Aim: Mechanical characteristics of tooth preparation along with luting agents are significant entities on the maintenance of fixed dental prostheses. This study aimed at assessing the retention of complete metal crowns luted with two different luting agents using two different preparation height. Methods: Forty human maxillary premolars were selected and prepared to receive complete metal crown...

The present study evaluated the efficacy of electronic foramen locators (EFLs) to control root canal working length during rotary instrumentation and to assess possible reliability variations of different working lengths. Forty-eight human mandibular bicuspids were randomly divided in 2 groups according to the used device, Root ZX II (RZX) and Propex II (PRO). They were further subdivided in 2 ...

The effect of a restored machined hybrid dental ceramic crown–tooth complex is not well understood. This study was conducted to determine the stress state crown using three-dimensional finite element analysis. Human premolars were prepared receive full coverage crowns and with resin cement. Then, teeth digitized micro-computed tomography scanned an optical intraoral scanner scanner. Three-dimen...

the complexation reactions between tl+ and pb2+ ions and crown ethers 12-crown-4(12c4), 15-crown-5 (15c5), benzo-15-crown-5 (b15c5), 18-crown-6 (18c6), dicyclohexyl-18-crown-6 (dc18c6) and aza-18-crown-6 (a18c6) were studied in 90% acetonitrile and 90% ethanol solutions at 25 °c, using an a.c. polarographic technique. the stoichiometry and stability of the complexes were determined by monitorin...

objective: a clinically feasible convergence angle in full-coverage crown preparations, meeting the requirements for proper retention and resistance forms, has always been a matter of interest for laboratory and clinical researches. this study aims to evaluate the angle in teeth prepared by both under- and post-graduate students at tehran university of medical sciences, faculty of dentistry, de...

The final hot strip profile is a superposition of the roll initial crown, the roll bending and flattening crown, the roll wearing crown and the roll thermal crown. In this research, linear regression models are proposed to predict the roll force, the roll wearing crown and the roll thermal crown using experimental data provided by Mobarake Steel Complex (MSC). The short beam theory based on ela...