The McGill Pain Questionnaire in dentistry: dental pain described in numbers

The McGill Pain Questionnaire (MPQ) is a verbal pain assessment tool allowing for the quantification of the intensity and quality of pain. However, describing dental pain (including both acute and chronic orofacial conditions causing pain) in single numbers may mask differential response patterns. That is, calculating Pain Rating Indices brings along the implicit assumption that the conditions under investigation are homogeneous with respect to words used to describe the pain. In the present study, a review of available literature was performed to assess the status of the MPQ in dental pain research. Forty-five studies were identified and examined, leading to the following conclusions. The MPQ's assumption that dental pain is one homogeneous condition is rejected. That is, dental pain may imply a variety of painful sensations. Using a statistical technique that incorporates all information regarding response patterns facilitates successful differentiation, and painful dental conditions being studied need to be as homogeneous as possible. Otherwise, describing dental pain in numbers masks differential response patterns.