This article presents a comprehensive review of the literature on the diagnosis of pain in the orofacial region of patients suffering from a cognitive impairment or a dementia. This review was based on a literature search yielding 74 papers, most of which dealt with the assessment of pain in general in nonverbal individuals, for which several observational tools were developed. Unfortunately, none of these tools have been designed for the specific assessment of orofacial or dental pain. Thus, none of them can be recommended for use in the dental setting. There is hardly any information available in the literature on how to assess orofacial and/or dental pain in patients with a cognitive impairment or a dementia. Given the expected increase in the incidence of dementia over the upcoming decades, it is of the utmost importance that dentists can use well-tested tools that can help them in the diagnosis of orofacial and dental pain in this vulnerable patient population. Such tools should incorporate specific orofacial/dental pain indicators, such as the patient holding/rubbing the painful orofacial area, limiting his/her mandibular movements, modifying his/her oral behavior, and being uncooperative/resistant to oral care. Keywords: assessment, cognitive impairment, dementia, dentistry, orofacial pain