Clinical trial designs for testing of products for dentine hypersensitivity--a review.

Dentine hypersensitivity (DH) is a perplexing clinical entity. There is no doubt that patients self-report discomfort arising from various stimuli, but the highly subjective nature of the condition makes it extremely difficult to evaluate DH objectively. This is particularly true when evaluating the efficacy of desensitizing agents in the clinical trial setting. This paper attempts to provide an overview on clinical trial management to evaluate both in-office and over-the-counter (OTC) desensitizing agents. The importance of correct clinical trial design (type, allocation, blinding) with emphasis on patient selection, sample size, statistical power, duration, choice of positive/negative controls, treatment outcomes, and data collection, will be discussed.