Comparison of Maxillary Central Incisor Labial Crown-Root Angle with Collum Angle in Class I and Class II Division 2 Malocclusion.

ABSTRACT

To anticipate difficulties with intrusion, extrusion, or torqueing mechanics in certain malocclusions, a thorough understanding of crown-root relationships in the bucco-lingual plane is warranted. This study aimed at examining the collum angle of the maxillary central incisor in Angle’s class I and class II division 2 malocclusion and compare these values with the Labial Crown Root Angle (LCRA). MethodsThis study was conducted on two groups i.e., group 1 comprising of 26 Angle’s Class 1 subjects and group 2 comprising of 26 Class II div 2 subjects. Cephalometric measurements of collum angle and LCRA of maxillary central incisors were recorded for each subject and were compared between the two groups. ResultsThe mean Labial Crown-Root Angle was 28.35 ± 4.01 and 38.51 ± 5.80 for class I and class II division malocclusions respectively. Compared to the LCRA of Angle’s class I malocclusion, the mean LCRA of Angle’s class II division 2 was found to be greater, and is statistically significant. There was no significant gender variation. The mean difference between class I and class II div 2 malocclusion was found to be 9.42 ± 2.23 for collum angle and 10.16 ± 1.79 in LCRA respectively. ConclusionsThe Labial Crown Root Angle and collum angle of Angle’s Class II div 2 malocclusion were greater than the corresponding values in Angle’s Class I malocclusion. Also, the LCRA is a more simplified method for measuring the crown root angle and can be used as an adjunct to collum angle.