RG Practice Exam Questions

what is the boiling point of water at sea level

100 degrees celcius

dentistry in the USA began to organize dental societies around the year

1840

in what year was the first commercial dental lab in the US established

1887

the melting temperature for pure gold is

1945 degrees

when was the CDT program instituted

1959

100degrees Celsius is equal to

212 degrees F

one inch equals

25.4mm

the maxillary 2nd molar develops from

4 lobes

approximately how many CDTs are there today?

4000-7000

The chemical symbol for gold is

Au

which Federal agency sets health and safety standards that apply to dental labs?

The Occupational Safety and Health Administration

class III occlusion occurs when

The mandibular arch or position of the mandibular arch is anterior to the maxillary arch

The system for measuring weight of precious metals and alloys is?

Troy

The certified dental technician program is administered by the

Trustees of the National Board of Certification (NBC)

when mixing acids for lab use, which sequence should be followed?

acid poured into water

when setting an anatomic or adjustable articulator, the position of the table depends upon the

amount of overjet or overbite

the expansion of casting investment materials increases as the

amount of water is decreased

tuberosity is

an eminence of bone at the end of the maxillary ridge

excess flow of solder may be confined by using

anti flux

what ingredient in an alloy may be hazardous to the technicians health if handled improperly?

beryllium

what adds hardness and gloss to dental waxes

carnauba

The prominence at the cervical 1/3 of the lingual surface of an anterior tooth is the

cingulum

Which of the following is a requirement for annual recertification of all active CDTs

continuing education

which metal, when contained in a dental alloy lowers the melting temperature of the alloy

copper

the ingredient in soluble impression plaster that makes it water soluble is

cornstarch

hydrocal is a type of

dental stone

what is the preferred term for the process of pickling

deoxidizing

the space between two teeth are called

diastema

one of the disadvantages of resin die materials is that they may

distort when heated

the space between the crests of the maxillary and mandibular ridges is the

freeway space

in malocclused cases, which of the following the the most important consideration: esthetics, cusp interdigitation, canine guidance, functional mastication

functional mastication

the ground terminal in any electrical equipment is always colored

green

in proper occlusion, cusps should

guide the direction of closure

heat treatment means

hardening or softening of any metal

A bridge to be soldered is invested in soldering investment to

hold the parts in position

the term overjet refers to the amount of

horizontal extension of the maxillary over the mandibular teeth

all of the following terms may describe the same surface of a tooth except: mesial, incisal, axial, proximal

incisal

reducing the amount of water when mixing investment will cause the resulting crown to be

loose

with which of the maxillary teeth does the mandibular second molar occlude

maxillary 1st and 2nd molar

baseplate wax is composed primarily of

paraffin

color is normally added to the methyl-methacrylate in the

polymer

The Federal Denture Act was enacted to

prevent "mail-order" dentures from being transported to or from unlicensed and/or unauthorized persons

which of the following is not a service of the NBC? continuing education, the recognized graduate program, news and technical publications, product testing

product testing

Which part of a flame will provide for the greatest heat and the least oxidation?

reducing zone

Alginate impressions are used primarily for

removable prothesis

lateral excursion is the

right and left movement of the mandibular arch

irregular mucous membrane found in the anterior 1/3 of the palate is called the

rugae

the most commonly used accelerator for the setting time of plaster is

salt

the bone surrounding natural dentition is

the alveolar bone

it is essential to use clean wax for any wax-up because

the debris in the wax can result in pits in the finished casting

the number 650 on a stick of solder indicates

the melting temperature

the two ridges that combine to form a transverse ridge are the

triangular

which type of gold would be used for most crown and bridge procedures

type III

For safety, tanks of compressed gas must be secured

upright

how often must a CDT apply for recertification

whenever his/her service is interrupted for more than one year