Journal of Mashhad Dental School
Year:2018 | Volume:42 | Issue:3 |Papers Count:13

Introduction: Oral mucositis is one of the common side effects in patients under chemotherapy, which can cause pain, discomfort, and infection. This study aimed to compare the effect of topical honey and chamomile on preventing chemotherapyinduced mucositis in children with leukemia. Materials and Methods: This single-blinded, randomized clinical trial was performed on 40 patients who aged 1-14 years and were under chemotherapy. The patients were assigned into four groups of positive control (chlorhexidine mouthwash), negative control (normal saline), intervention one (honey mouthwash), and intervention two (MC). All the groups were matched regarding the number, age, and gender of the participants. In each group, sterile gauzes dipped in the desired mouthwash were rubbed on the mucosal surface of cheek, palate, and tongue. During the first, seventh, and fourteenth day’ s post-chemotherapy the oral cavities of children were examined in terms of oral mucositis according to the criteria issued by the World Health Organization. All the data were analyzed by Kruskal-Wallis and Mann-Whitney tests using SPSS. P<0. 05 was considered as significant for all the tests. Results: The findings demonstrated that no developed on the first day of examination in patients of all the groups. On the seventh day, mucositis was not observed except in the normal saline group (30% mild, 30% moderate). Moreover, mucusitis did not develop even on the fourteenth day except in the normal saline group (100% mild). Conclusion: According to the results of the present study, topical application of honey might be effective in preventing chemotherapy-induced mucositis in children with leukemia.

Introduction: The purpose of this study was to evaluate the association of maxillary sinus volume and pneumatization of the alveolar bone with age and gender. Materials and Methods: This cross-sectional study was conducted on the computed tomography (CT) images of the healthy maxillary sinuses obtained from 199 adult patients. The sinus pneumatization of the alveolar bone was measured in each of the posterior teeth by means of the coronal CT images. The measurement of the three-dimensional sinus volume was accomplished using the Amira software. The data were analyzed through the Spearman correlation coefficient and regression analysis. Results: Out of the 199 patients, 159 and 40 cases were male and female with the age ranges of 18-92 and 18-68 years, respectively. The mean maxillary sinus volumes were 15. 32± 5. 80 and 13. 02± 4. 91 ml in the males and females, respectively, which were significantly different between the two genders in both left and right sinuses. In this regard, the independent t-test showed that the mean volumes of the right and left maxillary sinuses in men were greater than those in women (P=0. 001 and P=0. 008, respectively). There was a significant relationship between age and maxillary sinus volume (r<-0. 15, P=0. 03), indicating that the sinus volume decreases with aging. A high correlation was obtained between the volume of the maxillary sinus and alveolar bone pneumatization (r=0. 58 for the right sinus and r=0. 72 for the left sinus). T-test showed that the pneumatization was greater in men than that in women; however, it was not significant. Additionally, the Spearman correlation test showed no correlation between age and alveolar bone pneumatization. Conclusions: The findings of this study showed that maxillary sinus volume was higher in men than that in women, and that this volume decreased with aging. Furthermore, the mean of alveolar bone pneumatization was not correlated with age and showed no significant difference between the two genders.

Introduction: This study was performed to investigate the distribution of stress in indirect resin restorations of class II MOD cavities for obtaining the optimum wall angle and also the effect of axiopulpal angle bevel using 3D finite element analysis (FEA). Material & Methods: A three-dimensional model of normal mandibular first molar and three class II cavity models with different wall angles were created. Also, all models were examined with axiopulpal angle bevel. The vertical occlusal force of 100 N was applied. The characteristics of all materials were defined as isotropic and elastic and, with the aid of a linear analysis; the distribution of stress and the maximum stress created in each model were obtained in mega-Pascal scale. T test was used for statistical of data. Results: The maximum stress in the simulated normal tooth was 24. 63 MPa. Distribution of stress indicates the accumulation of pressure in the center and the furcal region of the first molar, as well as the cusps in the occlusal region. In beveled model of 95-degree angle, maximum stress was 24. 90 MPa with a decrease of 0. 05 maximum stress compared to the non-beveled model. In the cutting angle of 97. 5, the maximum stress was 24. 85 in the no-bevel model to the maximum stress of 24. 80 in the model compared with axiopulpal angle bevel, which showed achieved a decrease of 0. 05 in the maximum stress. At the cutting angle of 100, the maximum stress of 25. 30 was in the no-beveled model comparing to maximum stress of 25. 20 in the model with axiopulpal angle bevel, which showed red action of MPA. Conclusion: Considering the limitations of such software studies, it seems that according to the results, the best treatment result is at angle of 97. 5. Axiopulpal angle bevel reduces the maximum stress in the restoration and reduces the chance of failure.

Introduction: The present study was conducted with the aim of evaluating the effects of Er: YAG laser (λ =2940 nm) and acidulated phosphate fluoride (APF) gel on the acid resistance of enamel white spot lesions, when applied alone or combined together. Materials and Methods: This laboratory study was conducted on 90 buccal and lingual slabs of human molar teeth. The samples were submitted to pH-cycling model to create white spot lesions. Subsequently, they were randomly assigned into six groups of positive control (without enamel white spot lesion), negative control (with enamel white spot lesion), enamel treated with APF gel, enamel irradiated with Er: YAG laser, pre-treated with APF gel followed by Er: YAG laser irradiation, and pre-irradiated with Er: YAG followed by APF gel application. Before and after the treatments, the samples were analyzed using potentiometer in order to evaluate the fluoride contents. Statistical analysis was performed using Kruskal-Wallis and ANOVA tests (P=0. 05). Results: According to the results, the application of APF gel before or after laser irradiation resulted in the highest enamel resistance to acid and fluoride uptake (P<0. 05). The group received laser irradiation showed an increase in enamel fluoride uptake as compared to the positive and negative control groups. However, the groups submitted to laser had no significant difference with those administered APF gel in this regard. Conclusion: As the findings indicated, Er: YAG laser changes the chemical combination of the enamel, and improves enamel hardness, especially when combined with topical fluoride, suggesting its anticaries potential.

Background and Objectives: Peripheral and central giant-cell granulomas (PGCGs and CGCGs) and giant-cell tumor (GCT) of bone have similar histopathological features with different biological behavior. The aim of this study was to evaluate the expression of transforming growth factor beta (TGF-β ) in these lesions by the help of immunohistochemistry. Materials and Methods: In this study, 15 PGCGs, 15 CGCGs, and 10 GCTs were evaluated. The TGF-β immunoreactivity was assessed in mononuclear cells (MC) and multinucleated giant cells (MGC) of the studied groups. Data analysis was performed using Kruskal-Wallis and Dunn’ s tests. Results: There was a significant difference between three studied groups regarding both MCs and MGCs. The highest mean of TGF-β immunostaining was observed in GCTs and the lowest in PGCGs. In pairwise comparison of the studied groups, a significant difference was observed between PGCGs and GCTs considering both MCs and MGCs. Additionally, a significant deference was reported only in MCs between CGCGs and GCTs. Conclusion: The results may explain the different biological behavior and pathogenesis of these lesions despite the similarity of histopathologic features.

Introduction: Composite veneers are used as a conservative and cosmetic treatment for discolored and deformed teeth or defective restorations. Due to the effect of various exposure methods on polymerization shrinkage stress, this study aimed to investigate the effect of various treatment techniques on shear bond strength of composite veneers restoration. Materials and Methods: In this in-vitro study, 72 premolar teeth were divided equally into enamel and dentin groups. The buccal surfaces in each groups were abraded to reach flat enamel or dentin surfaces. The specimens were mounted in acrylic cubs and bonding procedures were performed using Single Bond 2. The specimens were divided into three subgroups according to the methods of exposure including conventional, soft-start, and pulsedelay techniques. In each subgroup, a composite cylinder was formed on buccal surfaces using Z250 composite and different curing modes. The shear strengths were measured and the data were analyzed using one-way analysis of variance followed by Tukey multiple comparisons test (α =0. 05). Results: There was no significant difference in shear strength of composite to enamel between enamel subgroups (P=0. 185). However, the difference in shear strength of composite to dentin between dentin subgroups was significant (P=0. 042). Adhesive failures were the most among all subgroups. Conclusion: Curing with soft-start and pulse-delay methods can increase shear strength in both enamel and dentin surfaces. Nevertheless, it is more effective in dentin surfaces.

Introduction: In this study, we evaluated the changes in smile morphometric indices before and after fixed orthodontic treatment with and without tooth extraction. Materials and Methods: This retrospective study was performed using photographs of 46 female patients (aged between 18 and 25 years) that were taken before and after fixed orthodontic treatment. In 26 patients (Ext), the first premolars were extracted for orthodontic purposes, and in 20 patients (Nonext), no tooth was extracted for orthodontic treatment. The photographs were analysed with smile analyzer software and morphometric smile parameters were measured. In order to compare the indicators before and after treatment, paired t-test was used. For comparing the Ext and Nonext groups, we used independent t-test. Results: We did not find any significant changes in smile morphometric indices before and after orthodontic treatment in neither group (P=0. 05). The two groups (with or without extraction) were compared using smile analyzer software, which showed that in the pre-treatment photographs, visible maxillary dentition width (P=0. 01, and in post-treatment photographs, visible maxillary dentition width (P=0. 00), smile width (P=0. 04), and smile height (P=0. 04) differed significantly between the extraction and Nonext groups. Conclusion: Orthodontic treatment with Roth system in both groups of with or without tooth extraction does not cause any significant changes in smile morphometric indices.

Introduction: Oral Squamous Cell Carcinoma (OSCC) is one of the most prevalent cancers of oral cavity worldwide. The main components consisting basal lamina are collagen type IV and adhesive glycoprotein lamina. Local loss of basement membrane leads to formation of laminin-5, gamma-2 (laminin– 5γ 2) through proteolysis of basement membrane or synthesis in cytoplasm of neoplastic cells. Laminin– 5γ 2 is a protein that plays a central role in migration of the neoplastic cells during tumor invasion. Expression of this protein in cells and stroma adjacent to tumor can confirm the cellular invasion. The aim of this study was to evaluate expression of laminin– 5γ 2 in OSCC, verrucous carcinoma (VC), and dysplastic mucosa (DM), compared to normal mucosa (NM). Materials and Methods: 57, 31, 9, 9, and 8 paraffin blocks of squamous cell, OSCC, VC, DM, and NM (as control group) were scored as laminin-5γ 2 markers, respectively. The 10 and 40-fold magnifications were used to determine the percentage of colored cells. All the data were statistically analyzed by Chi-square and Mann-Whitney tests using SPSS version 20. Results: the findings demonstrated that expression of laminin marker was positive in the epithelium of 61. 3, 33. 3, and 22. 2% of the SCC, VC, and DM samples, respectively. On the other hand, it was negative in 100% of the NM samples. The distribution frequency of negative and positive laminin samples was assessed based on the type of lesions. The significance level was considered as 0. 006, which is less than 0. 05. There was a significant difference concerning the number of laminin positive lesions between the types of oral malignancies and normal mucosa. The SCC lesions revealed the highest positive results. Conclusion: According to the results of this study, laminin– 5γ 2 expression in the basement membrane, extracellular matrix, and epithelium of malignant tumor tissue might indicate the invasive and metastatic behavior of the OSCC.

Introduction: Suitable fracture resistance is a main factor for long term success in restoration treatment. The purpose of this study was to evaluate the fracture resistance of Class II restoration with total-etch and self-etch adhesives along with various bulk-fill composites. Materials and Methods: In this in-vitro study, conventional class II cavities were prepared on the proximal surface of 40 sound human premolar teeth with almost same size and shape. Half of the cavities were restored with Sonic Fill nanohybrid bulk-fill composite with total-etch (Optibond Solo Plus, Kerr) and self-etch (Optibond XTR, Kerr) adhesives, and the other half were restored with Tetric N-Ceram, (Ivoclar vivadent) bulk fill composite with total-etch and self-etch adhesives. For fracture resistance evaluation, the specimens were put in Instron device. The amount of force was recorded at the moment of fracture for the evaluation of experimental groups. The data were analyzed by bivariate ANOVA. Results: The highest and lowest fracture resistance were observed in Tetric N-cream with total-etch adhesive and self-etch adhesive, respectively. There was no significant difference in fracture resistance between Tetric N-Ceram and Sonic fill with totaletch and self-etch adhesives (P>0. 05). Conclusion: Both of the bulk-fill composites with various adhesives had the same fracture resistance.

Introduction: Oral infections caused by Candida species are increasing widely. Nystatin is one of common topical medications used in the treatment of these oral lesions, which shows anti-fungal and antimicrobial activities. Common anti-fungal drugs show various side effects and result in drug resistance, as well as frequent recurrence. Thus, trying to find an alternative for synthetic drugs that do not have these disadvantages is valuable. This in-vitro study was aimed at comparing antifungal effects of Organum vulgare extract with nystatin on Candida albicans. Materials and Methods: In this in-vitro study, aqueous and alcoholic extracts of Origanum vulgare were prepared in concentrations of 10, 20, 40, 80 and 100%. Candida albicans was cultured on Sabouraud Dextrose Agar. Within each plate, one disc containing any of the concentrations using plant extracts, a nystatin disc as positive control, and a disk containing distilled water as negative control were placed. After 24 h, the mean diameter of non-growth halo of different concentrations and nystatin were compared using One-way ANOVA or independent two samples t-test. Results: The mean diameter of non-growth halo around the discs containing aqueous and alcoholic extracts of Organum vulgare were significantly lower than that of nystatin in all the concentrations (P<0. 001). Conclusion: Antifungal effect of nystatin on Candida albicans was more than that of aqueous and alcoholic extracts of Organum vulgare.