Abstract
A research article (RA) abstract provides an overview or summary of the whole research. It is one of the most important sections in an RA since it is the first section researchers read to decide if the article is relevant to their research or not. Researchers need to know the intradisciplinary (within the same discipline) variations and similarities in the choice of Theme(1) and thematic progression (TP) patterns in RA abstracts in their discipline. Several studies have investigated variations and similarities in the use of Theme across disciplines. To the best of our knowledge, there is a lack of studies investigating intradisciplinary variations in the use of Theme in RA abstracts of dentistry subdisciplines. As epistemological differences exist between the various dentistry subdisciplines, it is pertinent to examine if there are intradisciplinary variations in the construction of Theme in the subfields of dentistry. The present study aims to investigate if there are any intradisciplinary variations and similarities in the use of Theme and TP patterns across seven dentistry subdisciplines: oral sciences, periodontics, endodontics, operative dentistry, prosthodontics, oral and maxillofacial surgery, and orthodontics. The study is framed by Halliday's systemic functional linguistics' approach to language and Danes's model for TP patterns. The findings revealed intradisciplinary significant differences between the subfields of dentistry in terms of the use of Theme types at p < .05 (p-value=0.0294), while there were no significant differences in the use of TP patterns and thematic markedness. Various interesting linguistic features characterizing the subdisciplines were found, although no significant interdisciplinary differences were found between dentistry RA abstracts and the findings reported in the literature of other disciplines. Finally, implications for novice dental researchers attempting to write an RA abstract are presented.