2024-03-28T23:15:35Z
https://jdmt.mums.ac.ir/?_action=export&rf=summon&issue=1609
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Effect of Two Disinfecting Agents on the Microleakage of Resin-Based Composite Restorations in Primary Teeth
Zahra
Bahrololoomi
Sahar
Salajeghe
Setare
Shahini Tiran
Introduction: Disinfection of the cavity preparation after caries excavation can lead to the elimination of bacterial remnants that can be responsible for recurrent caries, postoperative sensitivity, and failure of the restoration. The purpose of this study was to evaluate the effects of two disinfectants on microleakage of composite restorations in primary teeth. Methods:In this experimental study, 40 extracted primary canine teeth without caries were randomly divided into four groups of 10 teeth, namely control group (1), pretreatment group with chlorhexidine 2% (2), pretreatment group with sodium hypochlorite 2/5% (3), and pretreatment group with sodium hypochlorite 5% (4). In addition, class V cavities were prepared on all teeth. The cavities were then restored with composite. The teeth were thermocycled and immersed in 2% methylene blue for 24h. Microleakage was assessed by dye penetration in the incisal and gingival surface of the teeth using stereomicroscope. Data were analyzed in SPSS software (version 18) through Kruskal-Wallis and Mann-Whitney U tests. Results: According to the results, the difference among groups was significant (P<0/001). The pair-wise comparison showed significant differences between groups 1 and 2; however, no difference was observed between pretreatment groups with sodium hypochlorite 5% and 2/5%. Furthermore, no statistically significant difference was found in terms of incisal and gingival surfaces. Conclusion:Pretreatment with chlorhexidine and sodium hypochlorite increased microleakage in composite restorations in primary teeth.
Chlorhexidine
composite restorations
Disinfectant agent
Microleakage
primary teeth
Sodium Hypochlorite
1999
11
30
107
113
https://jdmt.mums.ac.ir/article_13374_b359e2050dfb6fdfe75b91932cff0cf9.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Comparison between Biaxial Flexural Strength and Microstructure of Polished and Glaze-Fired Specimens of Zirconia Lithium Silicate Glass Ceramic
Alaa M.
Attaallah
Eman M
Zayed
Salma M
Dabees
Youssef Y
Ashour
Amal Ezz-Eldin
fahmy
Introduction: There has been a growing interest in glass ceramic systems with good esthetics, high fracture resistance, bonding durability, and simplified fabrication techniques using CAD/CAM. The aim of this study was to compare flexural strength in "polished" and "glazed and fired" specimens of zirconium lithium silicate (ZLS) CAD/CAM blocks Celtra Duo. Methods: A total of 14 specimens of Celtra Duo (Dentsply Sirona, Germany) were designated and equally divided into two groups, including group I (n=7; as polished) and group II (n=7; as glazed and fired) according to the manufacturers’ instructions. Then biaxial flexural strength was tested according to ISO 6872 using a universal testing machine and piston-on-three-ball method after polishing, glazing, and firing. The fractured surfaces and microstructure were observed by scanning electron microscope (Jeol/GSM5300). Data were then statistically analyzed using SPSS software (version 20.0). Results: There were statistically significant differences in biaxial flexural strength between a polished and glaze-fired specimen of ZLS glass ceramic discs as biaxial flexural strength was lower in polished specimens (mean±standard deviation: 158.7±21.67 MPa), while the glazed specimens showed higher biaxial flexural strength (mean±standard deviation: 261.5±31.89 MPa). Conclusion: Glazing and firing of Celtra Duo specimens increased biaxial flexural strength significantly in comparison to polishing with no significant change in the microstructure.
Celtra Duo
Piston-on-three-ball
CAD/CAM
ZLS
2019
09
01
114
120
https://jdmt.mums.ac.ir/article_13375_c8fbf9b1c7cf3c9494a638f668c83bd2.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Efficacy of Different Irrigation Systems Used to Remove Calcium Hydroxide from the Root Canal
Seda
Falakaloğlu
Özkan
Adıgüzel
Meryem
Kara
Merve
Yeniçeri Özata
Introduction: The present study aimed to compare the cleaning efficacy of passive ultrasonic irrigation (PUI), self-adjusting file (SAF), EndoVac, and conventional syringe irrigation (CSI) techniques on Ca(OH)2 removal from the root canal. Methods: This study was conducted on the mesial roots of 36 human mandibular molar teeth. After 1 month, the Ca(OH)2 was removed from the experimental groups using four different irrigation techniques (SAF, PUI, EndoVac, and CSI). The inner surfaces of the canals were examined using a stereomicroscope at 30x magnification. The assessment of remaining Ca(OH)2 medicament in the grooves was performed by three calibrated dentists using a scoring system ranged 0-3. Results: None of the groups showed complete Ca(OH)2 removal from the root canals. The PUI technique removed significantly more Ca(OH)2 from all root canals, compared to EndoVac and CSI techniques (P<0.05). In the apical third, SAF group results were significantly better than the CSI group results (P<0.05). In the middle third, the SAF technique led to significantly better results in the removal of Ca(OH)2, compared to the techniques used in other groups (P<0.05).Conclusion: Currently, there is no irrigation system that can completely remove Ca(OH)2 from the root canal in endodontics. Regarding the removal of Ca(OH)2 from root canals, the PUI technique was significantly better than EndoVac and CSI techniques. In addition, the SAF technique showed significant efficacy in the middle third of the root canals.
Passive ultrasonic irrigation
self-adjusting file
EndoVac
conventional syringe irrigation
2019
09
01
121
128
https://jdmt.mums.ac.ir/article_13376_80d1a8f948ed0c572796c14d8aa9947e.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Development of a Questionnaire to Evaluate the Knowledge and Attitudes of Medical Students Regarding Radiation Protection
Hoorieh
Bashizadeh Fakhar
Ahmadreza
Shamshiri
Zahra
Momeni
Mahdi
Niknami
Niloofar
Kianvash
Introduction: The aim of this study was to design a standard questionnaire facilitating the evaluation of the knowledge and attitude of medical students regarding radiation protection. Methods: At first, a 30-item questionnaire was prepared. The scale construction procedure was performed using content validity assessment. Considering objectives, some items were designed based on textbooks and the ideas of oral radiologists, medical physicists, and occupational medicine specialists as the expert panel. Content validity of the draft was determined by the panel. Results: Test-retest procedure was used to determine the reliability of the questionnaire by kappa statistic and Cronbach’s alpha coefficient. Experts evaluated the content validity as desirable. Kappa coefficient was more than 0.75 for almost all knowledge and attitude items. Cronbach’s alpha coefficients for basic knowledge, practical knowledge, and attitude domains were 0.793, 0.823, and 0.822, respectively. Conclusion: The designed questionnaire was confirmed as reliable considering Iranian cultural concepts.
Questionnaire
Radiation Protection
Knowledge
Attitude
medical students
2019
09
01
129
134
https://jdmt.mums.ac.ir/article_13377_c4145f8ee0e9470e211ce8fd8426eef0.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Comparison of the Cytotoxic Effects of Nanoparticulate and Microparticulate Calcium Sodium Phosphosilicate Mouthwashes on Human Gingival Fibroblasts: an in-vitro Study
Shabnam
Aghayan
Roya
Assadi
Abdolmajid
Bayandori Moghaddam
Ehsan
Seyedjafari
Introduction: This study sought to assess the cytotoxic effects of nanoparticulate and microparticulate calcium sodium phosphosilicate mouthwashes on human gingival fibroblasts (HGFs). Methods: This in vitro study was conducted on HGFs isolated and cultured in a 48-well plate containing standard culture medium for evaluation of four concentrations of the two mouthwashes at two time points plus a positive and a negative control group. The HGFs were exposed to 0.001, 0.01, 0.1 and 1 mg/mL concentrations of mouthwashes for 1 and 24 hours. Positive and negative control cells were exposed to saline and distilled water, respectively. Cell viability was assessed using the methyl thiazolyl tetrazolium (MTT) assay, and the number of viable cells was counted in triplicate using a cell counter after transfection (trypsin-EDTA 0.25%, 20 minutes) and exposure to trypan blue. The optical density (OD) values were read by ELISA reader and analyzed using the Kruskal-Wallis test. Results: Number of viable cells was not significantly different between the two mouthwashes at the two time points (P>0.05). At one hour, number of viable cells was higher in the nanoparticulate group while the number of viable cells in the microparticulate group was higher at 24 hours. Conclusion: Nanoparticulate and microparticulate calcium sodium phosphosilicate mouthwashes have no cytotoxicity against HGFs. Cytotoxicity of the nanoparticulate mouthwash was less than that of the microparticulate mouthwash. Also, increased proliferation of fibroblasts was noted over time in both groups of mouthwashes.
Cytotoxicity
Human Gingival Fibroblasts
Mouthwash
Calcium Sodium Phosphosilicate
Nanoparticles
2019
09
01
135
142
https://jdmt.mums.ac.ir/article_13378_4ebc3762355b19e072d2e5cccc6041d1.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Evaluation of Mechanical Properties of Polyethylene Glycol/ Dextrane Methacrylate / Maleic Acid Copolymer as a Biological Scaffold
Noha
Safari
Vahid
Esfahanian
Majid
Kolahdoozan
Armin
Khosravi
Abstract
Introduction: The use of membranes and transplant materials as scaffolds in periodontal regenerative surgeries is gaining an increasing application for restoring the structure and function of lost tissues. The present study aimed to evaluate the mechanical properties of PEG/MA (Polyethylene glycol/Maleic Acid) copolymer as a bioscaffold. Methods: In this experimental laboratory study, a hydrogel scaffold was first manufactured of PEG/MA copolymer. Different hydrogel concentrations were prepared using visible light through changing concentrations of C2/1, c1/1 and C1/2 (C ⅟2, C ⅟1 and C2/1) of PEG/MA copolymer to those of dex-METH (dextran-methacrylate). Then, 57 samples were selected, 27 and 30 of which were related to degradation rate and solidification tests, respectively. The samples were examined in three triplet groups within three time periods to test the degradation rate. Five quintuplet groups were also classified to measure the tensile and compressive strengths using a microtensile device. Data were analyzed by one-way/two-way ANOVA and Tukey test. Results: Both the concentration of PEG/MA copolymer (P<0.007) and sample incubation duration (P<0.001) affected sample degradation rates, with C 2/1 group yielding the lowest degradation rate. Furthermore, mean values of tensile strength (P <0.04) and compressive strength (P< 0.001) were significantly different among the three groups. Conclusion: A change in the proportion of the copolymer ingredients can affect the mechanical properties and destruction rate of the substance. Due to slow degradation rate and high tensile strength, a concentration of 1/2 is more appropriate to be used as a membrane for covering bone loss.
Maleic acid
polyethylene glycol
Dextran methacrylate
Mechanical properties
Biodegradability
2019
09
01
143
148
https://jdmt.mums.ac.ir/article_13379_c708b68df52574dfd767ebe3bbf77874.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Is the Detection of Odontoma Always Comfortable? A Case Report
Fatemeh
Mashhadiabbas
Nafise
Shamloo
Hasan
Mirmohamad Sadeghi
Samane
Ahmadi
Abstract Odontomas are the most common type of odontogenic tumors, which are often discovered by routine radiographic images or after taking films to determine the main cause of the tooth failure eruption or malocclusion. The present study aimed to describe a case of misdiagnosis and similarity of foreign body density in the radiographic appearance to odontoma in a 13-year-old male.
odontoma
Foreign body
Radiographic Appearance
2019
09
01
149
152
https://jdmt.mums.ac.ir/article_13380_0cd200934b05e84b28eb4e0a4d1ae843.pdf
Journal of Dental Materials and Techniques
JDMT
2322-4150
2322-4150
2019
8
3
Infantile Mandibular Fracture Treatment with Double-crossed Skeletal and Circummandibular Wires: A Case Report
Alireza
Khoshsirat
Sahand
Samieirad
Maryam
Hashemipour
Elahe
Tohidi
Vajiheh
Mianbandi
Abstract The prevalence of mandibular fracture is relatively lower in the pediatric population compared to adults. The treatment of these fractures is more challenging for oral and maxillofacial surgeons due to the concerns regarding mandible growth and the presence of developing tooth buds. According to the literature, conventional methods (e.g., soft diets or closed reduction) are more effective in the treatment of nondisplaced pediatric mandibular fractures. There are few case reports regarding the treatment of mandibular fractures in infants, which have mainly introduced new technique using double-crossed direct skeletal wires to reinforce circummandibular wirings for the conservative treatment of infantile mandibular fractures. The present study aimed to describe the case of a 12-month male infant with significant dislocated right mandibular parasymphysis fracture. Initially, two circummandibular wires were passed bilaterally to pull the mandibular segments for their vertical alignment. Afterwards, the skeletal buccal and lingual direct wires reinforced the previous circummandibular wiring to fit the fracture segments. Finally, all the wires were tightened simultaneously to maintain satisfactory bone reduction. Furthermore, the addition of skeletal buccal and lingual direct wires could reinforce the previous circummandibular wiring to fit the fracture segments anteroposteriorly. The fracture healed uneventfully with no complications, and intermaxillary fixation was not required in the patient. Moreover, the alveolar segments were in an appropriate position, and the maximum mouth opening of the patient was normal with no deviation, indicating a successful clinical outcome. This method was relatively reliable, noninvasive, and inexpensive, associated with the decreased discomfort and morbidity associated with maxillomandibular fixation, open reduction, and internal fixation in infants.
mandibular fracture
Closed reduction
Infant
Circummandibular wiring
2019
09
01
153
158
https://jdmt.mums.ac.ir/article_13381_634e065c6dc17cfd6586bb7470599cbe.pdf