The effect of 5 parameters on final torque values

Achieving ultimate orthodontic treatment goals requires full expression of torque . Variations in post-treatment torque values must be due to non-appliance related variables, The objectives of the study were: 1. To examine if ideal torque values were accomplished at the end of the treatment. 2. To evaluate potential factors which can affect final torque position: these include technique (labial vs lingual), treatment plan (extraction vs non-extraction), transverse expansion and curve of Spee (COS). Materials and Methods: 84 subjects who completed the orthodontic treatment were divided into: labial treated group (N=41) vs lingual treated group (N= 43), extraction group (N=38) vs non-extraction group (N=46), Cl I group (N=42) vs Cl II (N=42), curve of Spee (COS) and transverse dimension. Torque was measured with torque angle gauge and distances with digital caliper. Results: In comparison to ideal torque values, the present's study's results showed diversity (up to 90%). Similarity was found between the labial vs lingual techniques (86%) and Angle classification (75%). Upper canine torque was significantly (P=0.002) affected by transverse expansion, and COS did not affect torque. Conclusion: Four factors were found to affect final torque position in a declining order of: 1. Transverse expansion, 2. Angle classification (Class I vs Class II), 3. Technique ( Labial vs Lingual) and 4. Treatment plan (Extraction vs non-extraction).