The goal of modern dentistry is to manage non-cavitated caries lesions non- invasively through re-mineralization process to prevent the disease progression and improve aesthetics, strength, and function. Re-mineralization is defined as the process that supplies calcium, phosphate and flouride ions from an external source to the tooth to convert ion deposition into crystal voids in demineralized enamel. White spot lesions should be managed using a multifactorial approach. The most important strategy is to prevent demineralization and biofilm formationand use of methodologies for remineralization of lesions .

Self-assembling peptide (P11-4) has shown great potential for natural repair of early caries lesions through emerging biomimetic re-mineralization properties. (Takahashi Fet al in 2015) This peptide forms a 3D matrix within demineralized carious lesions areas, which enables novo hydroxyapatite crystal formation facilitating the so-called guided enamel regeneration of the lost enamel structure. The peptide has shown encouraging results as a scaffold for enamel regeneration

Inclusion Criteria:

• Between the ages of 18 and 35 years of age female and males
• Had received conventional periodontal therapy
• Active carious white spot lesions
• No systemic diseases or concomitant medication affecting salivary flow

Exclusion Criteria:

• - Participant in another trial
• Non carious lesion (enamel hypoplasia and dental flourosis)
• Presence of abnormal oral, medical, or mental condition.
• Participants who had evidence of reduced salivary flow or significant tooth wear.
• Allergy to MI paste