Instrument Basics
What type of dental instrument is 204S classified as?
The cross-section of a 204S sickle scaler.
triangular
This angle (in degrees) is ideal for calculus removal.
70–80°
These types of strokes are used for scaling with the 204S.
short, controlled pull strokes
The 204S is primarily used to remove this type of deposit.
supragingival calculus
The 204S is primarily designed for these teeth.
posterior teeth
This part of the working end is pointed, making the instrument unsuitable for deep subgingival use.
the tip
The lower shank should be this relative to the long axis of the tooth.
parallel
This kind of pressure is applied during activation.
moderate to heavy lateral pressure
This describes how far subgingivally the 204S can be used safely in healthy tissue.
1–2 mm
True or False: The 204S is a universal curet.
False
The number of cutting edges on ONE working end.
two
This is the best method for selecting the correct working end.
checking for a parallel lower shank and curve around the tooth on distal side of tooth
Your angulation during insertion should be this
0–40°
This area of the mouth is where the 204S is the best for.
interproximal posterior surfaces
This part of the instrument contains the cutting edges and tip.
the working end
The 204S's functional shank must do this around the tooth to indicate the correct working end.
curve upward and around the tooth
This happens if the blade angle is too closed
burnishing calculus
When using the 204S, this direction do you pull the instrument.
coronally
True or False: A sickle scaler should be used for root planing.
False
This angle exists between the face and the lower shank of the instrument.
90°
This portion of the blade should contact the tooth during proper adaptation.
the tip-third
This happens if the blade angle is too open
tissue trauma
This happens when the point, rather than the lateral surface, contacts the tooth.
tissue trauma or gouging
The sickle scaler’s triangular cross-section makes it ideal for this specific task.
removing heavy calculus deposits