Background: Authors of systematic reviews are required to identify all literature relevant to the review’s topic. Incomplete and insufficient indexing, especially of journals and articles not published in English, is a major source of retrieval bias. The German Cochrane Centre helps to reduce this problem by contributing to the Cochrane Collaborations global handsearching project, through which more than 20,000 randomised controlled trials (RCTs) and controlled clinical trials (CCTs) in medical and dental specialities have been identified and made available in The Cochrane Library (Blümle et al. Dtsch Med Wochenschr 2008; Blümle et al. Quintessenz 2008). Objectives: To find out to what extent dentistry is affected by insufficient electronic availability and indexing of journals/articles and is therefore prone to retrieval bias. Methods: Ten dental journals (241 volumes) were handsearched. Identified trials were compared with records included in MEDLINE. Results: a) 970 trials (407 RCTs, 563 CCTs) were identified; b) 514 trials (53%) were not included in MEDLINE; c) one journal was indexed over its entire publication period in MEDLINE, seven journals partly, two were not indexed at all; d) 26 (20%) of the 133 RCTs included in MEDLINE were tagged correctly, 15 as ‘Controlled Clinical Trial’, 12 as ‘Clinical Trial’ and 80 as ‘Journal Article’. 16 (5%) of the 323 CCTs included in MEDLINE were tagged correctly, five as ‘Randomized Controlled Trial’, 26 as ‘Clinical Trial’ and 276 as ‘Journal Article’. Conclusions: The indexing and availability of German dental journals is insufficient. Ninety-one per cent of the trials are tagged incorrectly and/or too unspecific. One reason could be too little trial information in English when the tags are assigned. Publishing handsearch results in CENTRAL, tagged as RCT/CCT, may reduce retrieval bias.