Dental restoration
The restorative treatment is a part of dental practice and has to fix the goal carious lesions or other types of defects on individual teeth. It is also called conservative or restorative treatment.
- 3.1 Clinical Performance
- 3.2 Plastic filling materials 3.2.1 Procedure
- 3.3.1 inlays
- 3.3.2 onlays
Filling types
After G.V. Black are five different classes of cavity:
In addition, the fillings are distinguished according to the number of affected tooth surfaces in one-, two -, three -and multi- surface restorations.
Rules of filling preparation
Already Black has established criteria by which a charge must be formed:
Retention form
The filling must be shaped so that they will hold the tooth. When amalgam fillings that happens in that the cavity is prepared wider at the bottom than at the top.
Adhesively bonded fillings on a retaining mold is not necessary, since these panels will be " glued " to the tooth. It merely has to be ensured that the adhesive surface is sufficiently large.
Form of resistance
The filling must be shaped so that it can withstand the chewing pressure. However, the resistor shape refers not only to the filling but also on the tooth itself Thus, should have a sufficient "resistance" or stability after the preparation, the filling and the tooth.
Extension form
The filling should be shaped so that it includes the areas on which preferably forms caries ( predilection ). The slogan reads: " Extension for prevention " ( " extension for prevention " ) This last requirement is considered differentiated today.
Filling materials
A basic distinction is between plastic and rigid fillers.
Plastic filler materials are those which are introduced in a deformable state into the tooth and cured there. The remaining panels are shaped outside of the mouth and then inserted into the tooth.
Previously, this distinction was made between direct and inlays, but the CAD - CAM methods have led to therapies that work without impression, so actually the direct fillings should be included in, but just are not plastic fillings.
Clinical Performance
Plastic filling materials, which are cured by polymerization shrink by this step. This can lead to tension and very small gaps at the edge portions of the fill. Due to the more complex and more expensive inlays this problem is to be avoided. With inlay supplies is to distinguish between gold inlays, ceramic inlays and Compositinlays. Compared with composite fillings were no significant differences in durability was in a German study over eight years determined to ceramic inlays in a Danish Eleven -year study of an equivalent supply in comparison with composite inlays. A Swedish Eleven -year study evaluated a non-significant, lower failure rate of Compositinlays as the extra effort not apologetic.
Plastic filling materials
A classic example is the amalgam filling, which has been used for centuries. The amalgam fillings is indicated in the cavity classes I and II
More plastic filling materials are composite, compomer, glass ionomer cements and other as well as the gold foil filling. Of these, only the composite at adhesive bonding in Kaube congested area are indicated. Compomer and glass ionomer cements can be used for definitive restorations in not chewing congested area. All other cements find today only as a temporary filling materials use.
Procedure
If the decay is removed, the dentin must be closed. In shallow wells, this can be done by a paint job ( for example, with Copalharz ), at lower cavities is done by a cement filling ( usually zinc phosphate cement). In adhesively bonded fillings to supply the dentine is done by bonding.
If the decay is so deep that it penetrates into the immediate vicinity of the pulp, the dentin formation must be encouraged before placement of the filling through a calcium hydroxide - containing drug. This cover of the pulp by the drug called pulp capping; when the dentin is still preserved on the pulp, it is called indirect pulp capping, it is opened, it is called direct pulp capping.
For shaping the filling matrices, wedges as and other aids may be used.
Then freshly mixed silver amalgam is introduced in portions and condensed. The cavity is thereby overflowing and the excess then carved out again in tooth shape.
At the earliest after twenty-four hours the amalgam filling is fully cured and should be polished. The polish not only leads to a refinement of the surface, but reduces the surface by several orders of magnitude, thus reducing any pollution taxes to the same extent (diffusion laws).
For cavities classes I and II, the material is placed in a slight excess to pay off the oxygen inhibition while working out can also supply of composite or compomers. Alternatively, the formation of an oxygen inhibition can be prevented by the use of glycerine gel before curing. For the other classes of fillings can be prevented by hardening against the die the emergence of oxygen inhibition.
Inlays and partial crowns
Inlays
An inlay (also called inlay filling) is a filling made in the dental laboratory after an impression of the teeth, which fits exactly into the cavity. Examples are cast gold fillings ( gold inlays ) and ceramic inlays. Alternatively, an optical impression is taken and a computer-controlled Keramikfräsgerät a ceramic inlay milled from a blank.
Onlays
An onlay (also called dome filling) is the replacement of the defective, weakened tooth walls by reaching over the onlay on the cusp of the tooth bearing the bite force.
The transitions from the inlay on the onlay on the overlay up to the crown part are fluent.