Journal of Mashhad Dental School
Year:2004 | Volume:28 | Issue:1-2|Papers Count:21

Introduction: Using template is a very fast and reliable way for diagnosing and Treatment planning in orthodontics. The aim of this study, which was done for the first time in Iran, was to prepare lateral and frontal cephalometric templates for men with normal occlusion to be used for diagnosis and treatment planning of patients who need orthodontic and ortho-surgical services.Materials and Methods: 31 male students of Islamic Azad University with normal occlusion, aged 19 to 25 with the mean age of 21.3 years, were selected. After preparing files and taking impressions, lateral and frontal cephalograms were taken in NHP and cephalometric analyses were done. Data were analysed using SPSS software (student t-test).Results: 2 templates were extracted, one lateral and one frontal or posterio- frontal. Conclusion: Using template is a very fast and reliable way for diagnosis and treatment planning in orthodontics. The templates of this study, which are available and will be submitted on request, can be used for patients of the abovementioned age group.

Introduction: The objective of this study was to detect the extent of which the dentists in the city of Mashhad pay attention to the goals of taking and recording medical and pharmacological records (Medical history) of their patients.Materials and methods: A sample of 80 out of 345 registered dentists in the region were selected through simple random sampling. To collect data, a standard questionnaire (valid & reliable) based on Likert scale was prepared appropriate statistical methods including descriptive statistics, Ki Square test, One sample T -test, and Wilcoxon signed rank- test, were used for data analysis.Results: 1. Dentists in the region where the study was conducted, did not care enough for the goals of taking patients" medical history.2. Dentists" attention to the goals of recording data intermediate.Conclusion: We can deduce that the dentists need continuous education and an effective management system for evaluation of performance is necessitated.

Introduction: The purpose of this study was to determine the prevalence of oral Physiological and pathological changes of oral mucosa In Mashhad junior high school boys Materials and Methods: We prepared a questionnaire to collect the data. Totally, 300 students with the age range of 10-17 were randomly selected and examined. Results: We determined the prevalence of about 20 mucosal changes. Fordyce granules (50.4%), traumatic red lesions (18.3%) and geographic-tongue (13.6%) were the most common physiological & pathological oral mucosa and tongue changes respectively.Conclusion: In this study the prevalence of physiological and pathological changes was high. Although none of them needed to be treated, the differential diagnosis was very important.

Introduction: Diabetes mellitus is one of the most common metabolic diseases in which elevated blood glucose level interferes with activity of Polymorghonuclear (PMN) cells. Prevalence and severity of periodontal diseases in diabetic patients are also reported to be higher than no diabetics. Considering different opinions regarding the interrelationships of PMN cell dysfunction and destruction of periodontal tissues in diabetics, this study was performed. Materials and Methods: This study was a case-control one. 53 cases (22 with IDDM, 21 with NIDDM and 10 non diabetics) were selected for this study. Diabetic patients (equal males and females) were referred from Mashhad Diabetic Center. The examined parameters were PMN cell function (using NBT test), fasting blood sugar, plaque index, pocket depth, bleeding index and bone loss (using panoramic xray).The data were analyzed using One - Way ANOV A, multivariable analysis, Tukey test and correlation coefficient.Results: The fasting blood sugar level of both diabetic groups were significantly higher than that of no diabetic groups (P<0.001). The plaque index was significantly y higher in NIDDM group compared with control group (P=0.002)Bone loss was, more severe in NIDDM group than IDDM and control groups. the difference was statistically significant. PMN cell function in IDDM group was significantly lower than NIDD,M and control groups (P=0.011). Conclusion: Observing the result, it is tempting to claim that with aging and in.1he presence of suitable condition for the plaque bacteria, the periodontal disease in the diabetic patients become more severe. Prevention of the periodontal diseases will be possible provided that the blood sugar level and the bacterial plaque are controlled.

Introduction and objective: One of the most important laboratory procedures in crown and bridge construction is preparing the wax. pattern. A restoration is predictable when its marginal gap is minimum, which depends on the marginal fitness of wax pattern. Since a lot of studies related to marginal distortion of the wax pattern have been done after removing it from the working model ( die ), this study was designed to evaluate marinal fitness using different time intervals and temperatures while the wax pattern remains on the die. The purpose of this" study was to assess the marginal wax pattern fitness on the working model in different temperatures and time intervals with two types of hard and soft waxes. Materials and Methods: In an experimental study, 30 wax patterns were made on 30 truncated cone shape brass models using dipping wax technique.A brass cap was used to control the thickness of the wax, and marginal fitness. The dimensions of the brass models were 6mm x 6mm with an 8 degree convergence and a shoulder finishing line of 1mm width.15 wax patterns were prepared from hard wax (Ram in) and 15 from soft wax (Renfert). Each type of wax was divided into third groups: The first group was immersed in the water with 23°c temperature, the second group in water with 32°c temperature and the third group was stored in refrigerator at 8°c. In order to protect the wax patterns from the direct contact with the water, they were located in a brass container. This also helps in properly heat transition.The storage times for each group were 2h, 5h and 22h. The marginal vertical discrepancy was determined by a scanning electron microscope with magnification of 200 at 3 determined points.The data were analyzed with 3 way, 2 way and one way ANOV A and Duncan test. Results: 1) The maximum mean gap for soft wax (Renfert) occurred during 0-2 hours (15.23mm±4.52) and for hard wax (Ramin) during 2-5 hours (1.23mm±0.67).2) Soft wax (Renfert) showed more marginal gap at the temperature of 320e and time interval of 0-22h compard with 80e temperature and the time interval of 0-22 hour.3) Hard wax (Ramin) showed no significant difference in marginal gap at temperatures of 23°c, 32°c and 8°c even after 22h interval.Conclusions: 1) The best storage temperature for sofwax (Renfert) is 8°c.2) The best wax for marginal fitness is hard wax (Ramin) .3) The marginal discrepancy in hard wax (Ramin) was not significant clinically even after 22h.

Introduction: Anterior and posterior cross bites are observed in orthodontic patients more frequently than other malocclusions. The purpose of this study was to the determine the prevalence of anterior cross bite and posterior cross bite (unilateral & bilateral) in primary and high school students in Mashhad and comparing the results with each other.Materials and Methods: In this cross sectional study the data collection method was clinical observation and a form for recording the data.In this study 2956 students including 2050 primary school students (1030 boys and 1020 girls) with the age range of 7-12 years and also 906 high school students (490 boys and 416 girls) with the age range of 15-18 years were selected in random cluster sampling. Statistical analysis was done using SPSS software (Fisher’s exact test in two-by-two cross tabulations).Results: 1-The prevalence of posterior cross bite in primary school students was 6.9% and in high school students was 5.2%. The difference was not significant.2- The prevalence of posterior cross bite in boys in primary school was 7.8% and in high school boys was 8.4%. The difference was not significant.3-The prevalence of posterior cross bite in girls in primary school was 6% and in high girls Was 1.4%. The difference was significant.4-The prevalence of bilateral posterior cross bite in primary school students was 0.87% and in high school students was 1.6%. Unilateral posterior cross bite in primary school students was 6% and in high school students was 3.5%. The difference in unilateral cross bite was significant.(P-v=0.006) 5-In general, the prevalence of anterior cross bite in primary school students was 0.87% and in high school students was 5.4%.The difference was not significant 6-The prevalence of anterior cross bite in primary school boys was 7.8% and in high school boys was 8.6%. The difference was not significant.7-The prevalence of anterior cross bite in primary school girls was 5.3% and in high school girls was 1.6%. The difference was significant. (P-v=0.002)Conclusion: In this study anterior and posterior cross bites in primary school students were more than high school students. The difference was not significant. Unilateral cross bite was more frequent in primary school students than high school students. . The difference was significant.Bilateral posterior cross bite in high school boys was more than primary school boys but in high school girls was less than primary school girls. Anterior and posterior cross bite in high school girls decreased and in high school boys increased significantly compared to primary school students.

Introduction: At the end of an orthodontic treatment, the coordination between different facial dimensions is very important. The changes in facial height cause changes in other dimensions. In the present study, the relationship between lower third of facial height and maxillary and mandibular lengths was evaluated and compared with the previous studies.Materials and Methods: In this study, 38 lateral cephalograms of Mashhad high school students aged 16- 19 with mean age of 17 years were selected and traced manually. The profile, occlusal relationship, overjet and overbite in these cases were normal and molar and canine relationships were class I. The data were analyzed using SPSS software (version 10) and t-student test was used for analysis. Results: The findings were as follow:• The relationship between lower third of facial height and both the length of mandibular base and the length of mandible based on Harvold analysis was significant.• The relationship between the lengths of both the maxilla and anterior cranial base, and lower third of facial height were not significant.• No relationship was found between the length of maxillary base (based on Harvold analysis) and lower third of facial height.Conclusion: According to this investigation it is concluded that the length of mandibular base has a significant correlation with the lower third of facial height, but such a correlation does not exist between ma.xil1a and lower third of facial height.

Introduction: Mucoepidermoid carcinoma is the most common salivary gland malignancies, classified into three categories as low, intermediate and high.Because of its highly variable biologic potential, identification of patient’s status histological and proper classification is of high importance in treatment and finally prognosis. Materials and Methods: 20 samples with the diagnosis of MEC were selected from the archive of the or maxillofacial pathology department of Mashhad dental school and Ghaem and Omid hospitals which included five samples of grade I, seven samples of grade II and 8 samples of grade III mucoepidermoid carcinoma.Three sections were taken from each specimen. The first section was stained with H & E, the second one by. AgNOR technique ana the last one with Ki-67 immunohistochemically. In each sample, the number of AgNOR dots in the nuclei of 100 cells and the number of brown nuclei which expressed Ki-67 in 100 cells were studied.Results: 1.There was a significant correlation between salivary gland MEC histological grades and number of AgNOR dots. (rs=0.791 , P value=0.00) 2.A significant correlation was detected between salivary gland MEC histological grades and ki-67 expression. (rs=0.893 ,P value=0.00) 3.The findings in our study (AgNOR dots & ki-67 expression) were slightly different between grades I and II but the difference between the first two grades and the last grade was highly significant.Conclusion: Use of any of the two proliferating markers mentioned above (AgNOR and Ki-67) is suitable in detection of histological grades of salivary gland MEC. Considering the highly significant difference between the last grade and the first two grades, MEC classification as low grade and high grade is suggested.

Introduction: Implant supported over dentures may be used as an alternative to fixed bridges especially in edentulous patient who can not afford the high cost of fixture placement The over denture may be attached to the implant by one of several methods. One of them is magnet. Advantages with magnet include a simplified dental technique and reduced lateral stresses on the abutment. The aim of our study was to determine the rate of success rate of magnet in implant supported over dentures through clinical and histological analysis.Materials and Methods: Seven patient received above over dentures with magnetic retention. The course of study was 4 years. The patient had been edentulous for several years and were unable to function with a lower denture due to lack of retention and stability. Such a problem had not been solved by a conventional approach. The implants and magnet selected from Dyna company.Results: The use of implant and over denture with magnetic attachment was "an appropriate alternative for patients who have totally flat jaw and no better option than magnet over denture. In this study, two magnets with 500gr/f yielded a good retention for prosthesis so nutrition, phonetic and esthetic needs were resolved. No side-effect from magnet on peri-implant soft tissue was observed. The gingival sulcus was 2.08mm and the bone loss was 1.23mm after one year.Magnet resistance to corrosion was very little and the need for changing of magnet after the course of study was obvious.Conclusion: Use of magnet and over denture supported by implant in patients with totally flat jaw, who could not be treated by any other technique, is an appropriate alternative.

Introduction: Effective communication between physician and patient has a positive effect on different aspects of medicine and increases patient’s satisfaction. Nowadays, communicative skills training to medical professionals in order to foster knowledge, attitude and communicative skills is emphasized. Now, over focusing on technical cares and its expansion leads to use of ineffective communication methods traditionally, therefore key problems and. main patient’s issues remain unclear. This study was done in order to assess and analyze dental graduate students" communicative skills and the related effect on patients" satisfaction.Materials and Methods: 30 first year graduate students of dentistry and 30 patients of them were selected randomly. Film taking, interaction analysis system (IAS) and observation checklist were used for gathering data. A questionnaire was used for patient’s satisfaction. Content validity was used for validity and Alfa test for reliability. Data were analyzed by descriptive, analytical statistics using SPSS software.Results: According to results, 43% of students in all of the communication skills fields, 63% in the socio-emotional skills, 20% in diagnostic field and 27% in the consultation & education field were in a desired level. In all of the assessment fields, by increasing communication skills, the patients" satisfaction increased. ANOV A test showed significant difference between mean of patients" satisfaction by communication skills leveling the all of fields . ANOVA in all the fields and in every 3 fields showed significant difference between mean of patients" satisfaction score (P<0.05). Correlation test also showed linear correlation between communication skills and satisfaction. Correlation coefficient for communication skills in all of the fields and socio-emotional field was 0.01 and in the other two fields of diagnosis and consultation was b.05 and significant. The linear equation supported this correlation too. Conclusion: Communication skills are integral parts of physicians" clinical skills. We can increase the patients" satisfaction by proper use of verbal and nonverbal communication skills such as respect to patients, sympathy, using open-ended questions, active listening and using understandable vocabulary. These skills can also increase effectiveness of medical interview and treatment too. It is obvious that medical education administrators and instructors should plan training courses for fostering communication skills for medical students and staff.

Introduction: Successful endodontic therapy depends on a well-adapted filling in conjunction with sealer after canal preparation. A properly placed coronal restoration should complete the task of the therapy Frequently; the roper restoration requires the placement of a post and core., Therefore, the possible effect of a post space preparation on the quality of the apical seal becomes important.The purpose of this study was to compare the effect of immediate and delayed post space preparation on apical seal using two currently used sealers (AH26 or Roth sealers) with different properties.Materials and Methods: Seventy six freshly extracted single root teeth were used in this study. Teeth were randomly divided into four groups. .In addition to 15 experimental teeth in each group, there were 2 positive controls and 2 negative controls.All root canals were instrumented and filled with lateral condensation of gutta-percha and AH26 sealer in group 1 and 2 and Roth sealer in group 3 and 4. In groups 1 and 3, post space was immediately prepared with peeso-reamers, leaving 5mm of remaining filling. Teeth of group 2 and 4 were placed in 100% humidity and 37.c for 1 and 2 weeks respectively. Then the post space was prepared in the same manner as former groups. After that, the teeth were immersed passively in India ink for 3 days. Finally the teeth were washed and cleared with use of%5 nitric acid and methyl salicylate.The extent of dye penetration was determined with use of stereomicroscope and by two independent observers. The data were obtained and then analyzed statistically.Results: The lowest and highest rates of dye penetration were detected for group I and group 4 respectively.There was a significant difference between the immediate and delayed post space preparation, but such a difference, was not perceived between two sealers. Conclusion: The immediate preparation of post space after obturation and before setting of the sealer, is recommended. In this manner, the voids and the gaps created with post space preparation would be filled by flow of unset sealer.

Introduction: Adhesive restorations in endodontically treated posterior teeth could increase the strength of teeth and decrease the micro leakage. The aim of this study was to evaluate the effect of flow able composite as a liner as well as an internal splint. agent on bond strength of endodontically treated molars restored with amalgam.Materials and Methods: This study was an interventional study which evaluated the fracture resistance of endodontically treated molars in two groups based on cavity preparation of class Il MOD or MOD in combination with lingual cusp reduction. Each group was divided into four subgroups and restored with: I and 2) Tetric Flow and amalgam with and without prefabricated post. 3 and 4) Copalite and amalgam with and without prefabricated post. The control group consisted of intact molar teeth. After the restorations were made, the specimens were stored at 37°c with 100% humidity for 24 hours and then submitted to the load cycling (500,000 cycles) simultaneously with thermal cycling (5°c and 55°c). Analysis of data was done by ANOV A and Duncan test with 95% significance level.Results: Two factors (Post and cavity preparation) had a statistical interaction with each other (P<0.05). This means that without post, amalgam cuspal coverage restorations were able to increase the fracture resistance of teeth significantly but with post they were not able to do so. Post and Tetric Flow had no effect on fracture resistance individually (P>0.05), and control group showed the most fracture resistance (P<0.05).Conclusion: In patients with suitable occlusion, lingual cusp reduction and restoration with amalgam without intracanal pin could be an acceptable treatment.

Introduction: Amalgam and adhesive resin cores with prefabricated dowels are commonly used to restore endodontically treated teeth. These restorations have been widely studied": for their mechanical properties; however, less is known about their sealing ability. The purpose of this study was to compare the intracranial micro leakage of amalgam and adhesive resin cores (coremax).Materials and Methods: In this interventional study, 30 intact human single root premolars were randomly divided into two groups each with fifteen teeth. Class V cavities with the dimension. of 4mmx5mm were prepared on the buccal surface of each tooth with gingival margin in cementum and the cavity to be passed through the canal orifice.Then one group was filled with amalgam (oralloy) and another group with Coremax II according to manufacture’s. After thermo cycling and dye penetration, the teeth were sectioned and micro leakage was assessed under a stereomicroscope SPSS software (version II) was used for data analysis (student Hest).Results: The mean micro leakage of intracranial dye penetration of Coremax II was not significantly different from amalgam although it was greater for Coremax II compared to amalgam.(P-value= 0.720) Conclusion:Amalgam cores have less micro leakage than adhesive resin cores but there was no significant difference between them.

Introduction: Diabetes mellitus might result in increasing of dental caries prevalence due to xerostomia and hyperglycemia, and also might result in decreasing of dental caries prevalence due to limitation in sugar consumption. This study was done to assess the prevalence of dental caries in diabetic children and adolescents and compare it with nondiabetic sex and age -matched group.Materials and Methods: The sample was selected through convenience sampling in two groups: Group one consisted of 68 individuals (5-18 years old; case group ), suffering from type I diabetes mellitus registered at Khorasan diabetes research center. Another group consisted of 68 non-diabetic controls, who were out - patients of orthodontic department of Mashhad dental school. The data were collected through a questionnaire, medical .records and clinical examination. DMFT and dmft indices were assessed in each patient. The data were analyzed statistically.Results: I-Mean DMFT were 4.5 ±4.7 and 5.7± 4.0 in diabetics and non- diabetics respectively 2-Mean dmft were 5.4 ± 3.1 and 5.1± 2.7 in diabetics and non-diabetics respectively.Coclusion: The main results of the survey revealed that the prevalence of dental dries in permanent teeth was significantly lower in type I diabetic children than sex and age - matched non diabetic ones but no significant difference was found between the two groups regarding the prevalence of dental caries in primary teeth.

Introduction: The reaction of polymerization can be controlled by the light exposure pattern and the temperature. The purpose of this study was to evaluate the effect of different light exposure patterns and composite temperatures on micro leakage of light cured composite resin restorations. Materials and Methods: In this interventional study, class V cavities were prepared on 200 extracted human molars. Then the teeth were randomly divided into four main groups according to different light exposure patterns of High Intensity Program (HIP), Low Intensity program(LOP), Pulls Program(PUL) and Suggested Progressive Program(SUP) . and 5 subgroups according to different temperatures of composite during curing (5°c, 20°c, 35°c, 50°c and 65°c). After thermo cycling and dye penetration, measurement of micro leakage was done using a stereomicroscope. The data were analyzed using SPSS software (ANOVA).Results: ANOV A showed that both in enamel and dentinal margins, a significant decrease in micro leakage has occurred in SUP group. Micro leakage in enamel and dentinal margins was significantly higher in HIP group than the other groups. No significant difference was observed in the rate of micro leakage among the 5 subgroups with different temperatures.Conclusion: SUP light curing pattern could be considered for improving composite resin restorations as a superior light exposure pattern due to its ability in Polymerization control, reducing polymerization shrinkage stress and micro leakage. Prewar Ming of the composites is a practical and easy way to improve composite properties for dental restorations.

Introduction: Dentists will be able to overcome the child’s behavior problem in dental clinic by anticipation of his behavior and application of appropriate management strategies to treat an individual child’s patients.The aim of this study was to assess the possibility of anticipation of children’s behavior by their mothers" personality.Materials and Methods: In this cross-sectional and descriptive analytic study, 104 healthy children aged 3-6 years without a previous history of dental visit and their mothers were selected." At the beginning of the study, mothers" personalities were determined using a questionnaire and a 15 minute interview by a psychiatrist and were categorized in four groups as normal, depressive, with anxiety, and obsession personality. Then the children’s behavior was classified according to Frankl behavioral rating scale during three different dental visits of oralixamination, fluoride therapy and restorative dental treatment, without consigering their mothers personality.Finally; the relationship between behavioral scores of children and their mothers" personality traits were statistically analyzed using ANOVA test.Results: This study revealed a significant positive association between the mean behavioral score of children and their mothers" personality traits only at the first visit arid the difference between the mean behavioral score of children with obsessive mothers and those with normal personality traits was significant(P=0.02) Conclusion: Mothers" personality affected the children’s behavior only during the first dental visit.

Introduction: Although odontogenic sinusitis is a rare entity when compared to the sinus dispases of rhinogenic origin, it is extremely important to identify a dental etiology when it occurs. The offending tooth or teeth would thus require endod6ntic treatment or extraction, and the sinus disease should carefully be assessed and appropriately managed. In the patients with pain and tenderness on the maxillary sinuses, odontogenic origin is suspicious. Materials and Methods: This is a one-year retrospective study on 38 patients followed in the ENT ward of Ghaem Hospital, Mashhad University of Medical Sciences. Most of patients were 20-30 years old. Results: In all, sinusitis was most common in ethmoid and maxilla, with the symptoms of mostly nasal obstruction and postnasal discharge in the last 3-6 years. 5 patients out of 38 (13.2%) had odontogenic sinusitis. An important point is that patients who had sinusitis with odontogenic origin were older than 35 years (more than the average age of these 38 patients), Their most complaints were a local pain and tenderness on their cheek and upper jaw.Conclusion: An exact attention to the patient with complaints of pain and tenderness on the maxillary sinus sometimes reveals the odontogenic origin for the sinusitis. In these cases a close cooperation between the ENT specialist and the dentist is an essential factor.

Introduction: Restoration of defects in coronal one-third of the root is difficult. Forced eruption is a procedure for treatment of these defects. The purpose of this study was to evaluate clinical and radiographic aspects of this technique suggested by Simon.Materials & Methods: In this study 12 patients with defects in coronal one-third of root were selected and treated. The defects of the selected teeth were caries (2 patients), accidental perforation (l patient) and root fracture (9 patients). Results: The clinical and radiographic results of this study showed that forced eruption technique suggested by Simon was successful in all patients. Conclusion: According to the above findings, this technique can be used in treatment of defects in coronal one-third of the root.