Assessment of Vertical Anterior Teeth Display and Lip Position at Smiling

Abstract

Abstract:

Background: Smile aesthetics are influenced by the harmonious relationship between the maxillary anterior teeth, gingiva, lips and surrounding facial structures. Vertical anterior teeth display and upper lip position during smiling are important parameters in orthodontic diagnosis and aesthetic dental treatment planning. The present study aimed to assess vertical anterior teeth display and evaluate upper lip position during smiling among healthy adults. Materials and Methods: The present observational cross-sectional study included 40 healthy adult subjects aged 18–35 years. Demographic characteristics, including age and gender, were recorded. Standardized extraoral photographs were obtained at rest and during maximum posed smiling. Maxillary anterior teeth display, upper lip length, upper lip elevation, gingival exposure and interlabial gap were measured using calibrated image analysis software. Smile line patterns were categorized as high, average and low. The collected data were analysed using appropriate descriptive and inferential statistical methods. Results: Among the 40 participants, 18 (45%) belonged to the 18–25 years age group, while 14 (35%) and 8 (20%) belonged to the 26–30 and 31–35 years age groups, respectively. Equal gender distribution was observed. The mean upper lip length at rest was 21.45 ± 2.18 mm, while maxillary central incisor display at rest was 2.65 ± 1.12 mm. The mean maxillary anterior teeth display during smiling was 9.24 ± 1.46 mm, with an average upper lip elevation of 6.82 ± 1.35 mm. Mean gingival display and interlabial gap during smiling were 1.38 ± 1.21 mm and 12.65 ± 2.14 mm, respectively. The average smile line was the most prevalent pattern, observed in 22 (55%) participants, followed by low smile line in 10 (25%) and high smile line in 8 (20%) participants.Gender-wise comparison demonstrated significantly greater maxillary central incisor display at rest, anterior teeth display during smiling, upper lip elevation and gingival exposure among females compared with males. Conclusion: The study demonstrated variations in vertical anterior teeth display and upper lip position during smiling, with the average smile line being the most frequently observed pattern. Evaluation of these parameters may contribute to improved aesthetic assessment and individualized orthodontic and prosthodontic treatment planning.