Authors' objectives:

The aim of this review is to provide a summary of existing evidence on prophylactic removal of impacted wisdom teeth, in terms of the incidence of surgical complications associated with prophylactic removal, and the morbidity associated with retention.

Authors' results and conclusions: Forty studies were included in the review: two RCTs, 34 literature reviews, and four decision analysis studies. One RCT in the UK focused on the effects of retained third molars on incisor crowding (predominantly a cosmetic problem) in patients who had previously undergone orthodontic treatment. The results of this trial suggested that the removal of third molars to prevent late incisor crowding cannot be justified. Another on-going RCT in Denmark compares the effects and costs of prophylactic removal of third molars with removal according to morbidity. So far, this trial has recruited 200 participants, and preliminary results indicate that watchful waiting may be a promising strategy. However, more data and longer follow-up of patients are needed to conclude which treatment strategy is the most cost-effective. It is also known that a trial is on-going in the USA but no results are available so far. The methodological quality of the literature reviews was generally poor, and none of the reviews was systematic. Conclusions from nine reviews on anterior crowding suggested that there was only a weak association between retention of third molars and crowding. Six out of 21 reviews with a more general scope also concluded that the prophylactic removal of third molars was unjustified. Twelve general reviews did not conclude with a clear message about the management of third molars. Three reviews suggested that prophylactic removal of third molars is appropriate, but these reviews were of poorer methodological quality than the majority of other reviews. Three out of four papers focusing on surgical management expressed uncertain conclusions relating to the prophylactic extraction of third molars. It is difficult to compare prophylactic removal of impacted third molars with retention in the absence of disease, partly because these two strategies are related to different types of outcomes. By using utility methods, four decision analyses made it possible to compare different outcomes directly in the coherent models. Although there were important differences in the structure and methods for estimating input values, the findings of the decision analyses (by two groups of researchers) consistently suggested that retention of third molars was cost-saving and more cost-effective compared with prophylactic removal of impacted third molars.

Authors' recommendations: There is no reliable research evidence to support the prophylactic removal of disease-free impacted third molars. Available evidence suggests that retention may be more effective and cost-effective than prophylactic removal, at least in the short to medium term.

Authors' methods: Systematic review

Project Status: Completed

URL for project: http://www.hta.ac.uk/1169

Year Published: 2000

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: England, United Kingdom

Organisation Name: NIHR Health Technology Assessment programme

Contact Address: NIHR Journals Library, National Institute for Health and Care Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK

Contact Name: journals.library@nihr.ac.uk

Contact Email: journals.library@nihr.ac.uk

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