1. Gate toward Operative Dentistry
Dr. Hicham Nuaimi
BDS, PG Dip in Operative and Esthetic Dentistry
PGDip in Implantology
MClin in Operative and Esthetic Dentistry

2. What are the objectives of Restorative Dentistry

3. Restorative Operation
Non Cariogenic causes
Abrasion / abfraction of tooth structure
Erosion of tooth structure
Cariogenic causes:
Failure restorations
Initial / recurring decay

4. What do We mean by Tooth Preparation?
is the mechanical procedure for eliminating decay lesion and establish proper design for retention and resistance of dental restoration withdraw its functional and esthetical approach.

5. Categories for tooth preparation
Eliminate decay lesion
Function and Esthetic
Protect the pulp
Minimal invasive preparation
Categories for tooth preparation

6. surface that does not extend to external tooth aspects
Internal wall
surface that does not extend to external tooth aspects
Axial Wall
is an internal wall that is parallel to the long axis of the tooth
Pulpal Wall
is an internal wall that is perpendicular to the long axis of the tooth.

8. is a prepared surface, which extends to the external tooth surface
External Wall
is a prepared surface, which extends to the external tooth surface
Floor wall
is a prepared wall, which is perpendicular to the occlusal forces (occluso-gingival), as pulpal and gingival walls.

9. is that portion of a prepared external wall consisting of enamel
Enamel Wall
is that portion of a prepared external wall consisting of enamel
Dentinal Wall
is that portion of a prepared external wall consisting of dentin.

11. is the junction of 3 plane surfaces of different orientation
Line angle
is the junction of 2 plane surfaces of different orientation along a line
Point angle
is the junction of 3 plane surfaces of different orientation

12. How can design our Preparation??

13. Classifications Black’s classification Charbeneu’s classification
Sturdevant ’s classification
Baume’s classification
Mount and Hume s’ classification
Classifications

14. Black’s Classification
Class V
Class III
Class I
Class II
Class IV
Class VI

15. Occlusal two-thirds of buccal and lingual surfaces
Class I
Posterior Teeth
Occlusal surface
Occlusal two-thirds of buccal and lingual surfaces
Anterior Teeth
Lingual surface

17. Class II
Posterior Teeth
proximal surfaces

19. proximal surfaces without removal of the incisal angle
Class III
Anterior Teeth
proximal surfaces without removal of the incisal angle

20. Class III

21. on the proximal surfaces involves the incisal angle
Class IV
Anterior teeth
on the proximal surfaces involves the incisal angle

22. Class IV

23. On the gingival third of the facial surface for both dentition.
Class V
On the gingival third of the facial surface for both dentition.
Class VI
Tips of cups and incisal edges of teeth for both dentition

24. Charbeneu’s classification

25. Modification of Charbeneu’s classification
Class II: Cavities on single proximal surface of bicuspids and molars.

26. STURDEVANT ’S CLASSIFICATION
Simple cavity
cavity involving 1 tooth surface
Compound cavity
cavity involving 2 tooth surfaces
Complex cavity
cavity involving 2> tooth surfaces

27. Finn’s Modification
For
deciduous teeth

28. pits and fissures of the molar teeth
Class i
pits and fissures of the molar teeth
buccal + lingual pits of all teeth
Class ii
proximal surface of molar teeth
Class iii
proximal surfaces of anterior teeth

29. Cavities of the proximal surface of an anterior tooth which involve the restoration of an incisal angle
Class iv
Cavities present on the cervical third of all teeth of all teeth including proximal surface where the marginal ridge is not included in the cavity preparation
Class v

30. BAUME’S CLASSIFICATION

31. According to tooth surface Smooth surface cavities
Pit and fissure cavities

32. Mount and Hume’s Classification
They tried in 1998 to find classification according to conservative approach in the extent and complexity, which encourage tooth structure for healing

33. Size 1
involve minimally in dentin. Need for remineralization only
Size 2
involve moderately in dentin. Need for restoration that supported by dentine. Tooth is strong no need for support
Size 3
involve moderately in dentin, but the tooth is weakened according to splitting of cusps or incisal edges. Restoration need for support

34. bulk loss of tooth structure by caries extension
Size 4
bulk loss of tooth structure by caries extension

35. INITIAL AND FINAL STAGES OF TOOTH PREPARATION
Initial tooth preparation stage: Step 1: Outline form Step 2 Resistance form Step 3 Retention form Step 4 Convenience form

36. Final tooth preparation stage: Step 5 Eliminate any remaining infected dentin Step 6: Pulp protection, if indicated Step 7: Secondary resistance and retention forms Step 8: Procedures for finishing external walls Step 9: Final procedure--cleaning, inspecting sealing

37. Step 1 Remove weakened and unsupported enamel.
Design the cavity wall to occupy the final restoration
Remove weakened and unsupported enamel.
Preserving cuspal strength
Margins afford for good finishing

38. Step 2. Primary Resistance Form
Design walls to shape the final restoration and enable restoration withstand without fracture either tooth structure or restorative materials. BY

39. keep appropriate enamel thickness for preventing fracture
Primary Design
create box shape at the floor that aids tooth structure to resist occlusal loading.
create slightly round internal angles which reduce the stress concentration.
restrict the extension in the external walls to get strong cusp and ridge areas
keep appropriate enamel thickness for preventing fracture

40. Prepare round Internal Line angles

41. Step3: Primary Retention Form
Is the form to obtain resistance of dental restorative from displacement during mastication forces.

43. Step4: Convenience Form.
Is the step to provide a proper vision during decay removal.

44. Step 5: Remove any remaining enamel pit fissure infected dentin
old Restorative material
Remove any carious tooth Structure
Step 5:

45. Cases for removal old restoration

46. negatively the esthetic result 2nd caries
Default in restoration
Symptomatic pulp

47. The ingress of noxious products & bacteria through microleakage
Step 6: Pulp Protection
Galvanic shock
The ingress of noxious products & bacteria through microleakage
thermal changes conducted through restorative materials
ingredients of various materials

48. LINEAR USED FOR: protects the dentin from noxious agents fluids
Some thermal protection
LINEAR USED FOR:
Initial electrical insulation

49. Mechanical preparation
Secondary retention
etching
Mechanical preparation
Step 7

50. Mechanical preparation
Beveled Enamel Margins
Groove Extensions
pin, Amalgam pins
steps, Slots

51. Etching Retention
Enamel Wall Etching
Dentin Treatment

52. Step 8: Procedure for Finishing the External Walls
Finishing the preparation wall is the further development, when indicated, of a specific Cavo surface design & degree of smoothness or roughness that produces the maximum effectiveness of the restorative material being used.

53. Objectives: - 1) create the best marginal seal possible between the restorative material and the tooth structure. 2)afford a smooth marginal junction. 3) provide maximal strength of the tooth & the restorative materials.

54. Final preparation Cavo-surface angle
degree of smoothness or roughness of wall
Provide proper strength of restoration

55. Step 9: Final Procedure: Cleaning, Inspecting. & Sealing
The usual procedure in cleaning is to decay free. Preparation of visible debris with warm water from the syringe & then to remove the visible moisture with a few light surges of air from the air syringe .

56. Thank You.