Smile Aesthetics in relation to bracket choice

Aim: The aesthetics of the frontal view of a smile are of serious importance to the final outcome of an orthodontic treatment. In a first part of this study the aims are to explore if there is conformity between eight different orthodontists concerning the type of bracket choice, where to find potential differences and lastly if cephalometric radiographs are needed for treatment planning.
Materials and methods: Eight experienced orthodontists (six females and two males) reviewed 50 casts (mean age 20.62 years; 36% male, 64% female) on the placement of brackets, on central upper incisors, with different types of torque (high 'H', standard 'S' or low 'L') without knowledge of radiographic data. The study examines whether there were similarities between the orthodontists. Combinations of four choices are obtained. Following combinations 'HHHH', 'SSSS', 'LLLL', 'HSSH', 'HSSS' and 'SHHH' are given a score of 0 and 'SSSL' got score -1. 'SSLL', 'HSSL' and 'SLHH' are given a score -2 and 'HHLL', 'SLLL', 'HLLL' and 'LHHH' got score -3. The null hypothesis states that there is no agreement between the observers in the type of bracket they choose.
Results: Tooth number 11 exhibits a strong correlation, corresponding to score 0, between the different practitioners in 82.0% of the ratings. Score -2 (weak correlation) occurs in 14.0% and score -3 (very weak correlation) in 4.0% of the ratings. 86.0% of the ratings of tooth number 21 exhibit strong correlation (score 0). 10.0% of the ratings exhibit score -2 and 4.0% corresponds to score -3.
Conclusion: There is some evidence to reject the null hypothesis. The results show, for both central upper incisors, great similarity concerning the choice of type of bracket between the eight orthodontists. Differences are often found in cases where one or more observers opt for low torque. This could imply that one may need to reflect well before placing this type of bracket. However there is an agreement for bracket choice at the central incisors in 82.0% without using cephalometric analysis in the treatment planning. This questions the use of cephalometrics for experienced orthodontists.