Showing 59 results for Composite
Mansure Mirzaee, Esmaeel Yassini, Sima Shahabi, Nasim Chiniforoush, Naznin Zeinab Garshasbzade,
Volume 27, Issue 1 (4-2014)
Abstract
Background and Aims: Indirect composites are designed to overcome the shortcomings of direct composites such as polymerization shrinkage and low degree of conversion. But, good adhesion of resin cements to indirect composites is still difficult. This research was designed to assess the effect of different powers of ErYAG laser compared with sandblasting. On the micro tensil bond strength of resin cement to indirect composites.
Materials and Methods: Specimens were prepred using dental resin composite (Gradia GC) and metallic mold (15×5×5 mm) and were cured according to the manufacturer’s instructions. 24 blocks were prepared and randomly divided into 12 groups. G1:no treatment (as control), G 2-6: Er YAG laser irradiation (2, 3, 4, 5, 6 Watt), G7: sandblast. Two composite blocks were bonded to each other with Panavia F.2. resin cement. The cylindrical sections with dimensions of 1 mm were tested in a microtensile bond strength tester device using 0.5 mm/min speed until fracture points. Data were analyzed using 2-way ANOVA and T-test.
Results: Interaction between lasers irradiation and sandblast treatments were significant (P<0.05). Thus, T-test was used for comparing laser groups. T-test showed that when using laser with energies less than 150 mJ, there was no significant difference (P>0.05) whether samples were sandblasted or not. Samples which received 300 mJ of laser showed lower bond strength compared with no laser treatment. Other groups showed no significant difference (P>0.05).
Conclusion: It seems that application of sandblast with proper variables, is a good way to improve bond strength.
Laser application had no influence in improving the bond strength between the indirect composite and resin cement.
Narges Dorri, Azita Kaviani, Ali Noori,
Volume 27, Issue 2 (6-2014)
Abstract
Background and Aims: The ability of composite restorations to prevent microleakage needs desirable bonding material for proper sealing . The purpose of this study was to evaluate class V composite restorations microleakage in premolars with/without electric current while applying variant dentin bonding in vitro.
Materials and Methods: 120 non-carious human premolars were used for this study and standardized class v cavities were prepared. The tooth roots were cut by discs at a distance of 5 mm from CEJ and pulp tissue was removed. The teeth were divided into six groups of 20. In the first group, electric current was applied, Single bond (3M ESPE, St Paul, MN, USA) with a broom motion attached to the cathode and a sponge containing bonding was used as anode. The used current was 15µA and the Single bond in the second group was used without electricity. Then two bondings PQ1 (Ultradent, Germany) and Optibond solo plus (Kerr, USA) were used with and without electricity. After adhesive application and curing the bonding agents, cavities were restored by a composite (Valux Plus). The root ends were sealed by wax and all teeth surfaces, except 1 mm around the restorations were covered with a nail varnish. The specimens were thermocycled for 1000 cycles and placed in fushin for 24 hours and were then sectioned vertically and examined under a stereomicroscope. Data were scored on a 0-4 scale based on microleakage at the gingival margins and analyzed using Kruskal-Wallis and Mann-whitney test.
Results: Based on the results, the extent of microleakage in the groups of electric current was significantly less than the groups without using the electric current (P=0.05). The lowest degree of microleakage was found in PQ1 group, and the greatest difference between the groups with and without electricity was also found in PQ1 group. Single bond and Optibond Solo Plus with electric current showed a lower degree of microleakge.
Conclusion: The result showed that use of electric current during the application of dental adhesives could reduce the extent of microleakage.
Davari Abdolrahim , Daneshkazemi Alireza , Modaber Maryam , Malekzadeh Mohammad ,
Volume 27, Issue 4 (1-2015)
Abstract
Background and Aims: The most effective preventing tooth decay method is fluoride compounds applications. Some studies suggested that APF gels caused changes on the superficial physical properties of composite. Therefore, the purpose of this study was to evaluate the marginal microleakage of class V composite restorations before and after AFP gel application.
Materials and Methods: The class V cavities in buccal surfaces of 45 molar teeth were made in such a way that occlusal margin was placed in enamel and cervical margin in cement. In group 1, at first fluoride-therapy and then cavity preparation and restoration by composite resin was done. In group 2, at first the class V cavities were prepared and restored, then fluoride-therapy was carried out. In group 3, cavities were prepared and restored with no fluoride-therapy. The dye penetration rate in occlusal and cervical margins was examined by stereomicroscope. Data were statistically analyzed using Kruskal-Wallis and Mann-Whitney test.
Results: There was no statistically significant difference between groups ( P=0.975).
Conclusion: Fluoride-therapy using AFP gel before and after class V composite restorations, had no significant effect on the microleakage of dentin and enamel margins.
Abdolrahim Davari, Soghra Yassaei, Alireza Daneshkazemi, Mohadeseh Khosravanian,
Volume 28, Issue 2 (7-2015)
Abstract
Background and Aims: Orthodontic bracket failure during treatment is a common problem. With the introduction of low shrinkage composites the question is that whether: this sufficient has coefficient bond strength for bonding bracket during orthodontic treatment. The aim of this study was to compare the shear bond strength (SBS) of silorane-based and metacrylate-based composites to metal brackets.
Materials and Methods: 30 human premolar teeth were collected and divided into 2 groups. In group 1, 15 orthodontic brackets were bonded using silorane-based composite, in group 2, 15 orthodontic brackets were bonded using metacrylate-based composite. The shear bond strength of each specimen was determined in an Instron machine. Amount of residual adhesive remaining on each tooth was evaluated using a stereomicroscope. Data were analyzed using T-test to compare the shear bond strength between groups and LSD method to compare the Adhesive Remnant Index (ARI) scores.
Results: There was significant difference in the SBS between the test groups (P<0.001). The mean bond strength of bonding brackets to silorane-based composite was (42.42 ± 7.03) MPa, and the mean bond strength of bonding brackets metacrylate-based composite was (21.08±2.97 ) MPa. No significant difference in the ART was found between groups (P=0.66).
Conclusion: Silorane-based composite provided higher bond strength to orthodontic metal brackets.
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.
Masumeh Hasani Tabatabaei, Sakineh Arami, Fatemeh Khajavi, Zohreh Moradi,
Volume 29, Issue 4 (1-2017)
Abstract
Background and Aims: Despite the reduction of incidence of dental caries in recent years, this disease is common and many efforts were conducted to decrease the prevalence of dental caries. On the other hand secondary caries lesions are the main reason for replacement of direct restorations. Therefore, the aim of the current study was to evaluate suitable methods of preparation and restorative materials to reduce caries recurrence.
Materials and Methods: In this experimental study, eighty human teeth were collected and stored in normal saline. The teeth were soft-tissue debrided and cleaned with water/pumice slurry and rubber cups in a low-speed handpiece. Speciments were randomly divided in two main groups. Cavities were prepared with diamond burs or Er:YAG laser (10 Hz, 300 mJ, 3W). Each group was divided into 4 sub-groups, and restored with a glass-ionomer cement (Fuji IX), resin modified glass-ionomer (Fuji II LC), total etch bonding + composite resin or self-etch bonding + composite resin. The specimens were submitted to pH cycling. Speciments were then sectioned, polished and Vickers microhardness measurements were performed on each specimen. Differences among the medians were analyzed using two way ANOVA test at a 95% confidence level and Tukey test.
Results: Statistical analysis showed significant difference in the type of substrate (enamel, dentin) in both main groups (P<0.0001) but no differences in the caries lesion development between the cavities restored with the same material and prepared with diamond burs or Er:YAG laser.
Conclusion: The Er:YAG laser used for cavity preparation and different types of restorative materials used did not show the ability to guarantee significantly more acid-resistance tooth structure against demineralization.
Ladan Ranjbar Omrani, Masumeh Hasani Tabatabaei, Soma Faridi, Elham Ahmad,
Volume 30, Issue 3 (10-2017)
Abstract
Background and Aims: The aim of this study was to evaluate the effects of two fluoride containing mouth rinses on the color stability of two different resin composites.
Materials and Methods: 27 specimens (2×4×5 mm) were prepared from each of the following materials: a micro filled composite (Gradia, GC) and nanohybrid (Grandio). The specimens were polished by Soflex fine and superfine disks and then incubated in artificial saliva at 37°C for 24 h. The baseline color values (L, a, b) of each specimen were measured using an Easyshade spectrophotometer according to the CIELab color scale. The specimens were immersed in 20 mL of each mouth rinse and stored in an incubator at 37°C for 12 h. After incubation, the color values of all specimens were measured again, and the color change value (ΔE) was calculated. Data were analyzed by a 2-way analysis of variance at a significance level of 0.05.
Results: None of the mouth rinses created clinical significant color changes in the samples. There was no statistically significant difference among color susceptibility between resin composites (P=0.330). The interaction between the effect of mouth rinses and type of restorative materials was not statistically significant (P>0.05).
Conclusion: Accordance to the results of this study, the fluoride containing mouth rinses does not create color change in resin composites.
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.
Kimia Negahdari, Maryam Sadat Tavanagar, Rafaat Bagheri,
Volume 30, Issue 4 (1-2018)
Abstract
Background and Aims: Microhardness, sorption, and solubility are useful predictors of a resin composite’s clinical success. This study aimed to evaluate the effect of 60 days of water storage on the microhardness, sorption, and solubility of 3 commercial nanohybrid resin composites.
Materials and Methods: Three nanohybrid composites were evaluated: GC Kalore (GC), Aura (SDI), and G-ænial Universal Flo Universal Flo (GC). Ten disc-shaped samples were prepared for each material. After baseline weight measurement, the specimens were stored in distilled water for a period of 60 days, and then in desiccators for another 60 days. Specimens were weighed at 24 hours, 7 and 60 days of water storage and desiccation. For the microhardness test, 24 were prepared for each material and divided into 6 groups based on storage media (dry and wet) and storage time (24 hours, 7 days, and 60 days). Specimens were tested by a digital Vickers microhardness tester after storage and data were analyzed using SPSS software.
Results: G-ænial Universal Flo Universal Flo showed the highest sorption and solubility and the lowest microhardness after 60 days of water storage. GC Kalore showed lower sorption and solubility compared to Aura. Also GC Kalore had higher microhardness than Aura after 60 days of storage in water, while Aura had higher microhardness in dry storage.
Conclusion: Composites with lower sorption and solubility showed higher microhardnss in wet conditions. Flowable composite resin showed the lowest microhardness and the highest sorption and solubility values. Therefore, the negative effect of water sorption and solubility on Surface microhardness should be considered in clinical decisions.
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.
Seyyede Fateme Basri, Rafat Bagheri, Maryam Sadat Tavangar,
Volume 31, Issue 1 (6-2018)
Abstract
Background and Aims: Fracture and color change are among the most common causes of clinical failure of resin composite restorations. Therefore, this study aimed to examine the fracture toughness and color changes of 3 Nano-hybrid resin composites in dry and wet conditions.
Materials and Methods: Three resin composites were studied. A total of 36 rectangular specimens were prepared for each material, randomly divided into 2 groups, and stored at 37°C dry or soaked in distilled water. In each group, the specimens were subdivided into three groups (n=6) and stored for 1, 7, and 60 days. After each time interval, the specimens were tested for the fracture toughness and loaded at a cross-head speed of 0.5mm/min using a universal testing machine. The baseline and final color measurement was recorded for each specimen using a spectrophotometer. The collected data was analyzed using ANOVA and Kruskal-Wallis tests.
Results: After 60 days, the mean value of fracture toughness was lower in the wet condition compared to that of dry condition. However, it was not significantly different except for aura Bulkfil (P=0.001). Color change was significantly different for Tetric Evoceram and aura with a greater value in the wet condition compared to that of dry (P=0.004). The greatest color stability was found for aura and the least for Tetric Evoceram.
Conclusion: In this study, most of the materials stored in a dry condition showed a greater fracture toughness and color change.
Ramin Mosharraf, Aref Sadeghian,
Volume 31, Issue 3 (11-2018)
Abstract
Background and Aims: In endodontically treated teeth, the fiber posts are used to retain a core restoration. The purpose of this study was to evaluate the effect of different resin cements on the bond strength of fiber reinforced composite posts to root canal dentin, and comparing the bond strength in different sections of root.
Materials and Methods: In this in-vitro experimental study, 48 extracted single-canal central incisors were endodontically treated. For the push out test, the posts were divided into 3 groups according to one of the following three different cement materials (n=16) (Bifix SE, Bifix QM, Rebilda). Three slices with a thickness of 2-mm were prepared of each root. The push-out tests were performed at a cross-head speed of 1 mm/minute using a universal testing machine. Data were analyzed by two-way and one-way ANOVA test followed by Tukey post hoc test (α=0.05).
Results: There was no significant differences between the mean push out bond strength of three experimental groups (P=0.650), but there were significant differences between the mean push out bond strength of root dentin regions (P<0.001).
Conclusion: Under the conditions of this study, there was no significant difference between the mean push out bond strength of 3 different resin cement systems. The coronal region of root dentin showed significantly higher mean bond strength values than that of the middle and apical thirds.
Fatemeh Ensafi, Tabassom Hooshmand, Maryam Pirmoradian,
Volume 32, Issue 1 (7-2019)
Abstract
Background and Aims: Today, resin composites are one of the most commonly used materials in restorative dentistry. However, failure in resin treatments is also common due to its chemical nature and its high talent for decay recurrence. According to conservative approaches, "conservative" treatments are more likely to be considered than "Replacement" of damaged remedies. The purpose of this study was to compare different surface preparation methods on composite surfaces to achieve the highest bond strength between the old and new composites after accelerated aging.
Materials and Methods: First, composite cylinders with a diameter of 6 and a height of 5 mm were prepared using an incremental technique and a microhybrid resin composite. The specimens were stored in distilled water for 6 months at 37°C and then the surfaces of all aged compsites were roughened using diamond milling followed by phosphoric acid etching. The specimens were randomly subjected into five groups. Group 1: GC Composite Primer. Group 2: Universal bonding containing silane (Kuraray). Group 3: Self etching adhesive (SE bond; Kuraray) Group 4: silane (Ivoclar Vivadent) + Second bottle of SE bond bonding system (Kuraray). Group 5: control group with no treatment. Then, 5 mm incremental of new composite (similar to the aged composite with different color) were placed on the surfaces of specimens, sectioned, and thermocycled for 3000 cycles for the microtensile bond strength evaluation. The specimens were evaluated using a stereomicroscope after failure. Data were analyzed by one-way ANOVA and Post Hoc Tukey test.
Results: The specimens in which silane and SE bond were used showed the highest mean microtensile bond strength and those treated by universal bond showed the least bond strength which were significantly different (P=0.02). All samples had cohesive failure patterns in all groups and the percentage of failures in old and new composites did not differ significantly (P=0.69).
Conclusion: : Based on the results, all surface preparations used in this study could provide an appropriate bond strength for repair of old composite restorations. Also, the microtensile bond strength between the old and new composites was higher than the cohesive strength of resin composite itself. However, the mean microtensile bond strength value for the group treated by universal bond was significantly lower than those treated by silane and hydrophobic containing bonding system.
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.
Fatemeh Kazemi Bidhendi, Mahshid Mohammadi Basir, Doctor Mohammad Bagher Rezvani, Doctor Ali Khodabakhsh, Hossein Labbaf, Mohammad Amin Fahimi,
Volume 35, Issue 0 (5-2022)
Abstract
Background and Aims: Finishing and polishing of composites is a critical step influencing the clinical service of restorations. The aim of this article was to evaluate and compare the effect of two liquid polishes on the polish retention of two nanocomposites.
Materials and Methods: Eighty standardized disk-shaped specimens (4×2 mm) were prepared from two nanocomposites (n=40), including one nano-filled composite (Filtek Z350 XT-3M ESPE, USA) and one nano-hybrid composite (Aelite Aesthetic Enamel-Bisco, Inc. Schaumburg, USA). The specimens were randomly divided into 4 subgroups (n=10) based on the method of finishing (F) and polishing (P) procedures: M: as control, polymerized under Mylar strip; S: finish and polish with a sequence of Sof-Lex discs (3M ESPE, USA); SP: finish and polish with Sof-Lex discs and use of Permaseal liquid polish (Ultradent products, Inc. USA); SB: finish and polish with Sof-Lex discs and use of Biscover liquid polish (Bisco, Inc. Schaumburg, USA). The specimens were undergone pH cycling and brushing machine and then, the average surface roughness (Ra) and average profile changes along the desired area (Rz) of the specimens were determined with profilometer instrument. Two-way and one-way analysis of variance (ANOVA) was used to compare the mean of surface roughness. Then, Tukey test was used to identify the groups responsible for the difference and t-test was used to compare the mean of surface roughness.
Results: The type of composite and the method of polishing procedure had no effect on the mean Ra (P=0.733) but it had significant effect on Rz1 factor (P=0.025).
Conclusion: Using liquid polish after polishing discs had no effect on the polish retention of nanocomposites.
Neda Samie, Azita Kaviani, Soroor Samie, Ali Saramipour,
Volume 38, Issue 0 (4-2025)
Abstract
Background and Aims: Oral health affects the quality of life and plays the main role in achieving optimal conditions of health and general well-being. Therefore, this study was conducted with the aim of investigating the psychosocial effects and quality of life related to oral health in patients treated with composite veneers.
Materials and Methods: In this cross-sectional study, 48 patients who referred to the restorative department of Jundishapur University of Ahvaz for composite veneer treatment were participated. The PIDAQ questionnaire was used to investigate the aesthetic effects of composite veneer treatment on the psychosocial conditions of the patients, and the OHIP-14 questionnaire was used to investigate the quality of life related to oral health. Patients were asked to complete both questionnaires before treatment and one month after composite veneer treatment. Also, demographic information including age, sex, education and marital status of the patients were recorded. The purpose and benefits of participating in this study were fully explained to the patients and the patients voluntarily participated in this study. Then, an informed consent form was given to the patients. In order to compare the scores before and after the treatment, the paired T-test and its non-parametric equation expression (Will-Coxon) were used, and P<0.05 was considered.
Results: According to the results, the average age of the respondents was 28 years. In terms of gender, 54.2% of the patients were male, and in terms of education, most of the participants in the study had a bachelor's degree (35.4%). The total score of OHIP-14 before treatment was 26 and after treatment 22. Also, the total score of PIDAQ before treatment was 49 and after treatment 28. Comparing the scores of psychosocial effects and quality of life related to the oral health before and after composite veneer treatment showed that there was a difference between the average score of psychosocial effects and quality of life. There was a significant difference related to the oral health before and after composite veneer treatment, which significantly decreased after treatment (P<0.05).
Conclusion: The present study showed that suitable veneer composite treatments could improve the oral health related to the quality of life of people. Also, treatment with composite veneers could have a significant effect on patients' self-confidence. Composite veneers could reduce social effects, psychological effects, and cosmetic concerns related to patients’ teeth.
Abdolrahim Davari, Farnaz Farahat, Marjan Mehravaran, Alimohammad Doosthosseini, Negar Etminan,
Volume 38, Issue 0 (4-2025)
Abstract
Background and Aims: Finding an appropriate method for polishing that can be used in dental practices to improve the longevity and ease of dental restorations is of great importance. The aim of this study was to evaluate the effect of different polishing methods on the surface roughness of two types of nano-hybrid composites, an in vitro study.
Materials and Methods: In this study, 42 samples in the form of discs (6 mm in diameter and 3 mm in thickness) of two nano-hybrid composites (Charisma Kulzer and EvoCeram Tetric IPS) were prepared. Each group had 21 samples (polymerized in a mold made of polyfluorohalide material) and were all shaded (A2 color). To prevent mirror-like reflections, each sample was covered. A 2 kg load was applied for 30 seconds on each sample, after which the composites were removed. The samples were stored for 7 days in deionized water at room temperature and in the dark. After this period, the samples underwent finishing and polishing procedures. Seven random samples from each composite group were polished using different methods: System Gloss Composite LUCIDA, EVE polishing discs, and EVE polishing discs + Cosmedent polish. The surface roughness was measured using a profilometer, and observations were made under a microscope. Data were analyzed using SPSS 25 software with t-tests, ANOVA, and the Bonferroni post hoc test.
Results: The two-stage method using EVE polishing discs showed significantly the lowest surface roughness in both types of composites (P<0.0001). The type of composite did not have a significant effect on initial surface roughness (P=0.067), but the polishing method had a significant effect on the surface roughness (P<0.0001). The difference in the mean surface roughness was statistically significant among different polishing methods for either type of composites (P<0.0001). The t-test analysis showed no significant difference in the surface roughness between the two types of composites with different polishing methods (P>0.05), except in the LUCIDA polishing system where a significant difference was observed in both groups.
Conclusion: The results showed that the polishing method had a significant effect on the surface roughness and not the type of composte. The use of EVE polishing discs effectively reduced the surface roughness in both types of nano-hybrid composites used in the present study.
Sayeh Hamedanchi, Hafez Vahedpour, Solmaz Charmi,
Volume 39, Issue 0 (3-2026)
Abstract
Background and Aims: Repairing existing composite restorations, rather than replacing them entirely, is regarded as a conservative and tissue-preserving approach in restorative dentistry. However, achieving a durable bond between the aged and newly applied composite resin remains a significant clinical challenge. This study aimed to compare the shear bond strength of repaired composite restorations using three different adhesive systems.
Materials and Methods: In this in vitro study, which conducted at the Faculty of Dentistry, Urmia University of Medical Sciences, 60 disk-shaped composite specimens were fabricated with standard dimensions. After undergoing artificial aging (storage in distilled water for 6 months), their surfaces were roughened mechanically using a diamond bur. The specimens were randomly divided into three groups (n=20) and repaired using fifth-generation (Adper Single Bond), seventh-generation (OptiBond All-In-One), and universal (Single Bond Universal) adhesives, followed by the application of new composite. All specimens were subjected to thermocycling, and the shear bond strength was measured using a universal testing machine. Fracture patterns of the samples were also examined using a stereomicroscope to determine the modes of failure. Data were analyzed using one-way ANOVA and Chi-square tests in SPSS at a significance level of 0.05.
Results: The mean shear bond strengths were 15.22 ± 4.47 MPa for Adper Single Bond, 14.05 ± 4.66 MPa for OptiBond All-In-One, and 13.44 ± 4.68 MPa for Single Bond Universal. No statistically significant differences were found among the groups (P=0.468). Fracture pattern distribution was also not significantly different (P=0.453), with predominantly cohesive or mixed failures observed across all groups. No adhesive failures were observed.
Conclusion: Under standardized surface preparation, none of the tested adhesive systems demonstrated a statistically significant advantage in the shear bond strength between the aged and new composite. Therefore, the choice of adhesive in composite repair procedures can be guided by practical considerations such as product availability, ease of application, and dentist preference.
