Selection Criteria Studies to be included in this narrative review came from a PubMed/Medline search using the terms "temporomandibular disorders," "orofacial pain," "temporomandibular joint," "whiplash," and "whiplash-associated disorders and motor vehicle accidents and motor-vehicle collisions." The search was restricted to the period between 1995 and 2009 and included English-language peer-reviewed journals. The authors stated that, according to the Quebec Task Force on Whiplash-Associated Disorders, published articles of methodological rigor on this topic were not published before 1993. Key Study Factor Whiplash following motor vehicle collision. Main Outcome Measure Frequency of temporomandibular disorder symptoms. Main Results The evidence from the literature search was summarized using the Oxford Centre for Evidence-Based Medicine Levels of Evidence (OCEBM Levels of Evidence Working Group. "The Oxford 2011 Levels of Evidence. " Oxford Centre for Evidence-based Medicine. http://www.cebm.net/index.aspx? o=5653). The rating systemof the Oxford Centre for Evidence-Based Medicine has A, B, C, and D grades of recommendations, with A being the highest grade. For a question about the etiology of conditions such as the association between whiplash following motor vehicle collision and temporomandibular disorder (TMD) symptoms, grade A is derived from randomized clinical trials or "all or none" studies with consistent findings. Conclusions Based on their review of the literature, the authors selected 6 references. Based on these studies, the authors gave a grade of recommendation A for the association between whiplash following motor vehicle collision and the frequency of TMD symptoms.