A systematic review of Swedish research in orthodontics during the past decade.

The aims of this systematic review were to identify the study designs and topics of Swedish orthodontic articles, to elucidate their international position, and to verify in which scientific journals the articles had been published in the past decade. A search of the Medline database for papers published between 1992 and 2002 was made using the Medical Search Heading terms 'orthodontics', 'malocclusion', 'cephalometry', and 'facial bones and growth'. Two independent reviewers selected the articles of Swedish origin and categorized each article according to research design and principal topic. Overall, 15,571 articles in orthodontic research were found, and the Swedish contribution was 1.9% with the majority of these (71.5%) being submitted by universities. Most of the Swedish articles (84.5%) had been published in 10 journals and many high-quality studies with orthodontic interest were published in non-orthodontic journals with higher impact factor scores than the orthodontic journals. Every second study was prospective, and of these, 15 (5.2% of all Swedish articles) were randomized clinical trials (RCTs). It was found that nearly every third study, prospective as well as retrospective, was uncontrolled. The main classification was treatment studies (51.9%), followed by development (18.6%) and diagnostic information (10.7%) studies. Thus, the majority of the articles evaluated therapeutic interventions; however, although the RCT is the preferred study design in evaluation studies, few used this method. In an era focused on evidence-based medicine, studies with an RCT design will be the future challenge for research in the field of orthodontics.