NBDE Part II - Operative Dentistry Exam Questions
and Answers
pH that enamel starts to demineralize - Answers-5.5 (critical pH)
.How do cells first attach - dextran or lextran? - Answers-dextran
. S. Mutans is involved in converting sucrose to dextran using enzyme
Glucosyltransferase.
.What helps in carious progression but it is not the primary initiator for caries? -
Answers-LACTOBACILLUS
.Best clinical determinant of root caries?
a) sensitivity to cold
b) sensitivity to sweets
c) soft spot on tooth - visual and tactile methods are used to detect caries - Answers-c)
soft spot on tooth - visual and tactile methods are used to detect caries
.T/F: remineralized teeth are stronger than regular enamel. - Answers-TRUE
reminieralized enamel is darker, harder, more resistant
.For a lesion in enamel that has remineralized, what is most likely true?
a) The enamel has smaller hydroxyapatite crystals than the surrounding enamel
b) The remineralized enamel is SOFTER then the surrounding enamel
c) The remineralized enamel is DARKER than the surrounding enamel
d) The remineralized enamel is ROUGH and cavitated - Answers-c) The remineralized
enamel is DARKER than the surrounding enamel
.Most inter proximal caries lesion happens where? - Answers-Just under/below contact
.What tooth is most likely to have occlusal caries? - Answers-Mandibular molar
.40 y/o patient with all 32 teeth. No cavities. Has stain and catch in pit of molar. What do
you do?
a) watch and observe
b) sealant
c) composite - Answers-a) watch and observe
.DMFT (decayed, missing, filled teeth) - Answers-Quantifies how the PERMANENT
dentition has been affected by dental caries
, no 3rd molars
.DMFS (decayed, missing, filled surfaces) - Answers-A more detailed index than DMFT
as it quantifies how each tooth surface has been affected by caries
3rd molars included
.DEFT (decayed, extracted, or filled teeth) - Answers-Quantifies how the PRIMARY
dentition has been affected by dental caries
.DEFS (decayed, extracted, or filled surfaces) - Answers-Quantifies how each surface of
the primary dentition has been affected by dental caries
.Which population has the most number of UNRESTORED caries? - Answers-Blacks
.Burs used for smoothing preps?
a) more flutes and shallow
b) more flutes and deeper
c) less flutes and shallow
d) less flutes and deeper - Answers-a) More FLUTES and SHALLOW (red burs)
.Bur used that converges F and L walls?
a) 245
b) 7901
c) 169 - Answers-a) 245
.What bur do you use to SHAPE convergent walls for amalgam? - Answers-169
.Which high speed bur gives a smoother surface? - Answers-Plain cut fissure bur
best cross cut fissure have a higher cutting efficiency
.Bur used for polishing - Answers-STEEL
.What do you NOT use when beveling gingival margins? - Answers-Tapered diamond
causes enamel fracture
.How do you bevel occlusal floor?
a) 12, 8
b) 15, 80 (Gingival margin trimmer)
c) 15, 95 - Answers-b) 15, 80 (GMT)
.What would cause displacement of odontoblastic processes?
and Answers
pH that enamel starts to demineralize - Answers-5.5 (critical pH)
.How do cells first attach - dextran or lextran? - Answers-dextran
. S. Mutans is involved in converting sucrose to dextran using enzyme
Glucosyltransferase.
.What helps in carious progression but it is not the primary initiator for caries? -
Answers-LACTOBACILLUS
.Best clinical determinant of root caries?
a) sensitivity to cold
b) sensitivity to sweets
c) soft spot on tooth - visual and tactile methods are used to detect caries - Answers-c)
soft spot on tooth - visual and tactile methods are used to detect caries
.T/F: remineralized teeth are stronger than regular enamel. - Answers-TRUE
reminieralized enamel is darker, harder, more resistant
.For a lesion in enamel that has remineralized, what is most likely true?
a) The enamel has smaller hydroxyapatite crystals than the surrounding enamel
b) The remineralized enamel is SOFTER then the surrounding enamel
c) The remineralized enamel is DARKER than the surrounding enamel
d) The remineralized enamel is ROUGH and cavitated - Answers-c) The remineralized
enamel is DARKER than the surrounding enamel
.Most inter proximal caries lesion happens where? - Answers-Just under/below contact
.What tooth is most likely to have occlusal caries? - Answers-Mandibular molar
.40 y/o patient with all 32 teeth. No cavities. Has stain and catch in pit of molar. What do
you do?
a) watch and observe
b) sealant
c) composite - Answers-a) watch and observe
.DMFT (decayed, missing, filled teeth) - Answers-Quantifies how the PERMANENT
dentition has been affected by dental caries
, no 3rd molars
.DMFS (decayed, missing, filled surfaces) - Answers-A more detailed index than DMFT
as it quantifies how each tooth surface has been affected by caries
3rd molars included
.DEFT (decayed, extracted, or filled teeth) - Answers-Quantifies how the PRIMARY
dentition has been affected by dental caries
.DEFS (decayed, extracted, or filled surfaces) - Answers-Quantifies how each surface of
the primary dentition has been affected by dental caries
.Which population has the most number of UNRESTORED caries? - Answers-Blacks
.Burs used for smoothing preps?
a) more flutes and shallow
b) more flutes and deeper
c) less flutes and shallow
d) less flutes and deeper - Answers-a) More FLUTES and SHALLOW (red burs)
.Bur used that converges F and L walls?
a) 245
b) 7901
c) 169 - Answers-a) 245
.What bur do you use to SHAPE convergent walls for amalgam? - Answers-169
.Which high speed bur gives a smoother surface? - Answers-Plain cut fissure bur
best cross cut fissure have a higher cutting efficiency
.Bur used for polishing - Answers-STEEL
.What do you NOT use when beveling gingival margins? - Answers-Tapered diamond
causes enamel fracture
.How do you bevel occlusal floor?
a) 12, 8
b) 15, 80 (Gingival margin trimmer)
c) 15, 95 - Answers-b) 15, 80 (GMT)
.What would cause displacement of odontoblastic processes?
