فهرست مطالب

Journal of Dental Research, Dental Clinics, Dental Prospects
Volume:9 Issue: 1, Winter 2015

  • تاریخ انتشار: 1394/02/05
  • تعداد عناوین: 12
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  • Maryam Bidar, Neda Eslami, Neda Naghavi, Zohreh Fasihi, Negin Attaran Mashhadi Pages 1-5
    Background And Aims
    Substituting chlorhexidine (CHX) for water has been shown to enhance antimicrobial activity of mineral trioxide aggregate (MTA). The purpose of this study was to compare the compressive strength of MTA mixed with distilled water, 0.12% and 0.2% chlorhexidine.
    Materials And Methods
    MTA was mixed according to manufacturer’s instructions in group I (n = 20). In groups II & III, 0.12% and 0.2% CHX liquid was substituted for water, respectively. Samples were condensed with moderate force into 20 tubes with 1.5 × 5 mm dimensions and were allowed to set for 72 hours at 37°C in 100% humidity. After being removed from the molds, their compressive strength was determined using Instron testing machine. Each group was di-vided into two subgroups according to the time of testing (at 72 hours, and one week). Fractured surfaces of 4 specimens in each group were then evaluated under Scanning Electron Microscope (SEM) to determine their microstructure. One-way ANOVA, Tukey, and paired sample t-test was used for statistical analysis. P < 0.05 was set as significant.
    Results
    There was no significant difference between three groups in terms of their compressive strength after 72 hours. However, the compressive strength of group II was significantly higher than group I (P = 0.034) and group III (P = 0.021) after one week. Crystalline microstructure was similar in all groups.
    Conclusion
    Substitution of 0.012% chlorhexidine for water significantly increased the compressive strength of MTA at 1 week without significant change in crystalline structure.
    Keywords: Chlorhexidine, compressive strength, Mineral Trioxide Aggregate
  • Saeed Rahimi, Saeed Asgary, Mohammad Samiei, Mahmoud Bahari, Seyyed Mahdi Vahid Pakdel, Rasoul Mahmoudi Pages 6-10
    Background And Aims
    Different materials have been used for root-end filling during surgical endodontic treatment. The aim of this in vitro study was to evaluate the dye penetration in different thicknesses of calcium enriched mixture (CEM) cement as root-end filling material.
    Materials And Methods
    Following root canal filling in 70 extracted human single-rooted premolar teeth, the apical 3 mm of their root-ends was resected; the root-end cavities with depths of 1, 2 and 3 mm were prepared by ultrasonic retrotips and filled with CEM cement. After setting of cement, the roots were immersed in 2% Rhodamine B and the dye leakage was measured under stereomicroscope (×16) using Image J software. The data were analyzed by one-way ANOVA and Bonferroni post hoc tests at 5% significance level.
    Results
    The means and standard deviations of dye penetration in the 1, 2, and 3 mm groups were 3395.5 ± 1893.4, 3410.4 ± 1440.5, and 2581.6 ± 1852.9 µm, respectively. The one-way ANOVA analysis indicated significant differences (P < 0.001); however, the Bonferroni post hoc test revealed that only the positive control group differed significantly from the experimental groups (P < 0.001).
    Conclusion
    The findings demonstrated CEM cement to have an adequate root-end sealing ability in 3-mm thickness.
    Keywords: Calcium enriched mixture, CEM cement, Leakage, root, end filling materials, sealing efficacy
  • Nader Abolfazli, Sahar Jabali, Fariba Saleh Saber, Zohreh Babaloo, Adileh Shirmohammadi Pages 11-17
    Background And Aims
    Visfatin, mainly secreted by visceral adipose tissue, especially by macrophages, plays an important role in regulating the defense and immune functions, and functions as a growth factor, a cytokine, an enzyme and more importantly as a proinflammatory mediator. The aim of the present study was to evaluate the effect of non-surgical periodontal treatment on serum and salivary levels of visfatin in patients with generalized moderate-to-severe chronic periodontitis.
    Materials And Methods
    Eighteen patients with generalized moderate-to-severe chronic periodontitis were selected based on periodontal parameters of gingival index (GI), probing pocket depth (PPD), clinical attachment level (CAL) and radiographic parameters. Serum and salivary samples were collected at baseline and one month following non-surgical periodontal therapy (scaling and root planing ([SRP]). Visfatin levels were measured using an ELISA kit. Data were analyzed by SPSS 15, using paired t-test and Pearson’s correlation coefficient.
    Results
    Mean salivary and serum levels of visfatin significantly decreased after non-surgical periodontal treatment (P<0.05). Changes in salivary visfatin levels were more prominent.
    Conclusion
    According to the findings of this study it seems that there is a direct relationship between periodontal tissue inflammation and disease activity with salivary and serum visfatin levels.
    Keywords: Chronic periodontitis, serum, visfatin, nicotineamide phosphoribosyltransferase
  • Shirin Sakhdari, Zohreh Khalilak, Elham Najafi, Rezvaneh Cheraghi Pages 18-22
    Background And Aims
    Early diagnosis of external root resorption is important for accurate treatment. The purpose of this study was to compare the efficacy of a charge-coupled device (CCD) sensor and a photostimulable phosphor (PSP) plate receptor in the diagnosis of artificial external root resorption.
    Materials And Methods
    In this diagnostic in-vitro study, 40 maxillary incisors were mounted in a segment of dry bone and preliminary radiographs were obtained using CCD and PSP sensors. Artificial resorption cavities were produced on the middle-third in half of the samples and on the cervical-third in the other half on the buccal root surfaces. Radiographs were repeated and images were evaluated. Data were statistically analyzed using chi-square and diagnostic tests.
    Results
    There were no significant differences between the two sensors in the sensitivity (P =0.08 and 0.06) and specificity (P =0.13) for the diagnosis of resorption in both root areas. The overall accuracy of CCD was higher than PSP sensor; however, the difference was not statistically significance (P >0.05).
    Conclusion
    CCD and PSP sensors chosen for the present study produced similar results in diagnosing simulated external root resorption.
    Keywords: Dental radiography, digital radiography, root resorption
  • Maryam Amirchaghmaghi, Zahra Delavarian, Mehrdad Iranshahi, Mohammad Taghi Shakeri, Pegah Mosannen Mozafari, Amir Hushang Mohammadpour, Fatemeh Farazi, Milad Iranshahy Pages 23-28
    Background And Aims
    Standard treatment of oral lichen planus (OLP) includes topical or systemic corticosteroids that have many adverse effects. A trend toward alternative natural or herbal drugs has attended recently. This study was conducted to evaluate the effect of quercetin in treatment of erosive-atrophic OLP.
    Materials And Methods
    Thirty patients participated in this randomized clinical trial from April 2010 to June 2010 (Trial Registration Number: NCT01375101). Patients were randomly allocated in two groups. Both groups received the standard treatment (dexamethasone mouthwash and nystatin suspension). Experimental group received oral 250 mg quercetin hydrate capsules (bid) and the control group received placebo capsules. The pain and severity of the lesions were recorded at the initial visit and the follow-ups. All recorded data were analyzed with chi-square, Mann-Whitney, t-test, Wilcoxon and Friedman tests using SPSS 11.5.
    Results
    There were no significant differences between the two groups in severity of the lesions and pain in the follow-ups. According to the Friedman test, there was a significant reduction in pain (P = 0.01) and severity indices (P = 0.00) in the case group. These differences were not observed in the control group (P = 0.26, SI; and P = 0.86, PI). No adverse effect of quercetin was reported.
    Conclusion
    According to the results, no significant therapeutic effect can be considered for quercetin in treatment of OLP.
    Keywords: Clinical trial, lichen planus, quercetin, oral
  • Mitra Askari, Masoud Darabi, Esa Jahanzad, Zahra Mostakhdemian Hosseini, Marjan Musavi Chavoshi, Maryam Darabi Pages 29-34
    Background And Aims
    Various morphologies are seen in different salivary gland tumorsor within an individual tumor, and the lesions show divers biological behaviors. Experimental results support the hypothesis that increased CrkII proto-oncogene is associated with cytokine-induced tumor initiation and progression by altering cell motility signaling pathway. The aim of this study was to assess the CrkII expression in common malignant salivary gland tumors and pleomorphic adenoma.
    Materials And Methods
    Immunohistochemical analysis of CrkII expression was performed on paraffin blocks of 64 carcinomas of salivary glands, 10 pleomorphic adenomas, and 10 normal salivary glands. Biopsies were subjected to immunostaining with EnVision detection system using monoclonal anti-CrkII. Evaluation of immunoreactivity of CrkII was based on the immunoreaction intensity and percentage of stained tumor cells which were scored semi-quantitatively on a scale with four grades 0 to 3. Kruskal-wallis test and additional Mann-Whitney statistical test were used for analysis of CrkII expression levels.
    Results
    Increased expression of CrkII was seen (P=0.005) in malignant tumors including: mucoepidermoid carcinoma, adenoid cystic carcinoma, and carcinoma ex pleomorphic adenoma, but CrkII expression in acinic cell carcinoma was weak. CrkII expression in pleomorphic adenoma was weak or negative. A weak staining was sparsely seen in normal acinar serous cell.
    Conclusion
    Increased expression of CrkII and its higher intensity of staining in tumors with more aggressive biologic behavior in carcinomas of salivary gland is consistent with a role for this proto-oncogene in salivary gland tumorigenesis and cancer progression.
    Keywords: CrkII, immunohistochemistry, salivary gland carcinoma
  • Reza Derafshi, Ahmad Hasan Ahangari, Kianoosh Torabi, Mitra Farzin Pages 35-39
    Background And Aims
    Because of compromised angulations of implants, the abutments are sometimes prepared. The purpose of this study was to investigate the effect of removing one wall of the implant abutment on the retention of cement-retained crowns.
    Materials And Methods
    Four prefabricated abutments were attached to analogues and embedded in acrylic resin blocks. The first abutment was left intact. Axial walls were partially removed from the remaining abutments to produce abutments with three walls. The screw access channel for the first and second abutments were completely filled with composite resin. For the third and fourth abutments, only partial filling was done. Wax-up models were made by CAD/CAM. Ten cast copings were fabricated for each abutment. The copings of fourth abutment had an extension into the screw access channel. Copings were cemented with Temp Bond. The castings were removed from the abutment using an Instron machine, and the peak removal force was recorded. A one-way ANOVA was used to test for a significant difference followed by the pairwise comparisons.
    Results
    The abutments with opened screw access channel had a significantly higher retention than the two other abutments. The abutment with removed wall and no engagement into the hole by the castings exhibited the highest retention.
    Conclusion
    Preserving the opening of screw access channel significantly increases the retention where one of the axial walls of implant abutments for cement-retained restorations is removed during preparation.
    Keywords: Dental abutments, dental implants, dental implant abutment design, implant supported, retention
  • Tahereh Ghaffari, Fahimeh Hamedi, Rad Pages 40-43
    Background And Aims
    Polymethyl methacrylate (PMMA) is widely used for the fabrication of removable prostheses. Silver nano-particles (AgNps) have been added to PMMA because of their antimicrobial properties, but their effect on the mechanical properties of PMMA is unknown. The aim of this study was to investigate the effects of AgNps on the tensile strength of PMMA.
    Materials And Methods
    For this study, 12 specimens were prepared and divided into two groups. Group 1 included PMMA without AgNps and group 2 included PMMA mixed with 5 wt% of AgNps. Tensile strength of the specimens was measured by Zwick Z100 apparatus. Statistical analysis was carried out by SPSS using t-test. Statistical significance was defined at P<0.05.
    Results
    This study showed that the mean tensile strength of PMMA in group 2 was significantly lower than that in group 1. Therefore, the tensile strength decreased significantly after incorporation of silver nano-particles.
    Conclusion
    Within the limitations of this study, tensile strength of acrylic resin specimens was influenced by silver nano-particles.
    Keywords: Acrylic resin, nano, particle, silver, tensile strength
  • Mina Jazaeri, Farzaneh Pakdel, Loghman Rezaei, Soufi, Hamidreza Abdolsamadi, Nasrin Rafieian Pages 44-48
    Background And Aims
    Anticariogenic effects of different mouthrinses have been shown previously. In this in vitro study the anticariogenic effects of polyphenol extract of green tea with 0.05% fluoride, 0.2% chlorhexidine and fluoride-chlorhexidine were compared.
    Materials And Methods
    This in vitro study was performed on 50 maxillary premolars in 5 groups: 1) normal saline; 2) a 10% solution of green tea polyphenol extract; 3) 0.05% fluoride; 4) 0.2% chlorhexidine; and 5) fluoride-chlorhexidine. Each tooth was placed in a tube which contained a cariogenic solution. Every day the teeth were washed (depending on the experimental groups) with 5 mL of mouthrinse solution. The depth of the caries was measured under a polarized light microscope. Data were analyzed using SPSS 13.0 with Kolmogorov–Smirnov, one-way ANOVA and Tukey tests.
    Results
    The mean and standard deviation (in m) of caries depth were 194±16.43, 175±17.94, 142±9.34, 155±13.27, and 144±8.57 in groups 1 to 5, respectively, with significant differences between the groups (P<0.001). Tukey test showed that although there was no significant difference in the depth of caries in groups 1 and 2 (P>0.001), they were significantly less than those in groups 3 to 5 (P<0.001). There was no significant difference between decay depth of groups 3, 4 and 5 (P>0.001).
    Conclusion
    The anticariogenic effect of fluoride-chlorhexidine was the highest among the groups. Although green tea showed higher cariostatic effects than normal saline, in comparison with other mouthrinses, it is less effective. More research is strongly recommended for clinical use of green tea as an anticariogenic agent.
    Keywords: Cariostatic agent, dental caries, mouthwash, polyphenols, green tea
  • Fatemeh Sadat Sajadi, Mohammad Moradi, Abbas Pardakhty, Razieh Yazdizadeh, Faezeh Madani Pages 49-52
    Background And Aims
    Streptococcus mutans is the main pathogenic agent involved in dental caries, and may be eliminated using mouthwashes. The objective of this study was to compare the effects of fluoride, chlorhexidine, and fluoride-chlorhexidine mouthwashes on salivary S. mutans count after two weeks of use and determine the prevalence of their side effects on the oral mucosa.
    Materials And Methods
    In this clinical trial, 120 12-14 year-old students were selected and divided into three groups. Each group was given one of fluoride, chlorhexidine, or fluoride-chlorhexidine mouthwashes. They were asked to use it twice a day for two weeks. Salivary samples were collected at baseline and after two weeks. Data were analyzed by Wilcoxon and Kruskal-Wallis tests.
    Results
    In all the study groups, there were statistically significant reductions in salivary S. mutans counts two weeks after using the mouthwashes (P < 0.05). In addition, fluoride-chlorhexidine mouthwash had a significant effect on the reduction of S. mutans count in comparison with fluoride alone. The prevalence of oral side effects in fluoride-chlorhexidine mouthwash was more than 90%.
    Conclusion
    Adding fluoride to chlorhexidine mouthwash can significantly decrease salivary S. mutans count after two weeks. Fluoride-chlorhexidine has the highest rate of oral side effects between the evaluated mouthwash compounds.
    Keywords: Chlorhexidine, fluoride, Streptococcus mutans
  • Saeed Nezafati, Leila Ashkhasi, Mohammadali Ghavimi Pages 53-56
    Condylar dislocation is not an uncommon condition and occurs when the condyles are displaced anterior to the articular eminence and are unable to reduce back into the glenoid fossa. Long-standing dislocations are difficult to treat with the conservative methods and usually need surgical intervention. In this paper, a long-standing dislocation treated by bilateral extra-oral ramus osteotomy is described and the literature is reviewed.
    Keywords: Dislocation, mandibular condyle, osteotomy
  • Root canal treatment of a hypertaurodont mandibular second molar: a case report
    Davood Jamshidi, Alireza Adl, Fereshte Sobhnamayan, Mehrdad Bolurian Pages 57-59
    Taurodontism is a morphologic feature of generally multi-rooted teeth with large pulp chambers and shortened roots. A case of endodontic treatment in a 24-year-old male with the chief complaint of swelling and pain in the right mandibular region is described. Periapical lesion was present in the radiographic examination of hypertaurodont second mandibular molar. Four root canals were detected with an endodontic microscope. The canals were prepared and obturated with lateral condensation technique in the second appointment. The patient was asymptomatic in the 18-month follow-up.
    Keywords: Pulp chamber, root canal, taurodontism