To evaluate and compare the clinical effectiveness of a Bioactive Desensitizer Gel (which releases calcium and phosphate to form hydroxyapatite) versus a standard 5% Sodium Fluoride (NaF) Varnish in reducing cervical dentin hypersensitivity (CDH) in adult patients over a period of 6 months.

Inclusion Criteria:

• • With ≥1 sensitive tooth and with exposed dentin in the upper or lower dental arches.

  • Grade IV gingival recession.
  • Schiff sensitivity score needed to be ≥2, indicating that application of a jet of air makes the patient respond and move or requests discontinuation of the stimuli application.

Exclusion Criteria:

• • Domestic or in-office fluoride application and bleaching 6 months before beginning of treatment

  • Long-term use of anti-inflammatory, analgesic and psychotropic drugs.
  • Allergies to product ingredients
  • Eating disorders, systemic conditions that cause or predispose patients to develop dentin hypersensitivity (for example, gastroesophageal reflux disease, GERD)
  • Excessive dietary or environmental exposure to acids.
  • Orthodontic appliance treatment within the previous three months.
  • Periodontal surgery within the previous three months before the study