How effective are painkillers in reducing the discomfort caused by orthodontic treatment?

Pain is a common side effect of orthodontic treatment. The pain resulting from orthodontic treatment may differ depending on the amount of force applied and the type of braces used. It may also change over the first few days following treatment. Pain has been ranked as the worst aspect of treatment and is the most common reason for people wanting to discontinue orthodontic treatment. Painkillers, swallowed or applied directly to the sore areas of the mouth following treatment, are thought to relieve the pain, making brace treatment more comfortable and acceptable. These painkillers are often cheap, readily available, easy to use and do not cause serious side effects.

What was the research?

A systematic review to find out whether painkillers, taken before or after orthodontic treatment, help to relieve pain. If so, which painkillers work best?

Who conducted the research?

The research was conducted by a team led by Aoife B. Monk of Liverpool University Dental Hospital on behalf of Cochrane Oral Health. Jayne E. Harrison, Helen V. Worthington and Annabel Teague were also on the team.

What evidence was included in the review?

We included 32 randomised controlled trials, with 3,110 participants. The participants were aged from 9-34 years. They were randomly allocated to groups to receive painkillers versus no treatment, painkillers versus a placebo, one painkiller versus a different painkiller or a painkiller taken at different time intervals. The severity of pain experienced by the study participants was compared. Nearly all the evidence was from adults who received oral painkillers versus no treatment, or one oral painkiller versus another oral painkiller. The main evidence that we found was on adults taking paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs). A small amount of evidence also investigated the effect of local anaesthetic and opioids (tramadol).

What did the evidence say?

We found evidence that paracetamol, NSAIDs, and local anaesthetic were all effective at reducing pain intensity at 2 hours, 6 hours and 24 hours following orthodontic treatment when compared with either a placebo or no treatment group. But we found no clear evidence of a difference between the effect of ibuprofen and paracetamol for reducing pain intensity at 2 hours, 6 hours or 24 hours following either the placement of separators (between teeth) or placement of an initial aligning archwire. We found some very low-quality evidence that ibuprofen taken 1 hour prior to separator placement significantly reduces pain intensity 2 hours afterwards when compared to ibuprofen taken post-treatment. However, at 6 hours and 24 hours, we detected no clear difference. There was no evidence of a difference between NSAIDs and local anaesthetic.

How good was the evidence?

The evidence available for the main outcome of pain relief is of moderate to low quality, whilst the quality of the rest of the evidence was very low. We judged only one study to be at low risk of bias.

What are the implications for dentists and the general public?

There is moderate-quality evidence that the use of analgesics reduces the pain associated with orthodontic treatment. Due to a lack of evidence, we remain uncertain whether NSAIDs are more effective than paracetamol, and whether topical NSAIDs are more effective than local anaesthetic, at reducing pain associated with orthodontic treatment. There is very low-quality evidence that the use of pre-emptive ibuprofen, taken one hour before orthodontic treatment, significantly reduces pain up to two hours after treatment; however, the effect appears to reduce over time, with no evidence of a difference at six hours and beyond.

What should researchers look at in the future?

In view of the quality of the available evidence, it is difficult to draw definitive conclusions regarding the relative effectiveness of different drugs, and whether taking an analgesic before treatment is effective. The results of this review imply that there is a need for more long-term, well designed and reported randomized controlled clinical studies to assess the efficacy of drug interventions with relation to NSAIDs and paracetamol.


Monk AB, Harrison JE, Worthington HV, Teague A. Pharmacological interventions for pain relief during orthodontic treatment. Cochrane Database of Systematic Reviews 2017 , Issue 11 . Art. No.: CD003976. DOI: 10.1002/14651858.CD003976.pub2 .

This post is an extended version of the review’s plain language summary, compiled by Anne Littlewood at the Cochrane Oral Health Editorial Base.