مجله دانشکده دندان پزشکی اصفهان
سال هفتم شماره 5 (پیاپی 28، زمستان 1390)

The ability to accurately measure forces produced by orthodontic appliances during orthodontic treatment is desirable. The aim of the present study was to compare forces measured by mechanical formulae designed with a software program and those experimentally measured by a dynamometer to find a scientific way to determine the exact amount of activation needed for applying a force within the optimum range. In this in vitro study, at first the formulation of force applied by canine retractor spring was determined with the aid of mechanical sciences. To confirm the accuracy of the formulation, 50 springs made of different wire diameters, working arm lengths, different number and diameters of helices and with different designs, the number of which had been determined by a pilot group, were examined and the results obtained from the formulation and dynamometer were compared. Paired t-test was used for statistical analysis (α = 0.05). The difference between the measurements made by the dynamometer (mean = 65) and those determined by the formulation (mean = 65.88) was 0.8842 gr, which was statistically significant (p value = 0.003). Under the limitations of the present study, it appears formulations can be used to determine the amount of spring activation and the software designed for such a purpose facilitates the use of the formulation.

An important step in retreatment of root canals is removal of filling materials and sealers from the root canal. The aim of this study was to compare the efficacy of rotary and hand files in removing gutta-percha and sealer from the root canals. In this in vitro study 58 extracted human anterior teeth were collected. Standard access cavities were prepared after radiography. The canals were prepared using the step-back technique and obturated with gutta-percha and AH26 sealer. The teeth were divided into two experimental (n = 24) and two positive and negative control (n=5) groups. In one experimental group Gates-Glidden drills and Hedstrom files were used with chloroform to remove the filling materials from the canals and in the other Flexmaster and Hero 642 rotary instruments were used. In the negative control group 5.25% sodium hypochlorite and EDTA were used to achieve clean canals without any debris. In the positive control group the teeth were placed in an incubator without removing canal fillings. Then the teeth were split longitudinally and dyed with hematoxylin. Total canal surface area and area of remaining material in the apical, middle, cervical thirds of the canals were measured under a stereomicroscope and their ratio was calculated as percentage of remaining debris. Data were analyzed by t-test and paired t-test at 95% confidence interval. The means of remaining filling materials in the entire canals in hand and rotary file groups were 4.73 and 5.85, respectively (p value = 0.05). Comparisons of the percentages of remaining filling materials in the entire canal lengths and in corresponding segments of the canal did not reveal any significant differences between the two groups (p value = 0.475). None of the two techniques evaluated was able to completely remove filling materials from the root canals, especially from the apical third.

Implants are commonly used in the treatment of fully or partially edentulous patients. Placement of implants requires careful radiographic evaluation of the surgical site so that side effects and neurovascular trauma to the superior wall of the mandibular canal would be avoided. The aim of this study was to assess the accuacy of spiral tomography, panoramic views and parallel periapical radiographic techniques in evaluating the distance between the alveolar crest and the superior border of mandibular canal. Three dried human mandibles were used in this descriptive/analytical study. Three metal pieces were glued to the left side and three to the right side of each mandible. Subsequently, a 5-mm-thick layer of wax was placed on the surface to simulate the soft tissue. Periapical and panoramic radiographs and spiral tomographs were taken from each mandible. Then the mandibles were sectioned and the actual distance between the alveolar crest and the superior border of mandibular canal was measured in each region. Data was analyzed by t-test and repeated measures ANOVA (α = 0.05). The results showed that of the three techniques evaluated only periapical radiographs did not exhibit any significant differences from the actual measurements (p value < 0.05). In addition, there were no significant differences between panoramic and tomographic techniques (p value < 0.05). Based on the results of the present study, parallel periapical technique is recommended for evaluation of implant placement sites and measuring of bone height in the mandible, although tomography can be used to measure bone width.

Natal teeth are present at the time of birth. The etiology of these teeth is still unknown but some investigators suggest the association of these teeth with various syndromes or developmental disorders. The aim of present study was to evaluate the prevalence of natal teeth in newborn babies in Isfahan. This cross-sectional descriptive/analytical study evaluated all the infants born from August 1997 to August 1998. Data was collected by questionnaires, which included data such as birth date, gender, height and weight at the birth, number of natal teeth and their location, history of natal teeth in the family, state of the nervous, cardiovascular and genital system and developmental disorders. Data was analyzed using Pearson’s and chi-squared tests (p value ≤ 0.05). A total of 31940 infants were born during the period in Isfahan. A total of 26 natal teeth were found in 17 newborn babies; therefore, the prevalence of natal teeth in Isfahan was 1 in 1878 births. 58.8% of the infants with natal teeth were male and 41.2% were female, with significant gender preference for males (p value < 0.05). Of the 24 natal teeth 92.30% were lower central incisors, 60% of which were bilateral, followed by maxillary central incisors and molars (3.84% each). Six infants with neonatal teeth had a family history of such teeth, which was statistically significant (p value < 0.05). None of the infants with natal teeth had developmental disorders or syndromes. Natal teeth are not very common. However, knowledge about how to manage these structures is essential for the general well-being of the child. Further studies on different ethnic groups are required to better understand etiology and nature of natal teeth.

Age estimation is important in many fields, including pediatrics, forensic medicine, orthodontics, etc. The aim of this study was to evaluate the accuracy of dental age estimation in 5-17 year-old children in Babol using Demirjian method.

In this retrospective cross-sectional study 301 panoramic radiographs of 183 girls and 118 boys referring to Babol dental clinics were evaluated. Simple sampling method was used. Based on Demirjian method two dental radiologists calculated the dental maturity score (DMS) by assessing the seven left mandibular teeth and estimated the dental age for each case. The chronologic age of each patient was obtained from demographic data. Finally, the correlation between estimated dental age and chronologic age was determined by Pearson’s correlation coefficient using SPSS statistical software (α = 0.05).

Mean dental age in all the subjects was estimated 0.04 year less than the chronologic age. Pearson’s correlation coefficient between estimated and chronological ages was 0.968, indicating statistical significance (p value < 0.001). In addition, there was no significant difference between estimated and chronological ages (p value = 0.31).

Based on the results of the present study, Demirjian method is sufficiently accurate to estimate dental age of children in Babol is and can be used acceptably.

Oral health in pregnant women might influence the health of the mother and infant. Dental procedures during this period should be carried out in a way that will not have any detrimental effects on the mother and fetus. The aim of this study was to evaluate knowledge and attitude of dental practitioners in Esfahan of measures taken during pregnancy. A total of 75 dental practitioners in Esfahan participated in this descriptive study by completing a questionnaire containing 20 questions (14 for knowledge and 6 for attitude) in relation to dental procedures during pregnancy. SPSS software and chi-squared test were used for data analysis (α = 0.05). The mean of awareness scores of dental practitioners of measures taken during pregnancy was 62%, which is rather favorable. The mean of awareness scores of dental practitioners of measures taken after delivery was 45%. The mean of awareness scores of dental practitioners of dental materials suitable for pregnant women was 49%. The overall mean of awareness and attitude scores of dental practitioners in Esfahan in relation to measures taken during pregnancy was acceptable; however, the mean score should increase by raising awareness level. More attention should be paid to educational courses on treatment measures for patients with special conditions, including pregnant women.

Before placing the dental implant, the surgeon needs to know the real height of bone in the site. Improper assessment of the distance between implant and vital structures can cause trauma to vital structures. The aim of this study was to determine the spiral tomography accuracy in evaluation of bone height in the posterior maxilla for placement of dental implants. In this descriptive cross-sectional study of 30 patients referring for implant placement 28 locations were selected for implant placement. All the patients underwent spiral tomography techniques and bone heights were reported. After implant placement the patients underwent panoramic radiographic techniques. Since the dental implant height was known the magnification of the panoramic radiographic technique in that area was determined. The bone height on the radiogram was determined in the area using a ruler at a magnification of ×3. Then the actual bone height was determined. Data was analyzed with paired t-test (α = 0.05). Comparison of the values reported by the tomographic technique with the actual bone heights revealed a measurement error of 0.7 mm by the tomographic technique, which was statistically significant (p value = 0.031). Spiral tomography can accurately determine height of bone from the maxillary alveolar crest to the floor of the maxillary sinus, preventing damage to the maxillary sinus. Therefore, this radiographic technique can be used to determine the size of the implant needed to increase success rate.

Great advantages of digital radiographic techniques have resulted in ever-increasing use of these techniques by dental practitioners. Contrast, density and other factors influecing the diagnostic quality of digital systems can be manipulated. The aim of this study was to compare diagnostic accuracy of two digital radiographic systems of Schick and Sordex in standard and high-resolution modes in the detection of interproximal caries. In this in vitro study twenty-four extracted human premolars with interproximal caries were selected and divided into four groups. Each group was radiographed using the two Schick and Sordex systems. The sensors in the two systems were fixed at 10-mm and 100-mm distances from the teeth and the tubes, respectively. All the radiograms were coded by an oral radiologist at standard and high-resolution modes in a blind manner. The teeth were sectioned in a mesiodistal direction in order to confirm caries diagnostic accuracy and determine its depth as a gold standard and coded by an oral pathologist under a stereomicroscope. Data were analyzed using Spearman’s correlation coefficient and gamma test at 95% confidence interval. There was significant relationship between the results of different digital radiographic techniques and pathologic evaluations (p value < 0.001). The highest correlation with pathologic results were observed in radiograms taken in the standard resolution mode of Schick radiographic system. Under the limitations of the present study, it can be concluded that the diagnostic accuracy of Schick radiographic system in the standard mode is highly appropriate for detection of interproximal caries.

The influence of third molar eruption on vertical facial growth has been evaluated less frequently by researchers. The aim of this study was cephalometric evaluation of the effect of third molar eruption on skeletal facial height. The subjects in this cross-sectional/analytical study consisted of thirty patients with four completely erupted third molars with proper occlusal relationships (group A) and thirty patients without third molars (group B). All the subjects were 19‒24 years of age and had Class I occlusal relationship. None of the subjects had received any orthodontic and surgical treatment. Cephalograms of subjects were traced carefully. The mean of parameters measured in both groups were compared by independent t-test (α = 0.05). Means of Frankfort mandibular angle (FMA) in groups A and B were 32.26 ± 5.82 and 27.20 ± 2.53 degrees, respectively, with significant differences between the two groups (p value = 0.001). Means of gonial angles in groups A and B were 123.86 ± 1.26 and 124.5 ± 4.88 degrees, respectively, with no significant difference between the two groups (p value = 0.491). Regarding ANB and SNA angles, no significant differences were observed between the two groups (p value = 0.335) and (p value = 0.127), respectively. However, there were significant differences between the two groups in relation to SNB angle (p value = 0.05). There were significant differences in relation to posterior facial height: anterior facial height ratios and sella‒ nasion distances between the two groups (p value = 0.001). However, there were no significant differences between the two groups in relation to nasion‒ menton distances (p value = 0.733). Craniofacial development in patients with completely erupted third molars is different from those with no third molars. Patients with third molars have larger FMA angles and greater posterior facial height (PFH). Eruption of third molars does not influence the gonial angle.

Marginal adaptation of cast restorations is essential for their long-term success. As dentists usually assign ditching of dies to laboratory technicians, and ditching has a significant effect on marginal adaptation, the aim of this study was to compare ditching by laboratory technicians and standard approach on marginal adaptation of cast restoration. In this laboratory experimental study a metal-ceramic preparation was carried out on an acrylic left mandibular first molar with a heavy chamfer finish line. Thirty working casts were obtained, 25 of which were ditched by laboratory technicians working in Isfahan and 5 others were ditched by a prosthodontist according to a standard approach. Then, castings were made on the ditched dies and vertical marginal discrepancies were measured in both groups under a stereomicroscope and with the use of a digital camera on four tooth surfaces. Data was analyzed using t-test and ANOVA. Statistical significance was defined at p value < 0.05. Mean vertical marginal discrepancies of all the tooth surfaces were 436.03 ± 318.04 and 117.17 ± 83.49 microns in the laboratory technician and standard groups, respectively, with statistically significant differences between the two groups (p value < 0.0001). However, there were no significant differences between the means of vertical marginal discrepancies in the standard (p value = 0.95) and laboratory technician (p value = 0.58) groups. Based on the results, ditching by dental practitioners is more accurate. It appears provision of educational program for laboratory technicians on ditching dies and referring the questionable cases to dental practitioners are essential.

Patients, health care workers and dental practitioners are exposed to oral infections and infective microorganisms during dental imaging procedures. The aim of this study was to evaluate awareness of dental practitioners in Bushehr of infection control techniques during dental radiographic procedures. In this descriptive study knowledge of dental practitioners working in Bushehr about infection control in dental radiography was evaluated by a specially designed questionnaire. The questionnaire was distributed during continuous education conferences and was directly handed in to dental practitioners in their offices. A total of 47 dental practitioners were evaluated. Data was analyzed by descriptive statistical methods in the form of scores ranging from 0 to 100. A total of 74.5% of those surveyed in the study were male and 25.5% were female. The awareness scores in relation to infection transmission pathways, infective fluids, AIDS transmission pathways, and unhealthy behaviors were higher than average. The awareness scores in relation to covering of the hands, environmental factors, how to wear new gloves, and disinfection of the hands were below average. The total mean of the correct answers to the questions was 45% with a range of 6% to 87%. In general, awareness scores of dental practitioners in Bushehr of techniques to control infection during dental radiographic procedures were at a moderate level. Considering the importance of infection control in dental radiographic techniques and the moderate scores of dental practitioners in Bushehr, it is necessary to place great emphasis on instructions in this regard.

Dental fear is common in children. Many factors affect the severity of this kind of fear. Hospitalization increases children’s dental fears. The aim of this study was to evaluate the effect of the type of hospitalization on children’s dental fear. In this cross-sectional study, 153 children were placed in three equal groups, with a history of hospitalization, with a history of major surgery and a control group without any history of hospitalization and surgery. The children’s dental fear was evaluated with Children’s Fear Survey Schedule-Dental Subscale (CFSS-DS) questionnaire. Data was analyzed with chi-squared and Kruskal-Wallis tests and one-way ANOVA (α = 0.05). The means of dental fear based on CFSS-DS score were higher in hospitalization and surgery groups in comparison with the control group (p value < 0.001). Dental fear score in hospitalization group was 37.4 and higher than the two other groups. Fear from injection and dyspnea and use of dental drills were the most common causes of fear, in descending order, in the groups under study. Hospitalization and surgery increase children’s fear of dental procedures. Dental fear in children with hospitalization in internal wards is more than the other groups, which might be attributed to frequent diagnostic and therapeutic procedures during the hospitalization period.

The number of radiographies taken from patients has increased in recent years. On the other hand, the radiographic images prescribed for patients have not been evaluated in the country. The aim of the present study was to determine the type of radiographic images prescribed by general dental practitioners and specialists in patients under health insurance policy coverage, referring to the oral and maxillofacial radiology centers in Isfahan in 2010. In this descriptive cross-sectional study, 2400 prescribed dental radiographs were randomly selected from the archives of Treatment Services Organization. The data of the prescriptions including the dentists’ gender and specialty field, patients’ age and gender or radiographic image type were extracted and statistically analyzed by chi-squared and linear regression tests (α = 0.05). Most of the radiographic techniques evaluated had been requested by endodontists (408; 17.0%), oral surgeons (404, 16.8%) and orthodontists (362, 15.1%) while 348 (14.5%) belonged to general practitioiners and the rest had been requested by other specialists. Of all the radiographic techniques requested, 47.5% (1141 cases) were bitewing and periapical, 44.3% (1064 cases) were panoramic views, 7.0% (169 cases) were cephalograms and the rest were other types. A total of 65.4% (1569) of the radiographic images had been prescribed for females and 34.6% (831) for males. Bitewing, periapical and panoramic radiographic techniques had the highest request rates in descending order. Endodontists, oral surgeons and orthodontists had the highest request rates. Key words:

Age estimation plays a critical role in pediatric endocrinology, orthodontics, pediatric dentistry, archaeology, etc. The aim of this study was to evaluate the accuracy of dental age estimation in 5‒17 year-old children and adolescents in Kerman using Demirjian method.

This retrospective cross-sectional study was carried out on 350 panoramic radiographs of 224 girls and 126 boys, referring to Kerman dental clinics. Simple sampling method was used. Based on Demirjian method two dental radiologists calculated the dental maturity score (DMS) by assessing the seven left mandibular teeth and estimated the dental age for each case. The chronologic age of each patient was obtained from demographic data. Finally, the correlation between estimated dental age and chronologic age was determined by Pearson’s correlation coefficient and paired t-test using SPSS statistical software (α = 0.05).

Mean dental age in all the subjects was estimated 0.11 year less than the chronologic age. Pearson’s correlation coefficient between estimated and chronological ages was 0.95, indicating statistical significance (p value < 0.001). In addition, there was no significant difference between estimated and chronological ages (p value = 0.15).

Based on the results of the present study, Demirjian method is sufficiently accurate to estimate dental age of children in Kerman is and can be used acceptably.

Self-esteem is an important concept used in psychology to reflect a person's overall appraisal of his or her own value. The present study aimed to assess the relationship between self-esteem and oral hygiene behaviors among student of Isfahan University of Medical Sciences (IUMS). In this descriptive-analytical study a stratified sampling procedure was used to select 320 students from 7 faculties of IUMS. In the second stage, the subjects were randomly selected from each faculty to participate in the study. A questionnaire was used to collect demographic data and data on oral hygiene behaviors. Self-esteem was assessed by the Rosenberg Self-Esteem Scale. Mann-Whitney test, Spearman’s correlation coefficient and descriptive statistical methods were used by SPSS software for data analysis. A total of 63.5% of the subjects were female and 36.5% were male. Mean score of self-esteem in the participants was 20.05. Self-esteem score had a significantly positive correlation with economic status (p value < 0.05). The total score of oral hygiene behaviors in female students (20.86 ± 3.58) was significantly higher than that in male students (19.32 ± 4.02) (p value = 0.012). Tooth brushing frequency, use of dental floss, fluoride consumption, dental checkup frequency and also absence of oral malodor and absence of untreated dental caries were significantly associated with higher self-esteem scores (p value < 0.05). Self-esteem as a common psychological factor is correlated with oral hygiene behaviors. Promoting self-esteem could help people improve oral hygiene behaviors.Key words:

During the past decade, attention to oral health-related quality of life has greatly increased. This study was designed to evaluate the effect of dental treatment under general anesthesia on the quality of life and dental fears in 2‒5 year-old children. The other aim of this study was to explore the effect of dental fears on oral health-related quality of life in children. This descriptive-analytical study was carried out on sixty-five 2‒5 year-old healthy children referring to the operating room of Isfahan Faculty of Dentistry for dental treatment under general anesthesia. ECOHIS (Early Childhood Oral Health Impact Scale) and CFSS-DS (Children’s Fear Survey Schedule– Dental Subscale) questionnaires were used to assess the oral health-related quality of life and dental fears. The questionnaires were completed by parents before and after the dental procedures. Paired-sample t-test and Spearman’s and Pearson’s tests were used for data analysis at a confidence interval of 0.95. Oral health-related quality of life significantly improved after dental treatment under general anesthesia (p value < 0.05). Mean scores before and after were 42.78 and 24.56, respectively, with statistically significant differences. In addition, the mean score of dental fear decreased from 46.29 to 42.20, which was statistically significant (p value < 0.001). Dental treatment under general anesthesia can significantly improve oral health-related quality of life and decrease dental fears in children.

Composite resin restorations have the advantage of restoring the strength of lost tooth structures, which is affected by the technique in which composite resins are used. The aim of this in vitro study was to compare the effect of two restorative techniques with composite resin and enamel and dentin bonding agents on fracture resistance of restored teeth. In the present in vitro study fifty extracted human maxillary premolars were divided into five groups, mounted in acrylic resin and restored as follows after MOD cavities were prepared: group 1: composite resin inlay restoration; group 2: unprepared teeth as controls; group 3: etched enamel and direct composite resin restoration with enamel bonding agents; group 4: prepared but un-restored teeth; group 5: etched enamel, DBA application and composite resin restoration. The samples were prepared and subjected to a compressive force. Data was analyzed using one-way ANOVA; t-test was used for two-by-two comparisons (α = 0.05). The mean fracture resistance values in kgf and standard deviations were 87 (23.16), 142 (53.77), 60.87 (11.52), 41.12 (12.08) and 91.5 (23.60) in groups 1, 2, 3, 4, and 5, respectively, with statistically significant differences between groups 2, 3 and 4 (p value < 0.05). There were no significant differences between groups 1 and 5 (p value > 0.05). The results showed that prepared but un-restored teeth were less fracture resistant than restored teeth. No significant differences were noted in fracture resistance between teeth restored with composite inlay (group 1) and etching the enamel and application of DBA and composite resin (group 5), although both techniques increased fracture resistance. Restoration of prepared teeth with bonded composite resin increased fracture resistance.

Storage time influences some characteristics of irreversible hydrocolloid impression material. The aim of this study was to evaluate the effect of storage time on dimensional changes of alginate irreversible hydrocolloid impression material. In this experimental study, a metal pattern was used with two abutments for a 3-unit bridge. Thirty alginate impressions with standard water-to-powder ratios were provided. The impressions were poured after 15, 60 and 240 minutes with stone gypsum within 10 seconds and the casts were removed after 45 minutes. Then the diameter and height of small and large dies and external distance between the two dies were measured three times by means of digital calipers and the mean values were reported. One-way ANOVA and independent sample t-test were used for data analysis (α = 0.05). The diameter of the large die and the height of the small die exhibited statistically significant differences between 15- and 60-minute time intervals (p value ≤ 0.001 and p value ≤ 0.01, respectively). Comparison of dimensions between 15- and 240-minute time intervals revealed significant differences in the heights of large and small dies (p value ≤ 0.001 and p value ≤ 0.026, respectively). There were no significant differences between 60- and 240-minute intervals in any of the dimensions. Under the limitations of the present study increasing storage time from 15 to 60 minutes led to dimensional instability only in the height of small die, with no effect on other dimensions.

Intravenous conscious sedation is widely used to control anxiety and increase patient tolerance during implant surgeries. Patients experience various sensations due to the use of different medications. In this study, patients’ sensations during conscious sedation were evaluated with the use of four IV sedation regimes to determine the best protocol. In this double-blind randomized clinical trial, 112 patients who were candidates for dental implants were evaluated in four groups: Midazolam, Midazolam/Fentanyl, Midazolam/Acetaminophen and Midazolam/Ketamine. At the end of recovery they were asked about their sensations during surgery. Data were analyzed with Pearson’s, chi-squared, Mann-Whitney and Kruskal-Wallis tests and ANOVA (α = 0.05). Pearson’s and chi-squared tests did not reveal any significant differences between the groups in relation to age, sex, and educational status; ANOVA did not show any differences between the groups in relation to duration of recovery and surgery and the dose of Midazolam used. Kruskal-Wallis test revealed significant differences in pleasant feelings between the four groups (p value < 0.001); Mann-Whitney test did not show any significant differences in pleasant sensations between the Midazolam and Midazolam/Ketamine groups (p value = 0.084). However, frequency of pleasant sensation was significantly higher in the Midazolam/Fentanyl group compared to that in the Midazolam group (p value = 0.008). Frequency of pleasant sensation was significantly higher in the Midazolam/Acetaminophen group compared to that in the Midazolam/Ketamine group (p value = 0.001). Kruskal-Wallis did not reveal any significant differences in pleasant sensations between the four groups (p value = 0.211). Based on the results of the present study, combined use of analgesics and sedatives gives rise to good sensations in patients during surgery and increases sedation efficacy and patient cooperation and satisfaction with the sedation procedure.

The success of endodontic treatment depends on the method and quality of cleaning, disinfection and three-dimensional sealing of the root canal. The smear layer can play an important role in the success or failure of endodontic treatment. There is controversy over the presence or removal of the smear layer in relation to the success or failure of endodontic treatment. This study used standard methods of endodontic treatment and whole human saliva to evaluate the effect of the smear layer on salivary bacterial leakage in endodontically treated teeth.

In this in vitro study, 48 human single- and multiple-rooted teeth were randomly divided into two experimental groups of 20 and two negative and positive control groups of 4 teeth. After access cavity preparation the root canals were prepared with crown-down technique and irrigated with 10 mL of 5.25% sodium hypochlorite solution. The canals in one group were irrigated with 17% EDTA and 5.25% sodium hypochlorite to remove the smear layer and in the other only with 5.25% sodium hypochlorite to leave the smear layer in place. Then the teeth were sterilized by autoclave and obturated with gutta-percha sterilized with ethylene oxide and Tubliseal sealer under aseptic conditions. Two mL of human saliva were collected from two persons and injected into the coronal portion of the samples, which was repeated for four months. Leakage of the samples was examined twice daily. Data was analyzed with chi-squared test at a confidence interval of 95%.

Presence or absence of the smear layer had no significant effect on salivary bacterial leakage of different root canals filled with gutta-percha and Tubliseal sealer (p value = 0.515), although the number of cases with contamination and leakage of saliva in the group with the smear layer (55%) was more than that in the group without the smear layer (44%).

The results showed no significant effect of the smear layer on coronal leakage of human saliva into obturated canals.

Dental radiographs are darkened in some cases due to overexposure, high concentration of developing solution etc. The aim of this study was to evaluate the effect of various undiluted fixing solutions on decreasing the density of dark radiographs. In this analytical cross-sectional study, 95 periapical radiographs were taken from the first mandibular molar of a dry skull. One film was developed under optimal conditions and considered as gold standard or the positive control; 93 films were overexposed to enter the study. The last film was overexposed, was not included in the study and was considered the negative control to compare the effect of fixing agent. All the radiographs were processed automatically under the same conditions. Then the overexposed radiographs were divided into three equal groups of 31 radiographs. Each set was immersed in different undiluted fixing solutions, including Champion, Cronex, and Teif Saz. Finally, the densities of radiographic films were assessed objectively by a densitometer and subjectively by obtaining questionnaires from observing dental practitioners. Data was analyzed by ANOVA and Duncan test (α = 0.05). The densities of all the radiographs had significantly decreased after immersion in undiluted fixing agents. Furthermore, improvements in diagnostic quality of the darkened radiographs were significant due to the effect of undiluted fixing agents (p value < 0.001). Generally, the undiluted fixing solution is a suitable agent to decrease the density and restore the diagnostic quality to dark radiographs, preventing re-exposure of patients and avoiding extra costs.

Prediction of mesiodistal widths of unerupted permanent teeth is an important aspect of space analysis during the mixed dentition period. The aim of the present study was to determine equations that can estimate the mesiodistal widths of unerupted canines and premolars of both arches in the early mixed dentition period using total widths of mandibular incisors. In this observational cross-sectional study, 100 children (50 girls and 50 boys) aged 12‒13 years in the guidance schools of Isfahan were randomly selected. The subjects had no developmental or occlusion anomalies, with no visible malformations, caries or abrasions in their teeth. After impression and preparation of dental casts, mesiodistal dimensions of all the permanent mandibular incisors, canines, and first and second premolars were measured in both arches using a Vernier caliper. Pearson's correlation coefficient, linear regression and independent t-test were applied for statistical analysis (α = 0.05). Equations for this research were as follows: U = 9.295+0.549 (M), L = 6.622+0.633 (M) for girls and U = 13.4+0.38 (M), L = 11.058+0.455 (M) for boys, in which M is the total mesiodistal crown diameter of lower incisors, and U and L are the total mesiodistal crown diameters of canines and premolars in the maxilla and mandible, respectively. Statistically significant differences were observed in the total mesiodistal widths of canines and premolars between arches and genders. Correlation coefficients for the upper and lower arches were 0.76 and 0.83 in females, and 0.63 and 0.65 in males, respectively. Under the limitations of the present study, it can be concluded that it is possible to use regression equations to predict the mesiodistal widths of canines and premolars by measuring the total widths of permanent mandibular incisors.

Triamcinolone has been introduced as the treatment of choice in symptomatic treatment of oral aphthous ulcers in the medical literature. One of the major challenges in drug therapy all over the world is how to deliver the drug to target tissues, and how to best deliver minimal amounts of the drug to the injured organ. The aim of this pilot study was to determine minimum dose of the required drug effective on the oral minor aphthous ulcers and evaluate its effectiveness. In this double-blind pilot clinical trial, a new form of muccoadhesive with the dual aim of dressing of and concentration of the drug on the aphthous ulcers was designed and manufactured by adding triamcinolone to muccoadhesive base. The drug was applied to 40 patients with no systemic conditions or previous drug therapy. Only 23 of the patients cooperated during the whole trial and could provide documented data. Fourteen patients received the drug and 9 received a placebo. Pain severity was evaluated by VAS scale and maximum diameters of ulcers were measured in millimeter. Data were analyzed by SPSS software and Mann-Whitney test (α=0.05). In patients who received the drug the diameter (p value = 0.026) and pain severity (p value = 0.043) were significantly less during the second appointment in comparison with the patients receiving placebo. However, during the third appointment there were no significant differences between the two groups (p value < 0.05). According to the results of this pilot clinical trial, addition of triamcinolone to the base of muccoadhesive has a significant effect on diminishing pain severity and diameter of oral ulcers in the short term in comparison to placebo and this approach can effectively be used to decrease pain severity accelerate ulcer healing.

Oral health includes healthy mouth and its healthy tissues, which prepares us for daily activities without discomfort and dissatisfaction. In this research, agreement level between parents and children aged 8-10 in rating child oral health-related quality of life was studied in Isfahan. In this descriptive, analytical and cross-sectional study 138 pairs of parents and children aged 8-10 were selected with simple random sampling technique from elementary schools in Isfahan and were asked to complete the relevant questionnaires. The questionnaires evaluated quality of life in four fields of oral signs, functional deficits, and emotional and social health. In order to evaluate child-parent agreement, intra-correlation coefficient (ICC), Pearson’s correlation coefficient, Spearman’s correlation coefficient and intra-class correlation coefficient (ICC) were used. The agreements between PPQ8-10 (parent perception questionnaire), CPQ8-10 (child perception questionnaire) and the related fields were 0.63, -0.28, and -0.67. The highest agreement level (ICC = 0.69) was related to functional deficits (good), followed by oral signs (ICC = 0.56) (moderate) and emotional health (ICC = 0.31) (mild). The least agreement level was related to social health (ICC = 0.08). Pearson's test showed significant correlations between CPQ8-10 and PPQ8-10 (r = 0.46) (p value < 0.01). Although parents, especially mothers, may be used as proxies for their children in relation to quality of life and related fields, the views of both should be obtained in order to fully represent child oral health-related quality of life issues.

Radiography has an important role in the diagnosis of diseases. Professional responsibility necessitates that dental practitioners have adequate and sound knowledge about the techniques to minimize the patient dose. The aim of this study was to evaluate the awareness of dental practitioners in Isfahan about how to prescribe correct radiographs in 2010-2011. In this descriptive/cross-sectional study data was collected by distributing questionnaires among 400 dental practitioners in Isfahan. The questionnaire consisted of three parts, including a description of various radiographic techniques in the form of awareness questions. Awareness of dental practitioners was evaluated in 25 different fields, including correct prescription of radiographs. Data was analyzed and compared between the fields under study by one-way ANOVA and independent t-test (p value < 0.05). Of the 400 dental practitioners taking part in the study, 222 (55.5%) were males and 178 (44.5%) were females, with no statistically significant differences in awareness between them (p value = 0.094). The mean awareness grades of dental practitioners with job experiences less than 5 years and more than 5 years were 11.76 ± 2.58 and 10.4 ± 2.74, respectively, with statistically significant differences (p value > 0.001). The results of this study showed that the awareness of dental practitioners in Isfahan about correct radiographic techniques is less than the acceptable level. Therefore, it is necessary to increase their knowledge and awareness by continuous education programs.

Based on data available, about 10% of people have severe dental anxiety. There are several methods to control dental anxiety, the use of which entails knowledge on behalf of the dental practitioners and appropriate equipment. This study evaluated knowledge of dental practitioners about dental anxiety control methods. In this study descriptive study, 249 dental practitioners in Isfahan were selected using simple sampling method and given a questionnaire consisting of 20 questions about pharmacological methods to control dental anxiety in patients. Data was analyzed with SPSS software using ANOVA at a significance level of 0.95. Knowledge scores were reported from 0 to 20. Knowledge scores for inhalation sedation, oral sedation and general anesthesia were 12.65 ± 3.31, 13 ± 2.84, and 17.91 ± 6.12, respectively. Mean of dental knowledge scores of dentists in relation to pharmacological sedation techniques was above 12, indicating proper knowledge level of dental practitioners. ANOVA did not reveal any significant differences in knowledge level means between different age groups in relation to general anesthesia (p value = 0.217). However, there were significant differences in the knowledge means between various age groups in relation to inhalation (p value = 0.036) and oral sedation (p value = 0.035) techniques. Under the limitations of this study the knowledge of dentists about pharmacological methods of controlling patient anxiety in dentistry was good but these methods are not widely used due to lack of background support. Given the importance of such measures, it is necessary to increase the knowledge of the community about these techniques.

Measuring the antero-posterior jaw relationship has an important role in the diagnosis and treatment planning in orthodontics. Common linear and angular measurements to evaluate sagittal jaw relationship, including ANB angle and Wits index are not very accurate because various factors influence them. The aim of this study was to evaluate µ angle range in 6-17 year-old students with normal occlusal relationships in Isfahan. In this descriptive-analytical study, the files in the archives of the Orthodontics Department, Isfahan Faculty of Dentistry, were evaluated and 218 cephalometric radiographs from the files of patients with no orthodontic treatment were selected; the subjects were considered to have normal occlusal relationships based on 13 criteria. The subjects were divided into 5 age groups. After tracing the cephalometric radiographs, ANB angle, Wits index and µ angle (the angle produced by the AB line intersecting the line perpendicular from A to mandibular plane) were measured and the means, standard deviations and changes in the ranges of these angles were determined. Data was analyzed by t-test, ANOVA and Pearson’s and Spearman’s correlation coefficients using SPSS software (α=0.05). The results showed a mean of 17.34 ± 3.74º for β angle with a range of 8-27º. T-test showed significant differences in μ angle between males and females (p value = 0.021). In addition there was no significant relationship between this angle and age (p value > 0.05). There was an inverse and significant relationship between AB angle and Wits index. It was concluded that µ angle is accurate in evaluating antero-posterior jaw relationship and can be used as a valuable index in evaluations.

Recognition of psychological factors plays an important role in determination of orthodontic treatment needs as well as achieving a successful treatment. The aim of this study was to investigate the relationship between self-concept, dentofacial body image, subjective orthodontic treatment needs and professionally determined needs for orthodontic treatment among a group of university students.

In this cross-sectional study, 164 students of Isfahan Faculty of Nursing and Midwifery were studied based on a simple sampling procedure. Data were collected using a standardized questionnaire consisting of 40 questions, including 3 parts for measurement of self-concept, dentofacial body image and self-perceived treatment need. Professionally determined orthodontic need was assessed using IOTN by two orthodontists. Data was analyzed using SPSS 11. Statistical methods for standardization of questionnaire, Cronbach's alpha, Student’s t-test and Spearman’s correlation were used at a significance level of 0.05.

Statistically significant correlations were seen between participant's self-concept, dentofacial body image, subjective orthodontic need and the professionally determined orthodontic need, with Spearman’s correlation coefficients of -0.16, 0.19 and -0.036, respectively (p value < 0.05).

The majority of the students were satisfied with their teeth alignment and the more satisfied they were, the higher self-concept they had, with lower demand for orthodontic treatment. Moreover, the orthodontic needs determined by orthodontists were less among students with high self-concept.

Incomplete polymerization of composite resins has unfavorable effects on the clinical function and the esthetics of the restoration. The aim of this study was to determine the relationship between the light intensity of light-curing units in the Department of Operative Dentistry of Isfahan Faculty of Dentistry and the curing depth according to ISO 4049 standards and also to compare the primary and final light densities of the units. In this in vitro study, first the light intensities of 9 light-curing units of the Department of Operative Dentistry were measured by a radiometer. According to ISO 4049 if the intensity of the light-curing unit was higher than 200 mW/cm2, the unit was used to cure five samples of Z100 composite resin. A total of 7 units were used to cure 35 specimens. The exposure time of the units with 200-300 mW/cm2 light intensity was twice those of units with over 300 mW/cm2. The uncured composite resins were removed by scraping and half of the least remaining composite resin thickness was recorded as the curing depth. Finally the light intensity of each unit was measured again. Data was analyzed with SPSS using t-test and correlation coefficient (α = 0.05). The light intensity of light-curing units was 40‒620 mW/cm2: four units with above 300 mW/cm2; three with 200-300 mW/cm2 and two with less than 200 mW/cm2. Only two light-curing units exhibited significant differences between primary and final light intensities (p value < 0.001). The correlation coefficient between the light intensity and curing depth was 0.58. All the curing depths were within the ranges of ISO 4049 standards regardless of duration of exposure. All the light-curing units with a light intensity of more than 200 mW/cm2 had achieved the necessary curing depth specified by ISO 4049 and there was a positive correlation between light intensity and curing depth.

Advent of digital imaging technology revolutionized radiology science, one aspect of which is indirect digital imaging technique. In this technique scanners or digital cameras are used to digitize radiographs. The aim of this research was to compare diagnostic quality of conventional periapical radiographs digitized with scanners and cameras. In this in vitro study 40 radiographs were digitized with two scanners and two cameras in the six following 3- and 5-Megapixel Fuji digital cameras, 5 -MP Canon digital camera, 450 dot per inch and 600 dpi Epson scanners and 600 dpi HP scanners. A total of 240 images were prepared. Four specialists and general dental practitioners were asked to observe 4 anatomic landmarks (periodontal ligament, root apex, lamina dura and cancellous bone) on the conventional and digitized radiographs, score the qualities from 1 to 3 and record them in a check list. SPSS software was used for data analysis by ANOVA and Friedman and Wilcoxon tests.(α = 0.05) Analog radiographs received higher scores compared to the two digitization techniques (p value < 0.001), with higher diagnostic value scores for the images of the digital cameras (p value < 0.001). Analog images were superior to digital images in the present study. It appears the habitual and repeated visualization of conventional radiographs and the quality and age of the cameras, scanners and monitors used in this study all had an influence on the results.

Complete adhesion of the impression materials to trays is important to prevent impression materials from being pulled away from trays during removed from the mouth and to ensure that the direction of polymerization shrinkage will be towards the tray. The aim of this study was to evaluate the effects of two retention features of custom trays (adhesive vs holes) on the dimensional accuracy of master casts made from two alginate impression materials. In this in vitro study, 88 impressions were made in eight groups (n=11) of a stainless steel model with three index studs and then poured with a Type III dental stone. Three variables were considered: type of irreversible hydrocolloid material, retentive perforations in impression trays and application of a spray-on tray adhesive. The distances between the reproduced index studs were measured to ±0.01 mm with a digital caliper. Kruskal-Wallis and Mann-Whitney tests, ANOVA and t-test were used for data analysis (α=0.05). ANOVA revealed significant differences between the groups only in the vertical dimension (p value = 0.001). There were significant differences between the two tray and alginate types only in the vertical dimension (p value < 0.001 and p value = 0.011). There were no significant differences between the adhesive and non-adhesive groups. There were significant differences in the means of all the dimensions of the two trays as compared with master model. Iralgin alginate group exhibited significant differences in the means of all the three variables compared to the main cast; Xantalgin alginate exhibited differences only in the longitudinal dimension. Non-adhesive group exhibited significant differences in all the three dimensions but the adhesive group did not reveal significant differences only in the vertical dimension. Perforated tray, Xantalgin alginate and use of adhesive produced more accurate casts in all the dimensions compared to corresponding groups. In cases in which an adhesive is not used dimensional accuracy will improve via perforated trays. By using an adhesive with non-perforated tray, Xantalgin alginate has more accurate results; use of an adhesive along with perforated trays produces better results with Iralgin alginate, but no improvements are achieved with Xantalgin.

Early Childhood Oral Health Impact Scale (ECOHIS) is a measure which can assess oral health-related quality of life (OHRQoL). The scale questionnaire has already been translated into Farsi and its validity and reliability have been tested. This study aimed to investigate the sensitivity and responsiveness of the Farsi version of the Early Childhood Oral Health Impact Scale (F-ECOHIS) to routine dental treatments in preschool children. In the descriptive-analytical study a simple sampling procedure was carried out to select 143 parents of 2-5 year-old children, attending a dental clinic, to complete F-ECOHIS prior to and 1 month after their child’s routine dental treatment. In addition, the parents rated the changes they expect in their child's oral health condition, compared to pre-treatment period, based on a global transition scale. Sensitivity of the measure was assessed by determining changes in ECOHIS scores; responsiveness was assessed by investigating whether the observed clinical changes were consistent with the changes expected, in terms of the changes observed in life quality and effect size. Data were analyzed by Wilcoxon’s signed-rank test. Following routine dental treatment, there were significant changes in F-ECOHIS scores before and after treatment (p value = 0.001). Means and standard deviations of questionnaire scores before and after treatment were (22.3 ± 9.4) and (13.2 ± 6.3), respectively. Life quality gradient was consistent with changes of ECOHIS scores in relation to the quality of life expected and assessed by parents, supporting the responsiveness of the measure. The F-ECOHIS is sensitive and responsive to routine dental treatments in preschool children.

Road accidents, with motorcycle accidents comprising a major fraction of them, are the second most important cause of death in Iran. This study aimed to evaluate the frequency of head and face injuries in motorcyclists who had an accident and to find out relationship between helmet use and frequency of these injuries and hospitalization costs of these accidents. Data in this retrospective descriptive-analytical study was collected from "Form 92", a registration form of motorcyclists who had accidents and were hospitalised in the Azahra Hospital in 2010, including hospitalization period, treatment costs, severity of injuries, and time of the accident (n = 1626). Of the injured motorcyclists registered in Form 92 during the last three months of the year, 125 cases were randomly selected and interviewed by phone in relation to wearing a helmet during the accident. Data was analyzed by descreptive tests and Phi & Cramer's correlation coefficient using SPSS 11.5 (α = 0.05). Accidents by motorcycle comprised 31% of all the registered motor vehicle accidents. The frequency of motocycle accidents was higher in October and among 21-25 year-olds. The mean period of hospitalization was 4.3 days and the mean of hospital costs was about 9,000,000 Rials. The frequency of head and face injuries was 51% among all the injured motorcyclists, with 22% among those wearing a crash helmet and 78% among those not wearing a crash helmet (r = 0.267, p value = 0.009). A total of 35% of motorcyclists reported wearing crash helmets. Based on the results of the present study, motorcycle accidents impose a lot of costs on peple and the community. Use of a crash helmet can significantly reduce the frequency of head and face injuries more than three folds.

Fear and anxiety due to the dental treatment decrease cooperation of the child during the procedure. Since the majority of parents are willing to accompany their children in the operating room, the present study was carried out to evaluate the effect of parent's presence on fear and cooperation of children aged 4-6 years, referring to the Department of Pediatric Dentistry in Isfahan Faculty of Dentistry. This cross-sectional study was carried out on fifty systemically and mentally healthy 4-6 year-old children referring to Isfahan Faculty of Dentistry, with no previous dental experience. The subjects were randomly divided into two groups. In the first group, 25 subjects were accompanied by their parents during the whole procedure. In the second group, the subjects were not accompanied by anyone. During the treatment, the cooperation rate of each child was assessed by Franckle index and after the treatment, the fear score of each child was measured with the CFSS-DS questionnaire (child fear schedule survey - dental subscale). T-test and Mann-Whitney were used to compare dental fear and cooperation between the two groups, respectively. Spearman's correlation coefficient was used to assessing fear scores and cooperation rates (α = 0.05). The means of fear scores in the presence and absence of parents were 26.60 ± 6.40 and 28.80 ± 10.61, respectively. There were no significant differences in fear rates and cooperation levels of children between the two groups based on CFSS-DS (p value = 0.37 and 0.79, respectively). There was a significant but inverse correlation between fear scores and cooperation levels (r = 0.783, p value < 0.001). Based on the results of the present study, parental presence or absence does not affect fear and cooperation of 4-6 year-old children during dental procedures.

The aim of this study was to evaluate the specificity and sensitivity of last-year dental student's diagnostic skills for proximal caries on bitewing radiographs in Isfahan Faculty of Dentistry. In this study, 50 intact and carious molar and premolar teeth were mounted in wax and underwent bitewing radiographic techniques. Then 40 volunteer dental students from Isfahan Faculty of Dentistry categorized proximal carious lesions in special questionnaires. Subsequently the teeth were sectioned in a mesiodistal direction at the center of the contact area and evaluated clinically under a microscope at ×5. The results reported by the students were compared with the results of microscopic evaluation (gold standard). Statistical formulas were used to determine specificity, sensitivity and false positive and negative results. This study showed that sensitivity of intact and carious surfaces were 64.8% and 62.2%, respectively. Furthermore, sensitivity of enamel and dentin caries were 55.6% and 69.6%, respectively. The results showed that last-year dental students had a high rate of incorrect diagnosis in comparison with the gold standard. Therefore, more attention should be paid to instructing dental students.

Tooth sizes have been reported to be different in different races. Comparison of sizes of primary and permanent teeth, relationship between mesiodistal widths of deciduous and permanent teeth and diagnosis of discrepancies are clinically important. Awareness of the mean sizes of teeth helps predict the space necessary for tooth eruption in space analysis. In this analytical cross-sectional study, the subjects were selected from patients referring to various departments of Faculty of Dentistry, Isfahan University of Medical Sciences, in two groups of 3-5 and 13-18 years of age. Study casts were provided for all the subjects and the mesiodistal widths of the teeth on the left side were measured by a precision caliper. Data was analyzed by ANOVA and independent t-test (α = 0.05). The mean mesiodistal widths of primary and permanent teeth in both jaws were measured. Gender dimorphism had no role as a factor determining mesiodistal width of the crown between boys and girls. The central and lateral maxillary incisors, canines and second mandibular molars were significantly larger in boys compared to girls (p value < 0.05) and maxillary first premolars were significantly greater in girls compared to boys (p value < 0.05). Mesiodistal mean sizes of primary teeth were bigger than those of American whites, but smaller than the Japanese. Like many other studies, mesiodistal mean sizes of teeth in boys were greater compared to girls. Different results in different studies might be attributed to the type of the study (cross-sectional vs long-term), indexes used, races, measuring techniques, the methods employed etc.

Radiography is a commonly used paraclinical technique to diagnose and cure orodental diseases. Due to possible dangers of x-rays, it is very important for dental practitioners to be familiar with methods to protect themselves and their patients against x-rays. The aim of the present study was to evaluate awareness, performance and attitudes of general dental practitioners in Yazd about ionizing radiation and protection methods. In this descriptive‒analytical study data was collected by one standard questionnaire filled by 92 general dental practitioners. Data was analyzed by t-test and Pearson’s correlation coefficient using SPSS 15 statistical software (α=0.05). The results showed that the average scores of awareness, attitude and performance of general dental practitioners were 8.57, 35.84 and 7.90, respectively. There were direct relationships between job experience and awareness (r = 0.532, p value = 0.00), job experience and performance (r = 0.339, p value = 0.01), and awareness and performance (r = 0.367, p value < 0.001). Due to poor awareness and performance of dental practitioners in relation to protective measures against ionizing radiation, more educational classes and long-term planning are necessary to improve the situation. Since conventional educational methods have not been able to improve the situation, new educational techniques are necessary.

Observance of ethical codes in dental research has received little attention. This research aims to evaluate observance of national research ethics codes in research proceedings of doctoral dissertations in the Faculty of Dentistry, Islamic Azad University, Khorasgan Branch in 2004-2009. This descriptive-analytical research was conducted on 200 doctoral dissertations. National ethics codes in medical research were evaluated by two researchers. Data was recorded in specially designed forms and analyzed by descriptive statistical tests. In all the dissertations – human and non-human research studies – all the ethics codes in relation to confidentiality of data, conformity with cultural and religious principles, and the possibility of side effects for the subjects, had been observed. In relation to human studies 89 dissertations lacked informed written consent forms, with oral consent taken in 83% of cases. In only 14 cases (15.7%) of the participants were aware of their right to exclude themselves whenever they wished. In laboratory research dissertations (111 cases) in only 47% of cases all the ethics codes had been observed. All the sixteen medical ethics codes in human research had not been observed in any of the research protocols; in laboratory research, almost half of the protocols had observed scientific ethics principles (5 codes), which might be attributed to a lack of importance of registration of ethics codes in research protocols despite the fact that researchers usually observe them in dissertation protocols.Key words:

Periodontitis, a prevalent oral disease, has been associated with several systemic conditions, including lipid metabolism disturbances. The aim of this study was to evaluate the effect of periodontal treatment on decreasing plasma lipids levels. In this case/control study sera were collected from 25 adult periodontitis patients and 25 healthy control subjects referring to the Faculty of Dentistry in Isfahan. Plaque indexes, pocket depths, bleeding on probing (BOP), attachment loss (AL) and serum lipid levels (cholesterol, triglyceride, HDL, LDL) were recorded in both groups. Periodontal treatment was carried out only for the test group patients. Six weeks after periodontal treatment, serum lipid levels were measured again in both groups and the results were compared with the initial values (α=0.05). The serum levels of triglyceride, cholesterol, HDL, LDL in the test group before treatment were 156/96,184/64, 49/20, 116/68 mg/dL, respectively, with 121/36, 157/56, 47/85, 114/36, respectively, after treatment. The decreases in triglyceride and cholesterol serum levels were significant but decreases in HDL and LDL levels were not significant. The results of this study indicate that there is a significant relationship between periodontal treatment and a decrease in serum lipid levels. The possible mechanism is the relationship between bacterial endotoxins and induction of proinflammatory cytokines, resulting in changes in the metabolism of lipids, which gives rise to hyperlipidemia.

Communication and professional ethics competencies are crucial in providing dental health care. Research has shown that teaching these competencies and patient rights to dental students is necessary. The aim of this study was to evaluate attitudes of under- and post-graduate dental students of Isfahan Faculty of Dentistry in relation to communication skills, professional ethics and patient rights.

Sixty-one under- and post-graduate dental students were randomly selected for the purpose of this study, who voluntarily completed a relevant questionaire. Psychometric characteristics, face validity and internal consistency of the questionaire content were tested in a pilot study so that the questionnaire could be revised. Data was analyzed by SPSS 11.5 using t-test, one-way ANOVA, and Kruskal-Wallis and Mann-Whitney U tests (α=0.05).

Cronbach’s alpha cofficient for communication and professional ethics was 0.969, which was considered favorable. Mean and standard deviation of communication skills and professional ethics competencies in under- and post-graduate dental students were 3.68±0.37 and 4.25±0.37, respectively. Mean scores of these competencies were significantly higher in post-graduate students compared to under-graduate students (p value = 0.03).

The results showed that post-graduate students exhibit higher communication skills and professional ethics competencies in the management of their patients.

Toxicity of dental alloys depends on their composition and element release, which may, in turn, be affected by re-casting of the alloy. The aim of this study was to evaluate the effect of re-casting on the release of elements from Verabond base metal alloy. In this laboratory study Verabond base metal alloy was evaluated. At first cubic wax patterns measuring 11×13×1.4 mm were prepared. Then alloy disks were cast as follows: 100% new alloy; 50% new with 50% re-cast alloy; and 100% re-cast alloy. Each alloy specimen was finished and polished under simulated clinical conditions and sterilized in an autoclave. Each specimen was conditioned in artificial saliva at 37°C for 72 hours. The specimens were retrieved from artificial saliva and release of elements from the alloys was investigated by Atomic Absorption Spectrophotometry. Data was analyzed by one-way ANOVA and a post hoc Tukey test (α = 0.05). ANOVA revealed significant differences between the cast and re-cast Verabond groups; release of titanium, nickel, aluminum and chloride were respectively higher in recast alloys compared to cast alloys (p value < 0.05). The amounts of Be, Mo, Co were not quantified by spectrophotometry due to their low concentrations. Based on the results of the present study, re-casting of alloys significantly increases the release of elements. Therefore, re-casting of alloys should be avoided.

Communication and professional ethics competencies are crucial in providing dental health care. Research has shown that teaching these competencies and patient rights to dental students is necessary. The aim of this study was to evaluate attitudes of under- and post-graduate dental students of Isfahan Faculty of Dentistry in relation to communication skills, professional ethics and patient rights.

Sixty-one under- and post-graduate dental students were randomly selected for the purpose of this study, who voluntarily completed a relevant questionaire. Psychometric characteristics, face validity and internal consistency of the questionaire content were tested in a pilot study so that the questionnaire could be revised. Data was analyzed by SPSS 11.5 using t-test, one-way ANOVA, and Kruskal-Wallis and Mann-Whitney U tests (α=0.05).

Cronbach’s alpha cofficient for communication and professional ethics was 0.969, which was considered favorable. Mean and standard deviation of communication skills and professional ethics competencies in under- and post-graduate dental students were 3.68±0.37 and 4.25±0.37, respectively. Mean scores of these competencies were significantly higher in post-graduate students compared to under-graduate students (p value = 0.03).

The results showed that post-graduate students exhibit higher communication skills and professional ethics competencies in the management of their patients.

Oral health includes healthy mouth and its healthy tissues, which allows for eating, speaking, and social encounters without active disease, discomfort, and dissatisfaction. In this research, validity and reliability of Persian translation of Quality of Life related to oral and dental health questionnaire was studied in children aged 11‒l4 years in Isfahan. In this descriptive, analytical and cross-sectional study the subjects consisted of 128 children aged 11–14 randomly selected from schools in Isfahan. The children completed the Children Perception Questionnaire (CPQ), and then they were examined. DMFT, dmft, molar-incisor hypoplasia (MIH), traumatic dental injuries (TDI) and malocclusion indexes were determined. To study the reliability of CPQ, 60 of these children completed the questionnaire again without dental intervention two weeks later. To understand the relation between the indexes, ANOVA and Spearman’s correlation coefficient were used. In addition, Cronbach’s alpha and interclass correlation coefficient (ICC) were determined (α=0.05). The average score of CPQ was 20.6 with a standard deviation of 16.60, with higher scores in females compared to males. Cronbach’s alpha and ICC were 0.92 and 0.82, respectively. CPQ had an insignificant correlation with DMFT, dmft, TDI, MIH and malocclusion (p value > 0.05). The Farsi version of the questionnaire is valid and reliable for use for Iranian children aged 11‒14 and can be used as a useful tool to assess the effect of oral and dental disorders on quality of life.

Doctoral dissertations are considered one of the most important sources of information and research activities. This study investigated the quality of doctoral dissertations of Isfahan Faculty of Dentistry during 2005‒2009.

In this cross-sectional analytical study one hundred undergraduate and postgraduate dissertations dental students in Faculty of Dentistry were selected by simple random sampling procedure during 2005‒2009. A questionnaire was prepared for data collection, which was filled in qualitatively. The variables evaluated consisted of means of achieving the aims of the study, evaluation of hypotheses, sufficiency of study population size, correct statistical tests, materials and methods, arrangement of the references, preparation of the “discussion’ and “conclusion”, separately for each educational level. Chi-squared test was used for statistical analysis of data with SPSS software.

A total of 52% and 48% of the dissertations were observational and interventional, respectively, with 44% being descriptive. The results showed tha the highest overall evaluation scores belonged to animal studies (100 ± 0.00), the lowest belonged to case-control (84.63 ± 13.61) and descriptive studies 86.7 ± 7.56, respectively. Average MSc (19) and doctoral (81) dissertation evaluation scores were 90.84 ± 8.248 and 88.28 ± 8.872, respectively. A total of 78% and 80% of dissertations achieved their goals and hypotheses, respectively. A total of 97%, 78% and 98% had sufficient population sizes, used appropriate statistical methods and had well written discussions, respectively.

Results showed that the strengths of these dissertations included well written discussions, literature reviews and reference lists. Errors were observed in preparation of hypotheses, aims, statistical analyses, and sample sizes. It appears it is necessary to improve the quality of dissertations by holding classes on research techniques and good writing for students since the dissertations will be finally shared with other researchers in the form of articles.

Qualitative research has an important role in promoting oral health, especially in identification of problems, preparation of scientific hypotheses, and evaluation and identification of individual aspects which have not been fully understood. The aim of this study was to interview patients referring to Shariati dental clinic in Isfahan to determine patients’ views on oral health educational needs in relation to prevention of disease and promotion of oral health. This qualitative research was carried out based on “grounded” theory. Aim-oriented theoretical sampling method was used and sampling was stopped at the saturation point. Data was collected and recorded using in-depth interviews. In general the participants believed that educational films were useful tools to promote oral health. Participant's educational needs were categorized in four main groups: oral health education, proper nutrition, information about fluoride, and education required in order to eliminate false beliefs. Subdivisions were found for each category during the coding process. The participants in this study reported a need for dental educational programs to improve their knowledge on the correct methods to promote oral health, nutrition and the use of fluoride. Oral health educational movies were considered useful tools.

One of the branches of computer science that tries to simulate human intelligence is artificial intelligence. Correct diagnosis of pulp and periapical lesions can prevent various problems and spread of disease. The aim of this study was to use a decision support system (DSS) with a fast and accurate data processing capacity to diagnose and present treatment plan for pulp and periapical lesions in order to have an accurate and rapid access to gold standard results with minimum error.

In the present study on diagnostic research, raw data was collected, revised and approved by professors as the gold standard in order to design the software. Preliminary data was standardized by writing an algorithm and then converted into a flowchart. Next, the programmer started simulation with the Visual C++ Compiler under Windows 7. α and β versions were delivered to professionals in order to fix bugs. Finally, performance evaluation of gold release (final) version was carried out by taking signs of 43 patient samples and transferring them to this version. Statistical analysis of the results was carried out with SPSS 17 at a 95% confidence interval.

The results showed that the overall efficacy of the software was 86.21%; software efficacy scores for periapical diagnosis, treatment plan and periapical diagnosis were 89.66%, 86.21% and 82.76%, respectively.

This software with high data storage and recall details can assist the dental practitioner as a reliable tool in the diagnosis and appropriate endodontic treatment planning.

Knowledge of prevalence and etiologic factors of tooth discoloration can help design strategies for intervention to prevent tooth discoloration. The aim of this study was to determine the prevalence and etiologic factors of tooth discoloration in male high school students in Isfahan. In this cross-sectional study, 384 male students were selected by cluster sampling method. The students were examined by a well-instructed individual. Data was collected and recorded using a questionnaire and then analyzed by descriptive methods in SPSS at a 95% confidence interval. The prevalence of tooth discoloration was 89.9% in male high school students in Isfahan. Relative frequencies of etiologic factors of tooth discoloration consisted of caries, 80.6%; hypoplasia, 18.2%; extrinsic stains, 9.5%; root and crown restorative materials, 4.8%; trauma, 1.3%; tetracycline and smoking, 0.8%; fluorosis, 0.5%; and chlorhexidine mouthwash, 0.3%. No cases of amelogenesis imperfecta, dentinogenesis imperfecta, and drug use by mothers during pregnancy. In this study caries was the most common cause of tooth discoloration. Given the high prevalence of carious lesions, instruction of oral hygiene habits and improving nutrition of the students are recommended.

Considering the positive effect of health education on behavior change and health promotion, this study aimed at evaluating the effect of an educational program about fissure sealant therapy (FST) on behavior of mothers in relation to providing FST for their children. This randomized controlled trial evaluated 180 students with an age range of 6 to 9 years and their mothers in Isfahan. The participants were randomly divided to 3 groups: 2 intervention and one control group. The subjects were included if they had at least one sound first molar and excluded if they had any history of FST. One intervention group received the educational program through an oral presentation supplemented with a pamphlet and the other group was mailed only a pamphlet. The control group did not receive any instruction. After three months, the subject's first molars were clinically examined for the presence of FST. Descriptive analysis and chi-squared test were used for data analysis at 95% confidence interval. After three months, 11.7% of the subjects had FSTs, 66% of which were in the oral presentation group and 34% were in the pamphlet group. There were no teeth with FST in the control group. There were no significant differences between the intervention groups (p value < 0.08); however, there were significant differences between the intervention groups and the control group (p value = 0.001). Educational programs can effectively change the attitudes of mothers and encourage them to provide fissure sealant services for their children.

The quality of panoramic radiographs has a great role in the diagnosis of lesions. The aim of the present study was to evaluate the effect of BMI and the type of the radiographic cassette on the diagnostic quality of panoramic images through evaluation of maxillary sinus periphery, mandibular cortex, tooth enamel and tooth fillings. In this cross-sectional study, 400 patients with an age range of 2-70 years, who required panoramic radiographs, were selected. Type of the cassette used and patients’ weights, heights and ages were recorded before radiography. After processing the images, each anatomical landmark was scored on a 3-point scale. Total quality for each image was defined as the average of these scores for selected landmarks. The overall density of each image (i.e. the overall quality) was also scored. Data were analyzed by Spearman’s correlation coefficient, Mann-Whitney test, t-test and regression test (α=0.05). Spearman’s correlation coefficient revealed a significant correlation between BMI and resolution of the periphery of maxillary sinus and the overall image density (p value < 0.0001). No correlation was found between BMI and resolution of mandibular cortex (p value = 0.7) and tooth crown enamel and fillings (p value = 0.2). Cassette type had no effect on image quality. The results indicated cassette type has no effect on image quality provided other exposure factors are properly chosen. Furthermore, an increase in BMI has no effect on resolution of anatomic landmarks provided that other exposure factors are properly chosen, although it increases image density. It appears panoramic radiographic technique is a useful diagnostic tool, especially for adults.

Emergence agitation is a common clinical phenomenon in children undergoing general anesthesia. Possible predisposing factors are rapid regaining of consciousness in an unfamiliar environment, the type of general anesthesia technique used, the patient’s mood, duration of anesthesia and age. The aim of the present study was to compare the effects of two general anesthetic methods with and without local anesthetics on emergence agitation of children volunteering for general anesthesia in the recovery room. In this prospective single-blind clinical trial, 60 children under 6, who volunteered for general anesthesia, were randomly divided into two groups. All the subjects were anesthetized using the same protocol. During the dental procedure in the study groups, the teeth involved were anesthetized with one lidocaine+epinephrine cartridge using the infiltration technique. The children's emergence agitation was evaluated and compared between the two groups. Data was analyzed with t-test, ANOVA Mann-Whitney test and Spearman’s correlation coefficient (α = 0.05). There were no statistically significant differences in the means of age, in gender and in the number of treatment procedures between the two groups. Emergence agitation scores in the local anesthesia group at 15- and 30-minute intervals were 9.6±3.92 and 8±2.58, respectively, demonstrating a significantly higher rates compared to the other group (p value = 0.013 and p value = 0.014). However, there were no statistically significant differences at 45- and 60-minute intervals between the two groups (p value = 0.872 and p value = 0.048). Based on the results it was concluded injection of a local anesthetic reduces emergence agitation in children undergoing general anesthesia. Therefore, it is recommended to use this technique in children with no contraindications for local anesthetics.

The criteria for considering an article for publication in journals have undergone dramatic changes. Therefore, young researchers should get familiar with common errors and problems during designing studies and preparation of the articles reporting the results of studies. The present study was designed to investigate the most common mistakes that young researchers make during different phases of research protocols in order to improve the quality of research studies. The present review article was prepared by a comprehensive search in the ISI web of science to find articles that offer research guidelines for young researchers, with an emphasis on a recently published review article. Given possible errors during preparation of research articles, young researchers should have a sound knowledge of all the different stages of the study, which necessitates the evaluation of previous studies and familiarity with principles of research. Before any attempts to start a clinical study, the protocol and the design of the study should be precisely defined and the type of the study determined. In addition, the researcher should evaluate the statistical methods of the study himself/herself or with the help of a statistical consultant in relation to the adequacy of population size and efficacy of sampling procedures in order to increase the power and validity of the study. There are important considerations in clinical studies, attention to which can help young researchers.

After orthodontic treatment, certain cases have high potential of relaps.These cases reqire fixed retainers.Fixed lingual retainers were introducsd in 1970s and In the last 20years several different techniques for bonding fixed retainers have evolved.Review report: This review carried out by use of searching in various databases including Pubmed and Google Web of Science from 1973 to 2011 on combination of the terms orthodontic retainer and resin bonded retainer. The indirect method requires a laboratory procedure for holding the retainer´s wire on teeth surfaces for bonding but in the direct method,the retainer´s wire needs to be prefabricated for fit the lingual surface of the teeth.Several methods have been used to hold the wire on the teeth surfaces. In this article,we introduce some methods. Perception of advantages and disadvantages of several methods of placing lingual retainer, which are simple and cost-effective,enable the dentist to choose the most suitable method.

Mechanical tooth cleaning is arguably the most common plaque control procedure. However, due to complex bacterial etiology of periodontal diseases and caries and unreliability of mechanical plaque control procedures chemical agents to control microbial agents have attracted a lot of attention as useful adjunctive methods. The aim of the present study was to review the effect of mouthwashes and chewing gums on orodental health. In this review the protective role of mouthwashes and chewing gums in dental and oral health was evaluated by a comprehensive search in electronic databases such as ISI and Pubmed and a hand search of relevant journals and books from 1980 until 2011. Mouthwashes are known as the simplest system for the delivery of antiplaque and antimicrobial agents. Mouthwashes, similar to toothpastes, should have some characteristics, including the potential to remove enamel and dentin microbial plaques, cleaning properties, good taste, chemical stability and low cost. Common claims for the effects of chewing gums in regular users of xylitol-containing gums include removal of food debris and plaque from tooth surfaces, stimulation of salivary flow, increasing the pH of saliva and plaque, decreasing caries rate, and decreasing the incidence of gingivitis and periodontitis. The use of chewing gums to deliver fluoride and bicarbonate, and minerals such as calcium and phosphate into the oral cavity enhances acid-buffering capacity and decreases demineralization rate. Use of mouthwashes and sugar-free chewing gums, especially xylitol-containing chewing gums, alone or in combination with other dental-protective substances with optimal doses and time periods can be considered effective programs for high-risk populations to achieve oral health.

Behçet’s disease was initially described by Behçet as a triad of symptoms, including recurring oral ulcers, recurring genital ulcers, and ocular involvement. The aim of this study was to evaluate frequency of Behçet’s clinical manifestations in patients referring to Isfahan AL-Zahra Hospital during the ten-year period of 1998‒2008. In this descriptive survey, files of patients with Behçet’s syndrome were reviewed in Al-Zahra Hospital during 1998‒2008. Data regarding age, gender and prevalence of oral, genital, and cutaneous manifestations, and also arthritis, intestinal involvement, and thrombophlebitis were extracted. Data was analyzed by descriptive statistical tests using SPSS software. The frequencies of clinical manifestations were: oral manifestations, 78%; ocular lesions, 28%; genital lesions, 26%; arthritis, 19%; skin involvement, 16%; gastrointestinal involvement, 13%; thrombophlebitis, 1%. The manifestations were most common in the 31‒41 age group. Male-to-female ratio was 1.5:1. At present, Behçet’s syndrome is known as a multisystem disease with various manifestations. In this study oral manifestations were the most frequent symptoms in Behçet’s syndrome. Males were more commonly afflicted compared to females.