Introduction: Dentin hypersensitivity (DH) could be defined as a brief and sharp pain in response to thermical, chemical, tactile and osmotic stimuli, which cannot be attributed to any dental condition or pathology. Multiple therapies for the treatment of DH have been studied, including equivocal evidence about the efficacy of potassium nitrate salts and recent investigations a promising new 8% Arginin dentifrice.

Aim: The aim of this study is to compare the clinical effectiveness of 8% arginine/1450ppm sodium monofluorophosphate (D1) and 5% potassium nitrate/2500ppm sodium fluoride (D2) dentifrices in the treatment of dentin hypersensitivity.

Methods: Parallel-design, double-masked, randomized controlled clinical trial. Fifty healthy volunteers aged 18 to 70 years who attend at the Faculty of Dentistry , University of Chile, with DH and a visual analog scale (VAS) score ≥4 at least in two anterior and/or premolar teeth, will be selected and randomized into two treatment groups: T1 (n=25): 8% arginine/1450 ppm sodium monofluorophosphate dentifrice (D1); and T2 (n=25): 5% potassium nitrate/2500 ppm sodium fluoride dentifrice (D2). Environmental, dietary and oral hygiene habits will be recorded in a clinical chart, while O´Leary plaque index and dentin hypersensitivity (DH) measurements will be clinically assessed, at baseline, 4 and 8 weeks. DH will be evaluated through the mean VAS value in response to evaporative and thermal stimuli at baseline, 4 and 8 week follow-up. The data will be analysed through Stata® V11 program.

Inclusion Criteria:

• Age between 18 and 70 years
• Dentin sensitivity in at least 2 teeth (incisors, cuspids and/or bicuspids) with a VAS score ≥4
• Good general health

Exclusion Criteria:

• Defective or extensive restorations, deep dental caries, pulpitis, chipped teeth,
• Bridgework, dentures or crowned teeth that could interfere with the evaluation of hypersensitivity
• Pregnancy or lactation
• Ongoing treatment with anti-inflammatory or sedative drugs
• Systemic conditions that are etiologic or predisposing to dentine hypersensitivity, like chronic acid regurgitation
• Ongoing periodontal therapy or periodontal surgery in the preceding 3 months
• Allergic responses to the dentifrices
• Hypersensitivity treatment in the preceding 3 months