Trial of Nano-hydroxyapatite-Containing Toothpastes for Relief of Dentin Hypersensitivity

Not Applicable

Completed

Interventions: Device: 5% KNO3 toothpaste
Other: Placebo
Device: 15% nano-HAP toothpaste

Brief Summary: Subjects will be enrolled into 3 balanced groups each using a different strength toothpaste. Dental hypersensitivity (DHS) will be assessed at study start, midway and study end.

Detailed Description: This study is a double-blind, randomized, placebo-and positive-controlled, stratified parallel group clinical trial. The three groups will be randomly assigned to use one of three test toothpastes having an identical base formulation but containing respectively either 0% nano-hydroxyapatite (HAP) (placebo), 15% nano-HAP or 5% KNO3 (positive control). All dental examinations for data collection will be conducted by the same Clinical Examiner.

Recruitment & Eligibility

Inclusion Criteria

Males or females between the age of 20 and 80 years, of any socio-economic status
Diagnosed as having DHS, i.e. having at least one sensitive tooth with demonstrated cervical erosion/abrasion or gingival recession
Showing a sensitivity response to both tactile and cold air stimulus delivered by a Yeaple probe and a one-second blast of cold air respectively
Patients must be reliable, cooperative and of adequate intelligence to read and understand the rating scales and other study instructions
Patients must be able to read, comprehend, and sign the informed consent form
The teeth and sites to be tested should be on the buccal/labial surfaces of incisors, canines, premolars or molars where the affected sites are accessible
Teeth selected for testing should have a plaque index of ≤ 2

Exclusion Criteria

The sensitive tooth is associated with concomitant oral pain due to any other condition such as soft-tissue lesions, tooth-ache ascribable to dental caries, tooth fracture, or cracked tooth syndrome, or pain due to other surgical procedures or injuries.
The sensitive tooth is associated with a periodontal abscess as diagnosed from an X-ray or clinical examination of the tooth
The sensitive tooth is associated with mobility >1
The sensitive tooth is associated with gum pain from gingivitis, occlusal trauma, thermal or chemical burns
Patients having pain from periodontal-related causes but not DHS
Previous professional desensitizing treatment
Patients using medication which could interfere with the perception of pain
Medical histories marked by chronic use of anti-inflammatory agents, daily analgesics, anticonvulsants, antihistamines, antidepressants, sedatives and/or other psychotropic drugs
Pregnancy or breastfeeding
Allergies and idiosyncratic responses to toothpaste ingredients
Eating disorders or conditions associated with vomiting
Systemic conditions that are etiologic or predisposing to DHS
Excessive dietary or environmental exposure to acids
The sensitive tooth was restored in the preceding three months
The sensitive tooth is an abutment tooth for fixed or removable prostheses
The sensitive tooth has extensive restoration or restorations extending into the test area
Patients below 20 years or above 80 years of age
Smokers

Arm && Interventions

Group	Intervention	Description
Toothpaste 1	5% KNO3 toothpaste	Toothpaste 3 containing 5% potassium nitrate (KNO3) will be used by subjects to brush their teeth twice daily for 3 minutes in the morning and before bed each night using a 1 inch strip of toothpaste on a soft-bristled toothbrush.
Toothpaste 3	Placebo	Toothpaste 1 containing 0% nano-hydroxyapatite (HAP) will be used by subjects to brush their teeth twice daily for 3 minutes in the morning and before bed each night using a 1 inch strip of toothpaste on a soft-bristled toothbrush.
Toothpaste 2	15% nano-HAP toothpaste	Toothpaste 2 containing 15% nano-HAP will be used by subjects to brush their teeth twice daily for 3 minutes in the morning and before bed each night using a 1 inch strip of toothpaste on a soft-bristled toothbrush.

Primary Outcome Measures

Name	Time	Method
Measurement of Cold Air Stimulus	Week 0 (baseline), 4 weeks and 8 weeks	The primary efficacy outcome will be the decrease in cold air stimulus sensitivity (VAS score) from baseline to 8 weeks. Assessment of change in cold air sensitivity will be conducted using air delivered from a standard dental unit air syringe at room temperature (\~70°F±3°F)(\~21°C±2°C) and a pressure of 60psi (± 5psi). Assessment of sensitivity will be carried out using Visual Analog Scale (VAS). Tooth sensitivity was measured using a Cold Air Stimulus. When being assessed, participants rated their perception of the pain/discomfort experienced when cold air was directed at the exposed root of each tooth by marking a single vertical line on a Visual Analogue Scale (VAS) scale from 0 to 100 mm, where 0 = No Pain/Discomfort and 100 = Intense Pain/Discomfort.

Secondary Outcome Measures

Name	Time	Method
Measurement of Tactile Stimulus	Week 0 (baseline), 4 weeks and 8 weeks	The secondary efficacy outcome will be the increase in tactile stimulus force from baseline to 8 weeks. Assessment of Change in tactile sensitivity will be assessed using the Yeaple Electronic Force Sensing Probe.The explorer tip will be applied perpendicular to the tooth surface and a pressure load applied starting at 10 g and increasing to 80g. The load at which the subject says "yes" will be recorded. (Baseline screening will begin at 30g).