A Comparative Cephalometric Evaluation of Maxillary Central Incisor Crown Root Relationships in Various Malocclusions

Background and Objectives: An attractive smile is a pleasant effect of Orthodontic treatment which has got a lot of emotional benefits.The variation in tooth morphology of anteriors and its angulations and Inclinations play an important role in Smile Esthetics.The angulations of the root to the crown of a single rooted anterior teeth is known as Collum angle.The Collum angle of a single- rooted teeth is of particular interest to an Orthodontist because any variation in root angulations can cause unpredictable axial force application in movements such as intrusion and extrusion.The aim of the study is to compare the Collum angle,Labial crown root angle and Torque angle of class I with that of class II and class III.

Materials and Methods: Lateral cephalometric radiographs of 15 patients with age 20-30yrs, each for Class I,class II div 2,Class II div 1,Class III. patients were collected from the Department of Orthodontics, Azeezia College of dental science. Lateral cephalometric radiographs are scanned, digitized, and loaded into Nemoceph software for landmark identification and measurement.These measurements were compared to find the changes in CA,LCRA and torque angle of maxillary central incisors of patients with class I ,class II and class III dental malocclusion.

Results and Discussion: CA, LCRA, Torque angle of Class II div 2 shows significant difference when comparing with other classes of malocclusion. Variations in the crown-root angle, or "collum angle" (CA), is an important factor in treatment planning because it helps to achieve greater predictability in root position, and to anticipate difficulties with intrusion, extrusion, tipping and torqueing mechanics.

Conclusions: CA, LCRA, Torque angle of Class II div 2 malocclusion showed significantly greater value, when comparing with other classes of malocclusion.