
Sh. Shahrabi , Mt. Lotfalian ,
Volume 19, Issue 2 (4 2006)
Abstract
In this paper, an unusual case of pigmented dentigerous cyst in a 37-year-old Iranian man with multiple dentigerous cysts of maxilla and mandible is reported. In addition to the characteristic histopathologic features of dentigerous cyst, numerous melanin granules which were distributed throughout the epithelial lining of one of these cysts were also noted. The histochemical study using Fontana’s staining indicated that the pigment was melanin and many of the cells containing melanin were immunohistochemically positive for S-100 protein. Although no firm conclusion could be drawn from the present case regarding melanin origin in dentigerous cyst, the possible histogenesis of melanocytes in odontogenic lesions is discussed.
M. Khalili , M. Shojaee ,
Volume 19, Issue 3 (4 2006)
Abstract
Background and Aim: Oral lichen planus is a chronic mucocutaneous disease with various clinical expressions. The histopathologic features are not characteristic and may be seen in other diseases. The aim of this study was to determine the clinical and pathologic features of oral lichen planus in oral pathology department of dental school, Tehran university of medical sciences.
Materials and Methods: In this case series study, archive of oral pathology department from 1968 to 2002 was reviewed and cases diagnosed as lichen planus and related lesions selected. The diagnosis of oral lichen planus was confirmed by evaluation of microscopic slides. Clinical informations such as age, sex, site and duration of lesions and differential diagnosis as well as microscopic findings were recorded. Data were analyzed with SPSS software using t student, ANOVA, Chi-square and Post Hoc Tukey tests with p<0.05 as the limit of significance.
Results: From a total of 402 cases recorded as lichen planus and related lesions, 251 cases were confirmed for final analysis. The mean age of patients was 42 years (5 to 83 years). 50.4% of cases were men and 49.6% women. The most prevalent clinical type was the ulcerative form and the mean duration of disease was 18.4 months. Buccal mucosa was most frequently involved followed by the tongue and gingiva. A white patch, Wickham’s striae and mucosal erythema were the most prevalent clinical appearance and parakeratosis , orthokeratosis and eosinophilic band the most frequent microscopic features.
Conclusion: Based on the results of this study, the correlation of clinical and pathological findings in the proper diagnosis of oral lichen planus is emphasized.
M. Ashoori , A. Salimian , N. Jalayer Naderi ,
Volume 19, Issue 4 (6 2007)
Abstract
Background and Aim: Microscopic differentiation between well differentiated squamous cell carcinoma and verrucous carcinoma is very difficult. As these lesions have different clinical course and treatment a reliable method to help distinguish between them is necessary. The basement membrane in oral verrucous carcinoma is generally intact whereas in oral squamous cell carcinoma is mostly discontinuous. This structure can be studied by different methods. The aim of this study was to differentiate these lesions with special staining of basement membrane.
Materials and Methods: In this tests evaluation study, a total of 26 cases consisting of 15 oral squamous cell carcinomas and 11 oral verrucous carcinomas were retrieved from Cancer Institute of Imam Khomeini hospital archive of pathology and their paraffin blocks were cut and stained with Periodic Acid Schiff method. Slides were studied with light microscope to evaluate the continuity of basement membrane. Sensitivity and specificity of this method were calculated.
Results: The sensitivity of this method for differentiating oral squamous cell carcinoma from oral verrucous carcinoma was 100% whereas the specificity was 90.9%. Positive predictive value was 93.75% and negative predictive value 100%.
Conclusion: Based on the results of this study, the sensitivity of this test for diagnosis of oral squamous cell carcinoma was high (100%). Further studies are needed to evaluate the use this method for distinguishing oral verrucous carcinoma from oral squamous cell carcinoma.
H. Razmi , M. Aligholi , Sd. Sadeghi ,
Volume 19, Issue 4 (6 2007)
Abstract
Background and Aim: Many studies have shown that microorganisms are the main cause of pulpal diseases and the main purpose of root canal therapy is their elimination from the root canal system. Antiseptic agents are used to reduce bacteria but their antibacterial activities differ from in vivo to in vitro studies and might be inactivated by dentin and its components in root canal space. This study was designed to investigate the effect of dentin on antibacterial activity of different antimicrobial agents.
Materials and Methods: In this experimental study, two antibacterial agents (sodium hypochlorite and chlorhexidine) with different concentrations were used in four experimental groups: Group 1: dentin, Group 2: demineralized dentin with EDTA, Group 3: dentin matrix and Group 4: dentin mineral component. The species used in this study was Entrococcus faecalis. Different concentration of agents were added to mixture of each experimental group and bacteria. At the baseline and after one and 24 hours, samples were collected and cultured. After incubation period, colonies were counted. Data were analyzed by Tukey test with p<0.05 as the limit of significance.
Results: 2% and 0.2% chlorhexidine, and 5% sodium hypochlorite solutions at the three studied times eliminated Entrococcus faecalis completely. 1% sodium hypochlorite eliminated all bacteria in 1h and 24 hs. Statistical analysis showed significant differences between experimental and control groups (P<0.05). Sodium 1% hypochlorite at time 0, could reduce bacteria significantly (P<0.05) but didn’t eliminate them completely.
Conclusion: Inactivation of intracanal antiseptics was not observed in this study. As elimination of bacteria occurred, application of these antibacterial agents are recommended in endodontic treatment. Further investigations on other antibacterial agents, other concentrations and shorter time intervals are recommended.
M. Khalili , M. Eslami , P. Masoumi ,
Volume 20, Issue 1 (4 2007)
Abstract
Background and Aim: The cell cycle is an important event in tumor growth and differentiation and several molecules are involved in this process. The aim of this study was to evaluate the expression of cyclin D1 (a cell cycle inducer) and p21 (a cell cycle inhibitor) in ameloblastoma of the jaws.
Materials and Methods: In this cross-sectional study, 40 cases of ameloblastoma were selected from the archive of oral pathology department. 3 micron sections were cut from paraffin blocks and immunohistochemically stained with antibody against cyclin D1 and p21waf. Stained cells were counted using an eyepiece graticule and labeling index was calculated. Data were analyzed by SPSS version 11.5 for windows using Mann-Whitney and Wilcoxon signed ranked tests with p<0.05 as the level of significance.
Results: Expression of cyclin D1 protein was detected in nuclei of many tumoral cells. The expression of cyclin D1 in solid and unicystic ameloblastoma and also between its follicular and plexiform variants was not statistically different (P>0.05). There was no statistically significant difference in expression of cyclin D1 between peripheral and central cells (P>0.05). Expression of p21 protein was detected in nuclei of some tumoral cells. There were no statistically significant differences between p21 expression in unicystic and solid ameloblastoma (P>0.05). P21 expression was statistically different between plexiform and follicular variants of ameloblastoma (P=0.049). The difference between p21 expression in peripheral cells of plexiform and follicular variants was statistically significant (P=0.009). This was not observed in central cells. There was no statistically significant relation between p21 and cyclin D1 expression in ameloblastoma (P>0.05).
Conclusion: Based on the results of this study, cyclin D1 expression in ameloblastoma is in high level and it could have an important role in the process of tumorigenesis. P21 expression in ameloblastoma is very faint and its possible effects need further investigation.
Mr. Sharifian , M. Zarrabian , H. Razmi , M. Ghobadi , Mj. Kharrazifard , F. Hemmatzadeh , R Afzalifar ,
Volume 20, Issue 2 (9 2007)
Abstract
Background and Aim: Mineral Trioxide Aggregate (MTA) is a material used in many endodontic problems. Recently a number of studies, have reported that Portland Cement (PC) and MTA have similar physical, chemical and biologic properties. In addition, a material known as Root MTA which is produced in Iran has been claimed to have similar properties to Pro Root MTA. If these claims are true, possible use of PC and Root MTA in clinic instead of Pro Root MTA will be quite cost effective. The aim of this study was to investigate the toxicity of Pro Root MTA, Root MTA and Portland Cement on L929 mouse fibroblasts.
Materials and Methods: In this experimental study 0, 4, 24 hours and 7 days' extracts of materials were transferred to cell culture plates containing L929 fibroblasts. After 24 hours incubation, cells were stained by Neutral Red (NR), and optical density (OD) of each cell was read with ELISA reader. Data were analyzed using Tukey HSD and one way analysis of variance. P<0.05 was considered as the level of significance.
Results: In all surveyed groups and negative control group, at all time points separated cells from the base of the well were round. Refraction which is a characteristic of cellular death was not observed, whereas the separated cells from the base of well in positive control group showed refractional characteristic.
Conclusion: Based on the findings of this study Pro Root MTA, PC and Root MTA have the same biocompatibility. PC seems to have the potential to be used in the same clinical situation as MTA. However in order to replace MTA with these less expensive materials more in vitro and in vivo studies are suggested.
H. Dorriz , R. Afzalifar , B. Afzalifar ,
Volume 20, Issue 3 (4 2007)
Abstract
Background and Aim: As central incisors have a prominent role in esthetics, appropriate preparation, considering natural tooth anatomy and proper planes have always been considered. The aim of this study was to determine the number of planes in labial surface of maxillary central incisors using image processing and mathematical analysis.
Materials and Methods: This pilot study was performed on 32 intact maxillary central incisors in dental students of Tehran university of medical sciences. Photographs were taken from profile view of each tooth by a digital camera. Images were processed and number of planes was obtained using SigmaScan Pro. version 5.00 software and a customized program. Data were analyzed by t-test and regression tests with p<0.05 as the level of significance.
Results: 96.9% of central incisors had three planes and 3.1% had two planes in labial surface. The angle between middle-cervical and middle-incisal planes showed statistically significant difference (p< 0.01).
Conclusion: Based on the results of this study, a few percentage of maxillary central incisors had two planes and most of them had three planes in their labial surfaces. Thus, considering three planes for restoring maxillary central teeth is closer to principles of tooth preparation and esthetics.
P. Alizadeh Oskoee , S. Savadi Oskoee , Z. Borna ,
Volume 20, Issue 3 (4 2007)
Abstract
Background and Aim: Bleaching products as chemical materials can exert side effects on soft and hard tissues and existing restorative materials with oxidizing mechanism. The aim of this study was to evaluate the effect of 15% and 35% carbamide peroxide gels as home and in-office bleaching agents respectively, on microhardness and surface topography of composite resin.
Materials and Methods: In this in vitro study, a total of 75 disc shaped specimens were prepared from Z100 composite resin (3M) and randomly divided into three groups with following treatment designs: group 1, 370C distilled water, group 2, 15% carbamide peroxide, 6 hours/day for 3 weeks, group 3, 35% carbamide peroxide 30 minutes/week for 3 weeks. The microhardness (Vickers hardness) of samples was measured using Shimadzu set on three different points of each sample. 8 samples of each group were selected randomly to be assessed by scanning electron microscopy (SEM) for probable changes in surface topography. Data were analyzed using one way ANOVA and Duncan tests with p<0.05 as the level of significance.
Results: 15% carbamide peroxide group had the maximum amount of microhardness (84.59±1.87) and 35% carbamide peroxide group had the minimum (76. 14±1.77). Only the difference between home bleaching and control group was not statistically significant (P=0.24). The SEM assessing revealed no changes in surface topography.
Conclusion: Based on the results of this study, in-office bleaching may decrease the microhardness of composite resin.
E. Jalalian , S. Banava , S. Erfani ,
Volume 20, Issue 3 (4 2007)
Abstract
Background and Aim: Considering flexural strength of fiber-reinforced composites (FRC) and also the role of conservative cavities in protecting sound tissue of abutments, the aim of this study was to evaluate the fracture resistance of these bridges by handmade samples in vitro.
Materials and Methods: In this experimental in vitro study, 44 sound newly extracted teeth were used to make 22 fixed inlay bridges including 11 three unit anterior upper inlay bridges substituting clinical model of upper central and 11 three unit posterior lower inlay bridges substituting clinical model of lower first molar. Specimens were prepared with FRC and mounted with artificial PDL in acryl. Cases were exposed to final load by using Universal Testing Machine (Instron 1195) with the speed of 1 mm/min. Statistical analysis was performed by Kolmogorov- Smirnov, independent sample T and Kaplan-Meier tests with p<0.05 as the level of significance.
Results: Based on the statistical tests, the 95% confidence interval of mean was 450-562 N in anterior and 1473- 1761 N in posterior area. Fracture strength was high in the studied groups. Fractures in both groups occurred on composite facing, and the framework remained intact. The highest percentage of fracture in posterior teeth was in the middle of pontic towards the distal connector and in the anterior teeth in the lateral connector, between central pontic and lateral abutment. Using the independent sample T test a significant statistical difference was observed between two groups (P<0.001). The fracture resistance of anterior samples was lower than the posterior ones.
Conclusion: Based on the results of this study regarding the high fracture resistance in both areas FRC inlay bridges could be recommended for upper anterior and lower posterior teeth in clinical dentistry certainly more studies are needed to ascertain this treatment option.
H. Siadat, A. Mirfazaelian , M. Alikhasi , M. Mohammad Alizadeh ,
Volume 20, Issue 4 (5 2008)
Abstract
Background and Aim: An important criterion for success assessment of implant-supported prostheses is marginal fit. Vertical and horizontal discrepancy can result in loosening of the prosthetic screw, crestal bone resorption, peri-implantitis and loss of osseointegration. Despite careful attention to waxing, investing, and casting, marginal discrepancies are inevitable. The aim of this study was to evaluate the marginal gap and overhang in three casting methods with two different alloys in ITI implants.
Materials and Methods: In this experimental in vitro study 48 analog abutments were randomly divided into six groups as follows: 1) burn out cap + BegoStar, 2) impression cap + BegoStar, 3) conventional wax up + BegoStar, 4) burn out cap + Verabond2, 5) impression cap + Verabond2, 6) conventional wax up + Verabond2. Waxing was done in 0.7 mm thickness verified by a digital gauge and a putty index was made for all groups. Reamer was used for correction of the finish line after casting in all groups. Castings were seated on analog abutments and embedded in acrylic resin. Specimens were sectioned by isomet instrument and polished and cleaned by ultrasonic cleaner for 10 min. The marginal gap and overextended margins of castings were examined under a Scanning Electron Microscope (SEM) (X200). The mean gap and margin overextension were calculated for each group. Data were analyzed by multivariate analysis and Bonferroni post-hoc test with p<0.05 as the level of significance.
Results: No significant difference in gap size was observed among the three casting methods with two alloys (P=0.056). The marginal gap was not different in the studied casting methods (P=0.092). Gold alloy crowns showed lower marginal gaps compared to base metal alloy crowns (P<0.001). No significant difference in overhang size was observed among casting methods with two alloys (P=0.093). Base metal alloy crowns showed less overhang compared to gold alloy crowns (P<0.001). There was a significant correlation between overhang and use of impression cap in base metal alloys (P<0.001).
Conclusion: Based on the results of this study, vertical discrepancy of frameworks made with gold alloy were less than those made with base metal alloy. Base metal alloy demonstrated less overhang. Conventional wax up or using burn out caps produced less horizontal discrepancy.
P. Deyhimi, M. Nikbakht Dastjerdi, F. Morsali, Sh. Kazemi,
Volume 21, Issue 1 (14 2008)
Abstract
Background and Aim: A single nucleotide polymorphism at codon 72 of the p53 gene alters the p53 protein structure and affects its activity. This polymorphism depends on geographic regions and race. Also its association with some cancers has been reported. The aim of this study was to investigate this polymorphism in well differentiated oral SCC and normal population in the city of Isfahan.
Materials and Methods: In this case-control study, 20 paraffin blocks of non metastatic and well differentiated oral SCC were selected from the archive of oral pathology department of dental school between 2001 and 2005. 20 whole blood samples from normal people were considered as control group. After DNA extraction, p53 codon 72 polymorphism was determined by polymerase chain reaction (PCR) technique using specific primers of Arg and Pro and agarose gel electrophoresis. Data were analyzed by Fisher's exact test with p<0.05 as the level of significance.
Results: The prevalence of Arg/Arg , Arg/Pro and Pro/Pro genotypes in case group were 45%,45% and 10% respectively compared to 45%,50% and 5% in controls. There was no statistical significant difference in p53 codon 72 genotypes distribution between case and control groups.
Conclusion: Based on the results of this study, p53 polymorphism could not be considered as a genetic predisposing factor for oral SCC development in Isfahan.
M. Memarian, Mr. Fazeli, H. Jamalifar, S. Karami,
Volume 21, Issue 1 (14 2008)
Abstract
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.
Ms. Ahmad Akhondi, A. Khorshidian, J. Chalipa,
Volume 21, Issue 2 (12 2008)
Abstract
Background and Aim: Among different treatments of patients with Class III malocclusion , orthopedic protraction of maxilla has been known as an effective method in mixed dentition period. The aim of this study was to evaluate the cephalometric changes of Cl III patients in mixed dentition period following face mask therapy and slow maxillary expansion.
Materials and Methods: This was a before-after study which was conducted on 10 children in mixed dentition period, who had class III malocclusion and maxillary deficiency according to the Stiener and Mc Namara's analysis. The patients were all treated by protraction face mask and slow maxillary expansion. The cephalometric changes of maxilla , mandible and dental relations during the treatment were analyzed by Paired sample T Test. P<0.05 was considered as the level of significant.
Results: The overjet increasement was 1.7mm. Co. ANS distance improvement was 5.6mm, Ptm.ANS distance increasing was 3mm, and ultimately improvement of Gf.s distance was 1.5mm which were all statistically significant (p<0.05).
Conclusion: Based on the results of this study, face mask therapy with slow maxillary expansion is able to improve the horizotal position of maxilla, in patients with Cl III malocclusion , in mixed dentition period.
Sh. Nasermostofi, A. Raghanians, S. Banava, E. Jalalian, A. Abdollah,
Volume 22, Issue 1 (11 2009)
Abstract
Background and Aim: A key factor in restoring the endodontically treated teeth is ferrule preparation. When the ferrule is absent, occlusal loads may cause the post or root to fracture. The purpose of this in vitro study was to evaluate the effect of ferrule preparation on fatigue resistance of teeth restored with quartz-fiber posts.
Materials and Methods: Twenty single-rooted lower premolars having similar dimentions were randomly devided into two groups of 10. In control group the teeth were prepared with 3-mm of remaining coronal tooth structure and in test group teeth were prepared with 1-mm of remaining coronal tooth structure. The teeth were endodontically treated. 9-mm long Post holes were prepared, and D.T. light quartz-fiber(RTD,France) posts were cemented with Panavia F2(Kuraray,Japan).Then the core build up was done with Bisco core build up composite(Bisco,USA) and full metal crowns were cemented with Zinc phosphate(Harvard cement, Germany). All specimens were mounted in acrylic resin blocks and intermittently loaded (180 N) at an angulation of 45- degree to the long axis of the teeth at a frequency of 4 loads per second, until failure occurred.
Results: There was significant difference between the loads cycles of two groups studied. (p<0.0001).
Conclusion: The results of this study showed that an increased amount of coronal dentin significantly increases the fracture resistance of teeth restored with quartz-fiber posts.
M. Sharifian, B. Bolhari, A. Nosrat, M. Aligholi,
Volume 22, Issue 1 (11 2009)
Abstract
Background and Aim: Researches have shown that bacteria play the main role in development of pulpal and periapical diseases. Chemo-mechanical cleaning of infected root-canal system can not remove all of the microorganisms. Thus interappointment medicaments are necessary to aid this goal. Calcium hydroxide is one of the most useful medicaments in root canal therapy, but this medicament can not eliminated all of the bacteria in root canal system. Carvacrol is an edible plant extract that has antimicrobial and anti-inflammatory effects. If this extract is effective against endodontic bacteria, it can be used as an root canal medicament.
Materials and Methods: In this experimental study, Initially, MIC and MBC of carvacrol detected with Macro broth dilution method and determined as 0.3% and 0.6%, respectively. After that, 30 single root and single canal extracted human teeth were used in this study. The number of specimens determined in a pilot study on 4 extracted teeth. After preparation to apical size # 30 with hand and rotary instruments, teeth were randomly divided into two experimental and two control groups. After culturing Enterococcus faecalis in prepared canals, we used emulsion of 0.6% carvacrol and calcium hydroxide in two A and B experimental groups for 7 days as the intracanal medicament. Microbial samples obtained before and after experiment. Then, canals with negative culture selected to obtain dentinal shaving to culture. Data obtained from microbiological samples analyzed with kruskal-wallis and Bonferroni tests.
Results: Results of this study showed that emulsion of 0.6% carvacrol has no significant difference with calcium hydroxide in elimination enterococcus faecalis after 7 days dressing (p>0.05).
Conclusion: Carvacrol can be used as an intrappointment intracanal medicament.
H. Kermanshah, S. Hashemi Kamangar, S. Arami, A. Mirsalehian, M. Kamalinejad, M. Karimi, F. Jabalamoli,
Volume 22, Issue 2 (20 2009)
Abstract
Background and Aim: The microbial cause of dental caries has been proved among its multifactorial etiologies. The prevention and control of dental caries is very critical because of high prevalence and cost especially in high risk patient such as xerostomia. Based on the world attraction to traditional treatment and importance of drug extraction of natural materials and plants, in this in vitro study effect of hydroalcoholic extract of Salvia officinalis and Pimpinella anisum which were very useful in traditional treatment of mouth and teeth disease has been determined against cariogenic bacteria.
Materials and Methods: In this experimental study, hydroalcoholic extracts have been prepared from Salvia officinalis and Pimpinella anisum with maceration method. Their antibacterial activity against Streptococcus mutans, Lactobacillus rhamnosus and Actinomyces viscosus have been evaluated with broth macrodilution method. Data were analyzed with Mann-Whitney test.
Results: Minimum Inhibitory Concentration for Salvia officinalis and Pimpinella anisum for streptococcus mutans were respectively 6.25 and 12.5 µg/ml, for Lactobacillus rhamnosus were 1.56 and 12.5 µg/ml and for Actinomyces viscosus were 12.5 and 50 µg/ml.
Conclusion:Both extracts had growth inhibitory effect on all three bacteria. Salvia officinalis had significantly greater effect on inhibition of growth of all three bacteria. Both extracts had bactericidal effect in the range of concentration.
