#4

Question 1

Hancock, 2001, OOO

Answer 1

Bacteria isolated after unsuccessful endo treatment in a North American population.

• 54 teeth sampled with paper points and reaming of apical dentin.
• No difference in Scandinavian or North American population.
• Flora is mostly one or two strands of G+
• E. faecalis in 30% of cases.
• Greater amount of bacteria recovered when fill was 2-4 mm from apex or when pa lesion was > 5 mm.

Question 2

Cvek, 1992, EDT

Answer 2

Prognosis of luxated non-vital maxillary incisors treated with calcium hydroxide and filled 
with gutta-percha, A retrospective clinical study .
Periapical healing = 95% after CaOH
Four years later after obturation= 92%
Long term application of CaOH weakens root

Question 3

Rotstein, 1996, JOE

Answer 3

Histochemical analysis of dental hard tissues following bleaching.
bleaching materials may adversely affect the dental hard tissues and should be therefore used with caution.
teeth were immersed for seven days, which is not realistic

Question 4

Dorn and Gartner, 1990, JOE

Answer 4

Retrograde filling materials: a retrospective success-failure study of amalgam, EBA, and IRM
Amalgam success rate= 75%
Super EBA success rate= 95%
IRM success rate= 91%

Question 5

Helfer, 1972, OOO

Answer 5

Determination of the moisture content of the vital and pulpless teeth.
Pulpless teeth have 9% less moisture than vital teeth in calcified tissues.
Dog teeth were used period of 24 weeks.
no other effects were looked at.

Question 6

Magura, 1991, JOE

Answer 6

Human saliva coronal micro leakage in obdurated root canals. in Vitro.

Question 7

Torabinejad, 1995, JOE

Answer 7

Comparative Investigation of Marginal Adaptation of Mineral Trioxide Aggregate and Other Commonly Used Root-End Filling Materials
MTA provides better adaptation and seal than commonly used root-end filling materials.
MTA showed the smallest gap between material and dentin walls followed by amalgam.

Question 8

Pashley, 1986 JOE

Answer 8

Dentin Permeability, Dentin Sensitivity, and Treatment Through Tubule Occlusion.
Hydrodynamic theory; movement of dentinal fluid or tube contents occurs in response to tactile, thermal or osmotic stimuli.
Any treatment that occludes the tubules should reduce dentin permeability by producing a thin smear layer.
Potassium oxalate acts as desensitizing agent and tubule occluding agent with the inhibitory property of potassium on intradental nerves.