Fluoride Varnishes

This randomized controlled clinical trial aims to determine whether different fluoride varnish formulations reduce dentin hypersensitivity (DH) in young adults diagnosed with DH. The primary purpose of this study is to evaluate the clinical effectiveness of two commercially available fluoride varnishes. The main questions this study aims to answer are: * Does Clinpro Clear® (aqueous base, 9,500 ppm NaF) lead to a greater reduction in dentin hypersensitivity compared with Duraphat® (rosin/resin base, 22,600 ppm NaF)? * Do these varnish formulations improve oral health-related quality of life and patient satisfaction? Researchers will compare a single application of Duraphat® with a single application of Clinpro Clear® to assess differences in hypersensitivity reduction, quality-of-life outcomes, and patient satisfaction. Participants will: * Receive one application of either Duraphat® or Clinpro Clear® under standardized clinical conditions. * Complete baseline and post-treatment evaluations, including: * Dentin hypersensitivity intensity using a visual analogue scale (VAS) * Air-blast response using the Schiff scale * Oral health-related quality of life using the OHIP-14 * Patient satisfaction using the CSAT survey

In this study the investigators aimed to explore the antibiofilm effect of fluoride varnish loaded with titania nanoparticles synthesized from moringa oleifera leaves extract vs conventional fluoride varnish in multibracket fixed orthodontic patients.