Showing 87 results for Age
Hamid Kermanshah, Esmaiel Yasini, Razieh Hoseinifar,
Volume 26, Issue 1 (3-2013)
Abstract
Background and Aims: Marginal seal in class V cavity and determination of the best restorative material in reducing microleakage is of great concern in operative dentistry. The aim of this study was to evaluate the effect of load cycling on the microleakage of low shrinkage composites compared with methacrylate-based composites with low shirinkage rate in class V cavity preparation. Marginal integrity of these materials was assessed using scanning electron microscope (SEM).
Materials and Methods: In this in vitro study, class V cavity preparations were made on the buccal and lingual surfaces of 48 human premolars and molars (96 cavities). The specimens were divided into four groups each containing 12 teeth (24 cavities): group 1 (Kalore-GC+ G-Bond) , group 2 (Futurabond NR+Grandio), group 3 (All Bond SE+ Aelite LS Posterior), group 4 (LS System Adhesive Primer & Bond+Filtek P90). All the specimens were thermocycled for 2000 cycles (5-50oC). In each group, half of the specimens (n=12) were subjected to 200,000 cycles of loading at 80 N. Epoxy resin replicas of 32 specimens (4 restorations in each subgroup) were evaluated using SEM and the interfacial gaps were measured. Finally, the teeth were immersed in 0.5% basic fuchsin dye for 24 hours at 370C, then sectioned and observed under stereomicroscope. The data were analyzed using Kruskal-Wallis and Mann-Whitney U tests and the comparison between occlusal and gingival microleakage was made with Wilcoxon test.
Results: Within unloaded or loaded specimens, there were no significant differences in microleakage among four groups on the occlusal margins (P>0.05). But there were statistically significant differences in microleakage between silorane and Aelite on the gingival margins (P<0.05). No statistically significant differences were found between the microleakage of the loaded and unloaded groups on both occlusal and gingival margins for all materials (P>0.05).
Conclusion: Silorane did not perform better than the conventional low shrinkage methacrylate-based composite in terms of sealing ability (except Aelite). Cyclic loading did not increase the extent of leakage in any groups.
Salari Behzad , Shahabi Sima , Bagheri Hossein , Yousefi Mahsa ,
Volume 26, Issue 4 (1-2014)
Abstract
Background and Aims : The aim of this study was to evaluate the effect of chlorhexidin 2%, sodium hypochlorite 2.5% and hydrogen peroxide 3% as three effective and regular disinfectants on the microleakage of 7th generation bonding agents in vitro.
Materials and Methods: 45 extracted molar teeth without carries were collected and disinfected. On buccal and lingual aspects of these teeth conventional class V cavity preparation were done (90 cavities), then randomly divided to 4 groups, three of them had 10 teeth (20 cavities) and one of them had 5 teeth (10 cavities) as control group. Cavities in each experimental group prepared with one of the disinfectants and then 7th generation bonding (Optibond all in one, kerr) was used as noted by manufacturer, then cavities filled with composite and polished. Bonding agent was used without our previous disinfectants manipulation in control group. Specimens were thermocycled with 1000 thermal cycles between 5 and 55 0 C each for 30 seconds and then immersed in the methylene blue 5%, then sectioned mesiodistally and investigated for microleakage under stereomicroscope (Olympus, Japan). Data were analyzed using Kruskal-Wallis and Wilcoxon mean rank tests.
Results: Despite the lower mean rank values for the untreated group at both occlusal and gingival aspects, the Kruskal-Wallis procedure (α=0.05) showed that the treatment factor did not significantly affect the mean rank values neither in occlusal (P=0.12) nor in gingival (P=0.39) part of cavities.
Conclusion: According to the results of this study, antimicrobial agents such as chlorhexidine 2%, sodium hypochloride 2.5% and hydrogen peroxide 3% can be used perior to 7th generation dentin bonding agent
(Optibond all in one, kerr) without much concern.
Jalil Modaresi, Vahid Shirani, Mohammad Malekzadeh,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims: Electric pulp tester is a valuable instrument to examine tooth’s pulp vitality. There is no agreement about the response of immature teeth to electric pulp tester and the reason is expressed as the failure of nerve fibers’ development. The aim of this study was to investigate the effect of patient’s age on the tooth response to electric pulp tester.
Materials and Methods: In this cross-sectional study, 300 maxillary central permanent teeth in 150 volunteers were examined by using electric pulp tester. The volunteers were classified in 5 age groups of 7-8, 9-10, 11-12, 13-4, and 30-35 and teeth lacking sound and healthy pulp were excluded. Data were analyzed using SPSS-16 software, one-way analysis of variance, and Tukey post hoc test.
Results: The average response to electric pulp tester in age groups of 7-8, 9-10, 11-12, 13-4, and 30-35 years old were 2.9±0.1, 2.8±0.1, 2.3±0.1, 2.2±0.1 and 1.8±0.1 ,respectively. This indicated that by increasing teeth age, they responded to lower level of electric pulp tester. In subjects less than 14 years old, there was no significant difference between neighboring groups (P=0.3) however, a significant difference was observed between subjects less than 14 years old and adults (P<0.001).
Conclusion: This study showed that immature teeth responded at higher levels to electric test however, all teeth responded to electric pulp tester.
Seyed Amir Hossein Mirhashemi, Razieh Jabbarian,
Volume 27, Issue 2 (6-2014)
Abstract
The need to identify and determine the age of the unidentified dead person s or accident victims of natural disasters is clear. Also, some remedial measures in the field of orthodontics and pediatric dentistry depend on knowing the patient’s physiological age. Previous studies suggested that dental age have a good correlation with physiological age more than skeletal or o ther common methods of age determination. Among the various methods used to determine dental age , dental radiography provides wide facilities for clinicians. Being noninvasive and the ability of performing the technique on live subjects as well as simplicity and low cost and reliable results , have led researchers to investigate further on that . The formation and calcification process of teeth and changes during aging has been regarded by many, leading to introduce various methods in which the field. In this study, 36 related articles were achieved by searching PUBMED, Science Direct and Google Scholar resources and discussed. Provided what diversified means of determining age using dental radiographs is encouraged , it is recommended to be not restricted to use only one of the methods because the multilateral approach is more reliable.
Baharan Ranjbar Omidi, Ladan Madani, Aida Mirnejad Joybari, Ensyeh Rashvand, Sonia Oveisi,
Volume 28, Issue 2 (7-2015)
Abstract
Background and Aims: Microleakage is an important problem with direct restorations and familiarity with contributing factors is of utmost importance. The aim of this study was to evaluate the microleakage of three glass ionomer restorations in class V cavities.
Materials and Methods: In this in vitro study, class V cavity preparations were made on the buccal and lingual/ palatal surfaces of 30 human premolars (60 cavities). The specimens were divided into three group (n=10, 20 cavities). Restored as follows: group1: with Fuji IX (HVGI) ionomer/G coat plus, group 2: Ionofil molar (HVGI)/ G coat plus, and group 3: Fuji II LC (RMGI) / G coat plus. All specimens were finished and polished immediately and were thermocycled (2000 cycles, 5-50°C) . In each group half of the teeth were load cycled (50000 cycles). Finally, the teeth were immersed in 0.15% basic fushine dye for 24 hours at room temperature and then sectioned and observed under stereomicroscope. Data were analyzed using Kruskal-Wallis, Man- Whitney test and a comparison between incisal and gingival microleakage was made using Wilcoxon analysis.
Results: It was shown that the mechanical load cycling and filling material did not cause a statistically significant increase in the incisal and gingival microleakage in any of groups (P>0.05).
Conclusion: It was concluded that the extent microleakage of Fuji II LC was similar to that of the highly viscous glass ionomers (Ionofil molar, Fuji IX) and load cycling did not increase the microleakage.
Fatemeh Mokhtari, Marzyeh Mirzaei,
Volume 28, Issue 3 (10-2015)
Abstract
Background and Aims: Inadequate root canal obstruction has been suggested as major factor in endodontic treatment failure. On the other hand, the most common way to assess leakage is dye penetration method. In assessing the possible effect of cutting direction on the leakage, the present study was performed to investigate dye penetration in two root cutting directions.
Materials and Methods: Forty human teeth with a single root canal were used in this experimental study. Endodontic treatment was performed on the specimens and then stained with 2% methylene blue solution. The specimens were divided into two groups. Specimens in the first group were sectioned in the buccolingual dimension and the second group in the mesiodistal to evaluate the microleakage. The amount of dye penetration was measured under the stereomicroscope with a magnification of 40%. Data were statistically analyzed using Kolmogorov-Smirnov (KS) and Mann- Whitney tests.
Results: The average amount of leakage in the buccolingual and mesiodistal dimension were, 3.78±2.08 and 2.43±1.55 mm, respectively. There was statistically significant difference between the mean leakage of two dimensions (P=0.03).
Conclusion: Since the leakages in the buccolingual and mesiodistal dimensions were different, it was concluded that cutting direction could be an effective factor on the result of microleakage assessment.
Mansore Mirzaie, Esmaiel Yasini, Ladan Ranjbar Omrani, Morteza Rokni, Hojat Darvishpour ,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: Microleakage is a criterion proposed for assessing the success of any restorative material. Complete seal is difficult especially for dentin margins compared to enamel margins. The aim of this study was to assess the microleakage at the enamel and dentin margins of class V cavities restored by two GIs and two self-etch adhesive systems.
Materials and Methods: This study was done on forty third molars. Class V cavities (3×2×2mm) were prepared on the buccal and lingual surfaces of teeth using high speed handpiece with 0.8 mm diamond fissure burr. The occlusal margins of the cavities in the enamel and gingival margins were placed 1 mm below the CEJ. The teeth were divided into 4 groups and the bondings were cured for 20 sec and the teeth were restored. The specimens were kept in distilled water at the temperature of 37°C for 24 hrs. The teeth were thermo cycled and cut in buccolingual direction using diamond disc under water. The dye penetration was evaluated using a stereomicroscope and the leakage was scored. The scores were compared using Kruskal-Wallis test while the paired comparisons were done using Bonferroni correction. P≤0.05 was regarded as significant results.
Results: Microleakage scores were similar at the occlusal and gingival walls of all test groups. At the gingival walls, the least microleakage scores were observed. “Fuji IX + SE bond” group showed significant differences with the “Fuji IX + G bond” and “Nanoglass + G bond” groups (P≤0.05). At the occlusal walls, the least scores were observed in the “Fuji IX+SE bond” specimens which were significantly different from the other groups (P≤0.05).
Conclusion: Self-Cure glass ionomers yielded less microleakage scores compared to the different types of light-cures due to the less polymerization shrinkage.
Mostafa Ghandi, Babak Namvar, Sotodeh Davaie,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: As in fissure sealant therapy the tooth surface is mostly enamel, the use of an enamel bonding agent (hydrophobic bonding agent) may be more cost effective than that of newer generations of bonding (hydrophilic bonding agents). The aim of this study was to compare the retention and durability of fissure sealant therapy when applying an enamel bonding agent, a dentin bonding agent and no bonding agent during 4 years.
Materials and Methods: This study was done on the first permanent molars of the upper and lower jaws of 24 students of the first grade of a primary school (6-7 years old). On 36 teeth, a dentin bonding agent (Excite) was applied under the fissure sealant and on 36 teeth an enamel bonding agent (Margin bond) was applied under the fissure sealant. Then, 24 teeth were selected from these two groups and were compared with a group (including 24 teeth) with no bonding agent under the fissure sealant (as control group). All the fissures of the teeth were evaluated annually for 4 years to find out the presence or absence of fissure sealant substance. Data were analyzed using Wilcoxon test.
Results: From the statistical analysis, there was no significant difference in retention and durability of the fissure sealant substance comparing the group with dentin bonding agent (Excite) and the group with enamel bonding agent (Margin bond). Also, using a bonding agent made no significant difference (P>0.05).
Conclusion: According to the results of this study, using a bonding agent made no improvement in the retention and durability of fissure sealant substance.
Nasrollah Jabbari, Seyyed Reza Mousavi, Kamal Firoozi,
Volume 28, Issue 4 (1-2016)
Abstract
Background and Aims: With the increasing use of CT (Computed Tomoghraphy) scans in dentistry especially in the implantology, there may be significant increases in the radiation exposure and its risk. During the last year’s ConeBeam Computed Tomoghraphy (CBCT) has been introduced as an imaging modality for dentistry. The aim of this review article was to present comprehensive information have been published, regarding the radiation dose and image quality of Conventional Multislice Computed Tomography (MSCT), Cone-Beam CT (CBCT) and periapical radiography in dentistry imaging.
Materials and Methods: A review of the literature was carried out in PubMed, Google Scholar, Science Direct and Scopus database using key words (CBCT, MSCT, periapical radiography, radiation dose of dentistry and image quality). These searches were limited to the articles published between the years of 1993 to 2015.
Conclusion: In comparison to MSCT, CBCT had a short scanning times and lower radiation dose, but in comparison to periapical radiography, CBCT had higher radiation dose. In contrast, CBCT with flat panel detector had higher spatial resolution to MSCT. The periapical radiography also had a good image contrast and relatively high resolution. Generally, CBCT was suitable for hard tissue imaging and MSCT was preferred for soft tissue imaging.
Saeed Nemati Anaraki, Hamed Karkehabadi, Nazanin Zeinab Garshasb Zadeh,
Volume 29, Issue 1 (7-2016)
Abstract
Background and Aims: Microleakage is one of the most common problems in bonding systems, which cause different clinical shortcomings such as post operative sensitivity, marginal discoloration and pulp necrosis that can decrease those using bonding systems. The aim of this study was to compare the microleakage of three self etch bonding agents (generation 6 and 7) in class 5 composite cavities.
Materials and Methods: In this experimental study, 30 facial class 5 cavities were prepared in 30 human premolar teeth which were freshly extracted for orthodontic purposes. Cl V cavities were prepared in 2*3*2 mm dimensions. Occlusal margins were in enamel and gingival ones in cementum and randomly divided into 3 groups of 10 each. Then the cavities were treated by clearhil SE Bond (Kuraray, Japan), G Bond (GC, Japan), and Opti Bond Solo Plus (Kerr, USA), according to the manufacturers’ insductions. Then the cavities were filled using Z100 resin composite. The specimens were then immersed in a 50% AgNo solution for 24 hrs. Then, the teeth were cut buccolingually to be evaluated for dye penetration with stereomicroscope. Data were analyzed using Kruskal-Wallis test.
Results: This study revealed that Opti bond solo plus had type1 microleakage (dye penetration up to 1/3 of cavity) in 80% of specimen, and type 4 microleakage (along axial wall) in 10%. Clearfil SE bond had no leakage in 50%, type1 in 40% and type 2 (up to 2/3 of cavity) in 10%. But there was no significant difference in the microleakage at the gingival margins between 3 groups (P>0.05).
Conclusion: Clearfil SE Bond and G bond could prevent microleakage more effectively than that of Opti Bond Solo Plus on the occlusal margins. However, no difference in the microleakage on the gingival surfaces was found.
Mohammad Ali Keshvad, Tabassom Hooshmand,
Volume 29, Issue 2 (11-2016)
Abstract
Resin-based composite restorative materials have a substantial share in dental treatments. Their esthetic has made them patients’ first choice as restorative materials. Marginal leakage is one of their problems which leads to recurrent caries and post-operative hypersensitivity. Our aim was to evaluate the theoretical and clinical methods that have been proposed in the dental literature. Around 50 articles from Pubmed, SCOPUS and google scholar were selected and categorized in 4 groups based on the selected keywords. All the studies discussed in this paper have emphasized that there is no way to eliminate the microleakage but it can be reduced by means of some approaches. On the other hand, due to the multifactorial nature and difference of oral environment and laboratory conditions, there isn’t any certain way to define precisely. It seems that there is an absolute need for more research in this field to make the relation of theoretical results and clinical findings possible.
Behrad Tanbakuchi, Sepideh Arab,
Volume 29, Issue 3 (10-2016)
Abstract
Background and Aims: The first permanent molar is susceptible to caries, endodontic complications and developmental anomalies. Compromised teeth with poor prognosis could cause the clinician to face dilemmas. The aim of this review article was to assess recent guidelines on the treatment planning of compromised first permanent molars in mixed dentition period.
Materials and Methods: The design of the study was based on review of literature by searching the MEDLINE, Web of science and Google scholar. Key words (permanent first molar, extraction, treatment plan) were used. This search was limited to the English articles published after the year 2000.
Conclusion: A number of factors influenced decision-making process regarding compromised first permanent molars including the restorative status of the tooth, dental age of the patient, degree of crowding and occlusal relationships were assessed. The ideal time for removal of these teeth was 8-9 years of age. However, the current evidence for managing compromised first permanent molars demands clinical trials.
Esmail Yassini, Mansoureh Mirzaei, Bahar Safaei Yazdi, Zohreh Moradi,
Volume 30, Issue 3 (10-2017)
Abstract
Background and Aims: One of the main disadvantages of light cured composite resin materials is polymerization shrinkage upon curing. This leads to the microleakage of restoration and finally failure of the restoration. The purpose of this study was to investigate the effect of two types of light curing devices with different modes on the microleakage of posterior composite filling in Cl II restorations.
Materials and Methods: In this experimental study, 30 extracted sound molar human teeth were collected. All specimens were randomly divided into 3 groups of ten: Standard LED irradiation, pulse curing LED irradiation and QTH irradiation. All samples were prepared with mesial and distal boxes and composite fillings were done with three different light curing patterns for 20 s. After thermocycling, the specimens were kept in 2% methylene Blue solution for 24 h for microleakage test. After sectioning, the samples were evaluated by a stereomicroscope. For data analysis one-way ANOVA and Kolmogorov-Smirnov were used. P<0.05 was considered statistically significant.
Results: The quantitative tests showed that there were no statistical difference between study groups (P>0.05).
Conclusion: The results showed that both light curing devices were effective and no significant difference between different modes of LED light curing device on microleakage of class II composite restorations was found.
Fatemeh Mokhtari , Kazem Koopaei, Jalil Modaresi, Hamid Reza Hemati, Hengameh Zandi,
Volume 30, Issue 3 (10-2017)
Abstract
Background and Aims: The purpose of this study was to evaluate the sealing ability of MTA and cold ceramic by using bacterial leakage method.
Materials and Methods: In this experimental study, fifty human single root extracted teeth were chosen. In group A, 20 teeth were filled with MTA and in group B, 20 teeth were filled with cold ceramic. Five teeth were used as a positive control (obturated using gutta-percha without sealer), and five teeth were used as negative control (obturated using gutta-percha with AH26 sealer and coated with two layers of nail varnish). A bacterial leakage model utilizing Enterococcus faecalis was used for evaluation of the sealing ability. The teeth were placed in test tubes, so that they formed two upper and lower compartments. The cultured bacteria in the upper chamber were in contact with the coronal area of the tooth. The root end was placed in the lower chamber containing sterile culture media. In this case, the filling of the root canal was only the communication path between the upper and lower chambers. In this method, the presence of turbidity in the lower chamber indicated that bacteria had penetrated through barrier and reached the medium. The leakage was measured. The acquired data was analyzed using Chi-square test.
Results: In group A (MTA), 7 samples and in group B (Cold ceramic), 4 samples should the leakage. In regarding the leakage, there was no statistically significant difference between MTA and cold ceramic. (P=0.288)
Conclusion: The results showed that the sealing ability of MTA and cold ceramic was similar as root filling materials.
Abdolrahim Davari, Alireza Danesh Kazemi, Mehrrnaz Fallah Tafti,
Volume 30, Issue 4 (1-2018)
Abstract
Background and Aims: A suitable restorative material must have acceptable mechanical properties. The aim of this study was to evaluate the effect of conventional acidic drinks on the micro-hardness of two dental resins.
Materials and Methods: 48 samples of each of P60 and G-aenial composites were prepared and randomly divided into six groups: Coca-Cola, Fanta, yoghurt drinks, soft beer, Sprites and control groups. The study was in 3 steps: after one day in distilled water and after one day and one week of immersion in beverages per day
(6 hours). The Vickers micro-hardness was then evaluated. Finally, data were analyzed by, t-tests, ANOVA and Tukey tests.
Resultes: Comparing the results between the two groups, a significant difference between the two composite was found. After one day in the water, the average micro-hardness for P60 was of 27.12 (kgf/mm2) and 16.51 (kgf/mm2) for G-aenial amount and these differences were found statistically significant (P=0.0001). For the
6-hour maintenance interval, the average micro-hardness between P60 and G-aenial was statistically significant (P=0.0001). For 42 hours, the average micro-hardness ranged between P60 and G-aenial that were statistically significant (P=0.0004). The stiffness of the P60 composite after 42 hours’ storage in soft beer significantly decreased compared with the control group (P=0.03). G-aenial composite hardness after 42 hours of soaking in the Coca-Cola was reduced significantly compared to yogurt drinks (P=0.02).
Conclusion: As a result, the hardness of P60 composite was higher than that of G-aenial. The hardness of both composites reduced in acidic drinks after one week.
Abbasali Khademi, Seyed Amir Mousavi, Azizolah Moraditalab, Shirin Shahnaseri, Saber Khazaei, Reyhaneh Tajali,
Volume 31, Issue 1 (6-2018)
Abstract
Background and Aims: Microorganisms are the main cause of pulpal and periapical diseases. The most important failure factor is the lack of proper seals for the canal, resulting in microbial leakage. Therefore, the purpose of this study was to evaluate the sealing ability of ProRoot MTA and Bio MTA in canal obturation using fluid infiltration.
Materials and Methods: In this experimental study, 46 extracted mandibular premolar single canal teeth were used. After preparing and disinfecting the teeth with 3% sodium hypochlorite, their crowns were cut off from the cement-enamel junction. The teeth were then randomly divided into four groups: Group 1 (n=20) Bio MTA, Group 2 MTA ProRoot (n=20), negative and positive control groups, each of them contained 3 teeth. The preparation of teeth was performed using the step back method. The filled teeth were then evaluated by fluid filtration for leakage prevention. Data were analyzed by Mann-Whitney test and Tukey test (α=0.05).
Results: The results of statistical analysis showed that there was no significant difference between the MTA ProRoot and Bio MTA in sealing ability (P>0.05). That micro leakage is less in the Bio MTA group than in the ProRoot MTA group, but the difference was not significant.
Conclusion: This study showed that MTA ProRoot and Bio MTA can be used as appropriate canal filling materials.
Mohammad Javad Moghadas, Ehsan Rohani, Sara Majidinia, Najmeh Ojrati, Negin Vatanparast,
Volume 31, Issue 4 (1-2019)
Abstract
Background and Aims: The aim of the present study was to evaluate the effect of applying hydrophobic resin after use of different generation of the bonding systems on nanoleakage.
Materials and Methods: 20 third molar teeth were selected. The teeth were randomly divided into 4 groups of 5, each was treated using the fourth, fifth, sixth, and seven generation of dentin bonding. Then, the crown of teeth was sectioned from the CEJ region and each specimen was divided into two halves with mesiodistal cut, one half for the application of dentin bonding without the addition of a hydrophobic resin, and the other for the same dentin bonding by the addition of a hydrophobic resin. Afterwards, the specimens were restotred by composites. After placement of specimens in silver nitrate, the amount of nanoleakage was evaluated by SEM. Data were analyzed using a repeated measurement statistical analysis (α=0.05).
Results: The use of hydrophobic resins decreased nanoleakage and range of variations in all groups (P<0.05). This reduction was greater for total-etch dentin bonding. Higher degree of nanoleakage occurred in total-etch dentin bonding in most evaluated areas. In general, Clearfil S³ bond showed the least percent of the nanoleakage.
Conclusion: All dentin bonding systems showed some degree of reduction in nanoleakage after hydrophobic layer application and the reduction was greater in Total-etch adhesives systems.
Azadeh Zakerzadeh, Abdolrahim Davari, Haleh Karami,
Volume 33, Issue 2 (8-2020)
Abstract
Background and Aims: The self-adhering composites were introduced to reduce the chair time and minimizing handling errors. They can be bonded micromechanically to the dental structure without the need for separate adhesive application. Since there is limited information about bonding performance of this type of composite, the aim of this study was to evaluate the microleakage of enamel and dentin margins compared to the conventional adhesive systems.
Materials and Methods: 30 intact premolars were selected and on their buccal and lingual surfaces, standardized class V cavities with the occlusal margin in enamel and gingival margin in dentin were prepared. Then according to the materials used, the specimens were randomly divided into three groups including: 1) Vertise flow, 2) SE bond + ValuxTM Plus, and 3) Single bond + ValuxTM Plus. After final polishing of the restorations, the specimens were subjected to 1000 thermal cycles of 5±2 and 55±2°C and after that dye penetration was examined by stereomicroscope. The collected data were statistically analyzed using Kruskal-Wallis test and Mann-Whitney test
Results: The lowest rate of the occlosal microleakage was related to group 2 (P<0.05) and there was no significant difference between groups 1and 3 (P=0.58). Also, no significant difference was found in the gingival microleakage among the three groups (P=0.23). On the other hand, in each group, the gingival microleakage was significantly higher than occlosal margins (P<0.05).
Conclusion: According to the results, sealing ability of self-adhering composite is comparable with that of the conventional adhesives.
Alireza Daneshkazemi, Abdolrahim Davari, Zahra Usefi, Niloofar Fallah, Solmaz Ghanbarnejad, Pedram Daneshkazemi,
Volume 33, Issue 3 (10-2020)
Abstract
Background and Aims: Adding nanoparticles to dental composite resins, could reduce bacterial adhesion and secondary caries. Thermocycling can resemble in-vitro conditions to the oral environment. The aim of this study was to determine the effect of thermocycling on the microleakage of a mixture of copper oxide nanoparticles and flowable composite.
Materials and Methods: In this in-vitro study, 88 premolar teeth were divided into eight groups based on the application of copper oxide nanoparticles with concentrations of 0.1% and 0.3% w/w and thermocycling by 0, 1000, 5000 and 15,000 cycles. The occlusal grooves of the teeth were sealed with the mixture of flowable composite and copper oxide nanoparticles, and the teeth were thermocycled. Next, the teeth were immersed in methylene blue 2% solution for 24 hrs and were cut and the microleakage was evaluated by a stereomicroscope (hp/USA). Data were analyzed using Kruskal-Wallis and Mann-Whitney tests at the significance level of 0.05.
Results: In the groups with 0.1 % copper oxide nanoparticles, the mean microleakage increased significantly with increasing the number of thermocycling rounds (P=0.032). The difference in the microleakage between the groups exposed to 0 and 15,000 termocycling was significant (P=0.019). However, thermocycling had no significant effect on the microleakage of groups with concentration of 0.3% (P=0.780). The specimens subjected to the 0, 1000, 5000 and 15000 thermocycling in two concentrations of copper oxide nanoparticles showed no significant difference in the microleakage.
Conclusion: In groups containing copper oxide nanoparticles with a concentration of 0.1%, the microleakage increased by increasing the number of thermocycling up to 15,000 cycles compared to the control group. However, this did not have significant effect for the concentration of 0.3% copper oxide nanoparticles.
Reza Sharifi, Mohammad Bayat, Sheida Kordi, Afshin Heidari, Mahbubeh Sadat Hasheminasab,
Volume 34, Issue 0 (5-2021)
Abstract
Background and Aims: This study aimed to collect reports and HIS in a web-based system due to the problems of paper recording of student activities in practical courses, as well as the lack of computers in the departments for observing graphs and treatment plans.
Materials and Methods: The initial graphic design of the website was done after the assessment of needs and the necessary planning for designing the website. The main template of the website was designed after consulting with the faculty and the designer company. A combination of HTML, CSS, JQuery, and Java script was used for static coding and what the user sees or interacts with. Then, the basic information entered the website and the content designer put the website in the designed layout. In the end, a sample hosting space was prepared and the website was fully provided to the professors and faculty officials to work with as an administrator and a user. They conveyed all their opinions and the corrections were made based on the feedback given.
Results: The use of the internet and software with a central database played a significant role in monitoring and evaluating the long-term information of the student and the evaluation of the entire department, universities, and patients in each region up to macro-national evaluations. This could give the expansion and advancement of science in addition to the central registration of documents and radiographs, as well as their ease to access.
Conclusion: The designed website was well received among the students and the attending staff. Introducing a web based logbook and HIS system can optimize the clinical teaching. These logbooks could help both students and staff saving time and resources, and to facilitate providing better personalized care for patients.
