Three-Dimensional Bolton–Brush Growth Study Landmark Data: Ontogeny and Sexual Dimorphism of the Bolton Standards Cohort

Abstract

Objective The treatment of craniofacial reconstructive surgery patients may benefit from comparison to average referent three-dimensional landmark data. These data may be useful for diagnosis, treatment planning, prosthetic design, or outcomes assessment. With regard to subadult patients, we hypothesize that the pattern of ontogenetic shape change of same sex, same ethnicity, referent populations will show gross uniformity. We present a preliminary shape analysis of 50 three-dimensional landmarks derived from 317 Bolton–Brush Growth Study biorthogonal image pairs. We determine which landmarks can be collected from scanned radiographs reliably by four operators for the precisely locatable points, ontogenetic trends in landmark configuration shape change, and patterns of sexual dimorphism. Participants Participants were Bolton standards individuals (16 male and 16 female) who contributed biplane cephalograms seven or more times with annual or greater spacing between ages 3 and 18 years. Design After removing outliers, we searched for ontogenetic heterogeneity, including sexual dimorphism and within sex-specific Procrustes coordinate shape spaces. Results A cut-off of 4.3-mm interoperator error left 32 landmarks in our analysis. Three different approaches (principal component analysis, age-trend analysis, and principal components of age residuals) all found no patterns of individual variation around sex-specific average trends of shape change. Male shape change peaks at age 15, a correlate of the growth spurt. Conclusions Simultaneous frontal and lateral anatomic landmark identification improves three-dimensional localization reliability. Three-dimensional craniodental shape change from ages 8 to 18 within the Bolton standards presents little heterogeneity. Considerations of ethnicity aside, these may be initial grounds for use of these data as a normative referent.

Proportional Growth of Craniofacial Regions

“…Mean outlines were available for each age group from 1 to 18 years. 3D-landmark analysis has recently shown that the Bolton standards provide a stable reference population with little heterogeneity [12].…”

“…Lebensjahr vorhanden. Eine kürzlich durchgeführte 3-D-Analyse ergab, dass mit den Bolton-Standards eine zuverlässige Referenzgruppe mit nur geringer Heterogenität zur Verfügung steht [12].…”

Ortodonti̇de Üç Boyutlu Görüntüleme Si̇stemleri̇: Li̇teratür Derlemesi̇

“…Bilgisayar programları o tarihten itibaren dijital sefalogram görüntülerinden doğrudan doğruya üç boyutlu koordinatları toplamak için geliştirilmiş, elle izleme ve fare tabanlı X-Y sayısallaştırma tabletlerine olan ihtiyacı ortadan kaldırmıştır. 3,4 Stereofotogrametri yöntemi, fotoğrafı çekilen objenin daha detaylı olmasını sağlamak için eski fotogrametrik tekniklerden geliştirilmiştir. Bu teknik, herhangi bir perspektiften izlenebilen ve herhangi bir yönden ölçülebilen bir üç boyutlu model oluşturmak için, bir veya daha fazla birleşen görüntü çiftini kullanır.…”

Dimorphisme sexuel et cavités faciales : étude volumétrique en imagerie 3D

“…Aussi, plusieurs études ont été menées en 3D dans différents domaines, par Hennessy et Moss [18], et Kau et Richmond [21], sur la croissance cranio-faciale, Nabbout, et al [24] sur les volumes des dents, Sampeur et Boileau [25] sur les muscles masticateurs ainsi que Dah-Jouonzo, et al [3,4] sur les mesures volumétriques des bases osseuses et des cavités aériennes de la face. D'autres auteurs, Kau, et al [22,23], Dean, et al [5], Ferrario, et al [11][12][13], ainsi que Sforza, et al [26], ont essayé d'étudier les structures osseuses, les tissus mous ou même la morphologie faciale en s'aidant d'outils capables de fournir des résultats en 3D. Mais l'aspect volumétrique du dimorphisme sexuel n'a pas encore été abordé, bien que les études en 2D aient trouvé une différence en taille, direction de croissance et pic de maturation entre les deux sexes [1,15,33].…”