#5 Flashcards
Spangberg and Langeland, ,1973
Biologic effects of dental materials
Toxicity of root canal filling materials on Hela cells in vitro
All materials are highly toxic when freshly prepared.
Kerr was less toxic than all others.
Chloropercha had the lowest toxic effect of all set materials.
Stanley and Lundy, 1972
Dycal therapy for pulp exposures.
Dentinal bridge forms in direct contact with Dycal in 23 days. Necrotic pulp is removed and replaced
Peciuliene, 2001, IEJ
Isolation of yeasts and enteric bacteria in root-filled teeth with chronic apical periodontitis.
IKI showed improved reduction in cultural microbes.
E. faecalis was a frequent isolate and showed resistance to traditional methods.
Torabinejad, 2002, OOO
Clinical implications of the smear layer in endodontics: A review.
Bacteria can penetrate into tubules up to 150 microns.
10 fold if SL is removed.
Current evidence supports the removal of SL after instrumentation.
Sen, 1995
The smear layer a phenomenon in RCT.
SL may slow y disintegrate around filling material or removed by bacterial by-products.
Ørstavik & Haapasalo 1990
Smear layer cannot serve as a strict barrier to bacteria. It only DELAYS the bacteria penetration
Yamada, 1983
Organic acids (e.g. Citric acid) are not as effective as chelating agents (e.g. EDTA) for the removal of smear layer
Thompson, 2000, IEJ
Overview of NITI alloys
Austenite at high temps or low press
Martensite at low temps or high press
Shuping, 2000,
Reduction of Intracanal Bacteria Using Nickel-Titanium Rotary Instrumentation and Various Medications.
Significant reduction in bacterial load seen after S3, showing that NaOCl requires a certain size of canal to become beneficial.
One week of CaOH significantly increases the number of negative cultures.
Goerig, 1983, JOE
The instrumentation of root canals in molar using step-down technique.
Allows instruments to enter w/o interference
flaring, eliminates dental irregularities and pulpal tissue.
Straight access
Sarkar, 2005, JOE
Physicochemical basis of the biologic properties of MTA
MTA is not an inert material, it is bioactive.
MTA releases all of its major cationic components, triggering the precipitation of HA on its surface.
Chemical composition of MTA
Portland cement: 75%
Bismuth Oxide: 20%
Gypsum; 5%
Love, 2001, IEJ
E. faecalis - a mechanism for its role in endodontic failure.
E. faecalis cells remain viable, and maintain the capability to invade dentinal tubules and adhere to collagen in the presence of human serum.
Invasion of dentin by bacteria was associated with cell adherence to type 1 collagen.
Siren, Haapasalo, 1997
Microbiological findings and clinical treatment procedures in endodontic cases selected for microbiological investigation.
Enterococcus faecalis was seen more probably in cases with several treatment visits, failed root canal treatment, failed or open temporary restorations, and in form of monoinfection.
Griffee, 1980
The relationship of Bacteroides melaninogenicus to symptoms associated with pulpal necrosis
Brannstrom, 1986, JOE
The Hydrodynamic Theory of Dentinal Pain: Sensation in Preparations, Caries, and the Dentinal Crack Syndrome
Drilling and probing can also produced an outward displacement of fluid in the tubules.
Heat applied to intact dentine activates the c fibers
Madison, 1988
An evaluation of coronal micro leakage in RCTT.
Not a good experiment.
Senia, 1971
the solvent action of NaOCl on pulp tissue of extracted teeth.
surface contact, volume and exchange of solution may limit the effectiveness of NaOCl as a tissue solvent.
No difference between 15-30 min
Safavi, 1990
Root canal dentinal tubule disinfection.
Use IKI for infected cases, flood canal for a few minutes.
Goldman, 1989
The usefulness of dye-penetration studies reexamined.
trapped air must be taken into account when doing ink penetration studies.
Traped air affects the penetration of ink
White and Hays, 1997
Residual Antimicrobial Activity After Canal Irrigation with Chlorhexidine.
On initial exposure chlorhexidine is at least as effective as sodium hypochlorite
CHC has substantive activity
Thompson and Dummer, 1997
Shaping ability of ProFile.04 Taper Series 29 rotary nickel-titanium instruments in simulated root canals
ProFile .04 taper series 29 rotary instruments prepared simulated canals rapidly, without creating blockage, only limited loss of length and with good taper and flow
Pre op canal shape didn’t affect any of the parameters investigated
Foreman and Barnes, 1999, IEJ
A review of CaOH.
calcium ions in the repair tissue does not come from the CaOH but prom the dental pulp.
Pisanti and Sciaky, 1964
calcium ions present in the applied calcium hydroxide do not become incorporated in the mineralized repair tissue which derives its mineral content solely from the dental pulp.
CaOH is an initiator rather than a substrate.
Pashley, 1990
Clinical considerations of micro leakage.
Mader, 1984, JOE
Scanning electron microscopic investigation of the smeared layer on root canal walls
