When a marine stern shaft is bent with shafting misalignment and stern bearing wear factors, etc., the sealing properties of a plane mechanical seal is declined with the increase of both contact pressure and temperature of sealing surface, so a spherical mechanical seal which can automatically adjust the contact state of sealing surfaces is proposed to replace the plane mechanical seal in order...

Inadequate apical seal is the major cause of surgical endodontic failure. The root-end filling material used should prevent egress of potential contaminants into periapical tissue. The purpose of this study was to compare the sealing ability of four root-end filling materials: white mineral trioxide aggregate (MTA), gray MTA, white Portland cement (PC) and gray PC by dye leakage test. Ninety-si...

The purpose of this study was to assess the influence of sealing of the screw access hole (SAH) on the fracture resistance of metal-ceramic implant-supported restorations. UCLA abutments were used to make 30 implant-retained mandibular molar restorations and divide equally into three groups: Group SRS: screw-retained restorations with SAH sealed; Group SRNS: screw-retained restorations with SAH...

INTRODUCTION The aim of this in vitro study was to compare polymicrobial microleakage of calcium enriched mixture (CEM) cement, mineral trioxide aggregate (MTA), amalgam, and composite resin as intra-orifice sealing materials. MATERIALS AND METHODS Seventy single-rooted mandibular premolars were instrumented and obturated by cold lateral compaction technique. The teeth were randomly divided i...

Aim: The purpose of this study is compare sealing ability of mineral trioxide aggregate (MTA) and Biodentine as root end filling material, and also to compare the effect of different retro preparation techniques i.e. conventional bur v/s ultrasonic tips on sealing ability of both the root end filling materials. Materials and Methods: Totally, 40 extracted human single rooted teeth were decorona...

Using alternative materials such as residual products from other industries to mitigate the negative effects of acid rock drainage would simultaneously solve two environmental problems. The main residual product still landfilled by sulphate paper mills is the alkaline material green liquor dregs (GLD). A physical, mineralogical and chemical characterization of four batches of GLD was carried ou...

The aim of this study was to compare two adhesive systems (OptiBond FL and OptiBond SOLO) used as a sole material for sealing pit and fissures on contaminated surfaces with respect to microleakage. After acid etching, 56 sound teeth were contaminated with 1microl of plasma and randomly divided into 8 groups (n = 7). The adhesives were light activated under two conditions (Optilux VCL-403 and VC...

OBJECTIVE This study was performed to determine in vitro the short- and long-term sealing ability of a recently developed silicon-based root canal filling material (Gutta-Flow). STUDY DESIGN Sixty human upper central incisors were divided into 3 groups (n = 20). The root canals were instrumented and obturated with laterally compacted gutta-percha and AH26 sealer (group 1), continuous-wave the...

Taking the viscosity-temperature relationship of the fluid film into consideration, a 3-D numerical model was established by ANSYS software which can simulate the heat transfer between the upstream pumping mechanical seal stationary and rotational rings and the fluid film between them as well as simulate the thermal deformation, structure deformation and the coupling deformation of them. Accord...

UNLABELLED The purpose of this study was to employ photographic evaluation to observe the presence or absence of bubbles in pit and fissure sealants Concise and Prisma Shield, at 7 days, 18 months, 36 months and 11 years after accomplishment of treatment. METHODS A hematoxylin-based staining solution was applied to the occlusal surface at the study periods, which allowed assessment of the sea...