Inclusion Criteria:  Angle´s Class II canine relationship, at least half-unit. Skeletal Class I or mild Class II relationship. Upper second molars were fully erupted before starting distalization. Normal or horizontal growth pattern. Good oral hygiene. Absence of any systemic diseases  Exclusion Criteria:  Previous orthodontic treatment. 2. Patients who required surgery to correct skeletal discrepancies (sever skeletal class11).  3. Patients with hyperdontia, hypodontia, or syndromic diseases. 4. Extraction or badly destructed teeth in upper arch  -