a clinical method development study to characterise the efficacy of a dentifrice for the relief of dentin hypersensitivity

Conditions: Dentin Sensitivity

Summary: the aim of this study is to develop the clinical methodology to characterize the efficacy profiles of an experimental 5% potassium nitrate (kno3) and 0.454% stannous fluoride (snf2) combination dentifrice and a marketed desensitizing 0.454% snf2 only dentifrice for the relief of dentin hypersensitivity (dh), at multiple time points, over an 8 week treatment period.

this will be a single center, 8 week, randomized, controlled, examiner blind, two treatment arm, parallel design, stratified (by maximum baseline schiff sensitivity score of the two selected test teeth), method development study, in participants in good general health, with pre-existing self-reported tooth sensitivity, and at least two sensitive teeth (diagnosed clinically) that meet all study criteria at the screening and baseline (pre-treatment) visits.

Eligibility criteria:
inclusion criteria: * evidence of a personally signed and dated informed consent form (icf) indicating that the participant has been informed of all pertinent aspects of the study before any assessment is performed. * participant who is willing and able to comply with scheduled visits, treatment plan, and other study procedures. * participant in good general and mental health with, in the opinion of the investigator or medically qualified designee: a) no clinically significant and relevant abnormalities in medical history or upon oral examination. b) absence of any condition that would impact the participant's safety or wellbeing or affect the individual's ability to understand and follow study procedures and requirements. * male participant able to father children, or female participant of child-bearing potential and at risk for pregnancy, must agree to use a highly effective method of contraception throughout the study and for at least 5 days after the last dose of assigned treatment. female participant not of child-bearing potential must meet requirements as follows: achieved post-menopausal status, defined as follows: cessation of regular menses for at least 12 consecutive months, with no alternative pathological or physiological cause, and have a serum follicle-stimulating hormone (fsh) level confirming post-menopausal state, have undergone a documented hysterectomy and/or bilateral oophorectomy, have medically confirmed ovarian failure. * at visit 1 (screening): participant must have a) self-reported history of dh lasting more than six months but not more than 10 years. b) minimum of 20 natural teeth. c) minimum of 2 accessible non-adjacent teeth (incisors, canines, pre-molars), preferably in different quadrants, that meet all of the following criteria: signs of facial/cervical erosion, abrasion or gingival recession (ear), tooth with mgi score = 0 adjacent to the test area (exposed dentin) only and a clinical mobility of ≤1, tooth with signs of sensitivity, as evidenced by qualifying tactile (tactile threshold ≤ 20g) and evaporative air (schiff sensitivity score ≥ 2) sensitivity. * at visit 2 (baseline): participant must have a minimum of two, non-adjacent accessible teeth (incisors, canines, pre-molars), preferably in different quadrants, with signs of sensitivity, as evidenced by qualifying tactile (tactile threshold ≤ 20g) and evaporative air (schiff sensitivity score ≥ 2) sensitivity at both screening and baseline. all teeth which meet the sensitivity criteria (tactile threshold ≤ 20g; schiff sensitivity score ≥ 2) at screening (visit 1) should be assessed by tactile stimulus at baseline (visit 2). those teeth which meet the required tactile threshold (yeaple ≤20g) again at baseline should then be assessed by evaporative air stimulus. the examiner will select two 'test teeth' from those which meet the tactile threshold and schiff sensitivity score inclusion criteria at screening and baseline. once these two teeth have been identified, no further testing is necessary. test teeth should not be adjacent to each other and preferably in different quadrants. exclusion criteria: * an employee of the investigational site directly involved in the conduct of the study or a member of their immediate family; an employee of the investigational site otherwise supervised by the investigator; a gsk employee directly involved in the conduct of the study or a member of their immediate family. * participation in other studies (including cosmetic studies) involving investigational drug(s) within 30 days of study entry and/or during study participation. * participation in another tooth desensitizing treatment study within 8 weeks screening. * acute or chronic medical or psychiatric condition or laboratory abnormality that may increase the risk associated with study participation or investigational product administration or may interfere with the interpretation of study results and, in the judgment of the investigator, would make the participant inappropriate for entry into this study. * any condition which, in the opinion of the investigator, causes xerostomia. * pregnant female participant (as evidenced by a positive urine pregnancy test). * breastfeeding female participant. * known or suspected intolerance or hypersensitivity to the study materials (or closely related compounds) or any of their stated ingredients. * recent history (within the last year) of alcohol or other substance abuse. * dental prophylaxis within 4 weeks of screening. * tongue or lip piercing or presence of multiple dental implants. * gross periodontal disease, treatment of periodontal disease (including surgery) within 12 months of screening, scaling or root planning within 3 months of screening. * participant with evidence of gross intra-oral neglect or the need for extensive dental therapy. * teeth bleaching within 8 weeks of screening. * participant with fixed or removable partial dentures. * participant with fixed or removable orthodontic braces/bands or a fixed orthodontic retainer. * specific exclusions for test teeth: a) tooth with evidence of current or recent caries, or reported treatment of decay within 12 months of screening, b) tooth with exposed dentin but with deep, defective or facial restorations, c) teeth with full crowns or veneers, d) sensitive teeth with contributing etiologies other than erosion, abrasion or recession of exposed dentin, e) sensitive tooth not expected to respond to treatment with an over-the-counter dentifrice in the opinion of the investigator. * use of an oral care product indicated for the relief of dentin hypersensitivity within 8 weeks of screening (participant will be required to bring their current oral care products to the site in order to verify the absence of known anti-sensitivity ingredients). * daily doses of medication/treatments which, in the opinion of the investigator, could interfere with the perception of pain. examples of such medications include analgesics, anticonvulsants, antihistamines that cause marked or moderate sedation, sedatives, tranquilizers, anti-depressants, mood-altering and anti-inflammatory drugs. * use of antibiotics in the 2 weeks prior to the screening visit, or in the 2 weeks prior to the baseline visit during the acclimatization period. * daily dose of a medication which, in the opinion of the investigator, is causing xerostomia. * participant who requires antibiotic prophylaxis for dental procedures. * participant who is unwilling or unable to comply with the lifestyle/study restrictions described in the study protocol. * participant who has previously been enrolled in this study. * any participant who, in the judgment of the investigator, should not participate in the study.