There is much debate regarding the use of pacifiers, but there is evidence to show that there are both pros and cons. PROS Contrary to popular … [Read More...]
First, wou may be given a local anesthesia to numb the area.
Next, the dentist will remove the decayed dental tissue, using a drill. Lasers can also be used to remove the decay.
A drill uses metal cones called burs to cut through the enamel and remove the decay.
They come in different shapes and sizes and the dentist will choose the ones that are right for the size and location of your decay.
There are two types of drills:
– a high speed drill (the one with the familiar whining sound), which removes the decay and the unsupported enamel of the tooth
– a lower speed drill, which is used in the dentin (the second layer of the tooth). It is used here because the dentin is softer than the enamel.
Once the decay is removed, the dentist will shape the space (the cavity) to prepare it for the filling.
If amalgam is the material used for the filling , the cavity must have a retentive form, for the filling to stay in place.
If composites are used for the filling , a bonding material will be used to bond the filling to the tooth, so the retentive form of the cavity is not essential (but some retentive zones must be created ).
The dentist may put in a base or a liner to protect the tooth’s pulp (where the nerves are). The base or liner can be made of glass ionomer, composite resin, zinc oxide and eugenol, or another material.
If a bonded filling is placed, your dentist will etch (prepare) the tooth with an acid gel before placing the filling.
Etching creates tiny holes in the tooth’s enamel and dentin.
The composite material fills in the holes as the dentist places the filling ( this type of retention of the composite is called micro-mechanical retention).
A bonding material also is used, so the filling bonds to the tooth in two ways :
– first, by filling in the tiny holes created by etching;
– second, by forming chemical bonds to the organic component of the tooth.
Composite adhesion (scheme and microscope image)
Bonded fillings can reduce the risk of leakage or decay under the filling.
Certain types of fillings get hardened by a special light. The dentist will apply the material in succesive layers, stopping each time to shine a bright light on the resin. This cures (hardens) the material and makes it strong.
Finally, after the filling is placed, the dentist will finish and polish the tooth, using burs, polishers or discs.