Advances in endodontic surgery.

Periradicular surgery is now increasing in importance as practitioners increase their knowledge and skill in saving teeth that were previously extracted. Many advances have occurred in recent years in both technique and materials. Tissue flaps should be designed with vertical releasing incisions and a wide base for optimal access and more rapid healing.

Surgical endodontic and retrograde procedures.

This article reviews the recent literature on endodontic surgery and root end filling materials. Root end filling materials have been studied extensively during the period of this review. The materials that have proved to consistently seal the apex in both leakage and success studies are the reinforced zinc oxide-eugenol cements such as IRM (The L.

Dissociation of cholecystokinin and pancreaticobiliary response to intraduodenal bile acids and cholestyramine in humans.

The role of intraduodenal bile acids in the regulation of cholecystokinin (CCK), pancreatic polypeptide (PP), and secretin as well as exocrine pancreatic and biliary secretion was investigated by means of a duodenal marker perfusion technique in volunteers. The following solutions were perfused: (1) liquid test meal, (2) test meal with 6 g cholestyramine, (3) test meal with 2 g chenodeoxycholic acid (CDC), (4) test meal with 6 g cholestyramine and 2 g CDC, (5) 6 g cholestyramine alone, and (6) 2 g CDC alone. The test meal caused an immediate increase in CCK and PP plasma levels, whereas secretin was not significantly altered.

The phylogenetic position of Peptococcus niger based on 16S rRNA sequence studies.

A 1330 base-pair fragment of a 16S rRNA gene has been amplified, cloned and sequenced. Comparison to other 16S rRNA sequences of eubacteria showed that P. niger represents a deep branch within the subdivision "Gram-positive with Gram-negative cell walls".

Retrograde filling materials: a retrospective success-failure study of amalgam, EBA, and IRM.

A retrospective study was done to compare the success rates of teeth with three different root end filling materials. The materials studied were SuperEBA, IRM, and zinc-free high-copper spherical amalgam. Radiographs of 488 cases from two geographically distinct offices were used, with the recall period ranging from a minimum of 6 months to a maximum of 10 yr.

Treatment of the endodontic emergency: a decade later.

A questionnaire was sent to diplomates of the American Board of Endodontics to determine changing trends in the treatment of endodontic emergencies since Dorn's survey 10 yr ago. There is a definitely greater trend toward complete instrumentation of the root canals to the apex regardless of the emergency condition than there was a decade ago. The number of respondents who leave teeth open when the pulp is nonvital has dropped dramatically in the past decade.

Comparative 16S rRNA oligonucleotide analyses and murein types of round-spore-forming bacilli and non-spore-forming relatives.

The phylogenetic incoherency of the genus Bacillus as presently described is demonstrated by analysis of both published and new data from comparative 16S rRNA cataloguing of nine Bacillus species and a number of related non-Bacillus taxa, i.e. Caryophanon latum, Filibacter limicola and Planococcus citreus.

Residues and effects from feeding high concentrations of hexachlorobenzene to broiler cockerels.

Eight-day old broiler cockerels received 0, 1, 10, or 100 ppm dietary hexachlorobenzene (HCB) for 25, 38, or 52 days. Treated birds grew faster for the first 25 days, but the trend was reversed at later times so there was no net weight difference at 52 days. Birds receiving 100 ppm dietary HCB had significantly enlarged adrenal glands at 38 days and enlarged livers at 38 and 52 days.

Effects and residues of dietary hexachlorobenzene in growing swine.

Crossbred weanling gilts were fed a standard ration containing 0, 1, 10, or 100 ppm purified hexachlorobenzene (HCB) for 13 wk. No mortalities, ill health, neurological disorders, or significant depressions in weight gain were observed. Postmortem examination revealed brightly fluorescent livers at all levels of HCB.