Basic rules of  the preparation od cavities:


 1. Access to the cavity (standard diamons, high speed handpiece)
 2. Outlines (prevention of extension in case of amalgam)
 3. Excavation of carious dentin (round bur or excavator, sloe speed)
 4. Retention (it means that the filling nmust not fall out)
 5. Resistance (the filling as well as the remaining tooth structure must  not breake)
 6. Finishing of the borders (we prepare the retentive border for compoiste materials, no retentive
bprder for glassionomers and amalgam, the red coded diamond bzr shloud be used.
 7. Final control – after washing and drying, good illumination.





Diamonds:


Black :extra coarse,

Green :coarse

Blue: standard

Red: fine

Yellow: extra fine

White: ultra fine




Handpieces:


Turbine. 300.000 rpm. For úpreparation of the outlines esp. in enamel, removal of old fillings


Micromotor: max 40.000 rpm. The handpiece can gear the rpm:


Blue :  1:1 (no to slow, no to fast)

Red:    1:5 to fast

Green: 1:1,7 or . 2,5 to slow.



Principle of the connection between the filing material and hard dental tissue:


Composite: micromechanical

Glassionomers: chemical

Amalgam: macromechanical