The Esthetic Evaluation Of Upper Lip Line’s Positions Of Posed Smile By Orthodontic Patients

Objective:With the development of the society and people’s aesthetic requirements, more and more malocclusion patient are seeking orthodontic treatment for a charming smile. Orthodontists should concern about not only the occlusion of the teeth, the harmonized side of the appearance, but also the dynamic beauty of the smile. Especially the relationship between the upper lips and the teeth, which influenced the aesthetics of smile, has attracted much attentions of the Orthodontists. In the mean time, the perception of patients’aesthetic is very subjective. There are many factors affecting the smile esthetics, such as age, gender, malocclusion classification, culture, and people’s experience and so on. All of them can affect the orthodontic treatment and the good relationship between doctors and patients. Therefore, the objective of this investigation is to evaluate the influence of the position of upper lips on the smile esthetics by orthodontic patients with different age, sex and malocclusion classification. Moreover, it also helps orthodontists to make a prediction about the orthodontic results, and to provide references for the co-evaluation between patients and doctors on the smile aesthetics.Methods:Choose 37 numbers of medical school graduate students in shandong university. All of them have been professionally indicated about how to get a posed smile, and then take pictures of their frontal posed smiles. All of the images of smiles are evaluated by 40 reviewers (10 orthodontic doctors,10 oral general practitioners and 10 orthodontic patients,10 patients’ parents) who indicate the level of attractiveness of each smile on visual analog scales (VAS), and finally picked out two pictures with average beauty posed smile, one for man, and one for woman. Two frontal intraoral photographs with ideally aligned teeth are selected from the patients after orthodontic treatments, one for man and one for woman. The two ideally aligned teeth and the two lips from the picture with average beauty posed smile are combined by using Adobe Photoshop CS2 (San Jose, CA) to form a standard composite smile, respectively. The combined pictures are also modified with the photoshop software by upping and lowing the upper lip’s position. A panel of 300 orthodontic patients, which are during orthodontic treatment, are selected randomly from stomatological hospital of shandong university as the evaluators. The ages are from eighteen to fifty. All of the evaluators are divide into different groups according to age, gender, and malocclusion classification. The data are used SPSS19.0 for statistical analysis.Results:(1)The three groups with different ages showed a significant difference in their aesthetic evaluation about the favorite upper lip positions in both male and female (P < 0.05). In the male groups, the three images which are most preferred by the young groups are M6, M5, and M7. The three images which are most preferred by the middle-young groups are M6, M7, and M8. The three images which are most preferred by the middle groups are M7, M8, and M6. On the other hand, in the female groups, the three images which are most preferred by the young groups are W5, W6, and W7. The three images which are most preferred by the middle-young groups are W6, W7, and W8. The three images which are most preferred by the middle groups are W7, W8, and W6.(2)The research showed that there are no significant difference in the preferences of upper lip positions in both the male or female images according to the valuator’ gender (P>0.05). In the male groups, the three images which are most preferred by the male groups are M7, M6, and M8. The three images which are most preferred by the female groups are M6, M7, and M5. In the female groups, the three images which are most preferred by the male groups are W7, W6, and W8. The three images which are most preferred by the female groups are W6, W7, and W5.(3)The three groups with different malocclusion classification show a significant difference in their aesthetic evaluation about the favorite upper lip positions in both male and female (P< 0.05). In the male groups, the three images which are most preferred by the group of class I malocclusion are M6, M7, and M5. The three images which are most preferred by the group of class II malocclusion are M7, M8, and M6. The three images which are most preferred by the group of class III malocclusion are M5, M6, and M7. On the other hand, in the female groups, the three images which are most preferred by the group of class I malocclusion are W6, W7, and W5. The three images which are most preferred by the group of class II malocclusion are W7, W8, and W6. The three images which are most preferred by the group of class Ⅲ malocclusion are W5, W6, and W7.Conclusions:1. Age can affect the esthetic evaluation of upper lip line’s positions of posed smile. The middle-aged patients and the young and middle-aged patients tend to prefer the lower upper lip lines, when compared to the young-aged patients. Which is accorded with the age-related changes of the posed smile. In clinical, orthodontic doctors should be pay more attention to the soft tissue changes in patients with different ages, as far as to make an individual treatment plan.2. There was no significant difference in evaluating the influence of the position of upper lips on the assessment of attractive smile esthetics by orthodontic patients with different sex.3. Malocclusion classification can affect aesthetic evaluation of upper lip line’s positions of posed smile. Patients with class II malocclusion tend to prefer the lower upper lip line, patients with class III malocclusion tend to prefer the higher upper lip line. Which is closely related to the smile characteristic with different malocclusion classification. In clinical, orthodontic doctors should be aware of the fact, and should be cautions with patients’ aesthetic expectation.