Journal of Dental Medicine

Background and Aims: The purpose of this study was to design a new device assisting dental students to measure the tapering of the prepared teeth for fixed crown prosthesis in which the desired tapering for better clinical prognosis could be obtained.

Materials and Methods: The designed device in this study had two arms that were placed on two opposite walls of the prepared teeth. To evaluate the validity and reliability of this device, 3 dies with different degrees (13, 29 and 45°) were used and 20 teeth were prepared by dental students with undefined tapering degrees. The measurements of tapering were performed by six last year-dental students in two different time periods. Comparison of errors in measurements on standard dies between observers and between time intervals were analyzed by (Wilcoxon) Paired t-test with a significance level of α=0.05.

Results: For the three dies used in this study, we compared the differences for each measurement taken by observers with the standard taper of the dies. Maximum difference of measurements with true standard die tapering was 1 degree. A number of 6 measurements were under the true standard tapers and 2 measurements were above it. Interclass Correlation Coefficients (ICC) of the first and second measurements on prepared teeth were 97.4 and 97.5, respectively.  There were no significant differences between different observers or two measurements of the same observer in different time intervals (P>0.05).

Conclusion: The results indicated that this device can be valid and reliable for measuring the angle of convergence of the prepared teeth and can be used as an educational device in dental schools as a replacement for previous tapering measurement methods.

Background and Aims: Calcium hydroxide has a pronounced antimicrobial activity against most of the bacterial species found in infected root canals and endodontic infections. It is one of the most frequently used intracanal medications in endodontic therapy. The objective of this study was to determine the antimicrobial efficacy of six calcium hydroxide formulations (mixed with saline, lidocaine 2%, chlorhexidine 2%, chlorhexidine 0.2%, Iodine Potassium iodide (IKI) 2%, and glycerin) on Enterococcus faecalis using agar diffusion test.
Materials and Methods: Twelve culture plates were incubated with Enterococcus faecalis. Five cavities were made in each plate with 5 mm diameter and 4 mm depth. Two plates were randomly considered for each calcium hydroxide formulation and filled completely with creamy mixture of tested materials. The plates were incubated at 37ºC for 48 hours. The diameter of inhibition zone around each well was recorded in millimetres and data were submitted to ANOVA and Tukey tests.
Results: The results of this study showed that all tested calcium hydroxide pastes had good antimicrobial activity. The antimicrobial activity of calcium hydroxide mixed with lidocaine, chlorhexidine 2% and IKI 2% were significantly greater than that of calcium hydroxide mixed with saline (P<0.001). No significant differences in the antimicrobial  were found between the other groups (P>0.01).
Conclusion: Considering the results of this study, lidocaine 2%, chlorhexidine 2% and IKI 2% are suggested to be used for preparation of calcium hydroxide paste. Further studies with different methods are needed for confirming these results.

Background and Aims: Discoloration of resin composites is considered to be the major factor in esthetic restoration failures. The aim of this study was to evaluate the color stability of resin composites after rebonding with two different adhesive materials.

Materials and Methods: Forty five composite disc samples were divided into three groups (n=15). The surface of specimens was finished by polishing disc and rubber. In group 1, any additional phase was not performed. In group 2, composite discs were etched by %37 orthophosphoric acid, then Margin- bond was used for rebonding. In group 3, the etching procedure was in the same manner used for group 2, but Permaseal was used after etching. After the first phase of spectrophotometric measurement, the specimens were dipped in coffee mix for 3 weeks for aging the specimens. Then the second phase of spectrophotometric evaluation was performed. Collected data was analyzed using one-way ANOVA test followed by Tukey test. P<0.05 was considered as the level of significance.

Results: The mean total color difference (∆E) observed in groups 1 to 3 were 1.4±0.34, 5.24±1.51, and 7.44±1.34, respectively. Statistical significant differences were shown between the groups (P<0.001).

Conclusion: Rebonding with adhesive materials used in this study did not increase the color stability of composite restorations.

Background and Aims: Successful pediatric dentistry depends not only on the dentist's technical skills, but also on his ability to acquire and maintain a child's cooperation. The correction of dentist’ action in this area affects the view of parents and increases the quality of dental services. The objective of this study was to evaluate the attitudes of general dentists toward methods of controlling pediatrics’ behavior in Isfahan.

Materials and Methods: This study is descriptive, analytic, and cross-sectional. For this research, 100 general dentists of Isfahan city were selected with simple random sampling technique and were asked to complete the questionnaire which was included four different management techniques. The data were analyzed with t-test, P earson’s correlation , ANOVA and Kruskal-Wallis.

Results: The methods accepted by dentists were Tell-Show-Do (4.0 ± 0.5), Voice control (3.5 ± 0.4), active restraint (3.0 ± 0.5) and Hand-Over-Mouth (2.9 ± 0.5) respectively. The mean score of female dentists’ attitudes was more toward the method of active restraint and less toward Hand-Over-Mouth technique. Also the average score of middle aged dentists’ attitudes toward Voice Control method was less than young dentists and toward Hand-Over-Mouth was higher. The general dentists with more number of pediatric patients had less consent on the method of Hand-Over-Mouth (P=0.004) and active restraint (P=0.034).

Conclusion: There were significant correlation between attitude of general dentists toward behavior management techniques with age, gender, clinical experience and the number of pediatric patients. General dentists have fewer tendencies to aggressive behavior management techniques.

Background and Aims: Periodontitis does not affect on all patients by the same way. There are some risk factors in some people that make them more sensitive to progress of periodontitis. Smoking, uncontrolled diabetes, and special pathogens increase the risk of periodontitis. Other factors such as stress, depression and anxiety, are not crucial risk factors for periodontitis yet. Biologic explanation of this relation is that mental conditions and exposure to stressful situations can alter immune response. The aim of this study was to review the psychological factors of anxiety and depression associated with periodontitis.

Materials and Methods: For this review article, we have searched through internet by the following keywords periodontal disease, anxiety, depression. We have tried to cover almost all dental– related sites and journals as well as Pubmed from 1990-2010.

Conclusion: Most published studies support a positive relationship between periodontitis and several psycho-social factors. Life style, stressful conditions, hormonal changes, nonchalance in oral hygiene, habits such as smoking are predisposing factors in periodontal diseases.

  Background and Aims: Oral health prepares us for daily activities without discomfort, and dissatisfaction. In this research, agreement level between parents and children aged 11-14 year-old in reporting child oral health-related quality of life was studied in Isfahan city.

  Materials and Methods: In this descriptive, analytical and cross-sectional study 128 pairs of parents and children aged 11-14 were selected with random sampling technique from 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 (α=0.05).

  Results: The agreements between PPQ_11-14 (parent perception questionnaire), CPQ_11-14 (child perception questionnaire) and the related fields were 0.81, -0.67. The highest agreement level (ICC=0.83) was related to emotional health (excellent), followed by functional deficits (ICC=0.80), social health (ICC=0.69) and oral signs (ICC=0.64). Pearson's test showed significant correlations between CPQ_11-14 and PPQ_11-14 (r=0.81) (P<0.01).

  Conclusion: 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.

  Background and Aims: Bleaching agents not only affect the tooth structure, but also may alter the properties of restorative materials. The aim of this in vitro study was to evaluate the effect of different bleaching regimens on the microhardness of four tooth-colored restorative materials.

  Materials and Methods: Eighty specimens of four restorative materials (Microhybrid resin composite (Z250 (3M, ESPE), nanohybrid composite Z350 (3M, ESPE), packable composite P60 (3M, ESPE), and resin modified glass ionomer Vitremer (3M, ESPE)) were fabricated and were polished after 24 h with Soflex discs (3M,ESPE). Then the specimens were divided into two groups: In office bleach group, 40 specimens (10 of each restorative material) were bleached with hydrogen peroxide 37.5% for 30 min in two sessions with 7 days interval. In home bleaching group, 40 specimens were bleached with carbamid peroxide 22%, 6 h a day for 14 days. Vickers microhardness test were done before and after bleaching (baseline). Finally data were evaluated using analysis of Variance.

  Results: Two bleaching regimens were significantly decreased the microhardness values. In Z250 resin composite, the microhardness values before and after bleaching were 95.30 and 92.67 kg/mm², respectively. for office bleaching (P=0.011) and 95.38 and 92.39 kg/mm² for home bleaching (P<0.001). In Z350 resin composite, the microhardness values before and after bleaching were 98.29 and 92.41 kg/mm², for office bleaching (P<0.001) and 97.35 and 93.44 kg/mm² for home bleaching (P<0.001) respectively. In P60 resin composite, the microhardness values before and after bleaching were 103.10 and 96.16 kg/mm², respectively. for office bleaching (P=0.045) and 102.61 and 98.16 kg/mm² for home bleaching (P=0.001). In resin modified glass ionomer (Vitremer), the microhardness values before and after bleaching were 56.79 and 49.41 kg/mm², respectively. for office bleaching (P=0.004) and 54.17 and 46.50 kg/mm² for home bleaching (P<0.001). There was no significant difference between two bleaching agents (P=0.365).

  Conclusion: Dental bleaching agents decrease the microhardness of tooth-colored restorative materials.

  U ntreated caries are common findings in low-income communities. Treatment of dental caries in young children is challenging and requires a high skill and high cost of dental anesthesia for control ling patients and thus, chemical methods for arresting dental caries have been proposed. Silver Diamine Fluoride (SDF) is a material that is used to control and to arrest dental caries , especially in primary teeth . It is noninvasive, safe , easy to use , and cost-effective. The SDF can be used as a therapeutic agent in oral health projects in low-income communities . In this article we review ed the silver diamine fluoride and its application in dentistry.

  Background and Aims: Since recurrent caries are one of the major causes of failure in resin restorations, the production of antibacterial resin composites was always under investigation. The aim of this study was to evaluate the efficacy of fissure sealants containing nanosilver particles against the Streptococcus mutans.

  Materials and Methods: In this experimental study, the antibacterial properties of two sealants (with fluoride (Clinpro 3M) and without fluoride (Concise 3M) was investigated with 0, 0.01, 0.02, 0.03, 0.04, 0.05% w/w after adding nano-silver using direct contact test. Sealants formed on the walls of 500ml micro tube and after curing, they left in contact with bacterial suspension. In periods of 3, 24, 48h, a 10 µl volume of liquid medium was placed in blood agar culture and after 24 h incubation at 37ºC, the number of S.mutans colony was counted by colony counter. Data were analyzed using ANOVA and
T-test.

  Results: Results reported sealants with fluoride comparing to non fluoride ones had significant effect on inhibition of S.mutans growth (P<0.001). The direct contact test demonstrated that by increasing the amount of nano particles, the bacterial growth was significantly diminished (P<0.001).

  Conclusion: While sealants with fluoride demonstrated antibacterial effect, sealants with incorporation of higher weight percentage of nanosilver particles, had stronger and more significant antibacterial effect in direct contact test.

  Background and Aims: Until now, different types of scaffolds are presented for hard tissue engineering and the research continues to find the best scaffold. The aim of this study was to prepare scaffolds using two types of composite materials, ChitosanTriCalcium Phosphate (C/TCP) and ChitosanTriCalcium Phosphate/ Hydroxy apatite (C/TCP/ HA) and to add either 10% or 20% gelatin to compare their influence on swelling ratio of the scaffolds and on their affinities towards Dental Pulp Stem Cells (DPSCs).

  Materials and Methods: Composite scaffolds containing 10 or 20 percent of gelatin were prepared by freeze drying method. To determine the percentage of water absorption, swelling ratio studies were performed. Cell attachment and cell viability of the composite scaffolds were studied using Scanning Electron Microscopy (SEM) and MTT ( dimethyl-thiazol-diphenyltetrazolium bromide ) assay. Data were analyzed using ANOVA and Turkey’s post hoc test. A P-value of <0.05 was considered to be statistically significant.

  Results: The C/TCP scaffold and scaffolds containing 20% gelatin showed good swelling character. The macroporous composite scaffolds exhibited different pore structures. The biological response of DPS cells on C/TCP scaffold, C/TCP scaffold containing 20% gelatin, and C/TCP/HA scaffold was superior in terms of cell attachment, proliferation, and spreading compared to the other scaffolds (P<0.05).

  Conclusion: Considering the limitations of this in vitro studies, the results demonstrated that enhanced gelatin content in the C/TCP scaffolds do not improve initial cell adhesion and proliferation of the DPSCs on these scaffolds.

  Background and Aims: Successful pediatric dentistry depends on the dentist's technical skills, as well as his/her ability to acquire and maintain a child's cooperation. The correction of dentist’ performance in this area affects the view of parents and increases the quality of dental services. The aim of this study was to evaluate the attitudes of general dentists toward behavior guidance techniques in Isfahan.

  Materials and Methods: In this descriptive- analytic cross-sectional study, 100 general dentists of Isfahan city were selected with simple random sampling technique. They were asked to complete the questionnaire inquiring their attitude toward four different behavioral management techniques . An appropriate question about each of the methods was proposed by the authors, along with demographic characteristics including: gender, age, university, year of graduation, work experience, the mean number of pediatric patients referred in one month was provided in the form of a questionnaire. To evaluate the attitude of dentists to the questionnaire, the score from 1 to 5 was given to each item and the total score was considered. Higher score indicated more positive attitude of dentist. Data were analyzed using T-test, Pearsons correlation and one-way ANOVA (P<0.05).

  Results: The mean scores for dental behavioral management techniques were positive reinforcement (4.2±2.7), general anesthesia (3.5±4.4), N₂O sedation (3.4±4.4) and pharmacologic sedation (3.2±2.7), respectively. There were no significant differences between the mean score of dentist attitude and age, gender, clinical experience and the number of pediatric patient (P>0.05).

  Conclusion: General dentists’ attitudes towards different behavior management techniques were associated with age, gender, clinical experience and the number of pediatric patient. General dentists’ tend was more towards non-drug behavior control methods such as positive reinforcement.

  Background and Aims: AIDS-associated oral lesions are important, in terms of diagnostic-prognostic role and monitoring patients moreover some of them may reduce patient’s quality of life. The aim of this study was to determine the prevalence of oral lesions in HIV patients.

  Materials and Methods: This descriptive cross-sectional study was carried out among a total of 62 HIV⁺ patients who attended a counseling and treatment center in Rasht. Demographic information, drugs and laboratory status were extracted from patients’ files. Data were analyzed using univariate and multivariate logistic regressions with multiple linear regressions.

  Results: From 62 cases, 50 were male and 12 female and the mean age was 40.5±11.3 years. 59 patients had oral lesions including periodontal disease (95%). The most prevalent oral lesions included: periodontitis (67.7%), oral candidiasis (41.9%) of erythematous (35.4%) and pseudomembranous types (6.45%) and angular cheilitis (12.9%). Patients with removable denture presented a higher rate of erythematous candidiasis and angular cheilitis (P=0.001). In this study, periodontal diseases were rosed by the post-diagnosis years (P=0.024) and the antiretroviral medications (P=0.002). Patients on the prophylactic medications (P=0.043) were less likely to have erythematous candidiasis age may caused angular cheilitis (P=0.041). Pseudomembranous candidiasis was inversely correlated with CD₄ + L levels (P=0.052).

  Conclusion: The majority of the cases in this study were IV drug user males within the 4th decade of life. Although oral lesions were not common, but the dental and periodontal statuses exhibited poor oral hygiene which need more attention.

  Background and Aims: The most effective preventing tooth decay method is fluoride compounds applications. Some studies suggested that APF gels caused changes on the superficial physical properties of composite. Therefore, the purpose of this study was to evaluate the marginal microleakage of class V composite restorations before and after AFP gel application.

  Materials and Methods: The class V cavities in buccal surfaces of 45 molar teeth were made in such a way that occlusal margin was placed in enamel and cervical margin in cement. In group 1, at first fluoride-therapy and then cavity preparation and restoration by composite resin was done. In group 2, at first the class V cavities were prepared and restored, then fluoride-therapy was carried out. In group 3, cavities were prepared and restored with no fluoride-therapy. The dye penetration rate in occlusal and cervical margins was examined by stereomicroscope. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney test.

  Results: There was no statistically significant difference between groups ( P=0.975).

  Conclusion: Fluoride-therapy using AFP gel before and after class V composite restorations, had no significant effect on the microleakage of dentin and enamel margins.

  Background and Aims: To ensure root canal treatment success, endodontic microbiota should be efficiently reduced. Several irrigation devices have been recently introduced with the main objective of improving root canal disinfection.The purpose of this study was to evaluate the rinsing effect of RinsEndo system in reduction of enterococcus faecalis in comparison with conventional hand syringe in infected root canals.

  Materials and Methods: 60 extracted single canal anterior teeth were infected with enterococcus faecalis and divided into 3 groups: RinsEndo system, conventional hand syringe and control group. The enterococcus faecalis colonies were counted in each group before and after rinsing. Data were analyzed using Variance and Kruskal Wallis test.

  Results: The mean of enterococcus faecalis growth after rinsing was 3.50×10³ in group with conventional syring rinsing, 2.04×10³ in group with RinsEndo washing and 6.11×10³ in control group. Reduction of enterococcus faecalis after rinsing was statistically significant in each group (P<0.001). The amount of reduction in number of colonies with RinsEndo and conventional syringe rinsing was higher in comparison with control group and this difference was significant (P<0.001). RinsEndo rinsing effect was statistically significantly higher in comparison to conventional syringe as well (P<0.001).

  Conclusion: Rinsing with RinsEndo system was significantly more efficient in reduction of enterococcus faecalis from root canal in comparison with hand syringe washing.

  Background and Aims: Diagnosis of vertical root fractures often poses a clinical dilemma. Diagnosis of VRF in intraoral radiographs, except in cases where the beam is perpendicular to the direction of fracture is difficult. Misdiagnosis often leads to wrong decisions about the design of teeth future treatment plan. The aim of this study was to determine the diagnostic accuracy of reverse contrast enhancement options in digital radiography, and to compare it with the original images to find a suitable method to detect vertical root fracture.

  Materials and Methods: In this experimental study, digital radiography with phosphor plate detector was taken from 40 extracted single root teeth. From each intact and fractured tooth, the original and reverse contrast images captured and stored. Two expert observers viewed the images twice with an interval of two weeks. Diagnostic criteria (Accuracy, PPV, NPV, Specificity and Sensitivity) in form of absolute and complete for each observer and each images was calculated. Inter and intra observer reliability was obtained using Mc-Nemar test.

  Results: No significant differences in inter-observer reliability between the initial appearance and reverse contrast was observed (P>0.05), but in view of the intra-observer reliability in two cases, the difference was significant (P<0.05). No significant difference in the accuracy, sensitivity, specificity and PPV was observe between the two used images (P>0.05), whereas significant difference between the two images was found in NPV index (P<0.05).

  Conclusion: The use of reverse contrast enhancement option for detection of vertical root fracture did not show significant difference from initial view.

  Dental caries is a multi-factorial disease and the most common human infection that annually are spent millions dollars to control and treat it. Several methods have been proposed so far to control it. The most important control methods it is now include : dental hygiene, proper nutrition , fluoride therapy , the use of non- cariogenic sweeteners . Also, the use of probiotics , nanomaterials , bacteriophages , antimicrobial peptides and anti- caries vaccines can be considered as new perspective of human in the dental caries control field. In addition, the use of complementary and alternative therapies , especially herbal drug therapy recently has been considered . Demonstrating the efficacy of complementary medicine against dental caries and its use in combination with conventional medicine or trial of new methods for decline of dental caries in the future would be hopeful.