trial will be done to evaluate the effect of archwire gauge on the rate of canine retraction, canine tip and torque, root resorption and loss of anchorage in maxillary dental protrusion cases requiring first premolars extraction.

Three working archwires of different gauges will be used during canine retraction; st.st 0.019×0.025" as a comparator, st.st 0.016×0.022" and st.st 0.017×0.025" wires as interventions. after levelling and alignment till reaching the working archwire, it will be left in place for a month then maxillary first premolars will be extracted and base line records will be taken(digital models, digital periapical radiographs and panorama). digital models will be taken monthly to measure rate of canine retraction for 6 months. after 6 month evaluation of anchorage loss, change in canine tip and torque will be done on last obtained digital model , panorama will be taken to evaluate the change in canine tip and digital periapical radiograph will be taken and compared with the preretraction radiograph to evaluate amount of root resorption.

Inclusion Criteria:

• Adult females (age range 18-28 years old).
• Maxillary dental protrusion indicating first premolars extraction.
• Full permanent dentition (not necessitating third molars).

Exclusion Criteria:

• Patients having systemic diseases or on medications that would affect tooth movement.
• Active periodontal disease or obvious bone resorption in maxillary arch.
• Patients with habits that are detrimental to dental occlusion (thumb sucking, tongue thrusting … etc.).
• Previous orthodontic treatment.
• Missing teeth.

adult female patients

The outcome assessor is not informed about the gauge of the wire used for patients