The present study was designed as a randomised controlled clinical trial which was unicenter, double-blinded, parallel designed study, according to the Consolidated Standards of Reporting Trials (CONSORT) criteria, 2010. The study period was from July 2014 to September 2015.

90 Patients visiting the Out Patient of Department of Periodontology, Krishnadevaraya College of Dental Sciences and Hospital, Bengaluru, India, presenting with a chief complaint of dentinal hypersensitivity were enrolled in the study. Patients' age ranged from 18-60 years. The subjects interested in participating were explained in detail the treatment protocol. A verbal consent as well as a written informed consent was obtained from each patient Treatment of dentinal hypersensitivity with a combination of diode laser and potassium nitrate desensitising agent was considered as the test group and this was compared with diode lasers alone and desensitising agent alone as the positive control groups. The study was conducted in full accordance with the declared ethical principles (World Medical Association Declaration of Helsinki, version VII, 2013)13 and was approved by the Institutional review board of Krishnadevaraya College of Dental Science and Hospital, under the registration number of (ACA/DCD/SYN/KCODS - B/PG/2013-2014).

Inclusion Criteria:

• • Patients with a positive response for hypersensitivity testing (Pashley, 1990) i.e. cold water testing using ice cold water (Trowbridge et al., 1980),

  • Air blow test (Coleman and Kinderknecht, 2000),
  • Electric tactile stimulation test (Camps and Pashley, 2003),
  • Patients presenting with non-carious cervical lesions in the enamel (Loomba et al., 2013), fluorosed teeth wherein fluorotic enamel staining confirmed by clinical examination, healthy non fluorosed teeth, which was confirmed by clinical examination (Dean, 1934).

Exclusion Criteria:

• The following were set as the exclusion criteria;

  • Patients undergoing any form of restorative endodontic,
  • Orthodontic treatment or crown restorations,
  • Local defects including caries and fractures,
  • Presence of any systemic diseases,
  • Acute pain conditions (like apical periodontitis, periapical abscess),
  • Presence of periodontal disease or a history of periodontal treatment in last 6 months,
  • Usage of desensitising toothpaste or mouth rinse in the last 4 weeks,
  • Patients allergic to ingredients used in the study product,
  • Teeth with intrinsic stains caused by other reasons.

A unified stratified randomization, double blind controlled parallel designed was the type generated the allocation sequence. A skilled assistant enrolled the participants and assigned the participants to interventions.