Showing 22 results for Kar
S Toursavadkohi, F Zameni, M Afkar,
Volume 3, Issue 3 (8-2018)
Abstract
Background and Aim: Tubular penetration of root canal sealers prevents filling material displacement and overgrowth of microorganisms in dentinal tubules. The aim of this study was to compare the tubular penetration of AH26, EasySeal, and SureSeal sealers in single-rooted teeth using scanning electron microscopy (SEM).
Materials and Methods: Fifty human single-rooted teeth were included in this experimental study. After root canal preparation, AH26 was used in group 1, EasySeal was used in group 2, and SureSeal was used in group 3 using the lateral condensation technique. Sections at 3 mm and 6 mm from the apex were prepared and subjected to SEM analysis. Analysis of variance (ANOVA), post hoc and paired t-tests were used to compare the deepest dentinal penetration of root canal sealers.
Results: The deepest tubular penetration at 3 mm from the apex was 0.85±0.19 mm in group 1, 1.32±0.21 mm in group 2, and 1.17±0.42 mm in group 3; the difference was significant (P=0.01). The deepest tubular penetration at 6 mm from the apex was 1.09±0.3 mm in group 1, 2.12±0.45 mm in group 2, and 1.88±0.43 mm in group 3; the difference was significant (P=0.0001). The mean deepest tubular penetration was lower at 3 mm from the apex compared to the penetration at 6 mm from the apex (P=0.02).
Conclusion: It seems that tubular penetration of AH26 sealer is less than that of EasySeal and SureSeal at 3-mm and 6-mm sections.
Mr Karimi, M Montazeri, M Harandi, L Aghazadeh, L Aghazadeh,
Volume 3, Issue 4 (10-2018)
Abstract
Background and aim: Antimicrobial photodynamic therapy (aPDT) has been suggested as a novel technique for decontamination of exposed implant surfaces. We aimed to evaluate the effect of aPDT on sandblasted, large-grit, acid-etched (SLA) titanium discs contaminated with Eikenella corrodens (Ec) and Aggregatibacter actinomycetemcomitans (Aa).
Materials and methods: In this in-vitro study, twenty-four sterile SLA titanium discs were contaminated with Ec (PTCC® 1391) and Aa )ATCC® 33384( and were randomly divided into the following groups: aPDT-treated group consisted of 12 discs submerged in 1 ml of toluidine blue and exposed to a low-level laser; negative control group comprised of 6 discs rinsed with physiological saline, and positive control group included 6 discs submerged in 2 ml of 0.2% chlorhexidine (CHX). After serial dilution, each sample was cultivated in an anaerobic environment (24 hours for Ec and 48 hours for Aa). Microbial reduction rate was calculated through colony-forming unit (CFU) counting according to Kruskal-Wallis test.
Results: The number of colonies for both bacterial strains in the aPDT-treated group was significantly reduced compared to the negative control group, showing the bactericidal potential of aPDT with toluidine blue (P<0.0001). The 0.2% CHX group showed a significantly smaller amount of colonies (CFU=1.089×107 for Ec and 3×107 for Aa) compared to the aPDT-treated group (CFU=3.73±1.19×109 for Ec and 52±13.6×105 for Aa; P<0.00001).
Conclusion: aPDT with toluidine blue significantly reduces Ec and Aa contamination of SLA titanium discs; however, 0.2% CHX showed the highest bactericidal potential and is still considered the gold standard in antimicrobial treatment of peri-implant diseases.
K Salem, J Vejdani, S Espidkar, S Aghaei,
Volume 3, Issue 4 (10-2018)
Abstract
Background and aim: The effect of different milk consumption patterns in infants on the formation of dental occlusion is one of the issues under discussion. Due to the lack of specific results in this regard, the purpose of this study was to determine the occlusion of deciduous teeth in breastfed and bottle-fed infants.
Materials and methods: This is a descriptive-analytical study on 316 children aged 4-5 years old. This study was based on clinical examination and filling questionnaires. The examination was done at kindergartens and in sitting position using a dental mirror and with exposure to natural light. The occlusal relationship, overjet, overbite, and crossbite were examined through direct observation in the centric occlusion. The questionnaires were completed by the mothers. The basis of this study was the responses that mothers gave in the questionnaire based on the type and duration of breastfeeding or bottle-feeding. The collected data were statistically analyzed by Chi-square test. Significance was considered at the level of P<0.05.
Results: The results of this study showed a significant relationship between nutrition with dry milk and increased overjet (P=0.048) and distal step occlusion (P=0.001). The duration of milk consumption showed no significant relationship with any of the studied variables.
Conclusion: Malocclusion was more frequently observed in bottle-fed children.
F Sarkarat, R Kahali,
Volume 3, Issue 4 (10-2018)
Abstract
Coronoid process hyperplasia is the enlargement of the coronoid processes and may lead to their impingement upon the zygomatic arch and limitation of the mouth opening. It can be unilateral or bilateral and usually affects men in the second decade of life. The etiology of the coronoid process hyperplasia is unknown. The aim of treatment is to restore the mouth opening and the only available treatment is surgery. Intraoral coronoidectomy has been suggested as the treatment of choice. Although the immediate increase in jaw mobility is gained after surgery, proper post-operative rehabilitation and physical therapy is necessary to maintain the mouth opening.
Sh Emami Meibodi, Ma Narimani, F Sarkarat, P Omidsalar,
Volume 3, Issue 4 (10-2018)
Abstract
Abstract
Background and Aim: To date, the possibility of any correlation between pathological problems associated with cervical vertebral fusion and long facial pattern has been limitedly assessed. The aim of the present study was to find the correlation between the risk of fusion in cervical vertebrae and long facial pattern in adults.
Materials and Methods: In the present cross-sectional study, 80 lateral cephalograms with proper density and contrast were selected. The vertical facial dimension was analyzed to determine normal and long face patterns and to divide the samples into control and case groups, respectively. Cervical vertebrae were observed to detect the continuance of radiopacity between cervical vertebrae, which is considered as a risk of fusion. Data were transferred to SPSS software, and Pearson's chi-squared test was used to detect the correlation between cervical vertebral fusion and the vertical facial pattern.
Results: The analysis of the data showed that the number of samples with fusion was higher in long face samples than in samples with normal vertical facial dimensions. Pearson's chi-squared test revealed a correlation between the vertical facial pattern and the risk of fusion in cervical vertebrae (P<0.001).
Conclusion: According to the results, there is a correlation between an increase in the vertical facial dimension and the prevalence of cervical vertebral fusion.
Keywords: Adult, Cephalometry, Cervical Vertebrae, Vertebral Fusion
O Moghaddas, F Sarkarat, A Zarbakhsh, Mm Hoseini, T Bitaraf,
Volume 4, Issue 4 (10-2019)
Abstract
Background and Aim: Reducing the number of pathogenic microorganisms can contribute to reducing the incidence and epidemiology of periodontal diseases. This study aimed to evaluate the clinical effects of Ardox-X active oxygen-containing toothpaste on periodontal indices in patients with at least 1 to 2 implants.
Materials and Methods: In this crossover randomized clinical trial, 30 subjects were randomly divided into two groups (n=15). Oral hygiene instructions were delivered to all subjects before the study. Scaling and root planing (SRP) were performed for all subjects. The subjects were instructed to brush with Oral-B toothpaste and toothbrush twice daily for at least two minutes. All subjects returned 10 days later, and the plaque index (PI) and gingival bleeding index (GBI) were measured. The first group received Ardox-X, and the second group received Oral-B toothpaste. Both groups presented after 7 days, and GBI and PI were measured. SRP was performed again, and the plaque was zeroed. Both groups spent the wash-out period for 10 days. Next, the indices were measured again. The Ardox-X group received Oral-B toothpaste and vice versa. After 7 days, both groups returned, and the indices were measured again. T-test was used for statistical analysis.
Results: No significant difference was observed in the PI changes between the control (0.88±0.22%) and case (0.83±0.22%) groups (P<0.6). The changes in the GBI were significantly different between the control (3.9±3.4%) and case (1.5±2%) groups (P<0.01).
Conclusion: The results of this study showed that Ardox-X toothpaste performs better than the control group (Oral-B) in terms of the GBI.
F Sarkarat, Sa Vahdati, Hr Mahaseni Aghdam, Z Nematallahi, M Farahmand,
Volume 5, Issue 2 (5-2020)
Abstract
Background and Aim: Autogenous bone grafts are considered the gold standard although they have several disadvantages, leading to a search for suitable alternative graft biomaterials. This study evaluates the histological and histomorphometric properties of regenerated bone in defects in rabbits following the application of two commercially available xenografts (Bio-Oss and Osteon).
Materials and Methods: This animal study was carried out on 14 New Zealand rabbit calvaria. Four 6.5-mm critical-size defect (CSD) models of bone regeneration were formed in each surgical site. The first defect was filled with Bio-Oss, the second with large Osteon (L-Osteon), the third with small Osteon (S-Osteon), and the last one remained unfilled (the control group). The cases were sacrificed. Bone forming properties (amount of new bone formation, inflammation, and foreign body reaction) were observed at 4- and 8-week intervals through histological and histomorphometric examinations. The Friedman test, Kruskal-Wallis test, and Wilcoxon test for multiple comparisons were used for data analysis. The level of statistical significance was set at 0.05.
Results: There was no statistically significant difference for regenerated bone among the four groups (P>0.05). The L-Osteon site showed more inflammation and foreign body reaction compared to the other groups.
Conclusion: The results of this study showed that Bio-Oss and Osteon appear to be highly biocompatible and osteoconductive and can thus successfully be used as bone substitutes in augmentation procedures.
F Sayar, B Hatami, N Akhondi, E Amini, Sh Pourkarimkhani,
Volume 5, Issue 3 (8-2020)
Abstract
Background & Aim: Oral hygiene instructions are routinely provided at schools by health mentors and dentists. Recently, oral hygiene instruction by peers has gained popularity. This study aimed to compare the effect of oral hygiene instruction by dentists and peers on the level of knowledge of twelve-year old children.
Methods and Materials: In this interventional randomized clinical trial, four schools were randomly selected. The level of oral health knowledge of students was assessed by a pretest. Oral hygiene instructions were then provided by dentists in control schools and by peer mentors in test schools. Knowledge of students about oral health was evaluated in the two groups immediately and after 1 month post instruction. The mean test scores were analyzed using SPSS version 20 and compared between the groups using two-way and repeated measures ANOVA.
Results: Oral hygiene instruction enhanced the overall knowledge of students about oral health immediately and at one month after the instruction compared with baseline in both groups (P<0.05). The overall knowledge score of students in the test group was higher than that of the control group immediately and at 1 month after the instruction (P<0.05).
Conclusions: It appears that oral hygiene instruction by peer mentors can effectively increase knowledge acquisition with regard to oral health-related topics. Thus, peer mentoring in health-related topics is recommended as a practical and cost-effective approach. Considering the different pattern of learning in boys, repetition and reinforcement of instruction can promote their knowledge level in long-term.
N Sahaf, M Ghasemi, N Askarizadeh,
Volume 6, Issue 1 (3-2021)
Abstract
Background and Aim: Hearing impairment is a leading challenge in the education of deaf children. Compared to normal children, hearing-impaired (HI) children have poor oral health due to a lack of communication skills and effective health educations. This leads us to search for a proper method to educate these children. The present study aimed to assess the effect of different educational methods on the oral health of 7-13-year-old HI children in Tehran.
Material and Methods: In this clinical trial, 76 HI children, aged 7 to 13 years, were selected from elementary schools of deaf children in Tehran according to the entry criteria. They were examined, and the baseline plaque and gingival scores were recorded using the Silness and Loe plaque index (PI) and the Loe and Silness gingival index (GI). The children were randomly divided into two groups; one group was educated using a dental model, and the other group watched a guided training video. Oral health education was reinforced two weeks later. Reexamination was carried out 4 months later. Data were statistically analyzed using t-test with SPSS version 20.0.
Results: There was a significant reduction in plaque and gingival scores in both groups after health education (P<0.05). The highest reduction in plaque and gingival scores was seen in the dental model group.
Conclusion: In a comparison between the two educational methods (dental model and video), training using a dental model is more efficacious in improving the oral health of HI children. Continuous school-based oral health education programs for HI children need to be considered.
P Kar, R Varghese, N Agrawal, H Jhaveri,
Volume 6, Issue 3 (6-2021)
Abstract
Post-endodontic treatment pain is a major problem in dentistry. Around 80% of patients who present with preoperative pain due to endodontic treatment continue to experience the pain of some level following endodontic therapy. This pain, mostly linked to chronic inflammation, is due to bacterial toxins that signal the ingress of immune cells followed by the activation of various cytokines and inflammatory mediators. Countless classes of drugs have been studied to resolve this challenge. Glucocorticoids have been in use for more than fifty years owing to their potent anti-inflammatory effects. This paper aims to review the pharmacology and mechanism of actions of steroids as an intracanal medicament considering the indications, contraindications, and side effects.
F Sarkarat, Ar Tootoonchian, Sh Mirpour, M Moogahi Nezhad, Sh Haeri Araghi, V Rakhshan,
Volume 7, Issue 3 (7-2022)
Abstract
Background and Aim: Coronavirus disease-2019 (COVID-19) is a serious pandemic situation. Assessment of associated factors contributing to its severity is of clinical significance. This study assessed the factors associated with COVID-19 and its severity.
Materials and Methods: In this case-control study, we assessed self-reports of 93 COVID-19 patients and 50 healthy controls regarding demographics, smoking habit, sinusitis, rhinoplasty or tonsillectomy history, xerostomia, dysosmia, dysgeusia, taste disturbances (metallic taste and foul taste), and bleeding or inflammation in the oral cavity. Further admission to ICU or death were recorded later. We also assessed the patients’ laboratory tests including WBC, neutrophils, lymphocytes, basophils, eosinophils, C reactive protein (CRP), and erythrocyte sedimentation rate (ESR) at the time of admission. Diagnosis of patients was based on clinical assessments, Reverse transcriptase polymerase chain reaction (RT-PCR) and chest computed tomography (CT) scan results. Healthy controls had no flu like signs and symptoms in the past 1 month prior to the study. Associations between the abovementioned factors and disease, and disease severity were analyzed by the Chi-square test, independent-sample t-test, one-sample t-test, and Spearman’s correlation coefficient (α=0.05).
Results: Variables with statistically significant associations with COVID-19 included smoking (P=0.004), xerostomia (P=0.000),
dysgeusia (P=0.000), dysosmia (P=0.000), and taste disturbances (P=0.000). CRP (P=0.000), ESR (P=0.000), and neutrophil percentage (P=0.000) were also elevated in patients. Eosinophil (P=0.000) and basophil percentages (P=0.016) were lower than normal range in patients. Age was associated with death (P=0.010) and ICU admission (P=0.009).
Conclusion: Xerostomia, dysgeusia, dysosmia, and taste disturbances can be early markers of COVID-19. Older ages are prone to more severe forms of disease. |
H Heshmat, M Hoorizad Ganjkar, N Sanaei, Sf Tabatabaei, Mj Kharazifard,
Volume 7, Issue 3 (7-2022)
Abstract
Background and Aim: This study aimed to compare the sorption and solubility properties of ACTIVA BioACTIVE liner and resin modified glass ionomer (RMGI).
Materials and Methods: In this in vitro study, a total of 30 samples were fabricated from each liner measuring 15 mm in diameter and 1 mm in thickness according to ISO 2009:4049. They were then divided into 6 subgroups (n=5) to assess their water solubility after 1 week and 8 weeks, water sorption after 1 week and 8 weeks, and acid solubility after 1 week and 8 weeks. The samples were then weighed, and placed in vials containing artificial saliva or lactic acid and incubated at 37°C for 1 week or 8 weeks according to specimen grouping. Afterwards, each specimen was weighed again. Sorption and solubility were calculated according to difference in weight of the samples. Data were analyzed by two-way ANOVA(alpha=0.05).
Results: RMGI showed greater water solubility and sorption compared with ACTIVA BioACTIVE liner after 1 week of storage (P=0.00). No significant difference was found in water solubility (P=0.64) and sorption (P=0.15) after 8 weeks of storage. There was no significant difference in acid solubility of RMGI and ACTIVA BioACTIVE liner after 1 week (P=0.30) or 8 weeks of storage (P=0.60)
Conclusion: Water sorption and solubility of RMGI were greater than those of ACTIVA BioACTIVE within the first week after setting but they were similar in long-term assessment. RMGI and ACTIVA BioACTIVE were not different in terms of acid resistance. |
M Rafiei, E Moradi Askari, M Sadeghi, M Mollahasani Kahdouyi, N Zeini,
Volume 7, Issue 4 (10-2022)
Abstract
Background and Aim: The present study aimed to evaluate the materials, methods, and equipment used by general dentists in southeastern Iran for endodontic treatments in 2021.
Materials and Methods: In this cross-sectional study, 121 standard questionnaires were distributed among general dentists in Rafsanjan city, Iran. The questionnaire included demographics and questions regarding the type of materials, methods, and equipment selected by general dentists. The collected data were analyzed by SPSS version 22 using the Chi-square test and ANOVA.
Results: The response rate of the participants was 83%(n=100); of which, 55% were females and 45% were males. Only 28% of dentists performed pulp vitality tests, and 46% performed sinus tract tracing in case of infection. Cotton rolls were used by 71% for further isolation, apex locator and radiography were used concurrently to determine the working length by 62%, and canal preparation was done by rotary and manual files by 48%. Rotary M3 and ProTaper files were more commonly used by dentists. Electric rotary handpieces were used for canal instrumentation by 64%, and rotary orifice shapers were more commonly used for canal flaring (61%). The most commonly used obturation method was lateral compaction. Most general dentists used formocresol-impregnated cotton pellets for pulpotomy (43%). Half of the dentists used saline for canal irrigation. Calcium hydroxide was the most commonly used intracanal medicament (87%), and 53% used polymerized sealers.
Conclusion: General dentists evaluated in this study violated some of the standards and need to take more training courses. |
Elnaz Tavazo Zadeh, Parissa Aref, Nahid Askarizadeh, Fatemeh Emadi,
Volume 8, Issue 1 (1-2023)
Abstract
Background and Aim: Considering the search for an effective antimicrobial agent comparable to chlorhexidine (CHX), this study aimed to assess the antimicrobial effect of Punica granatum (P. granatum) hydroalcoholic extract on Streptococcus sobrinus (S. sobrinus), Streptococcus sanguinis (S. sanguinis) and Candida albicans (C. albicans), in comparison with CHX.
Materials and Methods: In this in vitro study, the disc diffusion test was used to assess the antimicrobial activity of the extract by measuring the growth inhibition zones; while, the microdilution and macrodilution broth tests were applied to find the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract against the tested microorganisms. The MBC was measured using the blood agar or Mueller Hinton agar culture medium. The Sabouraud dextrose agar culture medium was used for C. albicans. Each test was repeated in triplicate, and data were analyzed by independent samples t-test and Mann-Whitney U test.
Results: None of the tested microorganisms showed any resistance to the extract. CHX had the highest antimicrobial effect against all tested microorganisms. The MIC of the hydroalcoholic extract of P. granatum was 2.5 mg/mL for S. sobrinus and S. sanguinis, and 5 mg/mL for C. albicans. Its MBC was 5 mg/mL for S. sobrinus and S. sanguinis, and 10 mg/mL for C. albicans. The mean diameter of the growth inhibition zone for S. sobrinus caused by CHX was significantly greater than that caused by P. granatum extract (Mann-Whitney U test, P=0.043). The same result was obtained for S. sanguinis (Student sample t-test, P=0.002), and C. albicans (Mann-Whitney U test, P=0.046).
Conclusion: The hydroalcoholic extract of P. granatum has bacteriostatic and bactericidal effects on S. sanguinis and S. sobrinus and antifungal effect on C. albicans comparable to CHX.
Marjan Soleimani, Nayyereh Amini, Nahid Askarizadeh,
Volume 8, Issue 2 (4-2023)
Abstract
Background and Aim: Considering the importance of oral health in children, it is important to find factors affecting it. Eating habits, body mass index (BMI), and educational level and socioeconomic status of the parents have been suggested as factors affecting oral health. Two important indices for evaluation of general and oral health of children are the BMI and DMFT/dmft, respectively. The purpose of this study was to assess the relationship between these two indices in children aged 6-12 years.
Materials and Methods: In this descriptive analytical study, 300 children aged 6-12 years were selected among those referred to the Dental Branch of Tehran Islamic Azad University of Medical Science in 2019-2020 by simple random sampling. The BMI and dmft/DMFT were calculated, and the relationship between them and the effect of influential factors on dental caries score were evaluated. Data were analyzed by the linear regression model at a confidence interval of 95% and 0.05 level of statistical significance.
Results: The study sample consisted of 168 girls and 132 boys. The mean dmft was 4.66±3.39 and the mean DMFT was 1.44±1.57 Only 11.34% of the children were underweight and 12.66% were obese; while, 60.67% had a normal weight. Oral health and nutritional behaviors of children showed that 71.3% of them brushed their teeth at least once a day and only 22% used dental floss. A correlation was found between BMI and the rate of caries in permanent teeth (P=0.046). |
Conclusion: No statistically significant association was observed between dmft/DMFT and BMI of children aged 6-12 years.
Arezu Babasafari, Ezatollah Jalalian, Arash Zarbakhsh, Abdolkarim Rostamian, Shaghayegh Golalipour, Sotoudeh Khorshidi,
Volume 8, Issue 3 (8-2023)
Abstract
Background and Aim: This study aimed to assess the effect of horizontal cantilever on microgap and microleakage at the implant-straight abutment interface in cement-retained crowns.
Materials and Methods: In this experimental study, 12 implant-abutment assemblies and 12 cement-retained crowns were evaluated. The implant fixtures were bone-level, and had 10 mm length and 4 mm diameter. Straight titanium abutments had 7 mm length, 4 mm diameter, and 1 mm gingival height with Morse-Taper connection. Two groups were evaluated: 6 cement-retained crowns with a horizontal cantilever (test group) and 6 cement-retained crows without a horizontal cantilever (case group). The assemblies underwent load cycling in a chewing simulator. Cyclic load (75 N) with 1 Hz frequency was applied along the longitudinal axis of each specimen to the triangular ridge between the mesiobuccal and mesiolingual cusps of the crown. The amount of microgap before and after cyclic loading, and the microleakage score after immersion in fuchsine were evaluated under a light microscope. Data were compared by t-test (alpha=0.05).
Results: The change in microgap after cyclic loading compared with before was not significant in the control group (P=0.724). However, in the case group, the amount of microgap significantly increased after cyclic loading compared with before (P=0.000). Microleakage in the case group was significantly greater than that in the control group (P=0.019).
Conclusion: Horizontal cantilever caused horizontal microgap and increased the microleakage at the implant-straight abutment interface. |
Lakshmi Rathan A. C., Shreeya Varma, Vivek Narayanan, Saravanan Chandran, Kartik Ramakrishnan,
Volume 8, Issue 3 (8-2023)
Abstract
Background and Aim: Dental surgeons are responsible for each and every step taken for dental treatment of patients. The aim of this study was to assess the knowledge, experience, and perception of dental students and practitioners regarding dento-legal aspects of dentistry.
Materials and Methods: A total of 200 students and dental practitioners were selected from the Chennai colleges. A well-structured validated questionnaire comprising of 21 questions related to dento-legal aspects of dentistry was used for data collection to assess the knowledge, experience, and perception of participants regarding dento-legal aspects of dentistry, which included clinical scenario-based questions. The responses were tabulated and analyzed using OpenEpi software. All variables were analyzed descriptively.
Results: Out of 200 participants surveyed, 53.6% were dental practitioners and 46.4% were dental students. Of all, 75% of dental practitioners and students were well aware of the dento-legal issues. Also, 50% of undergraduates and 65% of postgraduates were aware of their rights to protect themselves in legal cases. More than 50% of dental practitioners and students were aware of how to manage mishaps in a dental clinic. Out of 200 participants, 70% of dental practitioners and students were aware of the rules and regulations, and liabilities related to their practice.
Conclusion: Considering the present results, more emphasis should be placed on raising awareness among undergraduates regarding dento-legal aspects of dentistry and prevention of mishaps due to negligence during treatments. |
Negar Madihi, Maryam Hoorizad Ganjkar, Negin Nasoohi, Ali Kaboudanian Ardestani,
Volume 8, Issue 4 (11-2023)
Abstract
Background and Aim: The use of traditional camphorquinone (CQ) photo-initiators in dental composites may cause undesirable yellow discoloration. An alternative photo-initiator called lucirin trimethylbenzoyl-diphenyl-phosphine oxide (TPO) was recently introduced which exhibits minimal color change (ΔE). This study evaluated the color change of TPO-containing composites cured by different types of light-curing units, after accelerated artificial aging (AAA).
Materials and Methods: In this in vitro experimental study, specimens were fabricated from Tetric N-Ceram and Vit-l-escence TPO-containing composites with 10 mm diameter and 2 mm thickness (n=10) and light-cured by Bluephase G2 polywave and Bluephase C5 monowave curing units. The samples were polished with Sof-Lex discs and underwent initial colorimetry by a spectrophotometer after 24 hours. Aging was performed for 384 hours in a weathering chamber and final colorimetry was then performed. The results were analyzed by two-way ANOVA.
Results: The interaction effect of light curing unit and composite type on ΔE was not significant (P=0.53). The mean ΔE of Vit-l-escence and Tetric N-Ceram cured with Bluephase G2 and Bluephase C5 light-curing units was 1.67±0.48 and 1.62±0.45, and 2.59±0.29 and 2.69±0.26, respectively. Tetric N-Ceram demonstrated significantly greater ΔE than Vit-l-escence (P=0.001). Light curing units had no significant difference in ΔE (P=0.80).
Conclusion: The ΔE of TPO-containing composites does not depend on the type of light curing unit but depends on the type of composite. Aging caused discoloration of the composites but this discoloration was clinically acceptable (ΔE<3. 3). |
Gholamreza Esfahanizadeh, Reza Kooshki, Hamed Karimipoor, Verishe Rastin,
Volume 9, Issue 1 (3-2024)
Abstract
Background and Aim: This study aimed to assess the effects of chlorhexidine (CHX) and Listerine mouthwashes on color stability of glazed bilayer zirconia and IPs e.max ceramics.
Materials and Methods: This in vitro experimental study was conducted on 36 glazed bilayer zirconia and IPS e.max ceramic specimens. The baseline CIE L*a*b* color parameters of specimens were measured by a spectrophotometer. The bilayer zirconia and IPS e.max ceramic specimens were then randomly assigned to two subgroups for immersion in 10 mL of 0.2% CHX (n=9) and 10 mL of Listerine (n=9). The specimens were immersed in the respective solutions for 2 minutes daily for 7 days. Next, their color parameters were spectrophotometrically measured again. The color change (∆E) of ceramics in the three groups was calculated and compared by the Kruskal-Wallis test and two-way ANOVA (alpha=0.05).
Results: The L*, a*, and b* color parameters of glazed bilayer zirconia and IPs e.max ceramic specimens were not significantly different at baseline (P=0.8) or after the intervention (P=0.6). The ∆E of the subgroups was not significantly different either (P>0.05).
Conclusion: Both glazed bilayer zirconia and IPs e.max ceramics showed clinically acceptable color stability (∆E<3.3) following immersion in CHX and Listerine mouthwashes.
Maryam Hejazi, Fateme Eskandari, Iman Saheb Karam, Bahar Asheghi,
Volume 9, Issue 1 (3-2024)
Abstract
Background and Aim: Dental healthcare professionals may encounter various infectious diseases which necessitate the application of isolation precautions. This study aimed to assess the effects of isolation precaution training on the mean scores of knowledge, attitude, and practice of Iranian dental students.
Materials and Methods: This questionnaire-based study was carried out on 80 participants including 40 undergraduate and 40 postgraduate dental students of Shiraz University of Medical Sciences, Shiraz, Iran. A self-administered questionnaire including three scales of knowledge, attitude, and practice was used for data collection. A pamphlet was also distributed among the participants regarding infection control isolation precautions. After 4 weeks, the participants were asked to fill out the same questionnaire again. Paired t-test and Pearson’s correlation test were used to statistically analyze the data (alpha=0.05).
Results: The mean knowledge score was significantly higher in postgraduate than undergraduate dental students (P=0.030). The mean knowledge scores of postgraduate (P=0.032) and undergraduate (P=0.001) dental students significantly improved after the intervention. The intervention also significantly increased the mean attitude score of postgraduate dental students (P=0.016). A positive linear correlation was detected between practice and attitude (r=0.244, P<0.05).
Conclusion: The mean knowledge and attitude scores of postgraduate and undergraduate dental students in the present study were higher than those of previous studies. However, the mean practice score was poor. Moreover, isolation precaution training increased the mean scores of knowledge and attitude. More equipment and continuous educational programs in accordance with the guidelines are needed.
