This study evaluates the profile changes and torque control using lingual lever arm vs conventional lingual mechanics. Half of the patients will receive lever arms and the other half will receive conventional lingual orthodontics.

Conventional lingual orthodontic biomechanics leads to torque loss during en masse retraction of the anterior segment in the bimaxillary proclination cases treated by first premolar extraction. Torque loss affects the final outcome of the treatment negatively.

Adding a lever arm to the lingual wire will transmit the point of force application at or apical to the center of rotation which will reduce or eliminate toqrue loss during anterior segment retraction.

Inclusion Criteria:

• Male or female adult patients with age range 18-30 yrs old.
• Class I bimaxillary dentoalveolar proclination.
• Full permanent dentition.
• Good oral hygiene.
• Maximum anchorage is required.
• Healthy bone around the first molars is needed.

Exclusion Criteria:

.Systemic disease.

• Severe crowding.
• Extracted or missing upper permanent tooth/teeth (except for third molars).
• Signs, symptoms or previous history of temporomandibular disorders (TMD).
• Previous orthodontic treatment.