Local anaesthetic is usually used to numb the immediate area around the affected tooth or portion of gum tissue, as this helps to prevent the patient from feeling pain. General anaesthetic has an effect on the whole body and causes the patient to lose consciousness while the treatment is carried out; general anaesthetic is usually only used for highly invasive procedures because it carries more risks than local anaesthetic.

The vast majority of dental procedures are carried out under local anaesthetic; if general anaesthetic is needed, the procedure will be carried out in a hospital rather than a dental surgery. Local anaesthetic is used during procedures including tooth extraction and root canal treatment; most Kent dentists use injections to administer anaesthetics but they may also use creams and gels, especially if the patient is nervous or has a fear of needles.

Using local anaesthetic is an important part of dental jobs, as many procedures require the mouth to be numbed prior to the treatment; dentists receive special training to learn about anaesthetics.