Development of labeled magnitude scales for the assessment of pain of dentin hypersensitivity.

Aims: To develop and test labeled magnitude (LM) scales that are sensitive to variations in pain associated with dentin hypersensitivity (DH).

Methods: Qualitative methods were used first to obtain words that describe the pain of DH. Magnitude estimation was then used to determine the position of these descriptive terms by relative magnitude along four vertical LM scales. To assess their DH, patients used the four LM scales following dentin stimulation with 4°C and 25°C water. The LM scales were then compared to visual analog scale (VAS) ratings by using eight pain scenarios of varying severity. Finally, participants with DH completed the four horizontal LM scales and VAS after dentin stimulation with 4°C and 25°C water. Within-subject t tests were used for comparisons between scales and water temperatures, and between-subject t tests were used for comparisons between participants with and without DH.

Results: Participants showed comparable differentiation between 4°C and 25°C water on VAS and three of the LM scale measures. Responses on the fourth LM scale showed better differentiation than VAS between the two water temperatures. Participants used a greater portion of the LM scales than VAS when rating low-level pain scenarios.

Conclusion: LM scales were shown to provide some advantages compared to standard VAS when used to evaluate DH-associated pain. These advantages may be generalized to other low-level pain conditions.