Emoji as promising tools for emotional evaluation in orthodontics

Background: Emoji are pictograms frequently used in social networks capable of expressing emotions. These tools can provide insights into people's behavior that could not be obtained with the use of textual communication. Recently, emoji have been introduced to various research fields as successful alternatives to word-based questionnaires for measure emotional responses. The objective of this study was to preliminarily evaluate the discriminating ability and relationship of these tools with different occlusal conditions/malocclusions.

Methods: Online surveys were applied to adult individuals (n = 201; mean age = 27.4 ± 5.7; 37.3% males, 62.7% females). Subjects issued acceptance scores (10-point scale) and expressed their emotional status using a 30-emoji list in relation to nine occlusal conditions: C1-crowding, C2-anterior open bite, C3-interincisal diastema, C4-increased overjet + deep bite (Class II div. 1), C5-anterior crossbite (Class III), C6-ideal occlusion, C7-unilateral posterior crossbite, C8-anterior open bite plus bilateral posterior crossbite plus crowding, and C9-deep bite (Class II div. 2). Cochran's Q and McNemar tests were used to compare the frequencies of choice of emoji between conditions. Correspondence analyses were applied to assess the association between occlusal conditions and emoji. Kendall's correlation coefficient was calculated to evaluate the relationship between mean acceptance scores and frequency counts of each emoji.

Results: The frequency of choice between conditions showed a significant difference for 25 of the 30 emoji (P < 0.05), indicating an adequate discriminating ability of these tools. Emoji were grouped predominantly based on their emotional valence (positive/negative) and arousal/activation (high/low). Positive emoji were associated with the most accepted conditions (i.e., C6, C3), while negative emoji with the most rejected ones (i.e., C8, C1, C2). Although only weak, positive correlations between acceptance and positively valenced emoji, and negative correlations between acceptance and negatively valenced emoji were observed (P < 0.05).

Conclusions: Emoji have an adequate discriminatory ability and would allow determining emotional profiles in the face of different occlusal conditions. Further research is necessary to consolidate the use of these tools in an instrument that allows measuring emotional responses.