Ask the Dentist: Why does my tooth feel worse after I've had a filling?

There are sound reasons why you think your tooth feels worse after getting a filling, explains Lucy Stock of Gentle Dental Care

Normally teeth with fillings settle down, but there can be some discomfort for a time
Normally teeth with fillings settle down, but there can be some discomfort for a time

You went into the dentist with a dodgy tooth – a bit of it had broken off, though it wasn't painful – and now you've ended up getting a filling, leaving the tooth feeling sore and with a sense of lingering discomfort.

This type of thing makes people feel as if the dentist has done something wrong. But all is not quite what it seems...

Pretend, for a moment, that the tooth is a potato that has a black rotten bit inside. The potato's outer skin represents a tooth's hard outer enamel. Often, a

tooth can look good, even perfect, to its owner but underneath there lurks a

nasty balloon of decay. As with a potato, it can seem fine on the outside but as soon as you peel off its skin you expose the black part.

To remove the bad black portion of the potato you must dig it out until all

you have left is a healthy white potato with a chunk missing.

It's the same when we are cleaning out a tooth; dentists drill out the soft brown decay until we hit hard dentine.

The inner part of a tooth contains a chamber with micro-arteries, veins and

nerves. This sacred space doesn't like being invaded by anything, especially

not bacteria which decay is packed full of.

If bacteria breach the nerve chamber, then the nerves and blood vessels are

annoyed, and this is what elicits pain. If the tooth nerve is overly affected by the decay, then it starts to die off and an abscess forms.

The decay occurs due to things like overeating sugar, acidic foods, a dry

mouth or a lack of effective cleaning. All the decay must be removed before

a filling is placed to plug the gap.

Sometimes the tooth is annoyed by the process, but the dentist must clean the decay thoroughly otherwise it will continue to grow and destroy the tooth.

Normally teeth with fillings settle down over time. Sometimes regenerative

soothing dressings can be placed to calm a tooth and rarely teeth need root

canal therapy to remove the nerve to help it settle down.