Journal of Dental Materials and Techniques最新文献

{"title":"Corrosion of Ni-Ti Rotary Instruments: A Review","authors":"Z. Mohammadi, J. Kinoshita, A. Manabe, Mikihiro Kobayashi, S. Shalavi, H. Jafarzadeh","doi":"10.22038/JDMT.2019.14144","DOIUrl":"https://doi.org/10.22038/JDMT.2019.14144","url":null,"abstract":"The nickel-titanium (Ni-Ti) alloys used in endodontics contain 56% Ni and 44% Ti. The 2 unique features related to clinical dentistry (i.e., shape memory effect and superelasticity) are due to the transition from austenite to martensite in Ni-Ti alloy. When a superelastic Ni-Ti alloy undergoes a low tensile loading, normal elastic behavior occurs. In fact, at higher tensile loads, the elastic stress may reach a level at which there is extended horizontal region of elastic strain. The shape-memory property of Ni-Ti is derived from an atomic arrangement different from that of alloys like stainless steel. The purpose of this paper was to review the unique features of this alloy and mechanism of corrosion.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"25 1","pages":"215-219"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87893399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparing a Combination of Saline and Chlorhexidine with Saline as Root Canal Irrigation Solutions in Pulpectomy of the Primary Molars in 6-9 Years Old Children, A Double Blind Clinical Trial","authors":"Mahsa Sayadizadeh, Raziyeh Shojaeipour, Masoumeh Aminizadeh, A. Horri, Sajad Raeisi Estabragh, Mohammadjavad Aminizadeh, Farzaneh Jalali","doi":"10.22038/JDMT.2019.13898","DOIUrl":"https://doi.org/10.22038/JDMT.2019.13898","url":null,"abstract":"Introduction: Using irrigation solutions in pulpectomy procedures for children is the best technique to dissolve and remove the soft necrotic materials during instrumentation. Normal saline solution (NSS) has no antibacterial activity and only results in root canal cleaning during irrigation. The 2% chlorhexidine gluconate (CHX) solution significantly decreases bacterial colonies, compared to NSS. The present study was performed to evaluate the success of irrigation by NSS and CHX combined solution, in comparison to NSS. Materials and Methods: The current study was conducted on 60 children aged 6‒9 years allocated to the two groups of test and control. All the participants had one primary molar tooth with signs and symptoms of irreversible pulpitis. During pulpectomy of the 30 teeth, the standard technique, consisting of irrigation with 0.9% NSS was used for the control group. The 30 teeth of the remaining subjects in the case group were irrigated with an equal volume of 0.2% CHX and NSS combination. Clinical radiographic follow-ups were scheduled at 6 and 12 month post-operation intervals. Results: The success rates at 12 month follow-up from clinical and radiographic viewpoints in the control group were 83% and 73%, respectively. For the case group, success rates of 97% and 90% were reported clinically and radiographically, respectively. There were no significant diffferences between the case and control groups at 6- (P= 0.492) and 12- (P= 0.195) month clinical follow-ups.     On the other hand, the two groups were siginificantly different regarding the 6-month radiographic follow-up (P=0.038); however, such difference was not significant at the 12-month follow-up (P=0.095). Conclusion: Theone-year follow-up showed that there is no diffference between CHX and NSS as irrigation solutions for cleaning the root canals of primary teeth with irreversible pulpitis.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"17 1","pages":"174-181"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85062491","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of the Effect of an Experimental Herbal versus Fluoridated Mouthwash on Frictional Resistance and Surface Roughness between Orthodontic Brackets and Two Types of Archwire: In Vitro Study","authors":"Naser Abdelgader Alwafe, S. Hammad, Noha A El-Wassefy, A. Hafez","doi":"10.22038/JDMT.2019.14143","DOIUrl":"https://doi.org/10.22038/JDMT.2019.14143","url":null,"abstract":"Introduction: The present study aimed to evaluate an experimental herbal mouthwash, as compared to sodium fluoride mouthwash on the frictional resistance and surface roughness between brackets and two rectangular archwire types. Methods: A total of 60 premolar׳s brackets engaged with 0.019×0.025 archwires made of stainless steel and nickel-titanium alloys were used in this study. The samples were assigned into three groups, each group contained ten stainless steel archwires-brackets and ten nickel titanium archwires-brackets combination. Thereafter, these samples were immersed in herbal mouthwash, sodium fluoride mouthwash (study groups) and artificial saliva (control group) for 90 minutes. Universal testing machine was used to test the friction resistance in the three groups. Atomic force and scanning electron microscopes were used to evaluate the surface roughness of wires and bracket surface topography, respectively. Results: The samples immersed in sodium fluoride mouthwash illustrated the highest mean friction resistance and mean surface roughness, followed by herbal mouthwash and the least was for artificial saliva. Conclusion: The 90-minute immersion in herbal mouthwash did not exert any significant effect on frictional resistance or surface roughness among orthodontic brackets and archwires made of stainless steel and nickel titanium. Based on the results, herbal mouthwash may be prescribed as a non-destructive prophylactic agent on materials evaluated in the present study for the orthodontic patient.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"7 1","pages":"205-214"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78367100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bone-Borne Maxillary Expansion and Traditional Rapid Maxillary Expansion: A Systematic Review and Meta-Analysis","authors":"A. Mashreghi, Erfan Bardideh, Hooman Shafaee, M. Dadgarmoghaddam","doi":"10.22038/JDMT.2019.14114","DOIUrl":"https://doi.org/10.22038/JDMT.2019.14114","url":null,"abstract":"Introduction: The aim of this study was to perform a systematic review and meta-analysis to compare the effect of bone-borne expansion (BBE) and tooth-borne expansion (TBE) in patients with maxillary constriction. Methods: Electronic databases, including MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials, were searched up to February 2019. Eligible clinical trials and cohort studies that studied the effects of bone-borne and tooth-borne expansion appliances on patients with constricted maxilla were selected. The study selection, data extraction, and risk of bias assessment were independently performed by two authors. Then, the random-effects meta-analysis and post-hoc heterogeneity tests were performed.  Results: In the end, four studies were included in the present meta-analysis (i.e., a randomized clinical trial, two prospective controlled clinical trials, and a cohort study) that collected data from 117 patients. The mean differences between TBE and BBE were 0.38 mm and -0.28 mm for premolar and molar apices, 0.67 mm and 1.18 mm for premolar and molar crowns, 0.19 mm and 0.17 mm for alveolar bone in premolar and molar areas, and -0.61 mm and 0.02 mm for nasal and maxillary bones, respectively. Moreover, the differences between TBE and BBE for dental angulation were 3.84◦ and 1.52◦ for left and right molars, as well as 4.85◦ and 3.46◦ for left and right premolars, respectively. Conclusion: The BBE appliances do not have any advantages over tooth-borne devices with regard to the amount of skeletal or dental expansion; however, it seems to produce less tipping in posterior teeth.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"78 1","pages":"159-168"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91293643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Stress Distribution in Four Restorative Methods in Endodontically Treated Maxillary Premolar: A 3D Finite Element Analysis","authors":"A. Daneshkazemi, Mohammad Mehdi Jalili Bahabad, Rahele Mirseifinejad, M. H. A. Iranaq, Elnaz Karimian","doi":"10.22038/JDMT.2019.14045","DOIUrl":"https://doi.org/10.22038/JDMT.2019.14045","url":null,"abstract":"Introduction: the Restoration of endodontically treated teeth is critical, and the Awareness of stresses developed by oblique and vertical forces in restorative methods take a great role in treatment plans. Due to the anatomical shape and inherent form of the stress distribution premolars, could be lost by fractures. Some fractures such as vertical fracture which is probable in endodontically treated teeth, makes the teeth a candidate for extraction and other surgical procedures. According to this fact that the dental restorations should be conservative, the aim of this study was to determine stress distribution using four composite restorative methods. Methods: Endodontically treated maxillary second premolars were restored with composite resin using four methods. For restoration, the models representing standard Mesio-occlusal-distal (MOD) restoration, cusps capping with thickness of 1 and 2mm, and the use of woven fiber in occlusal part, were prepared. The effects of the different restorative approaches on stress distribution were analyzed using three-dimensional finite element stress analysis. Results: the highest stress rate was observed in MOD tooth restoration and the amount of stress in natural parts of the tooth in woven fiber was found the lowest. Conclusion: The simulation results show that in all models, oblique forces caused more stress than vertical forces. Moreover, there was a slight difference between different types of restorations regarding the magnitude of stress; however, the results obtained from this study showed that woven fiber could partly reduce stresses.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"47 1","pages":"182-189"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78405072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Role of Root Canal Preparation on Apical Geometry: A Review of the Literature","authors":"Z. Mohammadi, J. Kinoshita, A. Manabe, Mikihiro Kobayashi, S. Shalavi, F. Palazzi, H. Jafarzadeh","doi":"10.22038/JDMT.2019.14102","DOIUrl":"https://doi.org/10.22038/JDMT.2019.14102","url":null,"abstract":"The amounts of apical enlargement have been a controversial issue for a long time. The enlargement of the apical part of the canal may severely impact the endodontic prognosis. Enlargement of the apical portion to a larger size may negatively affect the ability to control the filling material during root canal obturation. In addition, an open-apex increases the risk for overfilling which has been shown to be related with decreased success rate. The retreatment of a tooth with apically enlarged canal may be even impossible. Further preparation of an apically enlarged canal may increase the risk of iatrogenic errors and also excessive apical root weakness. The present article aimed to address in vitro and clinical studies on apical enlargement, effect of coronal pre-flaring on the size of the master apical file, and clinical applications of apical enlargement.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"59 1","pages":"169-173"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90322347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a Questionnaire to Evaluate the Knowledge and Attitudes of Medical Students Regarding Radiation Protection","authors":"H. Fakhar, A. Shamshiri, Z. Momeni, Mahdi Niknami, Niloofar Kianvash","doi":"10.22038/JDMT.2019.13377","DOIUrl":"https://doi.org/10.22038/JDMT.2019.13377","url":null,"abstract":"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.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"85 1","pages":"129-134"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80457930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison between Biaxial Flexural Strength and Microstructure of Polished and Glaze-Fired Specimens of Zirconia Lithium Silicate Glass Ceramic","authors":"Alaa M. Attaallah, E. Zayed, Salma M Dabees, Youssef Y. Ashour, A. Fahmy","doi":"10.22038/JDMT.2019.13375","DOIUrl":"https://doi.org/10.22038/JDMT.2019.13375","url":null,"abstract":"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.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"44 1","pages":"114-120"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90951344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Is the Detection of Odontoma Always Comfortable? A Case Report","authors":"F. Mashhadiabbas, N. Shamloo, H. Sadeghi, S. Ahmadi","doi":"10.22038/JDMT.2019.13380","DOIUrl":"https://doi.org/10.22038/JDMT.2019.13380","url":null,"abstract":"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.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"150 1","pages":"149-152"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75935113","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficacy of Different Irrigation Systems Used to Remove Calcium Hydroxide from the Root Canal","authors":"Seda Falakaloğlu, O. Adiguzel, Meryem Kara, Merve Yeniçeri Özata","doi":"10.22038/JDMT.2019.13376","DOIUrl":"https://doi.org/10.22038/JDMT.2019.13376","url":null,"abstract":"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.","PeriodicalId":15640,"journal":{"name":"Journal of Dental Materials and Techniques","volume":"98 1","pages":"121-128"},"PeriodicalIF":0.0,"publicationDate":"2019-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84101586","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}