Pain Control During Dental Treatment

Anaesthetic equipment

The commonest question asked of dentists is, “Will the treatment hurt?”

For the majority of patients injections of local anaesthetic prior to dental procedures are a totally effective and acceptable method of pain prevention for dental treatment. Significant improvements in ‘single use’ hypodermic needle design and manufacture over the last fifty years have helped this to be true.

The development of effective strengths of topical anaesthetic gel, to be applied prior to injection, also mitigates some of the discomfort.

The mainstay of local anaesthetic drugs has always been lignocaine hydrochloride. A small quantity of adrenalin is added which helps to localise the anaesthetic and stops it wearing off too quickly. If adrenalin inadvertently enters the bloodstream it causes palpitations which is unsettling to patients but fortunately it does not last long.

The alternative is to use Prilocaine with Felypressin. (An alternative vasoconstrictor to Adrenalin). The anaesthesia produced by Prilocaine is slightly less profound than that produced by lignocaine.

Articaine is a modern local anaesthetic drug that has become the most popular in many countries. It produces anaesthesia that is both profound and long lasting. It has the advantage that in many cases it is so effective that regional block injections are not necessary. Some patients comment on the duration of ‘numbness’ but almost everyone would choose effective anaesthesia above all. We use articaine every day.

Patients occasionally ask if there is an antidote to local anaesthetic so that it could be ‘switched off’. Such a drug is not available but it would be interesting to speculate whether anyone would actually choose an additional injection of an additional drug at the end of treatment, instead of allowing the numbness to wear off naturally.

Over the years a variety of alternatives to conventional local anaesthetic injection been developed:

The concept of electronic nerve blocking has been proposed for fifty years. Trans-cutaneous nerve stimulation (TENS) is used to alleviate back pain. Electronic dental anaesthesia (EDA) systems are designed to block transmission of nerve signals in the pain fibres of oral nerves. I have used EDA and chose to be personally subjected to it. Unfortunately my experience was that, even when applied to the maximum level (in itself significantly unpleasant), dental stimuli continued to cause unacceptable levels of pain. EDA is best described as of limited use and we do not use it at all.

Iontophoresis is a technology that uses a low voltage electrical potential to help anaesthetic chemicals travel into tissues. It is unlikely to become a contender for routine clinical use. The “Wand” is a microprocessor controlled device with a handpiece that delivers local anaesthetic, at variable rates, via a needle. At one time this device gained some traction of popularity. Ultimately the experience of patients and dentists was that it simply did not deliver profound anaesthesia.

Jet injectors provide the very attractive concept of the needle-less injection. The local anaesthetic is delivered via a short burst of high pressure energy. This technology is widely used for mass immunisation programmes and works very well through skin. Jet injectors continue to be marketed today but patients report that the noise and pressure cause an unsettling shock. Dentists and patients also report a high incidence of bruising and much higher levels of postoperative pain than following conventional injections. The soft tissues in the mouth are clearly much more delicate than skin. Our partnerships’ personal experience, based on using the system on each other, led us to reject introducing it for our patients.

Anxious individuals may have a heightened perception of pain. For some of these patients small preoperative oral doses of the Valium type of anxiety reducing drugs are effective in improving tolerance of treatment. (This family of anxiolytic drugs are properly known as Benzodiazepines)

A variety of ‘alternative’ approaches are used to help anxious patients tolerate treatment. These include acupuncture and hypnosis. We are not experts in acupuncture but the concept of proposing acupuncture for needle phobics is, at best, amusing.

Historically dentists were trained to give general anaesthetics but this was never sensible or safe. General anaesthesia has not been used in the dental chair since the Poswillo report in 1990.

Situations such as complex wisdom tooth extraction, where a general anaesthetic may be indicated, should be treated by an oral and maxillofacial surgeon. The general anaesthetic should be administered by an anaesthetist in a clinic with its own intensive care unit.

For particularly anxious patients we now recommend intravenous sedation administered by an anaesthetist who specialises is sedation. The anaesthetist looks after the sedation so that the dentist can concentrate on the dentistry. We have never been advocates of the dentist performing both tasks. Patients who have sedation need to be collected by a responsible adult, escorted home and to be supervised and supported for a couple of hours afterwards.

We continue to investigate new alternatives and would always make sure that new approaches pass the “friends and family test” before adopting them routinely.