0000000000225975
AUTHOR
Saeed Rahimi
The Discoloration effect of White Mineral Trioxide Aggregate (WMTA), Calcium Enriched Mixture (CEM), and Portland Cement (PC) on Human Teeth
Background The aim of this study was to evaluate the discoloration induced by CEM cement, Portland cement (PC) and MTA mixed with propylene glycol (MTA-PG) in comparison to White MTA. Material and methods Ninety extracted premolar and canine teeth were resected 2 mm below the CEJ. The coronal part of crown was prepared with peeso reamer and Gates-Glidden drills, and the specimens were randomly divided into 4 experimental (n=20) and one control (n=10) groups. The tooth crowns in experimental groups 1 to 4 were filled with White MTA, PC, CEM cement and MTA-PG, respectively; and in group 5, the teeth were kept empty. After incubation, digital photographs of teeth were acquired at 4 time points…
Effect of calcium hydroxide dressing on microleakage of composite restorations in endodontically treated teeth subsequent to bleaching
Objective: This study evaluates the effect of calcium hydroxide dressing on microleakage of composite restorations following non-vital bleaching. Methods: A total of 45 sound extracted human maxillary central incisors underwent endodontic treatment. The teeth were randomly divided into three groups (n=15). In group 1, access cavities were restored with composite. In group 2, the teeth underwent a bleaching procedure for one week before being restored with composite. In group 3, following a bleaching procedure, calcium hydroxide paste was placed in the pulp chamber for one week. The teeth were then restored with composite. The specimens were subjected to a dye leakage test. The data was anal…
Comparison of two histopathologic methods for evaluating subcutaneous reaction to mineral trioxide aggregate
Objectives: One of the most important factors for suitable materials for pulp therapy is biocompatibility. Two histopathologic methods of Cox and Federation Dentaire International (FDI) were used to evaluate inflammation. In Cox method, density of inflammatory cells, tissue reactions like fibrosis, vascular responses like congestion and fibrin extravasation have been used to evaluate inflammatory reactions. The aim of this study was to compare the accuracy of pathologists’ interpretations using two different methods. Study design: Three pathologists observed the degree of inflammation in 225 histopathologic sections. These sections showed inflammation in subcutaneous connective tissue of ra…
Electrochemical corrosion assessment of RaCe and Mtwo rotary nickle-titanium instruments after clinical use and sterilization
Aim: The aim of the present study was to electrochemically evaluate corrosion resistance of RaCe and Mtwo files after repeated sterilization and preparation procedures. Study Design: A total of 450 rotary files were used. In the working groups, 72 files from each file type were distributed into 4 groups. RaCe and Mtwo files were used to prepare one root canal of the mesial root of extracted human mandibular first molars. The procedure was repeated to prepare 2 to 8 canals. The following irrigation solutions were used: group 1, RaCe files with 2.5% NaOCl; group 2, RaCe files with normal saline; group 3, Mtwo files with 2.5% NaOCl; and group 4, Mtwo files with normal saline in the manner desc…
Osseous reaction to implantation of two endodontic cements : mineral trioxide aggregate (MTA) and calcium enriched mixture (CEM)
Aim: The aim of the present in vivo study was to determine bone tissue reaction to calcium enriched mixture (CEM) and mineral trioxide aggregate (MTA) using a rat femur model. Study Design: Sixty-three rats were selected and randomly divided into three groups of 21 each [experimental groups (n=15), control (n=6)]. Implantation cavities were prepared in each femoral bone and randomly filled with the biomaterials only in the experimental groups. The animals in three groups were sacrificed 1, 4, and 8 weeks postoperatively. Histologic evaluations comprising inflammation severity and new bone formation were blindly made on H&E-stained decalcified 6-µm sections. Results: At 1, 4, and 8 weeks aft…