Whether a pain around your tooth is sharp and intermittent or a constant, dull ache, it is classed as a toothache. As a result, toothache causes are diverse, ranging from structural damage to serious infection. Here are the main toothache causes that dentists see, and treatments they can offer.


Cavities are one of the major toothache causes, and they develop after exposure to the acid produced by the bacteria in plaque. If you have poor brushing habits, you are more likely to suffer from cavities. Your dentist can treat toothache by filling cavities, and they can also advise you on how you might prevent them in the future.


Toothache can also be caused by infections, which typically result from severe tooth decay. You may also notice a foul taste in your mouth, swelling, or increased sensitivity to hot and cold temperatures. This infection might be treated with a root canal, though you might also need a course of antibiotics.

Receding gums

Receding gums may also cause toothache, especially in older age. When your gums recede, the increased exposure of sensitive areas of your tooth can make consuming hot or cold foods very painful. Deep cleaning or gum surgery may be offered depending of the severity of the recession.

Problems with fillings

If a filling is damaged by pressure from clenching your jaw or grinding your teeth, toothache can result. This type of toothache can sometimes be treated by repairing the filling, but it is possible that you will need a replacement.


Bruxism is excessive grinding of the teeth or clenching of the jaw, and this constant pressure or movement can damage the teeth. Your dentist can provide a custom-made mouth guard to help with toothache caused by bruxism.


One of the less common toothache causes is a crack in a tooth, which can result from playing contact sports or being hit in the mouth. If the crack is diagnosed early enough and does not extend below the gum, a root canal procedure could save the tooth.

To minimize your chances of developing toothache, always practice good dental hygiene. If you do experience pain, contact your dentist for advice and treatment immediately.


Dr. Gerald O'Connor B.D.S., N.U.I. (hons) (Principal Dentist & Owner)

Dr Gerald O’Connor qualified with honours from University College Cork in 1998, where he achieved his Bachelor of Dental Surgery degree and was awarded the Kerr Prize for Restorative Dentistry. Following his qualification, he spent 6 years gaining experience in a dental clinic in Essex before buying his own practice in 2004. Dr O’Connor quickly added a second location in 2006 and formed the Oak Dental Group.

After returning to Ireland in 2013, he set up Killiney Dental with his long-time partner Rosemarie. Gerald has a wealth of experience in dentistry with a vested interest in modern, evidence-based solutions. He enjoys implementing new dental treatments that are minimally invasive for patients without compromising their desire for an idealised smile. Dr O’Connor currently serves on the Irish Dental Association’s Quality and Patient Safety Committee. In his spare time, he enjoys films, music, fiction writing and being anywhere in sight of the sea.