Methods used to evaluate “black spaces”

Abstract

We read the recent study reported by Pithon et al in the March 2013 issue of the AJO-DO.1Pithon M.M. Bastos G.W. Miranda N.S. Sampaio T. Ribeiro T.P. Nascimento L.E. et al.Esthetic perception of black spaces between maxillary central incisors by different age groups.Am J Orthod Dentofacial Orthop. 2013; 143: 371-375Abstract Full Text Full Text PDF PubMed Scopus (33) Google Scholar We sincerely congratulate the authors and appreciate their contributions. However, we have 2 major concerns about this study. First, the evaluators were required to complete questionnaires and score the images while the images were arranged in increasing or decreasing order of black spaces, but not in random order. This would guide the way of perceiving of the evaluators, who might note the black spaces and score according to the order of the images, but not exactly the size of the black spaces. This could impair the subjectivity of the concept of beauty of each evaluator as well as the objectivity of the results. If the image order were randomized, answers to whether they noted differences between the images might be different from results of this study.2Cao L. Zhang K. Bai D. Jing Y. Tian Y. Guo Y. Effect of maxillary incisor labiolingual inclination and anteroposterior position on smiling profile esthetics.Angle Orthod. 2011; 81: 121-129Crossref PubMed Scopus (60) Google Scholar, 3Pithon M.M. Santos A.M. Couto F.S. da Silva Coqueiro R. de Freitas L.M. de Souza R.A. et al.Perception of the esthetic impact of mandibular incisor extraction treatment on laypersons, dental professionals, and dental students.Angle Orthod. 2012; 82: 732-738Crossref PubMed Scopus (22) Google Scholar Scores and correlations between the 3 age groups might also be different. Another concern of ours is that different people have different perceptions of smile esthetics. The thresholds of different age groups perceiving the impact of black spaces on smiling esthetics are different. If the size of a black space were below the threshold, laypersons could hardly note it. There is an exaggerated concern by dental specialists rather than an esthetic need.4Pinho S. Ciriaco C. Faber J. Lenza M.A. Impact of dental asymmetries on the perception of smile esthetics.Am J Orthod Dentofacial Orthop. 2007; 132: 748-753Abstract Full Text Full Text PDF PubMed Scopus (131) Google Scholar Procedures with a view to correcting the black spaces might be justifiable when the differences in perception were fully discussed with the patient, especially an adult, because the treatment should respect the patient's wishes. Esthetic perception of black spaces between maxillary central incisors by different age groupsAmerican Journal of Orthodontics and Dentofacial OrthopedicsVol. 143Issue 3PreviewThe aim of this research was to evaluate esthetic perceptions of the smile, especially regarding black spaces between the maxillary central incisors, by laypersons in 3 age groups. Full-Text PDF Author's responseAmerican Journal of Orthodontics and Dentofacial OrthopedicsVol. 143Issue 6PreviewI would like to thank Drs Guo and Bai for their interest in our article. Their comments were pertinent. I want to explain something that was not clear in our manuscript. Initially, the miniatures of all the images were mounted on a page, starting with the image of the smallest black space and progressing toward the largest black space. On another page, the same images were mounted, but this time starting with the largest black space and progressing to the smallest black space. These 2 initial pages served only to verify whether the evaluators knew how to distinguish 1 image from the other. Full-Text PDF