OBJECTIVES There is some evidence that the pH at the root surface is reduced by intracoronal placement of bleaching pastes, which is known to enhance osteoclastic activity. Therefore, it is recommended that a protective barrier be used over the canal filling to prevent leakage of bleaching agents. Glass-ionomer (GI) is commonly used as a coronal barrier before nonvital bleaching. Because minera...

introduction: the purpose of this study was to evaluate the sealing ability of dentin bonding agents in root canals obturated with gutta-percha and mta. methods: forty-five single rooted human premolar teeth were decoronated so that remaining root portions were 12 mm in length. the samples were divided randomly into three experimental (n=13) and two control groups (n=3). all teeth were instrume...

The purpose of this study was to evaluate gray mineral trioxide aggregate (MTA), white MTA, and Fuji II LC cement as coronal barriers to bacterial leakage. Seventy-eight, matched, human teeth were obturated with gutta-percha. In group I, 18 pairs received a 3-mm barrier of gray or white MTA. In group II, 18 pairs received a 3-mm barrier of gray MTA or Fuji cement. Three pairs were used as posit...

The term 'craniofrontonasal dysplasia' (CFND) was introduced by Cohen' in 1979 when describing a 14 year old girl with coronal craniosynostosis, hypertelorism, limitation of shoulder movement, and digital abnormalities. The child's mother was also affected. In the same volume of Birth Defects, Slover and Sujansky2 reported similar findings in three female sibs, both of whose parents had hyperte...

AIM To evaluate and compare the microleakage of various restorative materials used as coronal barriers between endodontic appointments. MATERIALS AND METHODS Eighty extracted human permanent posterior teeth were prepared for standardized access cavities with dimensions of 4 × 4 × 4 mm. The teeth were then randomly divided into four groups; Kalzinol, Caviton, GC Fuji IX and GC Fuji II LC. Afte...

The aim of this research was to verify clinically and histologically whether an excessively large horizontal and vertical gap distance of an implant placed into an immediate extraction socket would osseointegrate coronally at the implant-socket interface without primary flap closure, a bone graft, or a barrier membrane. An immediate implant and straight-profile healing abutment were placed at t...

To examine whether leukotrienes could increase blood-brain barrier permeability, rats were anesthetized and injected intravenously with Evans blue. Ten microliters of vehicle, of leukotrienes B4, C4, or E4, or of arachidonic acid was injected over 1 hour directly into the brain parenchyma. The percentage of the total surface area of Evans blue extravasation in a coronal section of brain centere...

Gutta-percha (G) and sealer do not resist coronal leakage. In this study, the effect of orifice plugs using dentin-bonding/composite resin(C) or IRM on coronal leakage was evaluated in vivo. Sixty-one premolar roots in three beagle dogs were instrumented and filled with G and AH 26(S), or G alone. The coronal 2 mm was replaced with C or IRM, or left untreated. The access cavities were kept open...