How does dentist know how much to drill without an x-ray?
Mу son јυѕt came back frοm thе dentist wіth a bіg silver filling іn a permanent molar. Thе ѕtrаngе thing wаѕ thаt nο x-ray wаѕ taken. Thе dentist јυѕt felt around wіth pick аnd thеn dіd a lot οf drilling. Wаѕ thе cavity really аѕ bіg аѕ іt looks. Or dіd dentist drill extra tο guarantee hе gοt thе whole cavity?
An x-ray gives the dentist an idea how deep a cavity is; it will not tell him how much to drill. Doing a cavity depends a lot on tactile sense or feel. A cavity has a certain feel to it and healthy tooth structure has a distinct feel. That is the reason a dentist takes his explorer (aka "pick") to scrap the bottom of the tooth to see if all the decay has been removed. Color is not a good guide to use because healthy tooth material can also look dark or black.
Are you sure an x-ray wasn’t taken? Maybe within the last six months to a year? An x-ray that is six months to a year old is a valid x-ray for doing a filling. And often teens do not realize that an x-ray has been taken. Keep in mind too, that x-rays do not always show the extent of the decay. Dentists are often surprised by what they find when they open the tooth up.
A dentist will know when to stop drilling, because decayed tooth structure is soft and enamel is hard. He/she will drill out most of the decay, then use a special tool to scrape around inside the tooth to see if any more decay is present. If there is still decay present, more drilling will commence. Two different types of drills are used. One to open up the tooth and remove part of the healthy tooth structure to be able to get to the decayed part, then he will use a slower speed one to remove the decay. He may then go back to the high speed drill to make retentive grooves to hold the filling in place. What may seem like a very large filling to your untrained eye could, in fact be a normal sized filling.
When dentists use a drill they use it to get all of the decay from the cavity, it is obvious when it is all gone, then a filling can be applied.