Journal of dentistry (Shiraz, Iran)最新文献

Statement of the problem: Determining the prevalence of respiratory viruses' coinfection with coronavirus disease 2019 (COVID-19) is essential to defining its true clinical influence.

Purpose: This study aimed to evaluate co-infection rates between severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2) and respiratory syncytial virus (RSV) in infected patients in Shiraz, south of Iran.

Materials and method: In a cross-sectional descriptive study, oropharyngeal, nasopharyngeal aspirate (NPA), and saliva samples of 50 COVID-19 patients who were referred to Ali-Asghar hospital (Shiraz, Iran) from March to August 2020, were collected. A control group consisted of age and sex-matched healthy participants. The nasopharyngeal and oropharyngeal aspirates were collected by sterile swabs. All cases were hospitalized, and all SARS-CoV-2 patients had a fever and respiratory symptoms. The samples were packed in a vial with 1 mL of transport medium and transported to the Valfagre specialty laboratory, where they were tested for RSV using a real-time polymerase chain reaction (PCR).

Results: 100 nasopharyngeal/oropharyngeal aspirates and saliva samples including 50 healthy controls (24 females, 26 males) and 50 COVID-19 patients' samples (27 males and 23 females) were studied. There was no significant difference regarding age as well as gender between both groups (p> 0.05). None of the healthy subjects was infected with RSV; however, 5(10%) patients from COVID-19 group were infected with the RSV virus. Chi-square test did not show a significant difference between RSV infection in COVID-19 patients and healthy subjects.

Conclusion: The outcome of present research showed that concurrent RSV with COVID 19 infection might be seen in hospitalized patients in Shiraz Southwest of Iran. For more reliable findings, further research on bigger populations, including more pathogens in several places around the country, and considering the severity of symptoms is required.

Statement of the problem: Due to the unfavorable properties of eugenol, the eugenol content can be reduced to improve the properties of zinc oxide eugenol (ZOE) by making a new combination of nanocurcumin called curcumin pulpal paste (CPP).

Purpose: The aim of this in vitro study was to evaluate the solubility and tooth discoloration of three concentrations of CPP compared to ZOE, and Metapex.

Materials and method: In this in vitro study for evaluating of the solubility, five groups including ZOE, Metapex, and three concentrations of CPP (5%, 10%, and 20%) were tested. For evaluating the solubility, the changes in of the weight of samples were measured at 1, 3, 7 and 30 days after initial setting. In order to evaluate the tooth discoloration, 75 bovine maxillary anterior teeth were filled with one of five pulpal pastes. The changes in tooth color were evaluated at 1 hour, 1 week, 1 and 3 months after material placement.

Results: The solubility increased by increasing the nano-curcumin percentage in CPPs. After 30 days, the solubility of the 5%CPP, and ZOE was not significantly different (p= 1.000). According to the colorimetric test, after 3 months, the highest discoloration was recorded for 20% CPP (8.45), and the smallest discoloration was registered for Metapex (4.06). The discoloration of 5% CPP, and 10% CPP was similar to ZOE's color change (p> 0.05).

Conclusion: The results of the present study showed that the solubility of pulpal paste has increased with increasing curcumin concentrations. Therefore, pulpal paste with different nanocurcumin concentrations can be used considering the patient's age and the desired time of deciduous tooth loss, and dissolution of pulpal paste. Concerning the discoloration after 3 months, Metapex was the best material and the most discoloration rate was related to 20% CPP, and there was no difference between the 5% CPP, and 10% CPP with ZOE.

Statement of the problem: Alveolar ridge resorption after tooth extraction may interfere with optimal dental implant placement.

Purpose: This study aimed to compare the marginal bone loss (MBL) and thickness of the buccal aspect of the augmented site in simultaneous versus delayed implant placement following lateral ramus horizontal ridge augmentation in the posterior mandible.

Materials and method: This prospective cohort study was conducted on patients who required horizontal bone augmentation of the posterior mandible using lateral ramus autogenous bone graft. Patients were divided into two groups of simultaneous implant placement (group 1) and delayed implant placement (group 2). Cone-beam computed tomography (CBCT) images were obtained before augmentation, at the time of implant placement, and 10 months later (6 months after implant loading). MBL and thickness of the buccal aspect were evaluated over time.

Results: There were 18 patients in the group 1 and 16 patients in the group 2. Analysis of the CBCT scans demonstrated that the mean MBL was 1.21±0.35mm in the group 1 and 1.08±0.19mm in the group 2, with no significant difference between the two groups (p= 0.19). Thickness of the buccal aspect of the augmented site at the time of implant placement was 1.85±0.20mm in the group 1 and 2.16±0.29 mm in the group 2, with a significant difference (p< 0.001). However, data analysis regarding changes in the buccal plate thickness showed no significant difference between the two groups (p= 0.36).

Conclusion: According to the results of this study, there was no significant difference in M-BL and post-operative changes in the thickness of the buccal aspect of the augmented sites with onlay lateral ramus bone blocks between simultaneous and delayed implant placement.

Statement of the problem: Mast cells are round to elliptical cells that originate from bone marrow stem cells and enter the peripheral blood. By releasing inflammatory mediators, these cells are involved in type I hypersensitivity, wound healing, defense against pathogens, increased blood vessel formation, and destruction of the extracellular matrix. There are contradictory results regarding the role of mast cells in tumor lesions.

Purpose: Considering the contradictory results and few studies on the density of mast cells in salivary tumors, the present study investigated and compared the density of mast cells in two common salivary gland tumors.

Materials and method: In the cross-sectional study after reviewing the records of patients referred to the Pathology Department of the School of Dentistry and Shahid Sadoughi Hospital in Yazd, 15 blocks of each of the mucoepidermoid carcinoma and pleomorphic adenoma tumors were taken. After Giemsa staining of the samples, the average of stained cells in 10 random fields under 400× magnification was counted. The results were analyzed using statistical tests of t-test, ANOVA, Chi-square, and Mann-Whitney in SPSS ver. 22.

Results: The average mast cell counts in pleomorphic adenoma (4.2) was higher than muco-epidermoid carcinoma (1.7) but there was no significant relationship (p= 0.305). In mucoepidermoid carcinoma, the numbers of mast cells increased with increasing tumor grade (low: 0/467 moderate: 1/567 high: 2/983) and there was a significant relationship (p= 0.009).

Conclusion: According to the results of the present study, it seems that the mast cells accumulation may be secondarily associated with inflammatory responses due to cell accumulation and tissue destruction by tumor cells.

Rosai Dorfman disease is generally defined as a massive bilateral painless cervical lymphadenopathy accompanied with both fever and leukocytosis with neutrophilia. Additionally, it may possibly be associated with polyclonal hypergammaglobulinemia, reversal of CD4/CD8 ratio, the elevated erythrocyte sedimentation rate (ESR), microcytic anemia, and thrombocytosis. Rosai-Dorfman disease is known as a benign self-limiting disease, so no treatment is required in many cases, although it causes death in some cases by involving vital organs like kidney. The treatment is required when there is a life-threatening situation such as airway obstruction or involvement of vital organs such as kidney, liver, and lower respiratory tract. The required treatment choices include steroid therapy, chemotherapy, radiotherapy, and surgery. Surgical treatment is performed for bulk removal to resolve the obstruction caused by the mass as well as taking biopsy for the definite histopathologic diagnosis of disease. A 26-year-old man was referred to oral and maxillofacial surgery (OMFS) clinic of Taleghani hospital with chief complaints of pain and swelling of left submandibular space. According to the patient himself, the swelling had been started three months earlier. After rejecting dental source of the lesion, we decided to remove the mass by excisional biopsy concerning the patient's discomfort. Histopathology report verified Rosai Dorfman disease as definite diagnosis of the mass.

Statement of the problem: Although sumac extract (SE) is reported as a collagen cross linker, the available data regarding its effect on the dentine micro-hardness is quite sparse.

Purpose: Therefore, the aim of this study includes evaluating the effect of different concentrations of SE on dentine micro-hardness comparing to grape seed extract (GSE).

Materials and method: In this experimental study, the GSE was purchased from available market and convert to 5% solution. Meanwhile the 5, 10, and 20% of SE solutions were prepared experimentally. The base line micro-hardness of 60 samples (30 premolars divided to buccal and lingual segments) was recorded triplicate for each specimen and they were randomly divided into 5 groups (four abovementioned experimental solutions and de-ionized water as negative control). For 35 consecutive days, each sample was twice pH cycled and treated by solutions. Ultimately, the final micro-hardness was recorded triplicate again for each sample and the numerical data was compared with each other using one-way ANOVA and Tukey HSD Post Hoc tests (α=0.05).

Results: The meanSD values of micro-hardness for the groups was recorded as 54.45 13.4, 65.6518.5, 39.572.26, 41.131.66 and 43.794.96 at base line and 10.40.99, 11.85 0.75, 10.161.84, 8.481.16 and 6.311.01 at final stage for control, GSE 5%, SE 5%, SE 10% and SE 20% respectively. There was no significant difference among the micro-hardness of the groups before treatment (p= 0.369). However, after experimental treatment, there was significant difference between the groups (p= 0.024) while in pairwise comparison just two groups (GSE 5% and SE 20%) had significant difference with each other (p= 0.017).

Conclusion: The efficacy of SE was reversely related to its concentration. Moreover, neither GSE nor SE had significant effect on dentine micro-hardness after 35 day pH cycling.

Statement of the problem: The bone particles collected during osteotomy could be used as autogenous bone graft materials for dental implant surgery. Different factors such as drill design may influence its clinical viability.

Purpose: This study examined the effect of drill design on the osteoblast viability and histopathology parameters of bone collected during the preparation of dental implant site.

Materials and method: In this experimental study, 90 samples were obtained from three different bone drilling systems including Bego, Implantium, and Dio during fixture installation in patients requiring treatment at the Department of Periodontology, Dentistry University Hamedan. The MTT (3-4,5-Dimethylthiazol2,5-diphenyltetrazolium bromide) was used to determine percentage of cell viability. Samples were fixed in 10% formaldehyde for histological evaluation. Then, they were kept in 10% EDTA solution for 4 weeks for decalcification. The provided slides were evaluated regarding bone structure and osteocytes counts for assessment of viability. Tukey test and SPPS 21 software were used for statistical analysis.

Results: The result showed the viability of osteoblast obtained by Dio (0.45±0.04) was significantly better than Bego (0.37±0.05) and Implantium (0.37±0.04) systems. In histopathological evaluation, the grafting material obtained by Dio presented the best osteoblast morphology.

Conclusion: It might be concluded that drill geometry has significantly influenced the viability of bone particles collected during the preparation of implant sites .Moreover, characteristic geometry alone cannot represent the performance of a particular drill, and several geometric features should be concerned. The results of this study showed that the geometry of the Dio drill was the best considering the viability and histopathological evaluations.

Statement of the problem: Tooth-colored composites are used to repair caries lesions and other dental defects, particularly in anterior regions in children. Although a wide range of composites is using, little attention has been paid to the important indicators such as biological profiles or products released from these materials.

Purpose: The current study aimed to compare the histocompatibility and cytotoxicity of light-curing resin used to repair children's teeth with different brands (3M, DenFil, and Opallis) in curing times of 20 and 40 seconds in human oral fibroblast cells (HGF1).

Materials and method: In this in vitro study, Three types of flow composites (3M, Opallis, and DenFil), all at A2 shade, were used. The composites were at 4×2mm with separate exposure times of 20 and 40 seconds. MTT test was used to determine the cytotoxicity of composites on oral fibroblast cells. This test is based on the conversion of tetrazolium bromide to a purple compound known as formazan that its color intensity can be evaluated using the ELISA. The higher intensity of the color reveals the higher survival rate of the mitochondria, which indicates less toxicity. One-way variance analysis and unpaired t-test were used to compare the cytotoxicity of each brand in two conditions of 20 and 40 seconds of curing. Statistical significance was considered when p< 0.05.

Results: 3M and Opallis composites were significantly reduced vitality of cells compared to control group in both 20s and 40s curing status. While DenFil brand did not show marked cytotoxicity. In each brand, there are no significant deference between 20s and 40s curing times.

Conclusion: Histocompatibility depends on the type of composite resin. In the current study, DenFil brand showed the highest histocompatibility, followed by 3M and Opallis.

Statement of the problem: Obstructive sleep apnea (OSA) is an underdiagnosed and potentially serious disorder that is accentuated by edentulism. The overclosure of the mandible and a potential upper airway collapse during sleep creates challenges in treating edentulous sleep apneic patients.

Purpose: To evaluate complete dentures and mandibular advancement devices as potential oral appliances in the management of sleep apnea in completely edentulous patients.

Materials and method: The study design was a systematic review with meta-analysis. The search criteria complied with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and the keywords in population, intervention, control, and outcomes (PICO) format was systematically searched for relevant research articles published till August 2021 in an electronic database (PubMed, Cochrane, Science Direct, Ovid). Randomized controlled trials and cohort studies were included that compared the effectiveness of oral appliances on apnea-hypopnea index (AHI), airway space, and quality of sleep in edentulous sleep apneic patients.

Results: 1785 articles were derived from the initial search and based on inclusion criteria, 10 articles were systematically filtered for qualitative analysis and assessed for risk of bias using the Cochrane risk of bias tool and ROBINS-I tool. Out of the 10 articles, 5 articles were taken for quantitative analysis. The use of a mandibular advancement device (MAD) showed a decrease in AHI score, but the available data was heterogeneous to conduct a meta-analysis. The mean difference of AHI for the random effect model between the non-complete denture and complete denture wearers at sleep was -0.49[95% CI (-1.47,0.48)] events per hour, but the change was non-significant (p>.05).

Conclusion: The complete dentures as an oral appliance had reduced apneic episodes in completely edentulous sleep apneic patients, but the effectiveness cannot be solely attributed to the prosthesis in the treatment of OSA. MAD showed greater improvement in reducing AHI, however, the level of evidence was inadequate to provide a conclusive statement.

Statement of the problem: Camelia Sinenis or green tea (GT) and Teucrium polium (TP) are known to have a great antimicrobial potential on salivary Streptococcus mutans (S. mutans). Their efficacy should be examined compared to the gold standard antimicrobial agents.

Purpose: To evaluate the effects of Camelia Sinenis or green tea (GT) and Teucrium polium (TP) extracts in comparison with chlorhexidine gluconate (CHG) on salivary S. mutans levels.

Materials and method: This double-blinded randomized clinical trial study was conducted on 90 preschool children aged 4 to 6 years and assigned randomly (simple randomization) to three groups as GT, TP, and CHG. Unstimulated saliva samples were then collected in three times as before application of agents, after half an hour, and after one week. To determine S. mutans levels, quantitative polymerase chain reaction (qPCR) technique was additionally utilized. Statistical analysis was also fulfilled using Shapiro-Wilk test, Friedman test, Chi-square test, paired sample t-test, repeated measures analysis of variance (ANOVA), and Mann-Whitney U test at a significance level of 0.05.

Results: The results of this study established a significant difference between mean salivary S. mutans levels after administration of the three compounds. Although the mean of S. mutans levels reduced significantly following the application of CHG and TP after half an hour, the mean salivary S. mutans levels in the group receiving GT declined in a significant manner only one week later (p< 0.05).

Conclusion: The results of this study indicated that GT and TP extracts had considerable effects on salivary S. mutans levels compared with CHG.