This research assesses the benefits and harms of the different ways to surgically remove wisdom teeth from the lower jaw. Removing wisdom teeth is one of the most common operations in dental surgery. Various techniques have been developed to carry this out, but which is the most effective? The review considered the following risks from surgery: pain after treatment, swelling, infection, the ability to open the jaw fully, damage to the nerves supplying sensation to the tongue and jaw fractures.
What was the research?
A systematic review of the evidence to find out the most effective way to surgically remove mandibular wisdom teeth.
Who conducted the research?
The research was conducted by a team led by Paul Coulthard, on behalf of the Cochrane Oral Health Group. Edmund Bailey, Marco Esposito, Susan Furness, Tara F. Renton and Helen V. Worthington were also on the team.
What evidence was included in the review?
Data was extracted from 35 randomised controlled trials. A total of 2,569 participated in the trials. The interventions fells into 7 broad categories, with many comparisons including only a small number of trials. The seven categories were:
- type of surgical flap raised
- use of refractors
- techniques for bone removal
- type of wound irrigation
- type of wound closure
- type of wound drainage
- complete or incomplete tooth removal
What did the evidence say?
The research found that slight changes to the position of the cut into the gum may reduce dry socket (infection) and pain after surgery. It is possible to protect a nerve to the tongue from damage by placement of a special surgical tool, however there were no good quality trials available to show that this reduces permanent nerve injury and the consequent loss of or altered sensations. Some surgeons will remove the top part of the wisdom tooth and leave the root in place when the root is close to the nerve in the jaw (supplying feeling to the lower lip and skin of the chin). Although it would seem likely that this should reduce the risk of nerve injury, the two trials which looked at this were of poor quality and had unreliable data.
How good was the evidence?
The quality of the 35 included trials was variable. None were assessed as being of low risk of bias. This was because most of the comparisons were based on a small number of trials and participants.
What are the implications for dentists and the general public?
Due to the poor quality of most of the trials in this review, recommendations for surgical practice are limited.
What should researchers look at in the future?
65% of the trials included in this review were at high risk of bias, therefore the authors recommend that future trials should correspond to CONSORT guidance on how to report clinical trials. There is a particular need for trials looking at partial removal of the tooth (coronectomy) versus complete tooth removal, with a long term follow up so that any adverse effects of this surgery can be determined.
Coulthard P, Bailey E, Esposito M, Furness S, Renton TF, Worthington HV. Surgical techniques for the removal of mandibular wisdom teeth. Cochrane Database of Systematic Reviews 2014, Issue 7. Art. No.: CD004345. DOI: 10.1002/14651858.CD004345.