Showing 21 results for Mehdi
Alireza Heidari, Mehdi Shahrabi, Sara Ghadimi, Shahram Mosharafian, Hosein Ansari, Zohreh Rafiee,
Volume 25, Issue 2 (9 2012)
Abstract
Background and Aims: Using the conservative adhesive resin restoration (CAR) in uncooperative children lead to numerous problems because of being time consuming. The purpose of this study was to compare the microleakage of conservative adhesive resin restoration under separate curing and co-curing.
Materials and Methods: In this experimental study, 120 intact premolar teeth were collected and 120 vertical grooves were prepared on them. Then the teeth were divided into four groups: group 1, separated curing of bonding agent, flowable composite and sealant group 2, co-curing of all materials for 60 seconds group 3,
co-curing of all materials for 40 seconds and group 4, co-curing of all materials for 20 seconds. Then the specimens were thermocycled and immersed in basic fuchsin solution. The teeth were sectioned horizontally and dye penetration was evaluated with stereomicroscope. Date were analyzed using one-way ANOVA and Scheffe test.
Results: Mean value of dye penetration in groups 1, 2, 3, and 4 was 1.53±0.6, 2.06±0.6, 2.5±0.7 and 3.53±0.6, respectively. There was a statistically significant difference between group 1 and the other groups (P=0.0001).
Conclusion: Considering the problems caused by microleakage in conservative resin adhesive restorations, co-curing method should not be used. In the case of using co-curing method, 60 second curing time is suggested for sufficient polymerization.
Mehdi Jafarzadeh Samani, Maryam Hajiahmadi, Samira Yousefi, Elham Sadat Binande,
Volume 26, Issue 2 (5-2013)
Abstract
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.
Mehdi Jafarzadeh, Maryam Haji Ahmadi, Hajar Esmaielian, Hadi Moshkel Gosha,
Volume 27, Issue 3 (9-2014)
Abstract
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.
Feizi Ghader , Kaviani Naser , Mehrparvar Roza , Binandeh Elham Sadaat , Tabrizizadeh Mehdi , Saatchi Masoud ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: Postoperativee endodontic pain is an outstanding problem for dental patients. Therefore, a successful management of endodontic pain has become as one of the main dental objectives. The aim of the present study was to compare the postoperative endodontic pain in patients under general anesthesia versus local anesthesia.
Materials and Methods: For conducting this clinical trial study, 50 patients having mandibular molars candidate for root canal therapy were selected. Twenty-five patients treated under general anesthesia because of their fear, anxiety or gag reflex. Other 25 patients treated under local anesthesia. All teeth were prepared using engine-driven rotary system in a crown-down technique and filled using lateral condensation technique. Heft- parker visual analog scale was used to measure the degree of pain at 6, 12, 24, and 48 hours after the treatment. Mann-Whitney, Chi-square, and T-tests were used to compare the intensity of postoperative pain between the groups.
Results: The mean intensity of postoperative pain in local and general anesthesia groups at 6, 12 and 24 hours had statistically significant difference (P<0.05).
Conclusion: Postoperative pain in patients who treated under general anesthesia was significantly less than the patients who treated under local anesthesia.
Haghgoo Roza , Rezvani Mohammad Bagher , Haghgoo Hamid Reaza , Ameli Nazila , Zeinabadi Mehdi Salehi ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: Dental caries is one of the most common infectious diseases which could be prevented in various ways. The aim of the present study was to evaluate the effect of a toothpaste containing different concentrations of nano-hydroxyapatite on the remineralization of incipient caries.
Materials and Methods: 9 sound first premolar teeth of maxilla and mandible were sectioned to four pieces. 6 specimens were stored in distilled water as control group. The remaining 30 specimens were demineralized for 72 hours and then their microhardness was measured. 0, 0.5, 1, 2 and 5% wt nano-hydroxyapatite were added to the solution of distilled water and toothpaste. Specimens were divided into 5 groups (N=6) and after demineralization, each group were randomly immersed in the above-mentioned solutions for 15 minutes. Next, specimens were kept in artificial saliva for 1 hour followed by immersion in the related remineralizing solution for another 15 minutes. This procedure was repeated for 5 days. Finally, the microhardness of the teeth was measured. Data were analyzed using repeated measures analysis of variance (ANOVA).
Results: The microhardness of demineralized teeth was increased following exposure to different concentrations of nano-hydroxyapatite, but this increase was not statistically significant (P=0.62).
Conclusion: Nano-hydroxy apatite can enhance remineralization and increase the tooth microhardness although this increase was not significant.
Motlagh Mehdi Ghandehari , Pourhashemi Seyyed Jalal , Ghadimi Sara , Baghae Farideh ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: Dental environment is a stressful place for children. In many cases, parents transmit their anxiety to their children in the first dental visit. Mothers as the closest person to the children may have important influence on their children’s behavior in dentistry. The purpose of this study was to evaluate the effectiveness of an educational pamphlet for mothers on children’s behavior in the first dental visit.
Materials and Methods: This study was conducted on 238 mothers who had 3-7 years old children undergoing dental treatment for the first time. The participants were divided into interventional and control group randomly. Behavior of children was assessed by questionnaire according to 4 point scale of Frankle. The questionnaire contained 5 parts: separation of child from the mother, entering the dental room, opening the mouth, communicating with dentist, getting the prize. Data were analyzed using Chi-square test.
Results: The educational pamphlet was effective on the separation of child from the mother, the cooperation of children in interventional group was better than the control group (P=0.006). In interventional group 96.2% of and in the control group 90.8% of children had good and very good behavior but the difference was not significant (P=0.11).
Conclusion: Although the educational pamphlet was effective on the separation of child from mother. No significant difference in behavior of 3-7 year-old children between interventional and control group was found.
Mehdi Araghbidikashani, Elham Esmaili, Gholamreza Eslami, Mohsen Nuori, Hasan Ghaffari, Abbas Salehi,
Volume 28, Issue 2 (7-2015)
Abstract
Background and Aims: The aim of this descriptive longitudinal study was to determine the type of teeth that were more prone in accidental bracket debonding and also to investigate the relationship between broken bracket bond and intervening factors such as age, type of malocclusion and sex.
Materials and Methods: We used a pilot study to determine the correct sample size for this study. According to the pilot study which consisted of 20 records of patients, it was concluded that 576 patient’ records was needed. The mean time for a bracket before it fails was also measured using Kaplan-Meier method. Cox regression analysis was done to examine the effect of age, gender, and class of malocclusion on each tooth with broken bracket. Data were analyzed using the software SPSS 20.
Results: Results showed that the percentage of unexpected broken bracket bond for each tooth varied and they were significantly related only in second premolars in both jaws with malocclusion that was different for each tooth (P=0.037, P=0.004).
Conclusion: Maxillary second premolars and mandibular second premolars had the highest rate of unexpected broken bracket bond in CL II CL I malocclusion respectively. Age, gender and malocclusion had no effect on the unexpected broken bracket bond for other teeth.
Fatemeh Mokhtari, Amir Hossein Mansor Abadi, Ali Gharaati Jahromi, Ehsan Anvar, Zandi Hengame, Tabrizi Zade Mehdi, Taghavi Mayam,
Volume 28, Issue 3 (10-2015)
Abstract
Background and Aims: Bacteria and their products have a major role in pulp and periapical diseases. The purpose of this study was to compare the antimicrobial activity of sodium hypochlorite, iodide potassium iodide and chlorhexidine on the enterococcus faecalis after root canal filling.
Materials and Methods: In this experimental study, 95 single canal human teeth were collected. Then after washing and cleaning and filing, the sterilization done using an autoclave. The teeth were smeared with enterococcus faecalis except five which selected as controls and then divided them into 3 groups which A randomly represented the irrigation by sodium hypochlorite, iodide potassium iodide (IKI) and chlorhexidine solution were done. The teeth were filled with gutta-percha and then incubated in a incubator for 90 days at a temperature of 37° C. The specimens were analyzed for Colony Count. Data were analyzed using Kruskal-Wallis test and Chi-Square.
Results: According to the results of this study, the correlation between the 3 groups of cultured teeth were not significant (P=0.812).The specimens which were washed by IKI had the most positive amount of cultures (23.3%) and the specimens which washed by chlorhexidine had the lowest (16.7%).
Conclusion: The results of this study showed that after the use of different wash solutions, no statistically significant difference exist in their antimicrobial activity after root canal therapy.
Shirazian Shiva , Arash Mansourian, Mehdi Vatanpour, Fatemeh Tirgar,
Volume 28, Issue 3 (10-2015)
Abstract
Background and Aims: The purpose of the present study was to investigate the relationship between study skills and academic performance of dental students in Tehran University of Medical Sciences.
Materials and Methods: 195 dental students at dental faculty of Tehran University of Medical Sciences in 2013 participated in this descriptive-analytical study. Data were collected using Congos´ Study Skills Inventory including six subscales. Grade Point Average (GPA) indicated their academic performance. Data were analyzed using ANOVA and Tukey test.
Results: The mean score of students’ study skills were 108 out of 200 with standard deviation of 22.06±0.7. Note taking had a significant correlation with GPA (P=0.015).
Conclusion: Since no significant correlation between study skills and academic performance of the students was observed, it seems that there are other dynamics involved in their academic performance which have to be examined.
Samaneh Bayat, Shirin Sakhdari, Ali Mokhtar, Ali Lotfi, Mehdi Amiri Siavashani,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: Central odontogenic fibroma is a rare odontogenic neoplasm that originates from odontogenic ectomesenchyme. Most cases occur in the mandible and between the ages of 11 and 39 years. The neoplasm shows a definite female preponderance, with a ratio of 2.2:1 and has a very low recurrence rate. The aim of this article was to report a case of this rare lesion which was accidentaly found.
Case Report: A 11-year-old female, during her orthodontic treatment and without any complain and any sign or symptoms, performed a panoramic image for assessing the permanent teeth buds. In the panoramic view a unilocular radiolucent lesion with well-defined and corticated borders in the right mandibular body region was evident. The lesion was treated with simple excision. Simple type of central odontogenic fibroma histopathologic features was observed in the microscopic view.
Conclusion: Although the central odontogenic fibroma is a rare benign neoplasm, however, a careful evaluation of radiographic images is important for early detection of lesions because the patient may have no clinical symptoms such as swelling, pain and paresthesia.
Arash Mansourian, Shiva Shirazian, Mohammad Jalili, Mehdi Vatanpour, Leila Pour Momen Arabi,
Volume 29, Issue 3 (10-2016)
Abstract
Background and Aims: The objective of this study was the development of a checklist for assessment of students’ clinical skills in the clinical oral medicine. The second aim was the assessment of stake holders’ satisfaction of this checklist in comparison to the routine global rating method.
Materials and Methods: The checklist was developed in an expert panel sessions and the validity and reliability of checklist were assessed by CVI and test-retest method, respectively. All students (n=66) were assessed in 2 groups, one with developed checklist and another with global rating. At the end of the session, the satisfaction’s level of staff and students were analysized using Wilcoxon and Mann-Whitney test and the mean scores of students were analysized using Paired T test.
Results: Content validity index (CV I) of checklist was 0.88. Reliability of checklist confirmed with high correlation coefficient (0.9). Staffs’ satisfaction had no significant difference between the two methods
(Wilcoxon P=0.06). The mean score of students who assessed by checklist was higher than global rating with no significant differences (P=0.06).
Conclusion: Regarding the higher students’ satisfaction from checklist and more attention to component of assessment and more objectivity of this method and also higher score in checklist, it seems that the use of a checklist is more proper method for assessing the students’ clinical skills.
Mehdi Abbasi, Aghil Rahmani, Ladan Ranjbar Omrani, Zohreh Moradi, Masumeh Hasani Tabatabaei, Sara Valizadeh,
Volume 31, Issue 3 (11-2018)
Abstract
Background and Aims: Color is the most important and complicated part of aesthetic dentistry. The tooth color matching of restorations is considered as one of the most difficult tasks in the restorative dentistry. The aim of this study to evaluate the effect of two training methods on the dental students’ ability in determining tooth color matching.
Materials and Methods: In this study, 40 dentistry students participated which randomly allocated into two groups. The first group consisted of students who learned teeth color matching methods practically. In the second group, training booklet was used for learning. Using Vita Classic shade guide series, 4 color samples were chosen and the students of each group were asked to determine samples’ color, before, after and one month after the training.
Results: Booklet learning group was more successful in determining fourth color sample. However, in no studied group and no used samples, the results of one month after learning were not better than that of before learning. Also generally, no significant relationship was found between the color matching accuracy, using glasses, and sex of participants.
Conclusion: The use of booklet learning was more effective than practical learning in color matching accuracy for dental students. Also, using glasses and sex were not effective on their color matching accuracy.
Ali Mohammad-Hoseini, Maryam Pirmoradian Najafabadi, Gholamreza Eslami Amirabadi, Mehdi Aragh Bidi Kashani,
Volume 33, Issue 1 (7-2020)
Abstract
Background and Aims: Elastomeric chains are known as a current device with the purpose of dental movement in orthodontic treatments. The aim of this study was to compare the elastomeric behavior and force degradation rate between different elastomeric chains existing in Iran in different time durations.
Materials and Methods: 11 different elastomeric chains used in this study were: Class One, ASTAR, G&H, TSNPT, MIB (French and Chinese type), Ultra Chain and both American, Ortho Technology (simple and memory type). All chains were stretched upon to exert 150 g force and then force degradation rate in 6 time duration
(1, 3, 24 hours and 3, 7, 21 days) and modulus of elasticity (MOE) in 2 time duration (start and 21 days) were investigated. All Data were analyzed statistically by ANOVA, Tukey, Games-Howel tests.
Results: All chains up to the 21th day showed a significant decrease in MOE except for the G&H, ClassOne, simple orthotechnology and a significant force degradation except for the American (memory type). The most significant force degradation rate was in ASTAR gray (P<0.05) and the least in MIB (French), Ultra Chain, and American (P<0.05).
Conclusion: All chains showed significant time-dependent force degradation (mostly in the first day). Only, this rate was not significant in any time duration for the American (memory). In all groups, the most force degradation rate belonged to ASTAR gray and the least to Ultra Chain, MIB (French) and American after 21th day.
Pedram Abedi, Maysam Mirzaee, Sahba Amini, Mohammad Mehdi Naghibi Sistani,
Volume 33, Issue 4 (1-2021)
Abstract
Background and Aims: Information collection about the malocclusion and oral health in blind children is essential to plan for their education in schools. Therefore, this study aimed to evaluate the status of malocclusion and oral health among blind children and teenagers in Mazandaran, Iran.
Materials and Methods: The population of this included 150 blind children and teenagers aged from 10 to 18 years who were referred to the public and private centers cities including Sari, Babol, Freydoonkenar, and Babolsar in Mazandaran, Iran in 2019. Information on maxillary occlusion status, oral hygiene index, and DMFT index was extracted through clinical examination. Data were analyzed using SPSS23 software by ANOVA and Chi-square tests in addition to the descriptive statistics.
Results: The mean DMFT was 10.25 (SD 4.67). Oral hygiene status was good in 16% of participants, moderate in 82%, and poor in 2%. There was no significant difference between girls and boys in terms of oral hygiene status (P=0.5). In all cases, 35.8% had class I malocclusion, 29.8% had class II malocclusion, and 14.6% had class III malocclusion. Class II malocclusion was more common in girls and class I in boys (P=0.01).
Conclusion: Dental caries and occlusal abnormalities were common among blind children and adolescents living in Mazandaran province. Addressing the oral and dental needs of the blind should be a priority for health policymakers in this province in Iran.
Amineh Ghaznavy, Ahmad Reza Talaeipour, Mehdi Vatanpour, Amir Abbas Moshari,
Volume 33, Issue 4 (1-2021)
Abstract
Background and Aims: Pulpal exposures originated from the external cervical root resorptions have major effects on the treatment and prognosis. Therefore, the aim of this study was performed to compare the two different imaging systems-digital radiography with PSP (Photostimulable Phosphor) sensor in three horizontal different views and CBCT (cone beam computed tomography) images to assess the pulpal exposure in simulated cavity of external cervical root resorptions that was performed in 1398 in the School of Dentistry of Azad University.
Materials and Methods: 40 intact maxilla anterior teeth with straight roots were included. Teeth were randomly divided to two groups (20 teeth with and 20 without pulpal exposures). Each sample was assessed using PSP digital radiography (in 3 horizontal angles) and CBCT image system, to detect the presence of pulpal exposures. False negative and false positive results in 2 imaging procedures were judged with ratio test.
Results: The results showed in CBCT (P.P.V=85.7%) and (N.P.V=89.5%), and in digital intraoral radiography (P.P.V=80%) and (N.P.V=80%) in proximal defects. Ratio test showed that there were no significant differences in the proximal defects (P<0.4).
Conclusion: The results showed that there were no significant differences in detection of exposure in the proximal surfaces between two imaging systems.
Marzie Mazhari, Ali Habibikia, Ali Badfar, Mehdi Sabaghian, Arash Dabbaghi, Fattaneh Ghorbani Javadpour,
Volume 35, Issue 0 (5-2022)
Abstract
Background and Aims: By using the image processing capability in Cone-Beam Computed Tomography (CBCT), obtained information can be improved. The aim of the present study was to investigate the effect of sharpen image processing filter in determining the external resorption of the root apical region in single-rooted teeth due to the proximity of the impacted tooth using CBCT.
Materials and Methods: In this laboratory study, the lateral surfaces of the apical region of the root of 40 healthy extracted teeth were artificially cut by bur and the teeth were randomly divided into four groups: control, low, moderate, and high resorption. After preparing CBCT of the teeth, the samples were then processed with and without an image sharpening processing filter and examined by two observers. The results of this study were analyzed by SPSS22 and Medcalc Statistical Software version 14. The significance level was considered P≤0.05 for all the statistical tests.
Results: Specificity (100%) and sensitivity (66%>) were either complete or very high for both modes without and with the sharpen filter. The overall accuracy (0.83>) was high in both cases and no significant difference was observed between the two overall accuracies (P>0.05). Statistical analysis of both image observations by two observers showed that the overall sensitivity and accuracy in the medium and high resorption groups was much higher than the low resorption group, but the specificity in all groups was 100%.
Conclusion: The results showed that the images with a sharpening filter did not increase the detection power compared to the unfiltered images. However, as no loss of accuracy was observed with this filter, it could be used as a processing filter.
Mehrdad Kahvand, Mostafa Vahedian, Mansoureh Hadadzadeh, Ali Saleh, Aida Mehdipour,
Volume 36, Issue 0 (5-2023)
Abstract
Background and Aims: One of the concerns of dentists is selecting a suitable brand of stainless steel crowns with maximum dimensional adaptation with primary teeth. The aim of this study was to compare the primary molar crown dimensions with that of two brands of stainless steel crowns (SSCs) in a sample of Iranian children.
Materials and Methods: In this study, 130 eligible children between 3 and 12 years (66 boys, 64 girls) were selected. After recording the demographic information, the mesiodistal, buccolingual and occluso-gingival dimensions of first (D) and second (E) primary molars were measured on dental casts and compared with the dimensions of KTR (MeiMeiMinBenjing, Benjing, China) and Shinghung (Shinhungcompany, Seoul, South Korea) SSCs. Data were assessed using chi-square test and Pearson correlation coefficient. P<0.05 was considered statistically significant.
Results: In this study, the most dimension matching of the teeth with that of SSCs were observed mesiodistally in upper D and lower D, buccolingualy in the upper D and lower D, and occluso-gingivaly in upper D and lower E. The most cases of mismatch in the mesiodistal dimensions of the teeth with that of SSCs were observed in the lower E and upper D. Also, the most cases of mismatch in the buccolingual dimension were found for upper E and lower E.
Conclusion: Both SSCs brands in this study showed significant dimensional adaptation with the primary teeth in Iranian children. The most dimensional adaptation was between KTR SSCs and maxillary primary molars, and between Shinhung SSCs and mandibular primary molars.
Shahin Shams, Alireza Sharifinejad, Ali Saleh, Pedram Mahmoodi, Abolfazl Mohammadbeigi, Mohammad Mehdizadeh,
Volume 36, Issue 0 (5-2023)
Abstract
Background and Aims: Management of pain and inflammation after third molar surgery is an important challenge of this treatment. Various medications have been proposed for pain control after surgery. Comparing the effectiveness of various drugs used in this field can improve dentists' clinical decisions. The aim of this study was to compare the effect of Ketorolac and Gelofen on pain relief in patients undergoing third molar surgery.
Materials and Methods: This randomized single-blinded clinical trial was performed on 140 patients who were divided into two groups of 70 after receiving the ethical code. The first group was prescribed 400 mg Gelofen capsule for 1 week, while the second group was prescribed 30 mg ketorolac ampule for 1 week. Then, using the visual analog scale (VAS), the patient’s pain was recorded 48 hours, 1 week, and 2 weeks after surgery. Data analysis was carried out using SPSS20 software by descriptive analysis of the results. Ki-square, T-test, and variance analysis were also used for analysis of variables.
Results: The pain level in the ketorolac group after 48 hours, 1 week, and 2 weeks following surgery was significantly less than Gelofen group (P<0.01). Ketorolac effect on pain was irrelevant to the gender, age, and type of tooth variables.
Conclusion: From the results, it was concluded that Ketorolac had greater effect on pain relief after third molar surgery than Gelofen.
Mehdi Rahjoo, Bahareh Tahani,
Volume 37, Issue 0 (3-2024)
Abstract
Background and Aims: One of the most important consequences of the rapid growth of urbanization has been the unequal distribution of urban service specially health care services and escalation of social inequality of citizens. Therefore, this study was aimed to analyze the spatial distribution of dental centers in Isfahan from the perspective of spatial equity.
Materials and Methods: This analytical cross-sectional study was conducted in 2023 in Isfahan city. The required data including the population of the fifteen districts of Isfahan city, the data of the geographic municipal areas and the dental centers of Isfahan city were put into Excell. The population data were gathered from the statistical yearbook of population and housing. The dentists’ data were gathered from the Medical Council. Addresses of the dental centers were fed into the Google earth and were found on the traffic map of Isfahan. Using the Arc GIS 10.8 software and based on the Geographic Information System concepts, the spatial justice was analyzed. Moran's autocorrelation index was used to determine the distribution pattern (cluster, scattered, random). Hot spot analysis and nearest neighbor distance (centers in this radius would have more access) were used. Access ratios were analyzed using the ratio of population to the distance of each parcel to the dental centers and then were categorized as privileged to, semi and unprivileged.
Results: Z-score of Moran test was more than the expected score of 2.58 at 0.01 level of significant, indicating the cluster pattern of dental settings distribution in Isfahan. Moran's index (0.076) was much more than the expected equity coefficient (-0.000055), indicating again the cluster pattern of distribution which was not favorable in terms of spatial justice. The nearest neighbor distance analysis indicated that by moving from the center of the city to the outskirts of the city, access to dental centers decreased. Access analysis determined that privilege areas of the city were located mostly in central municipal areas and about 60% of these areas were limited to three municipal regions. Also, about 63% of the city area were categorized as unprivileged.
Conclusion: Distribution of dental centers in the city of Isfahan is not an equal distribution and the dental settings are mostly concentrated in the central areas of the city, not necessarily in high populated areas. There, this pattern necessitates the proper planning to establish dental settings in deprived and high-populated parts of the city.
Elahe Soltanmohamadi Borujeni, Ali Bavi, Mohammad Aghaali, Ali Saleh, Aida Mehdipour,
Volume 37, Issue 0 (3-2024)
Abstract
Background and Aims: Strong bond between the ceramic brackets and ceramic veneers has an important role in cosmetic treatment. The purpose of this study was to investigate the effect of aging on the shear bond strength (SBS) of ceramic brackets bonded to zirconia after surface preparation by Neodymium-doped Yttrium Aluminum Garnet (Nd: YAG) laser or sandblasting with alumina.
Materials and Methods: This experimental study was conducted on 24 zirconia blocks and these blocks were randomly divided into two groups for surface preparation and each was sub-divided into three time intervals. Surface preparation was done by sandblasting with alumina: in SG1 (Immediately after sandblasting), SG2 (2 weeks after sandblasting), and SG3 (3 months after sandblasting) groups. For the Nd: YAG laser (1/5W, 20Hz, 10s) with non-contact mode: in LG4 (Immediately after laser), LG5 (2 weeks after laser), and LG6 (3 months after laser) groups. The ceramic brackets were bonded to the zirconia blocks. The SBS and adhesive remnant index (ARI) were evaluated and compared among test groups. Dara were analyzed using Mann Whitney test.
Results: There was no significant difference between the SBS of SG1 and LG4 (P=0.430), SG2 and LG5 (P=0.382) and SG3 and LG6 (P=0.326) groups. LG4 group showed the highest shear bond strength. After aging (2 weeks and 3 months), the laser groups showed higher SBS. There was no significant difference in the ARI between SG1 and LG4 (P=0.220), SG2 and LG5 (P=0.154), SG3 and LG6 (P=0.527) groups.
Conclusion: No significant difference was observed between the Nd: YAG laser and sandblasted groups in terms of SBS and ARI over time. Therefore, Nd: YAG laser could be used as a surface treamnet method in Zirconia crowns for bonding to ceramic brackets.
