Cons

Front 1

class 1

Back 1

Class I : Caries affecting pit and fissures on occlusal surface of molars , premolars and lingual surface of anterior teeth .

Front 2

class 2

Back 2

Caries affecting proximal surfaces of posterior teeth .

Front 3

class 3

Back 3

caries affecting proximal surfaces of anterior teeth without involving the incisal angles .

Front 4

class 4

Back 4

Caries affecting proximal including incisal angle of anterior teeth .

Front 5

class 5

Back 5

caries affecting gingival third of facial or lingual surfaces of anterior and posterior teeth .

Front 6

Class VI :

Back 6

Caries affecting cusp tips of molar , premolar and cusbids .

Front 7

original GV black classification

Back 7

it identifies the position of the lesion regardless of the size and extent of the lesion .

Front 8

Lesion site :

Mount classification

★site 1 :

★site 2 :

★site 3 :

Back 8

★Site 1 : the pits and fissures on the occlusal surface of posterior teeth .

★Site 2 : the contact areas between any pair of teeth . ( anterior or posterior

★Site 3 : the cervical areas related to the gingival tissues including exposed root surface .

Front 9

Lesion size :

Mount classification

size 1,2,3,4,

Back 9

※Size 0 : the initial lesion at any site that can be identified but has not yet resulted in surface cavitation .

※Size 1※ : the smallest minimal lesion requiring operative intervention .

※Size 2※: a moderate sized cavity .

※Size 3※ : the cavity needs to be modified and enlarged to provide some protection for the remaining tooth structure .

Size 4※ : the cavity is extensive following loss of a cusp in posterior teeth or an incisal edge from an anterior teeth .

Front 10

American dental association caries classification system ( 2008 )

Back 10

1.Sound

No surface change / or adequately restored

2.Initial Lesion

are limited to enamel or cementum Or outer most layer of dentin .

3.Moderate

Established , early cavitated , shallow cavitation .

4.Advanced

spread deep cavitation .

Front 11

Objective of cavity preparation :

Back 11

1 ) Removal all defects and provide necessary protection to the pulp .

2 ) Extend the restoration as conservative as possible .

3 ) Form the preparation so that the tooth and restoration not fracture under force of mastication .

4 ) Restore function and esthetics .

Front 12

Cavity preparation

※Initial tooth preparation stage

※Final tooth preparation stage

Back 12

Step 1 : outline form and initial depth

Step 2 : primary resistance form

Step 3 : primary retention form

Step 4 : convenience form

Step 5 : removal of remaining infected dentin or old restoration

Step 6 : pulp protection if nedded

Step 7 ) secondary resistance and retention form

Step 8 : finishing external wall

Step 9 : cleaning , inspecting and sealing

Front 13

•Resistance form

•Retention form

Back 13

★Resistance form : both the tooth and restoration can withstand the occlusal forces without fracture .

★Retention form : preparation resists displacement or removal of the restoration from tipping or lifting forces .

Front 14

restrict the pulpal depth of the preparation to a maximum

★0.2 mm into dentin in class I preparation,

★0.2-0.8 mm in class II preparation ,

★not more than 0.5 in class V preparation .

Back 14

T

Front 15

infected caries deeper than 0.5 mm in dentin should not be removed during this stage ..

Back 15

T

Front 16

The design features of the tooth preparation that enhance primary resistance form are

Back 16

1 ) flat floor .

2 ) box shape .

3 ) including of weakened tooth structure . 4 ) preservation of cusps and marginal ridges .

5 ) rounded internal line angles .

6 ) thickness of restorative material .

7 ) reduction of cusp for capping if indicated .

Front 17

The principles of primary retention form vary depending on the material used .

For amalgam : ..

.( macromechanical )

For composite : ....

In class V : ....

For cast metal restoration :

in class II......

Back 17

For amalgam : facial and lingual walls converging occlusally ( macromechanical )

For composite : micro - mechanical bond

In class V : retention grooves and cove .

For cast metal restoration : almost parallel opposing walls . Use of luting agent

Occlusal dovetail in class II .

Front 18

secondary resistance and retention form

Back 18

A ) mechanical features :

retention locks and grooves .

Slots .

Pins .

B ) bonding ( micromechanical )

Front 19

Several factors must be considered in the finishing of enamel walls and margins :

Back 19

1- Direction of enamel rods

2- Support of enamel rods

3- Type of the restorative material to be placed in the cavity

4- The location of the margins

5- Degree of the smoothness desired