An Experimental Study on Esthetic Preference and Satisfaction of Lip Position with Various Facial Divergences among the South Indian Population.

Aim: The aim of this study was to establish the most and least pleasing lip position and to evaluate esthetic preference in profile view among the South Indian population with diverse facial divergence. Materials and
Methods: Photographs of 12 participants with an average lip position were taken, and original lip position (Image C) was altered by ± 2 mm and ± 4 mm from the original position of upper and lower lips using Adobe Photoshop 7.0 version. Image A and Image B comprised photographs with retrusive lips of 4 mm and 2 mm, respectively, and Image D and Image E comprised photographs with protrusive lips of 2 mm and 4 mm, respectively. The altered photographs were evaluated for pleasing lip positions by 300 examiners which comprised 102 orthodontists, 107 general dentists, and 91 laypersons.
Results: A questionnaire was conducted through Google Forms, and the examiners favored Image C with an average lip position as the most desired lip position, whereas Image E with 4-mm lip protrusion and Image A with 4-mm lip retrusion were the least desired irrespective of gender or facial divergence.
Conclusion: Importance to establish appropriate soft-tissue esthetics is the primary concern of an orthodontic treatment. Copyright:

INTRODUCTION

Soft-tissue examination, according to Burstone, is a key aspect in appropriate orthodontic treatment planning. Facial esthetics in profile view must be given more importance since interrelationship between the five facial prominences is considered as facial form.[1] Lip posture in overall facial esthetics, posttreatment stability, and function is a significant factor.[23] According to Steiner, to determine the soft-tissue facial equilibrium, lips should touch the S-line.[4] To examine the lip location, Ricketts described the E-plane (Esthetic plane).[5] In adults, the lower lip should be 4-mm posterior to the E-plane, whereas in children, the lips should be slightly full and 2-mm posterior to the E-plane.[6] The typical upper lip prominence is 3 ± 1 mm, whereas the lower lip is 2 ± 1 mm anterior to the Sn-Pog' line, according to Legan and Burstone. Bell et al. used a vertical reference plane and said that the upper lip should be 1–2 mm ahead of this line, whereas the lower lip should be on or 1 mm behind the line.[7] According to Reed Holdaway, lower lip's prominence in relation to the H-line (Harmony line) if the lips are positioned beyond they are protrusive, and if they are placed behind, they are retrusive. In both cases, orthodontic treatment is required to rectify the lip position. According to C. C. Steiner, a line connecting the midpoint of the columella of the nose to the soft-tissue pogonion is the S-line (Esthetic plane of Steiner) and the lips should fall on this line.[8]

The goal of this study is to determine the esthetic choice and satisfaction with lip position among South Indians with distinctive facial divergence.

MATERIALS AND METHODS

A total of 12 South Indian subjects (six males and six females) aged between 13 and 25 years with an average lip position based on E-line and S-line were chosen. Subjects with competent lips, all permanent teeth erupted were included while patients with previous orthodontic treatment history, as well as those with syndromes, facial damage, or congenital anomalies, were excluded from the study. The participants were divided into three groups based on their facial divergence: straight, anterior, and posterior divergence. There were two males and females in each divergence. For each person, a right profile view photograph was taken in their natural head position with their lips relaxed. Each individual's picture is altered in which the Image C is the average lip position, Image A at −4 mm most retrusive lip, Image B at −2 mm retrusive lip, Image D at +2 mm protrusive lip, and Image E at +4 mm most protrusive lip were created by altering the position of upper and lower lips by 2 mm and 4 mm beyond and behind the initial location of upper and lower lips in Image C using Adobe Photoshop 7.0 version [Figures 1-3].

Figure 1

Straight divergent male. (a) 4 mm retrusive lip, (b) 2mm retrusive lip, (c) Original lip position, (d) +2 mm protrusive lip, (e) +4 mm protrusive lip

Figure 3

Anterior divergent female. (a) 4 mm retrusive lip, (b) 2mm retrusive lip, (c) Original lip position, (d) +2 mm protrusive lip, (e) +4 mm protrusive lip

Posterior divergent male. (a) 4 mm retrusive lip, (b) 2mm retrusive lip, (c) Original lip position, (d) +2 mm protrusive lip, (e) +4 mm protrusive lip

Each individual had five images posted to Google Forms. A total of 300 assessors, including 102 orthodontists, 107 dentists, and 91 laypersons, took part in the study to choose the most appealing and least attractive lip position in the profile view using a Google Forms Questionnaire.

RESULTS

Among straight divergent males, orthodontists (71.6%), dentists (58.4%), and laymen (51.1%) preferred Image C. Orthodontists (17.6%) and dentists (23.4%) preferred Image B whereas laymen preferred Image D (14.3%). Least preferred lip position was Image E with 4-mm lip protrusion by orthodontists (74.5%), dentists (68.7%), and laymen (62.1%) followed by Image A with 4-mm lip retrusion. Among straight divergent females, Image C with average lip position was the most preferred lip position by orthodontists (79.9%), dentists (63.6%), and laymen (47.8%), followed by Image B by orthodontists (14.7%) and dentists (17.7%), whereas laymen preferred Image B (19.8%) and D (19.2%) equally. Image E with 4-mm lip protrusion was the least preferred lip position by orthodontists (78.5%), dentists (63.6%), and laymen (65.9%) followed by Image A with 4-mm lip retrusion. In straight divergent males and females, dental experts preferred 2-mm lip retrusion over 2-mm lip protrusion. Image C with average lip position was the most preferred lip position by orthodontists (69.9%), dentists (70.6%), and laymen (56%), followed by Image B by orthodontists (17.2%), dentists (14.0%), and laymen (19.8%), and Image E with 4-mm lip protrusion by orthodontists (73.0%), dentists (63.6%), and laypersons (67.6%) was the least preferred lip position among posterior divergent male.

Orthodontists (68.6%), dentists (60.7%), and laymen (46.1%) chose Picture C with an average lip position, followed by Image B dentists (15.9%) and laymen (26.9%), whereas orthodontists preferred Image D with a lower lip position (16.2%). Image E with 4-mm lip protrusion was the least desired lip position by orthodontists (53.9%), dentists (56.5%), and laymen (61%) among posterior divergent females, followed by Image A with 4-mm lip retrusion.

Orthodontists (74%), dentists (61.2%), and laypeople (52.8%) chose Image C with an average lip position, followed by Image B orthodontists (15.7%) and laypeople (30.3%), whereas dentists preferred Image D.(20.2%). Image E with 4-mm lip protrusion was the least desired lip position among anterior divergent males by orthodontists (74%), dentists (62.6%), and laypeople (63.7%), followed by Image A with 4-mm lip retrusion.

Orthodontists (79.4%), dentists (61.2%), and laypeople (48.9%) chose Picture C with average lip position, followed by Image B orthodontists (16.7%), dentists (21.0%), and laypeople (29.7%). Picture E with 4-mm lip protrusion was the least desired lip position among anterior divergent females by orthodontists (73.5%), dentists (53.3%), and laypeople (71.4%), followed by Image A with 4-mm lip retrusion.

The results of the Google Forms survey were tallied, and statistical analysis was performed with IBM's Statistical Package for Social Sciences (SPSS) Version 20 (IBM, Chicago, Illinois, USA). Using the Chi-square test, male and female subjects were compared in straight, posterior, and anterior divergences. No significant difference between male and female perception was found [Table 1].

Table 1

Comparison of proportion of perceptions of orthodontists, dentists, and others

Variables	χ 2	Df	P
Straight
Attractive male	66.715	8	0.000*
Least attractive male	29.987	8	0.000*
Attractive female	61.870	8	0.000*
Least attractive female	37.529	8	0.000*
Posterior
Attractive male	27.271	8	0.001*
Least attractive male	33.338	8	0.000*
Attractive female	36.747	8	0.000*
Least attractive female	19.944	8	0.011*
Anterior
Attractive male	23.927	8	0.002*
Least attractive male	22.814	8	0.004*
Attractive female	57.749	8	0.000*
Least attractive female	40.465	8	0.000*

*Significant at P<0.05 level, Chi-square test

DISCUSSION

It is critical to comprehend how orthodontic therapy affects the appearance of the soft tissues, specifically the lip position.[9] Forsberg in his study found that with increasing age, the upper lip grew more retrusive than the lower lip.[5] Prominence of the chin and lips was found to influence facial attractiveness, according to Modarai.[10] Evrard came to the conclusion that the soft-tissue profile had a greater influence on the decision of extraction.[11] Shimomura found that in Japanese orthodontic patients, a slightly retruded lip position was favored, which is similar to the findings of this study.[12]

The current study included 12 people aged 13–25-year-old, six males and six females, with two males and two females chosen from straight, posterior, and anterior facial divergences. Image C refers to subjects who have an average lip position.

Image A at −4 mm, Image B at −2 mm, Image D at +2 mm, and Image E at +4 mm were created by altering the location of upper and lower lips in Adobe Photoshop 7.0 version by 2 mm and 4 mm beyond and behind the initial position of upper and lower lips in Image C. To analyze the cosmetic lip position, 300 examiners, including 102 orthodontists, 107 dentists, and 91 laypeople, analyzed the photos. In straight, anterior, and posterior divergences, Image C with average lip position was regarded the most preferred lip position, and Image E with +4 mm lip protrusion was considered the least preferred lip position among orthodontists, dentists, and laypeople, which is comparable to the study done by Zarif Najafi et al.[13]

Image C was the most desired lip position in posterior divergent males, followed by Image B and Image D in all groups. All of the groups found Image E with 4-mm lip protrusion to be the least appealing, followed by Image A with 4-mm lip retrusion. Image C with average lip position was the most beautiful in posterior divergent females, followed by Image D with 2-mm lip protrusion and Image B with 2-mm lip retrusion, which corresponded with Lines et al.'s study. Dentists liked 2-mm lip protrusion, whereas orthodontists and laypeople preferred 2-mm lip retrusion. Image E, which has a 4-mm lip protrusion, was deemed the least appealing, whereas Image A, which has a 4-mm lip retrusion, was deemed unappealing.

Image E (followed by Image A) was shown to be the least appealing lip position in anterior divergent males and females in all three groups, which is consistent with the findings of Zarif Najafi et al.[13] The most appealing lip position was Image C, followed by Image B.

CONCLUSION

Image C, Image B, and Image D are the most appealing lip positions, with Image C having a substantially higher preference than Image B, which has an average lip position according to the E- and S-lines. The least appealing lip positions were Image E and Image A, whereas Image E received the least preference.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initial s will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.