Vol 12, No 11 (2015)

Original Article

  • XML | PDF | downloads: 325 | views: 484 | pages: 789-796

    Objectives: Lichen planus (LP) is a chronic inflammatory mucocutaneous disease. Its treatment is often symptomatic and includes topical and systemic corticosteroids. Although corticosteroid therapy is usually successful, it has side effects and thus, an alternative treatment is favorable. The aim of this study was to compare the efficacy of topical curcumin and triamcinolone for treatment of oral lichen planus (OLP). 

    Materials and Methods: In this study, 50 patients (36 women and 14 men) in the age range of 38 to 73 years with OLP were randomly divided into two groups. Each group received 0.1% triamcinolone or 5% curcumin oral paste three times a day for four weeks. Assessment of the appearance score and severity of pain was done at baseline and at the end of two and four weeks and recorded in the patients’ questionnaires. The data were analyzed by SPSS 17 software, using the Mann-Whitney and Spearman’s tests.

    Results: With respect to pain reduction, nine patients (36%) in the curcumin group and eight patients (32%) in the triamcinolone group showed complete remission. With respect to the appearance score, one patient (4%) in each group showed complete remission. No statistically significant difference was noted between the two groups.

    Conclusion: Application of curcumin is suggested for treatment of OLP because of its desirable anti-inflammatory effects and insignificant side effects.

  • XML | PDF | downloads: 248 | views: 371 | pages: 797-806

    Objectives: The optimal goal of radiography is to provide high-quality diagnostic images with the least patient radiation dose. The aim of this study was to evaluate the accuracy of cone-beam computed tomography (CBCT) and intraoral photostimulable phosphor plate (PSP) digital and film-based conventional radiography for detection of artificial cancellous bone defects.

    Materials and Methods: Five dry human mandibles were used in this study. The mandibles were placed inside a water bath made of plexiglass plates; then PSP and CBCT scans were obtained. The mandibles were cut by a coping saw in buccolingual dimension and oval defects measuring 6.1×6.1 mm, 3×6.1 mm and 4×4 mm were created by a milling machine in the spongy bone. After fixing the two parts together (buccal and lingual), radiographs were repeated. Presence or absence of defects on images was evaluated and recorded by the two observers. Using SPSS 16, compatibility level, sensitivity, specificity and receiver operating curve (ROC) analysis were determined for each observer.

    Results: The intraobserver agreement in all three imaging modalities was low to moderate (kappa≤0.613). The inter-observer agreement in all the three imaging modalities was moderate (kappa=0.406). The area under the curve (AUC) of the imaging modalities in each observation was not significantly different. The area under the curve based on defect size for the two observers was not significantly different either.

    Conclusion: Defects confined to spongy bone can be identified on film and PSP radiographs and CBCT scans. However, interpretation of PSP images and CBCT scans needs greater expertise and skills.

  • XML | PDF | downloads: 217 | views: 369 | pages: 807-814

    Objectives: The aim of this in-vitro experimental study was to assess the effect of application of a desensitizing varnish on the enamel and dentin marginal seal.

    Materials and Methods: Seventy-two freshly extracted, intact human premolar teeth were divided into four groups (n=18). Class V cavities (3mm in length, 2mm in width and 2mm in depth) were prepared on the buccal surface of each tooth. The following sealing materials were applied in the four groups: One-step Clearfil S3 Bond (S3) self-etch adhesive, two-step Clearfil SE Bond (SE) self-etch adhesive, S3 Bond+ VivaSens desensitizing varnish (VS+S3) and Clearfil SE Bond + VivaSens (VS+SE). The cavities on the teeth were then incrementally filled with Z350 light-cure composite. The teeth were stored in distilled water for 24 hours at 37°C, and were then thermocycled for 1000 cycles. Then, all the specimens were prepared for dye penetration test and were immersed in 2% basic fuchsin dye and incubated at 37°C for 24 hours. The teeth were then sectioned buccolingually along the center of restorations with a diamond disk.   Microleakage at the tooth-restoration interface was assessed in the enamel and dentin margins blindly using dye penetration under a stereomicroscope at ×20 magnification.

    Results: There was significantly greater leakage at the enamel and dentin margins in group VS+SE than in group SE; also, these values were higher in group VS+S3 than in S3.

    Conclusion: Combined application of desensitizing varnish and self-etch adhesives seems to increase microleakage in composite restorations. Thus, its application is not suggested.

  • XML | PDF | downloads: 319 | views: 372 | pages: 815-822

    Objectives: Marginal adaptation is important for long-term success of full-coverage restorations. The aim of this study was to determine the effect of porcelain firing cycle and different thicknesses of IPS e.max core on marginal accuracy of all-ceramic restorations.

    Materials and Methods: A standard stainless steel die with 0.8 mm classic chamfer finish line and 10° taper was used in this in vitro study. An impression was taken from the stainless steel die to fabricate 20 epoxy resin dies, which were then scanned and IPS e.max CAD cores were fabricated using computer-aided design/computer-aided manufacturing (CAD/CAM) technique in two groups of 10 with  0.7 mm (group A) and 0.4mm (group B) core thickness. Copings were then placed on their respective dies and randomly numbered. The amount of marginal gap was measured in 10 points under a stereomicroscope (×90 magnification) before and after porcelain veneering.

    Results: The mean gap in 0.7mm and 0.4mm core thicknesses was 15.62±2.55µm and 19.68±3.09µm before porcelain firing and 32.01±3.19µm and 35.24±3.8µm after porcelain firing. The difference in marginal gap between the two thicknesses was significant before porcelain firing but not significant after veneering. Significant differences were also found in the marginal gap before and after porcelain veneering in each group.

    Conclusion: The porcelain firing cycle increases marginal gap in IPS e.max CAD restorations; 0.3 mm decrease in core thickness slightly increased marginal discrepancy, however it was not significant.

  • XML | PDF | downloads: 281 | views: 412 | pages: 823-834

    Objectives: The aim of this study was to histologically compare the regenerative properties of two allografts manufactured by two Iranian companies.

    Materials and Methods: In this study, four 8-mm defects were produced in the calvaria of 12 rabbits. In three defects, three types of allografts namely ITB, CenoBone and Grafton were placed and one defect served as control. Samples were prepared and histomorphometric evaluations were carried out after healing periods of four weeks (interval 1) and eight weeks (interval 2). Qualitative and quantities variables were compared and analyzed with SPSS software.

    Results: Mild inflammation was observed in 45% and 12.5% of the samples in the first and second intervals, respectively. Foreign body reaction was observed in only 5% of the samples. The quality of regenerated bone was immature, mixed and lamellar in 54.5%, 15.9% and 4.5% of the samples, respectively. The rate of allograft resorption was the highest and lowest in the CenoBone and Grafton samples, respectively. The mean amount of regenerated bone was higher in areas containing Grafton; however, the differences were not statistically significant.

    Conclusion: Despite the differences in the numerical values of bone regeneration, there were no statistically significant differences in bone generation among the material groups, and allografts manufactured in Iran can be suitable alternatives to Grafton with the same good properties. Further studies are necessary to clarify the efficacy of these allografts.

  • XML | PDF | downloads: 246 | views: 391 | pages: 835-840

    Objectives: Regarding the implication of viruses particularly herpes in pemphigus vulgaris, we sought to assess and compare the level of immunoglobulin G (IgG) antibodies against herpes simplex virus types 1 and 2 (HSV1 and HSV2), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) in patients with pemphigus vulgaris and healthy people.    

    Materials and Methods: In this cross-sectional study, 25 patients with pemphigus vulgaris and 27 healthy individuals comprised the experimental and control groups, respectively. Serum samples were taken from both groups; the levels of IgG antibodies against HSV1, HSV2, CMV and EBV were measured using ELISA.  

    Results: Immunoglobulin G titer was higher for all four viruses in the patient group in comparison to the control group. This difference was significant for anti-EBV (P= 0.005), anti-CMV (P=0.0001) and anti-HSV2 (P=0.001) but not significant for anti-HSV1 (P= 0.36).

    Conclusion: Viruses including EBV, CMV, and HSV2 probably play a role in the pathogenesis of pemphigus in addition to the effects of genetics, toxins and other predisposing factors. In this study, no statistically significant relationship was observed between HSV1 and pemphigus vulgaris, which was probably due to the high titer of anti-HSV1 IgG in healthy individuals in the community. More studies must be done in this regard.

  • XML | PDF | downloads: 238 | views: 364 | pages: 841-845

    Objectives: The aim of this study was to compare apical sealing ability of alpha and beta phases of gutta-percha by means of bacterial leakage model.

    Materials and Methods: Fifty single-rooted human premolars were selected. The root canals were prepared with Mtwo rotary instruments up to apical #35.04. Forty teeth were randomly divided into two groups (n= 20). The root canals were obturated by alpha phase (G1) and beta phase (G2) of gutta-percha and AH26 sealer, respectively, with warm vertical compaction technique. Ten teeth served as positive (n=8) and negative (n=2) control groups. Then, the specimens were sterilized with ethylene oxide gas. Bacterial suspension of Enterococcus faecalis (E. faecalis) in 0.5 McFarland concentration was prepared. All teeth were mounted in plastic vial caps containing Muller Hinton broth and then exposed to bacterial suspension of E. faecalis every three days up to 31 days. The number of days required for the contamination of the entire root canals was recorded. The data were analyzed using Mann Whitney U test.

    Results: There were no significant differences in bacterial leakage between the G1 and G2 groups (P>0.05). Negative controls revealed no microbial leakage; whereas positive controls showed gross microbial leakage.

    Conclusion: Despite better thermal conduction and adaptability of alpha phase of gutta-percha, our study revealed no significant difference in bacterial leakage between alpha and beta phases of gutta-percha in warm vertical compaction.

  • XML | PDF | downloads: 230 | views: 391 | pages: 846-852

    Objectives: Squamous cell carcinoma (SCC) is the most common malignant neoplasm of the oral cavity and a public health threat. Tumor progression is believed to be influenced by angiogenesis as well as tumor cell proliferation; however, the correlation of these two factors in tongue SCC still remains unclear. This study aimed to assess the correlation of these two factors in tongue SCC.

    Materials and Methods: Twenty-four paraffin block sections of tongue SCC were stained with monoclonal antibodies against CD105 and Ki-67. In order to assess the expressions of CD105 and Ki-67 to evaluate CD105 microvessel density (MVD), positively stained microvessels were counted in a predominantly vascular area (hot spot) in each specimen at ×400 magnification. The proliferation index was expressed as a percentage of Ki-67 positive cells. Data were analyzed by t-test and Pearson’s correlation coefficient (P<0.05).

    Results: The CD105 MVD was related to histological grading as well as Ki67 labeling index (LI; P= 0.045 and P=0.047, respectively). Both CD105 MVD and KI67 LI were unrelated to sex (P=0.41 and P=0.78, respectively) and age (P=0.20 and P=0.36, respectively) of the patients. No correlation was found between CD105 MVD and Ki67 LI (P=0.86).

    Conclusion: The mean CD105 MVD was significantly lower in poorly differentiated tumors. This finding suggests that CD105 MVD may serve as a valuable prognostic factor in tongue SCC. Absence of correlation between MVD and tumor cell proliferation indicates that these processes may be guided by unrelated mechanisms.

  • XML | PDF | downloads: 225 | views: 385 | pages: 853-858

    Objectives: Optimum viewing conditions facilitate identification of radiographic details and decrease the need for retakes, patients’ costs and radiation dose. This study sought to evaluate the effects of different viewing conditions on radiographic interpretation.

    Materials and Methods: This diagnostic study was performed by evaluating radiograph of a 7mm-thick aluminum block, in which 10 holes with 2mm diameters were randomly drilled with depths ranging from 0.05 mm to 0.50mm. The radiograph was viewed by four oral radiologists independently under four viewing conditions, including a white light viewing light box in a lit room, yellow light viewing light box in a lit room, white light viewing light box in a dark room and yellow light viewing light box in a dark room. Number of circular shadows observed on the film was recorded. The data were analyzed by two-way ANOVA.

    Results: The mean number of detected circular shadows was 6.75, 7.5, 7.25 and 7.75 in white light viewing light box in a lit room, white light viewing light box in a dark room, yellow light viewing light box in a lit room and yellow light viewing light box in a dark room, respectively. Although the surrounding illumination had statistically significant effect on the radiographic details (P≤0.03), the light color of the viewing light box had no significant effect on visibility of the radiographic details.

    Conclusion: White and yellow light of the viewing light box had no significant effect on visibility of the radiographic details but more information was obtained in a dark room.

  • XML | PDF | downloads: 298 | views: 387 | pages: 859-867

    Objectives: This experimental study evaluated the effect of bonding application time on the microshear bond strength of composite resin to different types of glass ionomer cements (GICs).

    Materials and Methods: One-hundred and sixty specimens (two conventional and two resin-modified GICs) were prepared and divided into 16 groups. The surface of all specimens was prepared using two different bonding systems (Frog and Stea) at three different times. After setting, the composite resin (Z100) was placed over the GICs. The specimens were then stored in distilled water for 24 hours (37oC) and exposed to microshear stresses at a crosshead speed of 1 mm/min. The results were analyzed using three-way ANOVA and Tukey’s test (P˂0.05).

    Results: In conventional GICs, bond strength was affected by the type of bonding system at different times, and bond strength was significantly higher in the Fuji II group compared to Riva Self Cure group. In the Riva Self Cure group, bond strength was significantly affected by time; whereas, the type of bonding system failed to exert a significant effect on bond strength. There was no significant correlation between the type of bonding system and the two brands of resin-modified GICs. Bond strength was not affected by the type of bonding agent; however, among the two brands of resin-modified GICs, Fuji II LC yielded a significantly stronger bond.

    Conclusion: It appears that the type of bonding agent does not affect the microshear bond strength, and the bonding application time affects the microshear bond strength in Riva Self Cure GICs.