The aim of this study was to assess the quality of systematic reviews of effectiveness of interventions in dentistry. The Database of Abstracts of Reviews of Effectiveness and the Cochrane Database of Systematic Reviews were searched to identify systematic reviews examining the effectiveness of interventions for oral, dental and craniofacial disorders and diseases. Sixty-five reviews were identified and assessed independently by two reviewers. The area most frequently evaluated within the reviews was pain relief/prevention (20/65, 31%) followed by caries and oral medicine. The quality assessment of the identified systematic reviews highlighted key areas where improvements could be made. One major weakness of the reviews was that the search strategies employed were not always adequate. Only 12 reviews (19%) demonstrated an attempt to identify all relevant studies. Other areas of weakness include the screening and quality assessment of primary studies, the pooling of data and examination of heterogeneity, and the interpretation of findings. This investigation shows that the quality of systematic reviews in dentistry could be improved. If future clinical decisions are to be based upon systematic reviews, it is imperative that the reviews address clinically relevant, focused questions and follow a 'transparent', well-designed protocol.