1. CHEN Zhi Wuhan University School of Stomatology
Operative Dentistry 2
CHEN Zhi
Wuhan University School of Stomatology

2. Definition of Operative Dentistry
Operative dentistry is
the ART and SCIENCE of the
diagnosis, treatment, prognosis of defects of teeth which do not require full coverage restorations for correction.

3. Indication of Operative Dentistry
Caries;
Malformed, discolored,
or fractured teeth;
Restoration replacement.

4. Program of Operative Treatment
Patient assessment
Examination and diagnosis
Treatment planning
Pain control: local anesthetic
Isolation of the operating field

5. Program of Operative Treatment
Cavity preparation
Matrix application
Preparation of materials
Insertion and carving of materials
Finishing and Polishing

6. Cavity Preparation
The mechanical alteration of a defective, injured, or diseased tooth in order to best receive a restorative material which will re-establish a healthy state for the tooth including esthetic corrections where indicated, along with normal form and function.

7. Cavity Structure
walls
angles
cavity

8. Classification of cavity
Class II
Class III
Class IV
Class V
Class VI
—G.V.Black in 1908

9. Cavity Simple cavity: only one tooth surface is involved.
Compound cavity: two surfaces are involved.
Complex cavity: three or more surfaces are involved.

10. QUIZ
TIME

11. Class 1
Class 6
Class 1
Class 4
Class 3
Class 2
Class 2
Class 5

12. Stages and Steps in Cavity Preparation
Initial cavity preparation stage
Final cavity preparation stage

13. Initial cavity preparation stage
Step 1 Outline form and initial depth
Step 2 Primary resistance form
Step 3 Primary retention form
Step 4 Convenience form

14. Final cavity preparation stage
Step 5 Removal of any remaining infected
dentin if indicated
Step 6 Pulp protection
Step 7 Secondary resistance & retention form
Step 8 Procedure for finishing external walls
Step 9 Final procedures

15. Initial cavity preparation stage
Step 1 Outline form and initial depth
Step 2 Primary resistance form
Step 3 Primary retention form
Step 4 Convenience form

16. Outline Form and Initial Depth Ⅰ
Definition:
placing the cavity margins in the positions they will occupy in the final preparation;
preparing an initial depth of 0.2~0.8 mm pulpally of the dentinoenamel junction position or normal root surface position.

17. Maxillary Class Ⅰ outline form

18. Mandibular Class Ⅰ outline form

19. Maxillary Class Ⅱ outline form

20. Mandibular Class Ⅱ outline form

21. Common Error

23. Outline Form and Initial Depth Ⅱ
Principles: without any exception
all friable and/or weakened enamel should be removed
all faults should be included
all margins should be placed in a position to afford good finishing of
the margins of the restoration.

24. Outline Form and Initial Depth Ⅲ
Features:
preserving cuspal strength
preserving marginal ridge strength
minimizing facio-lingual extension
using enameloplasty
connecting two close faults or cavities
restricting the depth of the preparation into dentin.

28. Initial cavity preparation stage
Step 1 Outline form and initial depth
Step 2 Primary resistance form
Step 3 Primary retention form
Step 4 Convenience form

29. Primary Resistance Form Ⅰ
Definition:
The shape and placement of the cavity walls that best enable both the restoration and the tooth to withstand, without fracture, masticatory forces delivered principally in the long axis of the the tooth.

30. Primary Resistance Form Ⅱ
Principles:
To utilize the box shape with a relatively flat floor to resist occlusal loading by virtue of being at right angles to mastication force;
To restrict the extension of the external walls (keep as small as possible) to allow strong cusp and ridge areas to remain with sufficient dentin support;

31. Primary Resistance Form Ⅲ
Principles:
To have a slight rounding of internal line angles to reduce stress concentration in tooth structure;
To provide enough thickness of restorative material to prevent its fracture under load.

32. Primary Resistance Form Ⅳ
Feature:
Box shape
Relatively flat floors
Inclusion of weakened tooth structure
Preservation of cusps and marginal ridges
Rounded internal line angles
Adequate thickness of restorative materials
Reduction of cusps for capping if indicated

34. Initial cavity preparation stage
Step 1 Outline form and initial depth
Step 2 Primary resistance form
Step 3 Primary retention form
Step 4 Convenience form

35. Primary Retention Form Ⅰ
Definition:
The shape or form of the prepared cavity that resists displacement or removal of the restoration from tipping or lifting forces.
In many respects retention and resistance form
are accomplished in the same cutting procedure.

36. Primary Retention Form Ⅱ
Principles: depending on the materials
Amalgam restoration:
developing external cavity walls that converge occlusally and dovetail design

37. The devotail design provide retention form
to the occlusal portion of the cavity.
The occlusal convergence of the walls offers
retention in the proximal portion of the cavity
against displacement occlusally.

39. Primary Retention Form Ⅲ
Principles: depending on the materials
Composite restoration:
a mechanical bond between the material
and conditioned, prepared tooth structure.

41. Initial cavity preparation stage
Step 1 Outline form and initial depth
Step 2 Primary resistance form
Step 3 Primary retention form
Step 4 Convenience form

42. Convenience Form Ⅰ Conception:
The shape or form of the cavity that provides for adequate observation, accessibility, and ease of operation in preparing and restoring the cavity.

43. Convenience Form Ⅱ Principles: Allow access for caries removal
Allow access for restoration placement
Allow access to margins for finishing,
evaluation and cleaning

44. Convenience Form

45. Final cavity preparation stage
Step 5 Removal of any remaining infected
dentin if indicated
Step 6 Pulp protection
Step 7 Secondary resistance & retention form
Step 8 Procedure for finishing external walls
Step 9 Final procedures

46. Removal of any remaining infected dentin if indicated
Definition:
The elimination of any infected carious tooth structure or faulty restorative material left in the tooth after initial cavity preparation.

47. Removal of dentinal caries using round burs and spoon excavators
A: use of a round carbide bur, with air coolant and slow speed.
B: use of spoon excavators.
Removal of dentinal caries using round burs and spoon excavators

48. Final cavity preparation stage
Step 5 Removal of any remaining infected
dentin if indicated
Step 6 Pulp protection
Step 7 Secondary resistance & retention form
Step 8 Procedure for finishing external walls
Step 9 Final procedures

49. Pulp protection Using liners or bases to protect the pulp or
to aid pulpal recovery or both.

54. Final cavity preparation stage
Step 5 Removal of any remaining infected
dentin if indicated
Step 6 Pulp protection
Step 7 Secondary resistance & retention form
Step 8 Procedure for finishing external walls
Step 9 Final procedures

55. Secondary resistance and retention forms Ⅰ
Most compound and complex cavity preparations require additional resistance and retention form.
The exception being those preparations that are very conservative.

56. Secondary resistance and retention forms Ⅱ
Mechanical forms
Cavity wall conditioning form

57. Mechnical form:
Proximal locks
Proximal slots

58. Proximal locks

61. Slot on gingival wall

62. Final cavity preparation stage
Step 5 Removal of any remaining infected
dentin if indicated
Step 6 Pulp protection
Step 7 Secondary resistance & retention form
Step 8 Finishing external walls
Step 9 Final procedures

63. Finishing the external walls Ⅰ
Definition:
is the further development of a specific cavosurface design and degree of smoothness that produces the maximum effectiveness of the restorative material being used.

64. Finishing the external walls Ⅱ
Objectives:
To create the best marginal seal possible between the restorative material and tooth structure;
To afford a smooth marginal junction;
To provide maximum strength of both the tooth and the restorative material at and near the margin.

65. The strongest enamel margin is that margin
which is composed of full-length enamel rods
that are supported on the cavity side by shorter
enamel rods, all of which extend to sound dentin.

66. Finishing the external walls Ⅲ
The design of the cavosurface angle
The degree of smoothness of the wall

67. The design of the cavosurface angle:
depending on the material
amalgam: 90°
composite: beveling 30°~ 40°

71. Final cavity preparation stage
Step 5 Removal of any remaining infected
dentin if indicated
Step 6 Pulp protection
Step 7 Secondary resistance & retention form
Step 8 Procedure for finishing external walls
Step 9 Final procedures

72. Final procedures
cleaning
inspecting
varnishing
conditioning

75. Program of Operative Treatment
Cavity preparation
Matrix application
Preparation of materials
Insertion and carving of materials
Finishing and Polishing

76. Matrix Application
Tofflemire Matrix System
Ivory Matrix System

77. Matrix retainer, Band & Wedge

79. Matrix in Retainer

80. Rounded instrument
such as a spoon
excavator
Contour Matrix

81. Matrix on Tooth

82. Occlusal View

83. Wedge place

84. Contour Band

85. Ready for restoration

86. Program of Operative Treatment
Cavity preparation
Matrix application
Preparation of materials
Insertion and carving of materials
Finishing and Polishing

87. Armamentarium Amalgam Capsule Amalgamator Squeeze Cloth
Amalgam carrier

88. Activate Mercury

91. Program of Operative Treatment
Cavity preparation
Matrix application
Preparation of materials
Insertion and carving of materials
Finishing and Polishing

92. Insertion and carving
Class Ⅰ
Class Ⅱ

93. Armamentarium Amalgam Condensers Anatomic Burnishers Carves
Cleoid or Discoid

94. Check condenser fit

95. First increment

96. Start with the smallest condenser

97. Step condenser over mass

98. Continue adding increment

99. Condense toward walls

100. Use alternative instruments

101. Overpacked

102. Create initial grooves

103. Create initial grooves

104. Carve to margin

105. Enhance grooves

106. Remove flash

107. Final shape and burnishing

108. Completed restoration

109. Initial Increment

110. Initial Condensation

111. Lateral Condensation

112. Overpacking

113. Marginal Ridge Condensation

114. Condense to Margins

115. Create Occlusal Embrasure

116. Occlusal Embrasure

117. Occlusal Embrasure

118. Occlusal Embrasure

119. Removing Ridge

120. Removing Band

121. Flash & Excess

122. Moving Excess

123. Check with interproximal carve

124. Instrument on Tooth Structure

125. Completed Restoration

126. Rubber dam removal

127. Program of Operative Treatment
Cavity preparation
Matrix application
Preparation of materials
Insertion and carving of materials
Finishing and Polishing

128. Polishing

129. Evaluate the restoration Class I
Verify that cavosurface margin can be seen
Flash
Underfilled
Voids
Check the overall shape of the anatomy
Look for bulky ridges that might be high
in occlusion

130. Evaluate the restoration Class II
Check proximal contact
Check flash and overhangs proximally
Check underfill proximally
Check outline form

131. Check Occlusion Check gently in centric occlusion
Evaluate carefully with marking paper
or ribbon in Miller forceps
Check gently in centric occlusion
Check all excursive movement

132. Strasbourg

133. Thanks