Caspian Journal of Dental Research

1-7

Authors: Nedasadat Tavoosi , Mehdi Rafiei * , Eilnaz Ehrami , Nasim Jafari Pozveh

Introduction: After the third molars, the maxillary canines are the most frequently impacted teeth. Sella turcica bridging (STB) can be used as a predictive factor to help orthodontists in early diagnosis. The aim of this study was to investigate the relationship between palatal canine impaction (PCI) and STB. Materials & Methods: In this case-control study, in available lateral cephalograms and panoramic radiographs of 53 patients with PCI and 53 controls with normal dentition and no impacted canines the dimensions of STB were measured and graded. Grade I (no calcification): The length of the sella is greater than ¾ of its diameter.Grade II (partial calcification): The length of the sella is equal to or less than ¾ of its diameter.Grade III (complete calcification): A separation bridge is clearly visible on the radiograph. The patients and controls were between 12 and 20 years of age. The relationship between STB and PCI was analyzed using the Chi-square test, Mann-Whitney test, and Fisher’s exact test. A value of P<0.05 was considered significant. Results: There was a significant relationship between STB and PCI (P<0.001). A significant relationship was also found between STB severity grade and PCI (P<0.001). The probability of the presence of Grade II STB in patients with PCI was three times higher than in those with normal dentition. The probability of the presence of Grade III STB in patients with PCI was approximately 46 times higher than in individuals with normal dentition. The length: diameter ratio of the sella turcica was not significantly different between the two groups of patients and controls. No significant relationship was found between gender and STB. Conclusion: The relationship between STB and PCI could be used as diagnostic early indicator to confirm PCI.

20-27

Authors: Mohadeseh Emampanahi , Mina Motallebnejad * , Niloofar Jenabian , Ali Akbar Moghadamnia , Sohrab Kazemi

Introduction: Nifedipine (NF) is a calcium channel blocker that accelerates wound healing and subsequently relieves pain and discomfort. The aim of the present study was to investigate the local effect of this drug on the wound-healing process of the palate. Materials & Methods: In this triple-blind clinical trial study, 31 patients who were referred to the Periodontology Department of Babol Dental School (14 in the experimental group and 17 in the control group) were examined. They were candidates for gingival surgery and needed a palate transplant. Mucotom was used to create identical wounds in the palate (transplant donor). After a free gingival grafting, the active ingredient of 0.3% NF was applied as a mucosal adhesive (made of chitosan) in the area of the graft (palate). Patients were examined and recorded on days 2, 4, 7, 14, and 30 after surgery for wound closure and healing criteria (Landry & Manchester scar scale) and pain (VAS). Sutures were removed on day 7 of the study. Data were analyzed with SPSS 20 and chi-square, Kruskal-Wallis and Mann-Whitney tests. The significance level was set at 0.05. Results: Based on Landry and Manchester criteria, the wound healing process in the two groups was not significant (p=0.125). There was no significant difference between mean wound size reduction and VAS in both treatment and control groups (p=0.253). Conclusion: Topical NF has no effect on the natural process of healing oral mucosal ulcers and reducing pain.

35-41

Authors: Mohammad Ghasemi , Atefeh Yoosefi , Mohammad Najdalizadeh , Mostafa Sheikhi **

Introduction: The composite resin bond strength to the enamel can be affected by contamination with various agents. Protective gloves are one of the factors which can cause contamination and disruption of the composite resin bond strength to the tooth structure. The aim of this study was to investigate the shear bond strength (SBS) of orthodontic brackets bonded with composite resin to enamel after contamination with powderless latex and nitrile gloves. Materials & Methods: A total of 208 orthodontic brackets were bonded on the mesial and distal of 104 intact extracted premolar teeth. The teeth were randomly divided into latex and nitrile groups. Each group was divided into test and control subgroups. In the test groups, the composite resin was placed with latex or nitrile gloves, and in the control group without contact with the gloves on the bracket base. The SBS of the samples was measured in a compressive test machine at a strain rate of 0.5 mm/min. The data were analyzed by independent t-test. The significance level was set at p<0.05. Results: There was no significant difference in SBS between the latex and nitrile subgroups with or without gloves. There was no significant difference between the latex and nitrile groups and their control groups. Conclusion: The use of powder-free latex gloves and nitrile gloves does not affect the SBS of composite resins; therefore, they are recommended for dental procedures.

69-76

Authors: Mostafa Ebrahimi , Reza Ghorbanipour , Tania Ghasemi , Ali Bijani , Maysam Mirzaie *

Introduction: Metal brackets are the most commonly used brackets in clinical orthodontics, but the sight of color of the metal bracket can be unpleasant for some patients. Ceramic brackets offer the desired beauty but they have higher frictional resistance. Considering that in vitro studies suggest that CO2 laser reduces the friction between the wire and slot of the bracket in the sliding mechanics, the aim of this study was to evaluate the clinical effect of CO2 laser on the speed of tooth movement using the sliding mechanics. Materials & Methods: This randomized double-blind clinical trial was performed on 7 patients and a total of 13 half jaws in each group. These patients were candidates for bilateral extraction of the first premolars due to lack of space or dentoalveolar protrusion. After alignment and leveling, the ceramic brackets were passively bonded. The ceramic brackets of the experimental group irradiated with the CO2 laser and the brackets of the control group were bonded unchanged. The brackets were examined with an atomic force microscope (AFM) before and after irradiation. Statistical data were analyzed paired t-test to compare the rate of gap closure between the two groups at one-month intervals. ANOVA was used to examine the reduction in spacing at three-month intervals. A value of p<0.05 was considered statistically significant. Results: The rate of gap closure between the two groups was compared at one-month intervals, which was not statistically significant in either month. Furthermore, in the comparison between the study and control groups, the decrease in the distance between the canine and second premolars was not statistically significant after a total of three months (p=0.0918). Conclusion: According to the results of this study, CO2 laser irradiation of the bracket surface has no effect on the speed of movement of the canine when sliding on the wire.

85-90

Authors: Arezoo Yadollahzade , Taghi Amiriani , Elham Fakhari *

Introduction: The oral cavity has been suggested as a potential reservoir for Helicobacter pylori (H. pylori), which could be a major cause of reinfection after standard systemic therapy. The aim of this study was to evaluate the effect of full-mouth disinfection (FMD) on the recurrence of H. pylori infection. Materials & Methods: This randomized clinical trial was conducted on 40 patients with chronic periodontitis and H. pylori infection. Of these, 20 patients received quadruple anti-H. pylori therapy only (group A) and the other 20 patients received quadruple therapy plus FMD (group B). The presence of H. pylori was detected by a 14C-urea breath test (UBT) after 1 and 6 months. Data were analyzed with SPSS 16 using the chi-square test. A value of p<0.05 was considered statistically significant. Results: Of 40 dyspeptic patients, 15(75%) and 18(90%) of 20 in groups A and B, respectively, had a negative UBT after 4 weeks. Of the patients with successful eradication of H. pylori after 1 month, 8(53.3%) and 6(33.3%) of 15 in group A and 18 in group B, respectively had a positive UBT after 6 months. There were no statistically significant differences between the two groups in the follow-up periods (p>0.05). Conclusion: Implementation of quadruple therapy plus FMD may reduce recurrence of the infection although further studies are recommended to confirm the results.

98-105

Authors: Zahra Shokri , Maryam Seyedmajidi , Mahdi Pouramir , Ali Bijani , Raheleh Ahmadian , Mina Motallebnejad *

Introduction: Oral lichen planus (OLP) is a chronic mucocutaneous inflammatory disorder with an unknown etiology. Although a considerable body of evidence suggests that immunologic factors are involved in the etiology of OLP, the involvement of cytokines in the pathogenesis of the disease is not fully understood yet. The aim of the present study was to assess interleukin-6 (IL-6) levels as a proinflammatory cytokine in the saliva of OLP patients compared to healthy controls. Materials & Methods: This case-control study was conducted on 30 OLP patients (12 males and 18 females) and 30 healthy control subjects, selected from individuals who were referred to the Department of Oral and Maxillofacial Diseases in Faculty of Dentistry, Babol University of Medical Sciences. Samples of unstimulated saliva were collected. Salivary IL-6 levels were measured using an ELISA kit and compared between OLP patients and healthy controls. The collected data were analyzed by Chi-square, independent t-test, and receiver operating characteristic (ROC) curve using SPSS 18 Sensitivity, specificity, positive predictive values (PPVs), and negative predictive values (NPVs) ​​were calculated. A value of p<0.05 was considered significant. Results: Mean salivary IL-6 values in OLP patients and healthy controls were 24.68±9.90 ng/L and 13.76±9.27 ng/L, respectively. The difference was statistically significant (P<0.001). The mean IL-6 values in reticular and erosive forms of OLP clinically were 24.35±9.26 ng/L and 24.91±10.64 ng/L, respectively. This difference was not statistically significant (P=0.87). Conclusions: Higher levels of IL-6 in saliva of OLP patients compared with healthy controls support the role of IL-6 in the pathogenesis of the disease.

115-123

Authors: Narges Mirzania , Elham Zajkani , Armaghan Naghili *

Introduction: Recently, a new category of dental bonding agents called universal adhesives has been introduced to the market, which are claimed to be able to create a strong bond between composite resins and teeth, metal surfaces and all types of ceramics alone and without the use of other primers. The aim of this study was to evaluate the performance of universal adhesives in the repair of amalgam restorations with composite resins in comparison with the conventional method. Material & Methods: In this experimental in vitro study, 80 amalgam blocks were prepared and after abrading the surface with an intraoral sandblaster and performing the aging process, the specimens were divided into 4 groups of 20 each, depending on how each surface was prepared by different bonding in the following order: Single Bond2 (S), Alloy Primer and Single Bond (AS), G-Premio Bond (G) and Alloy Primer and G-Premio Bond (AG). The composite blocks were then cured on the surface of the specimens. Finally, the specimens were tested for micro-shear bond strength (µSBS) using a micro-tensile tester and their cross-section was examined for fracture pattern under a stereomicroscope. Data were analyzed using Kruskal-Wallis, Man Whitney, and chi-square tests. A value of P<0.05 was considered significant. Results: The highest and lowest bond strengths belonged to the AG and S groups, respectively. The mean difference of µSBS in the four groups was significant, except in the AS and G groups. Conclusion: G-Premio universal bond is able to create sufficient bond strength between composite and amalgam. However, it is recommended to use a combination of Alloy Primer with all bonding systems to improve bond strength.

130-135

Authors: Pegah Mosannen Mozafari , Nooshin Mohtasham , Mehrzad Khorshid * , Mostafa Alizadeh Abkooh , Shohreh Taherimoghadam

Peripheral ameloblastoma (PA) is a rare subtype of ameloblastoma that occurs in soft tissue. It most commonly affects the mandible and is more common in males. It most commonly occurs in the sixth decade of life. This case report represented a 19-year-old girl with a 10-mm lesion on the lingual gingiva of the mandible. The surface was papillary and no pain or bleeding was noted. Histopathologic examination revealed neoplastic proliferation of odontogenic epithelial cells nested in a connective tissue context. Unlike many other PA cases, these nests appeared to originate from the basal cell layer of the epithelium. Cone-beam computed tomography and orthopantomogram did not reveal severe bone involvement and aggression. The patient is planned to be followed-up for 10 years. The prognosis of patients with PA is generally good, but cases of lesion recurrence have been reported. Due to the rarity of PA, further studies are needed on its development and treatment outcome.

8-14

Authors: Pouya Abedi , Zahra Mohyadin , Sara Hosseini , Mehdi Abbasi *

Introduction: Residual oxygen-free radicals of bleaching agents before composite restorations can increase microleakage in enamel and dentin margins, and also various bleaching techniques are being developed using light sources. The present study was conducted to compare the effect of diode laser bleaching and LED activated bleaching on the microleakage of composite restorations. Materials & Methods: This in-vitro study was conducted on 84 extracted human premolars in three groups: In group one, class-V cavities were prepared and the teeth (n=12) were restored with composite ten days after bleaching with 35% hydrogen peroxide with no activator. In groups two and three (n=36 each), the teeth were bleached with a Diode laser activator and LED, respectively. Thereafter, each group was divided into three subgroups (n=12), cavities were prepared and restored with composite three, five, and ten days after bleaching. Digital photographs were used to assess microleakage in the enamel and dentin margins. Data were analyzed using Friedman and Wilcoxon Signed Ranks tests (p<0.05). Results: The lowest amount of microleakage in the enamel margin pertained to the diode laser ten-day subgroup (0.17±0.38) and the diode laser ten-day subgroup in the dentin margin (0.50±1.03). Also, the highest amount of microleakage in the LED group was in the three-day subgroup of the dentin margin (2.78±0.42). Five-day subgroup of diode laser-activated bleaching had a lower amount of microleakage compared to the control group (P=0.042). Conclusion: It may be concluded that diode laser-activated bleaching with 35% hydrogen peroxide has a better effect on reducing microleakage with an interval of five to ten days, compared to the control and LED activated bleaching group.

21-29

Authors: Farzaneh Mohammadi , Fatemeh Koohpeima , Mohammad Javad Mokhtari *

Introduction: Metal nanoparticles may apply to the cavity walls as acceptable antibacterial agents. The present work was conducted to assess the effect of silver nanoparticles (NPs) on the resin cements Shear Bond Strength (SBS) using one self-etch and one etch and rinse resin cement. Materials & Methods: Sixty intact noncarious extracted, human third molars were selected. All teeth were cut out in the middle of dentin thickness. Resin cement samples were randomly assigned to five groups: (A) Duolink cement without any further surface treatment; (B) Duolink cement with silver NPs (0.5%) dentin surface treatment after acid etching and before the One Step Plus (OSP) adhesive system; (C) Duolink cement with silver NPs (0.5%) dentin surface treatment before acid etching and OSP; (D) Panavia F2.0 cement without any further surface treatment; and (E) Panavia F2.0 cement with silver NPs (0.5%) dentin surface treatment. SBS was assessed by using universal testing machine. Then, human gingival fibroblasts (HGF) cells were treated with tested materials. The biocompatibility of resin cement was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay. Results: The maximum and minimum of the SBS at the presence of silver NPs were observed in group E (15.81±0.91, P-value<0.01) and group B (12.01±0.15, P-value <0.05), respectively. In comparison with the controls, the resin cements incorporated with 0, 0.2% and 0.5% silver NPs, 20.34%, 22.00% and 22.67% for Panavia F2.0 and 36.84%, 37.34% and 38.17% for Duolink flow - decreased in total cell number, respectively (P-value<0.01). Conclusion: These findings demonstrated that Panavia F2.0 cement with silver NPs dentin surface treatment showed satisfactory result in the SBS compared to Panavia F2.0 cement without any further surface treatment.

38-45

Authors: Yasin Baghban , Imaneh Asgari *

Introduction: Demanding qualitative dental services calls for hiring competent staff in dental offices. This study was designed to evaluate dental assistants' educational status and ability to perform tasks. Materials & Methods: In this cross-sectional study, 200 dental assistants working in the offices and clinics of Isfahan, Iran during 2020 were selected using random systematic sampling. The researcher-made evaluation tool with a content validity index of 0.77 was used. Tasks were evaluated by 13 items in 6 sub-scales including communication skills, preparation, radiography, cooperation with dentists, health promotion through prevention and infection control. Moreover, information was requested about the education and training course of the dental assistant. The score of ability was achieved at the range of 0 to 20. The relationship between gender and training course as well as between age and experience level was evaluated with Mann-Whitney test and Spearman correlation. Results: The most frequent major of the study was accounting. The mean total ability score of the dental assistants was 19.1±6.5, ranging from 17.7 to 20. The highest and lowest ability scores were related to the cooperation with dentists and health promotion through prevention, respectively. The mean ability score had a weak relationship with age but had no significant relationship with experience. The mean ability score only in the area of radiography had a significant relationship with the training course and gender (P=0.012). Conclusion: Despite the diversity in the degree and field of study, the ability and task status of the assistants was desirable. In the area of health promotion through prevention, there is a need for training and monitoring its implementation.

56-63

Authors: Azadeh Zakariaee Jubari , Azadeh Torkzadeh *

Introduction: The maxillary sinuses are the largest paranasal sinuses adjacent to the teeth. Due to anatomical variations in different people, knowledge of these variations is essential for rhinoplasty and sinusitis. The aim of the present study was to determine the relationship between maxillary sinus volume with nasal septal deviation, concha bullosa and infundibulum size using cone-beam computed tomography (CBCT). Materials & Methods: In this descriptive -analytical study, CBCT images of 135 patients who underwent maxillofacial imaging were evaluated. In order to measure the volume of maxillary sinuses, CBCT images of axial sections were used with a thickness of 2 mm and Digimizer image analysis software. In the coronary section of nasal septum deviation, types of concha bullosa and infundibulum size were determined. Data were analyzed using one-way ANOVA, paired t-test, Pearson correlation test and regression. A value of P<0.05 was considered significant. Results: There was a significant inverse relationship between the mean of volume of the right sinus (p=0.012, r=-0.216) and left sinus (p<0.001, r=-0.303) with the deviation of the nasal septum. A significant inverse relationship was found between the mean volume of right maxillary sinus (p<0.012, r=-0.357) and left maxillary sinus (p=0.006, r=-0.357) with infundibulum size. The mean volume of right and left sinues from coronal view was not significantly different in the presence or absence of concha bullosa. There was no significant difference between male and female in the mean volume of the right and left sinuses. Conclusion: The present findings suggest that maxillary sinus volume is smaller the deviation in moderate and severe septal deviation cases and that the maxillary and with increasing size of infandibulum, the volume of maxillary sinus was larger.

8-19

Authors: Mahsa Malekmohammadi , Azita Tehranchi , Maryam Sadeghipour , Nona Attaran , Mohsen Dalband , Mahshid Namdari , Zohre Ahangari , Mehdi Ekhlasmand Kermani *

Introduction: Mental health is an inseparable part of overall health and healthcare workers have experienced mental issues during the COVID-19 pandemic. This study aimed to investigate the amount of stress undergone by dental students and its affecting factors. Materials & Methods: This cross-sectional study included all students of Shahid Beheshti Dental School, Tehran. The data on demographic and individual-social characteristics of the participants and questions related to the perceived stress level (PSS-10 questionnaire) were collected using an online questionnaire. The results were analyzed using a T-test and the correlations in SPSS-26 (P<0.05). Results: A total of 511 students participated in the study. The mean score of the perceived stress level was 15.9 out of 40, indicating a moderate level of perceived stress. Eleven students had suffered from COVID-19 and 13% were in close contact with those infected. Most of the students (72%) used public transportation. About 60% regularly did exercise, and the majority had enough hours of sleep. After examining the relationship between the individual factors and perceived stress level, it was revealed that the PSS was significantly lower in people who had adequate and a regular sleeping timetable (p<0.05). Furthermore, people who had contracted the COVID-19 virus (p=0.019) or had relatives who were infected (p =0.007) experienced higher levels of stress. Suffering from preexisting medical conditions was another significant factor in higher perceived stress levels (p=0.027). Conclusion: This study indicated that students had gone through a moderate level of stress during the COVID-19 pandemic. People with systemic conditions, sleep disorders, and those who had contracted the COVID-19 virus themselves or their reletives, experienced higher levels of stress. The requirement to provide courses on stress management skills, family awareness, and use of mental health services to reduce the negative effects of this psychological burden is highly recommended.

30-37

Authors: Zahra Tafakhori * , Mehrad Rafiei

Introduction: Considering the effect of ethnicity and race on the root canal morphology of different teeth, this study was conducted to determine the root canal anatomy of permanent maxillary first premolars using cone-beam computed tomography (CBCT) in an Iranian population. Materials & Methods: This descriptive cross-sectional study was performed on 150 CBCT radiographs of an Iranian population, referred to a Radiology Clinic in Rafsanjan, Iran. The CBCT images were evaluated in terms of the number of roots and canals of maxillary first premolar and also canal types in axial and sagittal images. The Vertucci classification was used for assessing the root morphology. Data were collected using a checklist. The independent t-test and Chi-square test were used and analyzed at a significance level of 0.05. Results: A study of 150 radiographs showed that 81 and 69 ones had one root and two roots, respectively. In terms of canal type in the single-root teeth, 13 radiographs (16%) were type I, 36 (44.4%) were type II, 6 (7.4%) were type III, 17 (21%) were type IV, two (2.5%) were type V, four (4.9%) were type VI, and three (16%) were type VII. It should be noted that none of the radiographs had a type-VIII canal. Conclusion: This study has indicated that the Iranian population has a complex maxillary first premolars root canal morphology, and according to Vertucci classification, types II and IV are more common; hence, the Clinician must be very careful before treating the root canal of the first maxillary premolars.

45-51

Authors: Faezeh Heydari , Hemmat Gholinia , Reza Ghorbanipour *

Introduction: Palatal rugae is a collection of mucosal folds in front of the palatal and is unique to each individual. Rugae have been studied for various purposes. This research investigates the pattern of palatal rugae with different skeletal relationships in the sagittal dimension in a group of the Iranian population. Materials & Methods: A cross-sectional study was examined on 135 pre-orthodontic dental casts. The patients were grouped as Class I, Class II, and Class III according to the Nasion -A to Nasion -B angle (ANB) 45 patients in each group. Palatal rugae were recorded based on length, orientation, and pattern in each group, then compared. Data were analyzed by Chi-square, ANOVA, and Tukey post hoc test. In this study p<0.05 was considered significant. Results: The mean number of total rugae was significantly different among groups (p value=0.02). Cl III malocclusion had less number of rugae in comparison to other groups (p value=0.03). The number of straight pattern was significantly different between groups, (p value=0.04) and Cl I malocclusion had more straight pattern than other groups . Conclusion:This study showed some differences in the palatal rugae pattern between different classes of malocclusion according to Angle’s classificatin. In addition, orientation of some rugae were also found to be significantly different between malocclusiongroups.

60-64

Authors: Ehsan Rouhollahpour , Maryam Rezaei Dastjerdi , Mohammad Ebrahim Ahmadnezhad , Kamran Amirian Chaijan *

Introduction: Today, the use of all-ceramic restorations has increased due to their physical properties as well as translucency and esthetic appearance.The aim of this study was to compare the shear bond strength (SBS) between two methods of e-max ceramic cementing. Materials & Methods: The study groups were 1 flowable composite as cement (FC group) and 2) choice2 cement (C2 group). The samples were fixed to a KOOPA universal testing machine for SBS testing. Tthe data were analyzed using SPSS 20 through T-test at significant level of P˂0.05. Results: The average SBS in the FC group was 10.41±2.17 and The average SBS in the C2 group was 13.28 ±1.52. There was a statistically significant difference between the SBS of both groups (p<0.001). Conclusion: This study demonstrated that ,the use of flowable composite instead of C2 cement is not recommended for cementing e-max ceramics.

8-18

Authors: Lily A. Hartsock, Alexandre R. Vieira*

Introduction: The goal of this study was to test the impact of both diabetes type and control via the hemoglobin A1C biomarker on oral health outcomes. Materials & Methods: In this observational study, data were extracted from the University of Pittsburgh Dental Registry and DNA Repository and analyzed. From 6,026 subjects, 414 ones with a diagnosis of diabetes were matched by sex, age and ethnicity with 414 individuals without diabetes. A number of statistical approaches (chi-square, Fisher’s exact, Student’s t, Wilcox, and Mann Whitney tests) were used and all comparisons were set with an alpha of 0.05. Results: Patients with type 1 diabetes experienced xerostomia more often compared to non-diabetic matched pairs (p=0.02). Patients with diabetes (n=414) experienced temporomandibular joint (TMJ) discomfort more often than their non-diabetic matched pairs, as did type 1 diabetic patients alone, in comparison to both their matched pairs and type 2 diabetic patients (p=0.01, p=0.004, and p=0.02, respectively). Among patients grouped by diabetic control, all patients reporting control (n=39) experienced xerostomia more often than their non-diabetic matched pairs (p=0.05). Patients in poor diabetic control experienced restoration failure more often than patients in good control (p=0.04). The experience of restoration failure was no different between patients in good diabetic control and their matched controls (p=0.26). The number of restoration failures was higher in patients in poor control, as compared to their matched non-diabetic controls (p=0.03). Conclusion: Patients with diabetes experienced xerostomia but not necessarily more severe caries experience, and may be protected from TMJ discomfort. Patients in good control of their diabetes were at no greater risk for restoration failure as compared to non-diabetic patients; however, the patients in poor control were at higher risk for failed restorations.

27-34

Authors: Zahra Lari, Fariba Ezoji, Hemmat Gholinia, Effat Khodadadi*

Introduction: The resin-modified glass ionomer (RMGI) materials are hybrid materials including conventional glass ionomer and small addition resin. They have the advantages of both, such as adhesion to tooth structure, esthetics and fluoride release. The purpose of this study was to compare the fluoride release and wear resistance of two types of RMGI. Materials & Methods: In this in vitro study, specimens for measuring the fluoride release were made with brass mold from two types of RMGI EQUIA Forte glass ionomer and Fuji II conventional glass ionomer. After incubating the specimens in a plastic vial containing 7 ml of distilled water, the release of fluoride for each specimen was measured on days 1, 7 and 15 using a PH/Ion meter device. For evaluating the wear resistance, 8 specimens were prepared using a brass mold in each group. Then, each specimen was exposed to 5000, 10000, 20000, 40000, 80000 and 120000 cycles in wear simulator. The specimens’ weight was measured by an electronic weight balance before and after each wear cycle. The data were analyzed by SPSS-17 through repeated-measurement ANOVA and independent T-test. Results: Fluoride released from Fuji II glass ionomer was significantly higher in the first 24 hours and on day 7. During the day 15, the differences in fluoride release between the two glass ionomer groups were not statistically significant. (p<0.001). The EQUIA Forte glass ionomer exhibited significantly greater wear resistance in different wear cycles. (p<0.001) Conclusion: Due to its good wear resistance, acceptable fluoride release, ease of clinical use and infection control, the capsular glass ionomer can be a useful material in people at high risk of caries, temporary restoration techniques, pediatric dentistry and root caries.

42-47

Authors: Motahareh Zarei, Mehdi Rajabnia, Ali Akbar Moghadamnia, Soraya Khafri, Effat Khodadadi*

Introduction: Due to the limitations of chemical antimicrobial methods in the treatment of dental caries, the recent studies have focused on the use of plant-derived antibacterial agents to inhibit tooth decay bacteria. Therefore, the aim of this study was to investigate the effect of Vitis vinifera seed extract (VVSE) on Lactobacillus acidophilus and casei bacteria. Material & Methods: In this cross-sectional study, the VVSs were dried, the obtained powder was poured into separate containers to prepare aqueous, alcoholic and acetone extracts, and the desired solvents were added. After being placed in the shaker incubator and passing through the filter paper, the solvents were transferred to the plates. After cultivation of Lactobacillus acidophilus and casei bacteria in tubes containing Mueller Hinton Broth, the aqueous, alcoholic and acetone extracts were added to them. A tube with no extract was considered as control. The resulting samples were cultured on chocolate agar medium. The initial concentrations (2, 4 and 8 μg/ml) were not able to inhibit bacterial growth; thus, the higher concentrations were assessed to determine minimum inhibitory concentration (MIC). The data were analyzed using SPSS-17 via Chi-square, Mann-Witney and Kruskal-Wallis. Moreover, α=0.05 was considered significant. Results: The MIC of aqueous extract was 32 and 64 μg/ml for Lactobacillus acidophilus and casei, respectively. The alcoholic extract stopped the growth of both bacteria at concentration of 128 μg/ml. The MIC of acetone extract was 64 and 128 μg/ml for Lactobacillus acidophilus and casei, respectively. So, aqueous extract was more effective than alcoholic one (p=0.016). However, there was no significant difference between alcoholic and acetone (p=0.1267) as well as aqueous and acetone (p=0.061) extracts. Conclusion: Antibacterial activity of aqueous extract was more than that of alcoholic and acetone extracts. Alcoholic and acetone extracts had no significant difference in inhibition of bacterial growth. Therefore, it is possible to use aqueous extract of VVSs to control caries.

57-63

Authors: Masoumeh Mohsen pourian, Azin Alasvand Javadi, Mohammad Yazdizadeh*

Introduction: Effective endodontic treatment requires identification of all root canals. The inability of dentists to locate all root canals can lead to failure in endodontic treatment. Consequently, an accurate diagnostic device is essential to detect all root canals. The aim of this study was to examine the accuracy of cone-beam computed tomography (CBCT) as a diagnostic tool to detect the root canals of maxillary first premolars in a selected Iranian population. Material & Methods: In this in vitro study, 48 human extracted maxillary first premolar teeth were scanned by CBCT, and then all teeth were sectioned. In the current study, sectional method was chosen as the gold standard. The CBCT scans were observed by an oral and maxillofacial radiologist, and the sections were evaluated by an endodontist using stereomicroscope. Finally, the collected data were entered into SPSS- 22 and analyzed by Kappa coefficient and Chi-square test. Significance level was set at 0.05. Results: The agreement between CBCT and sectional methods for root canal detection was 97.2% which was significant (95.8% in the first section, 97.9% in the second and third sections), (p <0.001). Conclusion: It seems that CBCT is a safe and non-invasive tool that can be used to detect root canals if other low-dose radiation imaging techniques do not provide acceptable results.