The dentist can use several methods to detect the presence of decay in a tooth. A visual examination can detect areas of decay as can a dental explorer. Areas of decay appear slightly discolored, if the dentist pushes on the area with a dental explorer it will often stick if it is decayed, while a healthy area of the tooth will resist the instrument. X-rays and laser fluorescence cavity detection aids can also be used. There are many factors that can make detecting cavities on an x-rays difficult, including previous restorations and the position of the decay. Laser fluorescence avity detection aids measure changes in the tooth structure. Cavity detecting dye is rinsed over the surface of the tooth. The dye will stick to areas of decay and rinse clean from healthy areas.
Teeth that have become worn, cracked or have decayed will require the placement of a filling.
After the need for a filling has been determined, the dentist will administer a local anesthetic to numb the area. Hand instruments, drills, lasers and air abrasion can be used to cut through the enamel and remove the decay. When using the drill (hand piece) the dentist will use a high-speed drill will be used to reach the dentin, once the softer dentin is exposed a low-speed drill will be used to remove the remaining decay.
After the decay is removed the dentist will shape the tooth for the filling. A liner may be placed to protect the pulp of the tooth. Some liners contain fluoride which is released over time to strengthen the tooth.
Before a bonded filing is placed the tooth will be etched. Etching creates small holes in the surface of the tooth to which the material can bond. This process is generally used when a composite filling is being placed.
After the filling material is placed the dentist will shape the filling using and drill and check the bite using bite paper to ensure that the filling is not too high, disrupting the patient’s natural bite pattern.
Sensitivity is common after the placement of a filling. It will usually last one to two weeks and is more common with composite fillings than with amalgam fillings. If the sensitivity lasts longer, the filling should be re-examined by the dentist, it may require adjustment or possible replacement.