CH 48 & 49
Where should the cervical margin of a matrix band lie?
1 mm beyond the gingival margin of the preparation
What is the correct order of steps for preparing the T-band matrix?1. Holding the free end of the band toward the facial, place the band loop on the tooth.2. Close the wings and pull the free end to make a small loop of the band.3. Bend the wings of the T-band to form a U shape.4. Slip the free end of the band through the U formation.
3,4,2,1
Mylar strips are used for Class ___ restorations.
III
what classification of restoration involves the proximal surface of a maxillary incisor and includes the incisal angle
IV
What is the final step in a cavity preparation?
Placing a desensitizing or lining agent
What is the purpose of a matrix system?
Provide a temporary interproximal wall for the restorative material
Which statement is correct concerning the purpose of the anterior matrix systems? (Select all that apply.)
The clear plastic allows the curing light to penetrate the material, completing the curing process. The matrix protects the adjacent teeth from the materials. The matrix helps in reconstructing the natural contour of the tooth.
Which statement is incorrect concerning veneers?
Veneers have an unlimited lifespan
To contour a metal matrix band for posterior teeth, place the band on a paper pad and rub the inner surface of the band with _____ until the ends begin to curl.
a burnisher or the end of a mirror handle
Once the AutoMatrix band is positioned on the tooth, how is the band tightened?
a wrench turns to coil clockwise to tighten the band
What is the internal surface of a cavity preparation that runs parallel to the long axis of the tooth called?
axial wall
For there to be a solid closure of margins on a posterior composite restoration, where should the prongs of the tension ring for the Palodent system be placed?
between the and and wedge
which statement is correct concerning wedges
both a wedge is used to apply pressure to the apical and gingival walls of the preparation and the wedge pressure to the band against the tooth causing a slight separation of the teeth
A matrix must be used to create a temporary wall for which of the following classifications of tooth restoration?
classes II, III, and IV
Which matrix system is used for anterior composite resin or glass ionomer restorations?
clear plastic matrix
What is the material of choice for restoring Class III and Class IV preparations?
composite resin
Which direct restorative material may be selected for the permanent restoration of a Class I lesion?
composite resin
which is an example of direct restorative dental material for a class II restoration
composite resin
The Tofflemire retainer that has been designed with a slight bend in the body to accommodate positioning from the lingual surface is known by what name?
contra-angle
What is the component of the universal matrix retainer that is always positioned in the mouth facing the gingiva called?
diagonal slot
Tooth whitening, or vital bleaching, is not indicated for a dental patient with which condition?
enamel hyperplasia
If a cusp is lost during preparation, which matrix band would provide the best support while restoring?
extention
A veneer is applied to which surface of a prepared tooth?
facial
during a class III restoration the dentist will enter the tooth from the lingual surface in order to reduce the size of the restoration form the ---- aspect
facial
A point angle is the junction of ______ walls or surfaces that are coming from a different orientation.
five
A comprehensive Class II restoration can involve as many as _____ surfaces of a tooth.
four
Who performs the majority of operative dental procedures?
general dentist
Where do Class V lesions occur?
gingival third
Which of the following is the instrument of choice when positioning a wooden wedge?
howe pliers
What is the fastest, most efficient way to whiten teeth?
in office treatment
Class III restorations involve the interproximal surfaces of which teeth?
incisors and canines
The ______ is used to decrease the size of the matrix band loop after the band has been placed on the tooth.
inner knob
A temporary restoration that can be placed in any tooth or tooth surface for a short period is also known as which type of restoration?
intermediate
which statement is incorrect regarding brush on whitening methods
it is effective as other tooth whitening methods
Where is the wedge positioned when placing a posterior restoration?
lingual
When one or both of the proximal surfaces are removed during a preparation, how is the filling material retained while restoring?
matrix system
Which of the following dental instruments is used to contour an anterior matrix band?
mirror handle
During a Class III or IV restoration, the dentist may use a _____ to help reproduce the correct contours and contact.
mylar matrix system
if a patient is having a class III restoration on the max central incisor which type of matrix system would be used
mylar system
Which condition listed is of greatest concern to the operator when preparing a Class V restoration?
nearness of the lesion to the gingiva
what is one advantage of an automatrix over a universal matrix
no retainer to hold the band in place
The larger side of the universal matrix band loop is always directed toward which part of the tooth?
occlusal one third
the universal or tofflemire retainer holds the matrix band snugly in position it is most often positioned in which area
on the buccal surface of the tooth being restored
How many tooth surfaces does a Class I restoration involve?
one
What is the component of a universal matrix retainer that serves to hold the matrix band securely in the retainer?
outer knob
which of the following is the step in the initial cavity preparation when the dentist decided on the design and initial depth of the sound tooth structure?
outline form
If a restoration is not contoured properly, it can result in an:
overhang
if a restoration is not contoured properly it can result in an
overhang
Which matrix system is used with posterior composite restorations?
palodent
a direct technique veneer is made of ---- and indirect technique veneer is made of -----
porcelain; composite
In which teeth are Class II restorations found?
premolars and molars
What is the dental assistant responsible for during a restorative procedure?
preparing mixing and transferring dental materials
What responsibility does the dental assistant provide during a permanent restorative procedure?
provide moisture control by using the high velocity suction
Which of the following is not an expanded function for a dental assistant?
retract the patients cheek and tongue
A plastic matrix strip is contoured by pulling the matrix lengthwise over the:
rounded end of cotton pliers
What is the component of the universal matrix retainer that holds the matrix band securely in the device called?
spindle
Which type of circumferential matrix system is used for the primary molars?
t band
Which of the following procedures is an example of esthetic dentistry?
teeth whitening
Which of the following statements is true?
the class V lesion location will determine the type of restorative material selected
Which statement is true regarding retention of pins?
the retention pin has deep threads that grip the dentin when screwed into the tooth structure
Which statement is incorrect concerning placement of the matrix retainer and band?
the seated band extends 2 to 3 mm above the occlusal surface of the tooth
complete the statement "when completing a permanent preparation, the dentist should have knowledge of:
the size and position of the pulp of the tooth
which statement is correct regarding posterior metal matrix bands
the smaller circumference is placed towards the gingica
Which of the statements is incorrect about a spot-welded band?
the spot welded band measures 3/4 to 1 inch of copper material
What is the material of choice for a universal matrix band?
thin flexible stainless steel
Why is a matrix band contoured prior to placing the restorative material?
to ensure that the final restoration will have proper contact with the adjacent tooth.
Which matrix system used for Class II posterior restorations is the most common?
tofflemire retainer and universal band
Which statement is incorrect concerning tooth whitening?
tooth whitening is permanent
Which statement is true?
when using retention pin one pin is placed for each missing cusp
which procedure listed is included under the umbrella of esthetic dentistry
whitening techniques