Class II. cavity preparation
Defects affecting one or bot proximal surfaces of posterior teeth.
Symptoms
> No symptoms
> Increased sensitivity (cold, sweet
> Retention of food
open — the e:
> Bite sensitivity (when carious lesion is open
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Diagnosis
> Visual changes of tooth structure
> Transillumination
> Radiography
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Preparation - amalgam
> Conventional preparation acc. to the Black's
rules
Preparation -  adhesive materials
> Conventional preparation for composites
> Adhesive slot
> Tunnel preparation
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Conventional preparation
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Isthmus
Access to the cavity
From the occlusal surface
Through the undermined enamel
Separation using wooden wedges is usefu
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Pre op
Cavity border and extention for
prevention
American rule
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Zásada retence
> Kotvení pomocnou kavitou na žvýkací ploše kotvení na rybinu
> Obráceně divergentní preparací kavity aproximální
> Preparace rýh a zářezů
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Resistance
> No undermined enamel
> No sharp wedges
> Isthnus is 1/3 — 1/ 4 intercuspidal distance
> Anglebetween axial and gingival wall: 90° or 85°
> Width of gingival wall isl mm at least
> Thickness of the filling 2 — 4 mm (4mm cusp replacing)
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Excavation of carious dentin
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Finishing of cavity walls
> Red coded diamond bur
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Cavity control
> Goog light
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Isthmus
Matrix placement
> Matrix primarily is used when a proximal surface is to be restored
The objectives:
Provide proper contact Provide proper contour Confine the restorative material Reduce the amount of excess material
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Matrices
> Ivory I retainer Ivory 1
> Hawe Neos retainer Ivory 8
> Tofelmire matix and retainer
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Wedging
> Slip the matrix band over the tooth )apical to the gingiva margin — 0,5, - 1 mm)
> Tighten the matrix, check it with probe
> Place a wedge
> Turn the retainer % counterclockwise
> Contour the band
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Condensation of amalgam
Condensor — stamen is the best one
Power driven condensation
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How big the stamen should be?
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Base
> Zinkoxidphosphate cement
> Zinkoxidkarboxylate cement
> Glass ionomer cement
> Z
On pulpal walls only!
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Instruments
Preparatio
Fillim
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Finishing and polishin
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Sleeping well with class II.?
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