Improvement Of Lip Line Canting By Orthodontic Camouflage Treatment

Objective: To study the improvement of lip line canting(LLC)by orthodontic camouflage treatment(OCT).Materials and Methods: 128 orthodontic patients aged from 16 to 35 were selected from a hospital,whose photos of the lip line at relaxed expression and at smiling expression before and after OCT were collected,with age and gender recorded.The degree and direction of the lip line were measured with the eye plane as reference plane so as to analyzed the improvement of lip line canting(LLC)by orthodontic camouflage treatment(OCT).Results: Individual normal occlusion was achieved in 128 orthodontic patients after OCT.The average degree of LLC before and after OCT was1.49° and 1.11°respectively in lip position at relaxed expression and the difference between the two groups was significant(p < 0.05).The average degree of LLC before and after OCT was 1.37° and1.128°respectively in lip position at smiling expression and the difference between the two groups was significant(p < 0.05).After the OCT,the LLC was significantly improved.The average degree of LLC after theOCT in the sensitive group(>2.65°)was significantly improved,which lowered from 3.62° to 1.43°.The average degree of LLC after the OCT in the several canting group(>4.1°)lowered from 4.56° to 2.0°.LLC was not associated with age or gender,nor with smiling or not.Conclusion:OCT can improve the LLC and the facial appearance by correcting the middle line of the dentition,improving the canting of the occlusal plane and removing the abnormal occlusal function.