Attractiveness ratings of anterior open bites and reverse overjets using the aesthetic component of the Index of Orthodontic Treatment Need.

This study was carried out to determine the level of attractiveness of anterior open bites (AOB) and reverse overjets of varying severity. A sample of 180 non-dental students (101 females and 79 males; average age 20 +/- 0.75 years) and 45 dental professionals (12 females and 33 males; average age 35.5 +/- 5.07 years) was asked to complete a questionnaire to rate the level of attractiveness of AOB and reverse overjets of varying severity using the aesthetic component (AC) of the Index of Orthodontic Treatment Need (IOTN). Photographs of mild and severe AOB and reverse overjets were projected onto a white screen in a lecture theatre (15 seconds each with a 5 second interval between images). The participants were asked to record the AC grade at which they thought the projected picture of the AOB or reverse overjets had similar attractiveness. Dental awareness of non-dental students was determined by asking them their opinion on how important it was to have straight teeth (very unimportant, unimportant, important, very important), about their personal or close family members' orthodontic experiences and if they thought they were in need of any orthodontic treatment. A chi-square test was applied to record any differences between sexes and between the different groups. Backward stepwise linear regression analysis was used to determine the relationship between the students' ratings of the photographs and their dental awareness. The majority of non-dental students rated a mild AOB (93 per cent) and mild reverse overjet (96 per cent) to be aesthetically acceptable. A mild AOB and mild reverse overjet were found to be acceptable by 40 and 58 per cent of dental professionals, respectively. The differences in the ratings between dental professionals and non-dental students were significant at P < 0.001.A severe AOB was considered unattractive by both students and dental professionals. However, dental professionals rated it at the more unattractive end of the scale (P < 0.001). A severe reverse overjet was rated by the majority of the subjects as aesthetically unacceptable (85 per cent of the non-dental students and 78 per cent of the dental professionals).