Tip and Torque Angle of Permanent Teeth: A Comparison Between Treated Patients and Normal Group

• Main Authors: Amir Farhang Miresmaeili, Nasrin Farhadian
• Format: Article
• Language: fas
• Published: Hamadan University of Medical Sciences 2005-03-01
• Series: پزشکی بالینی ابن سینا
• Subjects: occlusion; orthodontics; tooth inclination; tooth movement
• Online Access: http://sjh.umsha.ac.ir/article-1-585-en.html

The angle of long axis of tooth crown is called tip in mesiodostal and torque in faciolingual direction. Both have special importance for producing an ideal occlusion. The aim of the present study was determination of the average tip and torque of each permanent tooth in well treated patients with edgewise system compare to control group with normal occlusion. In this study, 19 well treated cases through standard edgewise technique with non extraction strategy and 20 students of pre-university schools with normal occlusion according to IOTN were selected. Reference points and lines were marked on facial surface of each tooth on casts. Special device was designed for measuring the faciolingual and mesiodistal inclination of crowns. After 3 times measuring the tip and torque of teeth, student t-test and Kruskal – Wallis analysis were used for statistical analysis. The mean age of control group was 18.8 ± 0.5 year and in treated group was 20.3 ± 0.8. There was significant difference between mean of torque in control group and treated group for upper lateral incisor (4.75±5.21 , 8.76±5.82 respectively , p<0.03 ) . Also a significant difference was seen in average torque of lower second premolar between control group and treated one ( -23.48±5.99 , -26.66±4.64 respectively , p<0.05).    There were no significant differences in tip of teeth between two groups. In comparison with Andrews study, in normal occlusion group, upper canine & first molar and lower lateral & first premolar had more buccal root torque.  Except the torque of upper lateral incisor and lower 2nd premolar,    torque and tip of other teeth had no significant difference.