Objectives: The aim of this study was to determine the level of evidence that is published in the oral and maxillofacial radiology (OMR) literature. Methods: OMR papers published in Dentomaxillofacial Radiology and Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology and Endodontology between 1996 and 2005 were classified using epidemiological study design and diagnostic efficacy hierarchies. The country of origin and number of authors were noted. Results: Of the 725 articles, 384 could be classified with the epidemiological study design hierarchy: 155 (40%) case reports/series and 207 (54%) cross-sectional studies. The distribution of study designs was not statistically significant across time (Fisher's exact test, P 5 0.06) or regions (P 5 0.89). The diagnostic efficacy hierarchy was applicable to 246 articles: 71 (29%) technical efficacy and 166 (67%) diagnostic accuracy studies. The distribution of efficacy levels was not statistically significant across time (P 5 0.22) but was significant across regions (P , 0.01). Authors from Japan produced 26% of the papers with a mean ¡ standard deviation of 5.78 ¡ 1.98 authors per paper (APP); American authors, 23% (3.78 ¡ 1.72 APP); and all others, 51% (3.76 ¡ 1.51 APP). Conclusion: The OMR literature consisted mostly of case reports/series, cross-sectional, technical efficacy and diagnostic accuracy studies. Such studies do not provide strong evidence for clinical decision making nor do they address the impact of diagnostic imaging on patient care. More studies at the higher end of the study design and efficacy hierarchies are needed in order to make wise choices regarding clinical decisions and resource allocations.