3ObjectivesDescribe and identify the general characteristics of dental instruments.Discuss variations in instrument shank length, curvature, flexibility, and blade-to-shank angulation.Identify a given instrument by its classification, design, number and manufacturer’s nameSelect the appropriate instrument for a given task.Discuss proper instrument blade adaptation and angulation.Compare and contrast the metals used in instrument construction.Compare scalers and curettes.
4Objectives Cont. Compare universal and area specific curet. Describe the distinct characteristics of a scaler.Describe the distinct characteristics of a curet.Determine and descrbe the correct cutting edge for each instrument in the cassette.Demonstrate proper adaptation, insertion, angulation, and activation of each instrument in the cassette.Evaluate successful instrumentation.
5Instrument Parts Handle Shank Working End- Blade Shape (straight or angled)FlexibilityLower or terminal shankWorking End- Blade
7Materials Used for Blade Stainless SteelMetalMaintains adequate sharpnessDo not rust or discolorCarbon SteelFeel sharper clinically and hold their sharpened edges longerMore brittle, can break more easily than SSTends to oxidize or rust*Gold “tipped”ExpensiveUsed for Implants*TeflonPlastic/Graphite reinforced nylonOnly used for Implants *See Darby page
24Design Characteristics: Basically there are 2 cutting edges at each end. The Face of the Sickle Scaler is at a 90 degree angle to the terminal shank.Flat “face”Terminal shank
25Note:You do NOT have an anterior sickle scaler in your cassette. You have a “posterior” sickle scaler – 204S (S204S7). We will use this instrument in the anterior and the posterior (universal). We will use this instrument on proximal (mesial and distal) surfaces only. We will NEVER use it on facial and lingual surfaces.
26Sickle scalers have a pointed tip and two cutting edges on each end of the instrument:
32Keep In Mind: Operator and Client Positioning Instrument Blade SelectionGraspFulcrum (Max. palm up, Mand. palm down)Insertion at 0°Adaptation open to 70°to 80°Angulation- maintain side of tip
33Please remember: The Sickle instrument is used SUPRAGINGIVAL! (You can go sub about 1-2 mm if necessary, but not more than that!!!)The Sickle instrument will be usedMesial & Distal!(You can NOT use on facial and lingual surfaces!!! )
35Anterior Scaler The above shows a straight shanked sickle. Initial point of insertion is always atthe line angleThe above shows a straight shankedsickle.Since we will not use this type ofinstrument, please focus instead onthe Terminal Shank and its cuttingedges and how it relates to the tooth.Tip 1/3 of the cutting edge of the instrument stays in contact with the tooth surface
37Mandibular Anteriors: Buccal Right Handed Clinician 564312#27#26#25#24#23#22From a 11:30 position, insert at the Distal Buccal Line Angle of #22 (tip towards the col)Initiate walking stroke towards and into the distal col. Remove at end of pull strokeReinsert at the Mesial Buccal Line Angle of #22 (tip towards the mesial col)Initiate walking stroke toward and into the mesial col. Remove at end of pull strokeMove onto #23 D and then #23 M, then #24D, #24 M, etc.
38Mandibular Anteriors: Lingual Right Handed Clinician #22#23#24#25#26#27From a 11:30 position, insert at the Distal Lingual Line Angle of #22 (tip towards the col)Initiate walking stroke towards and into the distal col. Remove at end of pull strokeReinsert at the Mesial Lingual Line Angle of #22 (tip towards the mesial col)Initiate walking stroke toward and into the mesial col. Remove at end of pull strokeMove onto #23 D and then #23 M, then #24D, #24 M, etc.
39Mandibular Anteriors: Buccal Left Handed Clinician 564312#27#26#25#24#23#22From a 12:30 position, insert at the Distal Buccal Line Angle of #27 (tip towards the col)Initiate walking stroke towards and into the distal col. Remove instrument at upward strokeReinsert at the Mesial Buccal Line Angle of #27 (tip towards the mesial col)Initiate walking stroke toward and into the mesial col. Remove instrument at upward strokeMove onto #26 D and then #26 M, then #25D, #25 M, etc.
40Mandibular Anteriors: Lingual Left Handed Clinician #22#23#24#25#26#27From a 12:30 position, insert at the Distal Lingual Line Angle of #27 (tip towards the col)Initiate walking stroke towards and into the distal col. Remove at end of pull strokeReinsert at the Mesial Lingual Line Angle of #27 (tip towards the mesial col)Initiate walking stroke toward and into the mesial col. Remove at end of pull strokeMove onto #26 D and then #26 M, then #25D, #25 M, etc.
42Notice that you will begin your working stroke at the 12121212Notice that you will begin your working stroke at theDistal Line Angle (1) and proceed into the distal col.You will then reinsert tip at the Mesial Line Angle (2)(tip now pointing towards the Mesial). Remember,Terminal shank of instrument is parallel to the line angle-proceed with walking stroke into the mesial col area.
43Auxiliary ShankTerminal ShankCorrect working end:
44Incorrect working end: Auxiliary ShankTerminal Shank
54Start at the distal line-angle with the tip facing distally.
55Do Not use thesickle on directbuccal/lingualsurfaces!!!
56Walking Sequence (per quadrant): (limited radius)Midline18.104.22.168.22.214.171.124.For Right Handed Clinicians:126.96.36.199.2.2.2.Notice that operator position and the direction of the instrument handle changes at the canine on the dominant side.188.8.131.52.184.108.40.206.220.127.116.11.2.1.
57Walking Sequence (per quadrant): For Left Handed Clinicians: (limited radius)Midline18.104.22.168.1.2.For Left Handed Clinicians:22.214.171.124.126.96.36.199.2.Notice that operator position and the direction of the instrument handle changes at the canine on the dominant side.188.8.131.52.184.108.40.206.220.127.116.11.1.2.
58Summary You will be using the Posterior Sickle on ALL proximal surfaces in the mouth.When you are scaling only the anterior teeth- please follow the sequence in slides (slides #44-45)When scaling posterior and anterior teeth in a single session- instrumentation sequence is:quadrant at a time! (slides #44-45)
59In Review You Should ALWAYS Keep in Mind: Lateral PressureStrokesStroke DirectionStroke LengthReinforcement
61The Universal curet is similar to the Sickle in that it also has two cutting edges per end. The difference between them is that the tip of the Universal curet is rounded- not pointed like the Sickle.This allows you to use this instrumentSUBGINGIVAL!!!
62Universal Curets: Scalers - (in cross-section) pointed tip pointed backsupragingival calculus removalCurets (in cross-section)rounded tiprounded backsub & supragingival calculus removal
63Universal Curets Columbia 13/14 (SC13/147) Barnhardt Younger Good Blade size, shank length and design will determine preferred area usage.
64So, Let’s Keep in Mind. . .Fulcrum rest must be near, but not directly over the surface being scaled (fulcrum on same arch).Determine correct working end of instrument:Terminal shank parallel to MESIAL line angle of molarFoot of instrument curves towards the toothAngle for insertion is 0-40 (closed blade)
66ContinuedWith closed blade, insert subgingival to JE- lateral pressure should be fairly light.Open angle to 45-90° (subgingival) and initiate exploratory stroke (pull stroke)Lateral pressure against tooth should remain fairly light unless a ‘bump’ is felt. Return back to JE and apply firmer pressure during pull stroke to remove ‘bump’ calculus?Fulcrum pressure increases during pull stroke
67Continued. . . Relax fingers during exploratory stroke Apply greater lateral pressure during pull stroke.Strokes should be short and controlled, with moderate pressure from the base of the pocket, toward the gingival margin.Stroke direction – vertical, oblique & horizontal (overlapping) remaining primarily in the gingival sulcus.
68Please remember… You should ALWAYS scale a tooth to completion!!! That means: Look at the clock and budget your time!!!How long will it take you to scale a lingual/buccal surface?Dependent on : How ‘heavy’ the calculus isHow ‘tenacious’ the calculus isHow good is your technique?Then determine how many teeth you can scale thoroughly and completely with the amount of time you have. . .