Comparison Change of Pre and Post-Treatment in Vermilion Height and Lip Area in Adult Class II Division I Malocclusion Treated with Premolar Extraction

Abstract

Aim: This study aimed to evaluate the alterations in vermilion height and lip area before and after fixed orthodontic treatment in adult patients with Class II Division I malocclusion who underwent premolar extractions. Assessments were conducted using frontal photographs and measurements from lateral cephalograms focusing on dentoalveolar and soft tissue parameters. Methods: Twenty-three adult patients with Class II skeletal malocclusion were selected from the records of the Department of Orthodontics and Dentofacial Orthopedics at AJ Institute of Dental Sciences, Mangalore. Pre-treatment and post-treatment lateral cephalograms and frontal photographs were obtained. Cephalograms were captured using a standardized KODAK 8000c digital cephalostat (69 kVp, 12 mA, 2 s), ensuring accurate patient positioning. The same investigator manually traced the cephalograms to minimize observer variability. Measurements were computed both manually and digitally for comparison purposes. Results: The study found a significant increase in the thickness from the cervical portion of the upper incisors to the upper lip after treatment (mean post-treatment: 15.77±2.28 mm; pre-treatment: 14.95±1.90 mm; P=0.006). Conversely, the thickness from the lower incisors to the upper lip decreased significantly post-treatment (mean post-treatment: 15.46±2.72 mm; pre-treatment: 17.26±2.19 mm; P<0.001). Additionally, there was a significant increase in vermilion height (St-Me) and lower facial height (N-Me) after treatment, with mean differences of 3.58 mm (P<0.001) and 1.18 mm (P=0.04), respectively. Conclusion: Orthodontic treatment involving premolar extractions in Class II Division I malocclusion patients led to significant soft tissue changes, particularly in lip thickness and vermilion height. Other parameters did not exhibit statistically significant differences.