CHAPTER 49 Pretest Flashcards
Matrix Systems for Restorative Dentistry
Which Matrix system used for CLASS II posterior restoration is the most common?
Tofflemire retainer/ Universal Band
What is the component of the Tofflemire matrix retainer that is always positioned in the mouth facing the gingiva called?
Diagonal Slot
A matrix must be used to create a temporary wall for which of the following classification of tooth restoration ?
Class II (2), III (3), IV (4)
The larger side of the universal matrix band loop is always directed toward which part of the tooth?
Occlusal One Third
What is one advantage of an AutoMatrix over a universal matrix?
No retainer to hold the band in place
Once the AutoMatrix band is positioned on the tooth, how is the band tightened?
A wrench turns the coil CLOCKWISE to TIGHTEN the band
If a cusp is lost during preparation, which matrix band would provide the best support while restoring?
Extension - used for deeper Class II preparation that require gingival extensions to compensate for the loss of a cusp.
The Tofflemire retainer is often positioned in which area of the mouth?
On the buccal surface of the tooth being restored
Where should the cervical margin of a matrix band lie?
1mm BELOW the gingival margin of the preparation
Which type of circumferential matrix system is used for the primary molars
T- Band
The ___ Is used to decrease the size of the matrix band loop after the band has been placed on the tooth.
Inner Knob
If a restoration is not contoured properly, it can result in an ?
Overhang
Where is the wedge positioned when placing a posterior restoration ?
Lingual
Statement that is correct about wedges ?
The wedge presses the band against the tooth, causing a slight separation of the teeth
Triangular and the wooden wedges are the most used
What is the component of the Tofflemire matrix retainer that holds the matrix band securely in the device called?
Spindle
What us the material of choice for a universal 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
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 band and the wedge
