When amalgam teeth (mercury and silver mixture) are the most commonly used materials for tooth fillings, a drill had to be used to make a hole in the tooth, remove the bacteria and put the material for filling. This hole is generally much larger than the cavity intended to be repaired. If you are looking for the dentist then you can visit at https://www.cinemasmiles.com/.
The cavity doesn't look like before. Because of the use of fluoride, gear enamel has become stronger, harder and more resistant to bacterial attacks. However, the grooves on the surface chewing teeth is not hardened by fluoride because this groove does not have enamel in them.
Image Source: Google
The groove is narrower than the single fur on the toothbrush, so the method of brushing ordinary teeth does not succeed in cleaning the bacteria from this area. During the period of time this area is infected with bacteria, which then consumes their path to the dental nerve.
This cavity (tooth infection) does not appear on X-rays until many damage has been done on teeth. Most of the time this infection is not painful and not detected until the infection has done so much damage so that the nerves have been injured and patients need the treatment of root canal. In some cases, teeth can be very rotten, so no longer can be repaired and need to be withdrawn.