Comparative study of soft tissue parameters reliability by digital and manual tracing method: A cephalometric study

Aim: To compare and evaluate soft tissue linear and angular measurements reliability between Digital and Manual Tracing method

Objectives: The objective of the study is to conclude that digital and manual tracing method for soft tissue measurements are reliable and comparable to each other

Materials & methods: Lateral Cephalograms of 35 patients who reported for Orthodontic Treatment irrespective of the type of malocclusion were taken. A total of 24 measurements were taken with 17 Linear Soft Tissue Measurements and 7 Angular Soft Tissue Measurements respectively. The digital images of each cephalogram was directly imported to Nemoceph Software for digital tracing whereas for manual tracing compatible printed images were used.

Results: Soft Tissue Chin Thickness, Lower Lip Thickness, A’- B’, Sn’-Pog’, Upper Lip Length, Upper Lip Protrusion, Upper Lip Anterior - Lower Lip Anterior showed statistically significant difference between the two techniques among linear measurements but were clinically acceptable (difference between the digital and manual technique were less than 2 units ie 1 unit = 1mm for linear measurement and 1 degree for angular measurements). Throat Length also showed statistically significant difference between the two techniques for linear measurement but was not clinically acceptable as it exceeded 2mm difference. Amongst the Angular measurement only Z-Angle Upper Lip showed statistically significant difference between the two techniques but was clinically acceptable.

Conclusion: Digital measurements were found to be reliable and comparable to manual tracing method for all soft tissue linear and angular measurements except Throat Length.