1. Lisa Mayo, RDH, BSDH Staci Janous, RDH, BS
DH 101: PRECLINICAL SCIENCES Mouth Mirror, Explorers, grasp Wilkins ch 38 Nield ch 2,3,4,5,6,7,12
Lisa Mayo, RDH, BSDH
Staci Janous, RDH, BS
NEED TYPODONT & CASSETTE IN CLASS!

2. Objectives Modified Pen Grasp, Palm Grasp, Fulcrum
Introduction To Instrument Anatomy
Mouth Mirror
Dental Explorers: Shepherd’s Hook & Explorer ODU 11/12
Using Clock Positions for Instrumentation

3. OBJECTIVE #1
Modified Pen Grasp
Palm Grasp
Fulcrum

4. Modified Pen Grasp
Nield p.71

5. Modified Pen Grasp
Nield p.77

6. Modified Pen Grasp
Nield p.77

7. Modified Pen Grasp: Finger Function
Nield p.72
Digits
Placement
Function
Index/Thumb
On instrument handle
Hold the instrument
Middle
Rests lightly on shank
Guide the working-end
Feels vibrations transmitted from working-end to shank
Ring
On oral structure, often a tooth surface
Advances ahead of the other fingers in the grasp
Stabilizes & supports the hand for control and strength
Little
Near ring finger
Natural, relaxed
No function in grasp

8. Correct Finger Placement
Rests on Ring Finger
Contacts Shank
Contacts Shank
Rests on Ring Finger
Rests on Tooth
Rests on Tooth
Contact Handle
Contact Handle
Handle rests
Handle rests
Contact Handle
Contact Handle

9. Nield p.75

10. Modified Pen Grasp: LF
Nield p.73

11. Modified Pen Grasp: RT
Nield p.73

13. Modified Pen Grasp
Palm Grasp

14. Palm Grasp Description
Handle of the instrument is held in the palm by cupped index, middle, ring, and little fingers
Thumb is free to serve as the fulcrum
Limitations of use
Instruments for calculus removal, root planing, and maintenance root debridement are not used with a palm grasp
Examples of uses
A/W syringe
Non-dominant hand for instruments stabilization while sharpening

16. Neutral Positions Nield p.92 Wrist Elbow Shoulder
Straight, and the forearm and the hand are in the same horizontal plane when in the neutral position
Elbow
90 degrees or greater, with the forearm positioned horizontally or slightly oblique
Hand is in straight alignment with the forearm
Shoulder
Neutral, both shoulders are level and relaxed to their lowest position
From a lateral position, each is vertically in line with, and beneath, each ear
The upper arms are straight down to the elbow

17. Nield p.91

18. WHICH ONE IS CORRECT?

19. Nield p.92

20. Nield p.92

21. Fulcrum
Nield p.89
Definition: The support, or point of rest, on which a lever turns in moving a body
Finger rest: The support, or point of finger rest on the tooth surface, on which the hand turns in moving an instrument

22. Fulcrum: Finger Rest Nield p.90 Objectives
Stability: controlled action of the instrument
Unit control: provides a focal point from which the whole hand can move as a unit
Injury prevention: to the patient’s oral tissues can result from irregular pressure and uncontrolled movement
Patient comfort: Confidence in the clinician’s ability ↑
Control of stroke length: limits the instrumentation to where it is needed

23. Nield p.90

24. Nield p.89

25. “Princess Wave” or Wrist-Rock
When instrumenting, wrist/hand/forearm should never break neutral position
Instruments are moved using the “Princess Wave” or “Wrist-rock” motion

28. OBJECTIVE #2 Introduction to Instrument Anatomy

30. Instrument Anatomy Each instrument is designed for different purposes
Clinicians know the names & numbers
Classification by purpose and use
Examination/Assessment Instruments
ex: probe, explorer, mirror
Treatment/Working Instruments
ex: curets, scalers, file, hoe, chisel

31. DENTAL MIRROR

32. DENTAL EXPLORERS

33. DENTAL PROBES

34. DENTAL SCALERS

35. Instrument Anatomy Wilkins p.580-581 Nield p187-199
Handle
Shank
Working End

37. 1. HANDLE Overall design Single-ended instrument 1 working end
Double-ended instrument
Paired (mirror image) or complementary working ends
Paired working ends are used for access to proximal surfaces from the facial or lingual aspects
Cone socket handles
Separable from the shank and working end
They permit instrument exchanges / replacements

38. 1. HANDLE Shape: Round or Hexagonal Solid or Hollow Metal or Silicone
Weight
Handles w/lighter weight: enhance tactile sensitivity, ↓ fatigue
Diameter
4 available: 3/8, 5/16, 1/4, and 3/16 inch
Ideal instrument: lightweight, serrated (next slide), hollow handle with a 3/8- or 5/16-inch diameter

39. 1. HANDLE Surface Texture/Serrations Smooth, Ribbed, Knurled
Texturing increases static friction between fingers & handle
Results in reduced pinch force in the grasp
No texturing
Decrease control of instrument in wet environment
Increase muscle fatigue
Raised texturing
Easier to hold in wet environment
Maximize control of instrument and reduce muscle fatigue

41. 2. SHANK Connects working end with handle
Shape, length, rigidity govern the access of the working end to accomplish goals of clinician
Lower / Terminal Shank
Section adjacent to the working end (cont’d next slide)
Blade
Shank
Lower Shank
Handle

42. 2. SHANK Lower Shank cont’d
Provides important visual clue’s for the clinician in selecting the correct working-end for the particular tooth you are working on
General rule of thumb: TERMINAL SHANK PARALLEL TO THE TOOTH for correct adaptation
Lengths
Standard
Extended: 3mm longer

44. 2. SHANK Shape Simple/Straight Flat Bent in one plane (front-to-back)
Anterior teeth
Ex: Anterior sickle scaler H 6/7, Gracey ½ (your instruments in clinic)
Complex/Angled/Curved
Shank bent in 2 planes (front-back and side-to-side)
Posterior teeth
Ex: Posterior sickle scaler 204S, Universal scaler 13/14, Gracey 11/12 or 13/14 (your instruments in clinic)

46. Nield p.194

47. 2. SHANK Flexibility Length
Varying degrees of thickness and rigidity that relate to the instruments purpose
Rigid/Thick Shank: stronger, able to withstand greater pressures w/out breaking. Needed for removal heavy calculus
Less Rigid/More Flexible Shank: More tactile sensitivity. Used for finer scaling, removal smaller deposits, exploring (feeling)
Length
Distance from working end/blade/cutting edge to junction of the shank & handle
Most instruments 35-40mm (1/2in)

48. 3. WORKING END Carries out the purpose/function of the instrument
Some instruments remove deposits, some are used just for assessment or feeling
To determine its use, need to know the parts of the working end

49. 3. WORKING END Nield p.197 Parts of Working End Cutting Edge
Fine line where 2 surfaces meet
Ex: face and lateral surface meet to form the sharp cutting edge of a curet
Lateral Surfaces
Meet or are continuous to form the back of the instrument
Face and Back
Purple = face
Gold = Back
Nield p.197

50. INSTRUMENT USE Instrument grasp functions
Dominant hand: hold and activate the treatment instrument
Nondominant hand: mirror, suction, syringes

52. OBJECTIVE #3
MOUTH MIRROR

53. Mouth Mirror Competency

54. Mouth Mirror
Uses
Indirect vision: Looking through the dental mirror to see areas of the mouth
Indirect illumination: reflecting light off dental mirror onto tooth/area
Transillumination: transmission of light through a sample.
Ex: detecting caries or enamel fractures by shining a specific light through the enamel
Direct vision: Looking directly with eyes into oral cavity

56. Nield p.93

57. Nield p.94

58. Nield p.94

59. Nield p.95

60. Nield p.95

61. CRACKED TOOTH & TRANSILLUMINATION YOU TUBE

62. Nield p.95

63. Nield p.94

65. Objective #4 Explorers: Shepherd’s Hook & ODU11/12
Nield CH 12 p

66. Explorers Designed for adaptation around the tooth
Used to detect and assess:
Supragingival calculus
Subgingival calculus
Cemental irregularities
Dental caries
Decalcification
Irregularities in margins of restorations
Secondary caries around restorations
Morphologic crown and root anomalies
External root absorption

67. Explorers
Made of flexible metal that conducts vibrations from working-end to clinician’s fingers resting on the instrument sank or handle
Circular in cross-section
Working-end 1-2mm in length (tip)
Do NOT use actual POINT to detect calculus,
use the SIDE
Nield p.281

68. Explorer Stroke Assessment or Exploratory Stroke
Require high degree of precision
Use LIGHT, CONTROLLED STROKES
Tactile Sensitivity
Ability to detect tooth irregularities by feeling vibrations transferred from explorer working end to handle

69. Insert assessment stroke
Nield p.279

70. Nield p.297 WRIST POSITION WHILE EXPLORING
More on Neutral Wrist Position at end of class
Nield p.297

71. Nield p.297

73. Shepherd’s Hook Competency
Point Value: 1
1. Uses Modified Pen Grasp
2. Uses proper fulcrum
3. Hand is straight with forearm
4. Keeps 1-2 mm of tip on tooth
5. Tip is angled 75°angle on groove/fissures
6. Repositions correctly as needed
7. Uses wrist to move instrument
8. Uses light but firm grasp
9. Mirror used correctly
10. Patient and operator position is correct
11. Light is positioned correctly
*12. Utilizes proper infection control protocol
TOTAL POINTS:

74. Shepherd’s Hook
Resembles the long stick with a curved end that was used by ancient shepherd’s to catch sheep
Uses
Supragingival examination of the margins of
restorations or to assess for sealant retention
Examine grooves and pits of teeth
NOT recommended for subgingival use

75. Shepherd’s Hook Technique Angled 45° onto tooth surface, not 90 °
Place explorer around grooves and in pits
Actual point not used
Keep 1-2mm of tip on tooth surface at all times

76. ODU 11/12 Competency

77. WHAT WE ARE DETECTING WITH ODU11/12
Nield p.298

78. WHAT WE ARE DETECTING WITH EXPLORING
Nield p.298

79. Nield p.299

80. SUBGINGIVAL CONDITIONS
INTEPRETATION OF
SUBGINGIVAL CONDITIONS
Nield p.299

81. Nield p.299

82. Nield p.300

83. SKILL BUILDING ANTERIOR
Nield p.284
NEED TYPODONT & ODU11/12
Correct Working End For Anterior Teeth = ODU11/12 Wraps Around the Surface You Are Exploring

84. SKILL BUILDING POSTERIOR
Nield p.288
Correct Working End For Posterior Teeth = ODU11/12 Wraps Around the Mesial Surface

86. Clock Positions & Instrumentation
OBJECTIVE #5
Clock Positions & Instrumentation
Nield p.47-52
Nield Video

87. Using Clock Positions for Instrumentation
To learn which sides of the teeth you clean from what clock position
RT-Handed
Anterior Surfaces Away/Towards
Posterior Surfaces Away/Towards
LF-Handed

88. Anterior Surfaces Away
RT clock position = o’clock
LF clock position = 12-1 o’clock

90. Anterior Surfaces Towards
RT clock position = 8-9 o’clock
LF clock position = 3-4 o’clock

92. Posterior Surfaces AwayL
RT clock position = o’clock
LF clock position = 12-2 o’clock L F

93. Posterior Surfaces TowardsL
Posterior Surfaces Towards L F
RT clock position = 8-9 o’clock
LF clock position = 3-4 o’clock

94. Patient Positioning
Be sure to have your patient turn their heads toward or away from you so you can gain better access and visibility to different areas of the oral cavity