JOURNAL OF ISFAHAN DENTAL SCHOOL
Year:2007 | Volume:3 | Issue:2|Papers Count:11

Introduction: The survey was aimed to immunohistochemical evaluation of P53 expression in dental follicle and dentigerous cyst according to the capability of creating neoplastic changes in dentigerous cyst.Methods and Materials: Twelve cases of dentigerous cyst which has been supplied from archives of oral and maxillofacial pathology department of Babol School of Dentistry, from March 2004 to March 2006 and twelve cases of dental follicle supplied from surgery of impacted third molar of people visited oral and maxillofacial surgery department of Babol School of Dentistry during 2006 were selected. Five microns slices were gotten from paraffin block stained with P53 antibody, using immunohistochemical procedure. The observing of all the stained slides was done according to H-score gradation; it has been considered a degree of staining intensity of epithelial cells and the percent of stained epithelial cells. Then the aggregate of these two elements announced as final score. The results analyzed with Mann Whitney test using SPSS software.Results: The expression of P53 in dentigerous cyst was more than dental follicle (p value = 0.001). In relation with the percent of cells stained by P53 (p value < 0.0001), this difference was more than intensity of staining (p value = 0.021).Conclusion: The expression of P53 in dentigerous cyst was more than dental follicle. It seems we can distribute this difference to the capability of creating of neoplastic changes in dentigerous cyst.

Introduction: Neural based tests responses have some limitations. In these years pulse oximetry has used to measure oxygen saturation of pulpal blood circulation. Due to thickness of dental pulp, it is blood oxygen saturation may be lower than peripheral blood. This study has compared the difference of blood oxygen saturation in anterior dental pulp with peripheral blood using ear pulse oximetry probe.Method and Materials: We selected 100 healthy persons with the age of 24–34 years with normal anterior teeth. Then oxygen saturation of anterior, superior and inferior teeth and ear was measured with pulse oximetry with ear probe. Data was analyzed with independent sample test and t-paired test using SPSS software.Results: Mean oxygen saturation in ear was 98.5% (± 1.5), and 92.38 (± 3.3) in 400 selected teeth. According to t-paired test, there was no significant difference between oxygen saturation in ear and teeth. There was no significant difference of oxygen saturation between different teeth.Conclusion: In our study oxygen saturation was above 90%. As in non vital pulp oxygen saturation is zero, this point can help dentists for correct diagnosis in pulp vitality. Oxygen saturation in teeth was lower than peripheral blood.

Introduction: The aim of this study was to evaluate the effectiveness of a didactic and practical oral health education program to improve oral health knowledge among primary school children.Methods and Materials: The participants were 560 children, 9-11 years old, selected from different geographic areas of Isfahan with stratified random sampling method. This oral health education project consisted of one classroom-based lesson with hands on training reinforced by practical session for tooth brushing and flossing. Just after two months and one week following the program, a validated and reliable questionnaire was used to demonstrate children's oral health knowledge prior (Chronbach alpha = 0.74). The collected data were analyzed by SPSS software with repeated measurement ANOVA and Cochrane statistical tests.Results: The mean grade of the knowledge from the maximum of 100 was 45 ± 16.7 prior to the intervention. Following the program this grade increased to 78± 20.2 which showed a significant improvement in oral health knowledge (p value < 0.001). Two months and one week after the program, the mean of knowledge was 78 ± 19 and 79 ± 17.7, respectively. No significant loss of knowledge was detected (p value = 0.36).Conclusion: Based on this study, the oral health education program implemented in Isfahan community dentistry center, improved the level of knowledge in this age group. Moreover, its efficacy to produce a stable increase in oral health knowledge was shown.

Introduction: The aim of this study was to compare the sealing ability of two temporary restorative materials, Cavit and Coltosol, in different times by dye penetration method.Methods and Materials: Seventy extracted human anterior teeth were collected. Standard access cavities were prepared and then teeth cleaning until 40 and shaping until 70 were done. The canals were then obdurate with gutta-percha and AH26 sealer. Samples were divided into five groups: three experimental groups (20 in each one) and two positive and negative control groups (5 in each one). Access cavities were prepared in experimental and positive control groups and pulp chambers were completely excavated. Access cavities of experimental groups were sealed by one particular material using incremental method; but positive control teeth were not sealed. Then all groups were kept in incubator at 37oC; first group for 1 day, second group for 1 week, and third group for 1 month. After the determined time, all groups were immersed in blue metylen separately. Then the linear extent of dye penetration was measured. Results were analyzed by one-way analysis of variance.Result: There was statistically significant difference in leakage between all groups at different times (p value < 0.001).Conclusion: Coltosol was found to exhibit better seal comparing cavit. Microleakage will be increased by time.

Introduction: Recently, there is a growing interest in the role of nitrate and nitrites in protecting against oral and gastrointestinal diseases. In human, ingested nitrate absorbs into the blood and concentrates in the salivary glands rapidly changes to nitrite. Nitrite may then be acidified through encounter with the plaque micro flora. The acidification of nitrite produces a mixture of nitrogen oxides as well as nitrous acid. Nitrous acid will spontaneously decompose to produce nitric oxide (NO). NO participates in the nonspecific defense mechanisms of the oral cavity to prevent bacteria from overgrowing. The aim of the study was to determine the correlation of nitric oxide with dental caries in children in mixed dentition period.Methods and Materials: 3 ten-member groups of children aged 6–12 years old were selected according to decayed and filled surfaces (dfs); with dfs < 1, 1< dfs < 5, and 5 < dfs > 10. A 2ml sample of saliva of each child was taken and transferred to laboratory, where by using the chromatograph unit, NO concentration was measured. Data was analyzed by ANOVA and t-tests.Results: Based on the laboratory findings, NO concentration in dfs < 1 group showed significant difference with other groups; but there was no significant difference of the NO concentration in groups with 5 < dfs < 10 and dfs > 10.Conclusion: The NO levels were higher in high dfs groups. NO production might be a host defense mechanism when dental caries increases.

Introduction: Furcal perforation is a common accident during endodontic treatment. Prognosis of furcal perforation repair is determined by several factors. One of these factors is sealing ability and biocompatibility of materials used to repair furcal perforation. So far, different materials have been suggested for repair of furcal perforation. One of these materials that based on investigations has shown agreeable properties and clinical success when used as repairing material for furcal perforation is MTA. Since Proroot MTA is very expensive and not easily accessible for all dentists, we decided to evaluate microleakage of MTA produced in Iran. In this in vitro experiment, sealing abilities of Proroot MTA, Root MTA (Iran-MTA), Amalgam and One coat bond in repairing furcal perforations was compared.Methods and Materials: Furcal perforations as 1mm diameter defects were created in 60 extracted maxillary and mandibular molars. The teeth were divided into four equal groups. Each group was sealed with one of the materials. The crowns of teeth were restored by amalgam. Then dye penetration test was done. A longitudinal sectioning was performed. Samples were studied under stereomicroscope and data were analyzed by means of Duncan statistical test.Results: The results showed that no significant difference in sealing ability was found among Proroot MTA, Root MTA (Iran- MTA) and one coat bond (p value > 0.05). But there was a significant difference in sealing ability between Root MTA and Amalgam (p value < 0.05).Conclusion: Root MTA can be an acceptable substitute for Proroot MTA.

Introduction: Histiocytosis of lagerhans cell is a spectrum of disorders characterized by proliferation of Histiocyte like cells and includes following: Eosinophilic granuloma, Hand– Schuller Christian disease and Letterer- Siwe disease. The incidence is 0.5 in 100000 person per year in individuals younger than 15 years old.Case Report: The patient was a 57 day old male infant referred with papulovesicular cutaneous and exophitic oral lesions without bone and visceral involvement. Diagnostic procedures until final diagnosis of Langerhance cell Histiocytosis and treatment of this case have been reported.Conclusion: Oral lesions could be the first manifestation of disease and dentists should be aware of that. According to different investigations, the disease may have a genetic basis.

Introduction: Radicular and residual cysts are by far the most common cystic lesions in the jaws which consist 50-75% of all oral cystic lesions. Radicular cysts have been considered rare in the primary dentition. It has been suggested that pathogenesis of radicular cysts in primary and permanent dentition could be different; although caries and pulp infection still are the most important of all. After extracting or shedding of the causative tooth, the cyst remains in jaws and from now on is considered a residual cyst.Case Report: A 12 years old female patient came to our clinic because of a painless swelling in the lower back region of her left jaw. According to surgical and microscopic findings, the lesion was diagnosed a radicular cyst associated with her 2nd deciduous molar and had a pulp treatment. The cyst was enucleated.Conclusion: Although radicular cysts in deciduous dentition is considered to be rare, but it has been seen in primary molars treated endodontically which could be due to remaining of infection in inaccessible parts of root apex or periapical irritation with formocresol containing materials used in root canal filling. Assuming that the pathogenesis of radicular cysts is identical in primary and permanent dentition, the low frequency in the former is yet to be clarified.