R. G. Exam Study Guide # 10
What size of wire is a good choice for fabricating a wrought wire clasp?
.020 to .025
Shrinkage of dental gold upon solidification is closest to?
1.50% (1.25 to 1.75%)
How does a CDT keep their certification status?
12 hrs continuing education credit and pay your annual dues
What are requirements for becoming a CDT?
5 years field,, take RG Exam, then CDT 1 year school, then take RG Exam, then CDT 2 year accred. school, take R.G. Exam, then CDT
How many laboratory technicians are certified today?
6,000 to 7,000 ( NBC 6,500)
Dental laboratory school programs are accredited by what organization?
ADA
Materials containing ammonia or alcohol will produce harmful gas when mixed with?
BLEACH
The antidote for an acid burn is to apply a chemical neutralizer such as?
Baking soda
What is the motions of the jaws involving balance and working excursions?
Bennett movement
In selective grinding, the BULL(Buccal Upper Lingual Lower) rule is helpful in remembering to adjust which upper cusps?
Buccal cusps
Identify and describe the Curve of Wilson, Curve of Spee, Compensating Curve?
Curve of Wilson - the bilateral curve between the buccal cusps and lingual cusps. right - left Curve of Spee - Anterior to posterior Compensating curve - opposing side of curve of spee
Silver palladium alloys are melted with a?
Gas and oxygen flame
Class I occlusion is identified by what teeth characteristics?
MB of maxillary first molar occludes with MB of developmental groove of mandibular first molar.
Where are the holding cusps located?
Maxillary - buccal Mandibular - lingual
Which muscle opens the jaw?
Mylohyoid
When melting gold with a gas/air torch, which part of the flame should be positioned on the alloy?
Reducing zone
Which articulator gives a fair simulation of a patient' actual mandibular movements because of its adjustable features?
Semi adjustable
Stabilizing a mobile tooth or teeth with a fixed restoration is called?
Splinting
A reservoir is used to?
Supply additional molten metal to the casting
During the electroplating process, the copper block is known as the?
anode
What is the location of the interproximal contacts considering the buccal - lingual or the labial lingual areas?
anterior - incisal third posterior - junction of the occlusion and middle one third
What are the centric holding cusps for the mandibular first molars?
buccal cusps
Which incoming work should be treated according to approved infection control protocol?
cases not disinfected by the dental office, only know infected cases, cases of unknown states. EVERY CASE SHOULD BE TREATED!!!
Application of an anti-flux prior to soldering will?
confine solder flow to the desired area
The copper plating bath solution contains?
copper sulfate
What interference would cause errors in balance and working excursions?
cuspal contact on the balancing side
What causes shrinkage porosity in a dental casting?
diameter of sprue is too small or there is no reservoir
Shrinkage of casting alloys is primarily compensated for by?
expansion of the mold material
What is the function of the buccinator muscle?
facial expressions and aids in mastication
The landmarks for creating a posterior palatal seal are the?
fovea palatinae and hamular notches
Where is the greatest convexity on the buccal surface of the mandibular first molar?
gingival/cervical one third
What is a disadvantage of epoxy die materials?
heat makes it distort
When are tripod marks used in RPD?
helps to replace of or reorient cast back on survey table
What important identifying marks does the dentist put on bite blocks?
high lip line, midline, smile line , cusp line
What destroys retention of an upper complete denture?
ineffective post-dam seal
A box must be created in the tooth preparation when the case calls for which attachment?
intracoronal (inlay)
The impression material of choice for preliminary impression is?
irreversible hydrocolloid
What is the purpose of a protrusive check bite?
it checks condyle path inclination
How will too little water affect the fit of a cast crown?
loose
Where is the raphe palatine located?
midline of hard palate
Which angle does the buccinator muscle lie to the plane of occlusion?
parallel
A base metal casting alloy should be benched cooled to?
preserve its physical properties
What is the purpose of indirect retention?
resist rotation of RPD when eating sticky foods
What is the most accurate way to set teeth on an immediate denture?
set in natural position
What is the cause of rounded margins on a casting?
slow or incomplete burnout
What is the function of lingual cusps of the maxillary posterior teeth?
stamp/holding/ centric/stops
How does the Federal Denture Act serve the dental field?
state laws must be followed and the dentist to do labwork
"To uphold and advance the dignity, honor and efficiency of those engaged as operators of dental laboratories, to advance their standards of service to the dental profession and to establish cooperation among its members" is the?
state purpose of our national organization
On a cast gold crown the sprue should be attached to the?
thickest area
How will too much water affect the fit of a cast crown?
tight
