A method for three-projection infant cephalometry.

OBJECTIVE To assess morphology and growth in infants and children with craniofacial anomalies based on comprehensive digitization of radiographic films in three, mutually orthogonal projections. METHOD The method consists of (1) acquisition of radiographic films in a highly standardized three-projection (lateral, frontal, and axial) cephalometer, (2) marking and digitization of a total of 279 anatomical landmarks in the three projections, and (3) computation and presentation (tabular and graphical) of 356 linear and angular variables describing the craniofacial morphology, including soft tissue. Computation of statistical entities describing a patient, a group of patients, the differences between patients or groups of patients was carried out. Error assessment of the method involved investigation of error distribution among a number of error sources. Duplicate digitization of radiographic films from 30 randomly selected patients, and from 10 dry skulls, was carried out to determine the errors contributed by the procedure of landmark digitization and the distribution of error among landmarks and variables, as well as between projections. RESULTS The average error due to landmark digitization, s(i), determined by duplicate digitization and calculated by use of Dahlberg's formula was 0.8 mm for linear variables and 1.6 degrees for angular variables. CONCLUSION This method of infant cephalometry has been shown to be highly accurate and reproducible, and it adds significant new potential for, e.g., asymmetry detection, population comparison, and growth measurements compared to other cephalometric techniques due to its standardized acquisition and digitization protocol, inclusion of an axial projection, and the large number of well-defined landmarks and variables involved.

[1]  A. Abbott,et al.  Computer-assisted location of reference points in three dimensions for radiographic cephalometry. , 1989, American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics.

[2]  H. Aduss.  Craniofacial growth in complete unilateral cleft lip and palate. , 1971, The Angle orthodontist.

[3]  W J Houston,et al.  The analysis of errors in orthodontic measurements. , 1983, American journal of orthodontics.

[4]  S. Pruzansky,et al.  Cephalometric roentgenography of infants: Sedation, instrumentation, and research , 1958 .

[5]  J. Nie,et al.  Highly cross-linked networks for dental applications obtained by photocuring of tris[2-(acryloyloxy)ethyl]isocyanurate, 2-ethyl-2-(hydroxymethyl)-1,3-propanediol triacrylate, and pentaerythritol triacrylate. , 1999, Acta odontologica Scandinavica.

[6]  A. Björk,et al.  Normal and abnormal growth of the mandible. A synthesis of longitudinal cephalometric implant studies over a period of 25 years. , 1983, European journal of orthodontics.

[7]  S. Kreiborg,et al.  A comparison of the craniofacial morphology in 2-month-old unoperated infants with unilateral complete cleft lip and palate, and unilateral incomplete cleft lip. , 1999, Journal of craniofacial genetics and developmental biology.

[8]  W. Houston,et al.  A preliminary study of facial growth and morphology in unoperated male unilateral cleft lip and palate subjects over 13 years of age. , 1990, The Cleft palate journal.

[9]  Z. Davidovitch,et al.  Glucocorticoid inhibition of cyclic AMP in the developing secondary palate. , 1981, Journal of craniofacial genetics and developmental biology.

[10]  E. Dahl.  Craniofacial morphology in congenital clefts of the lip and palate. An x-ray cephalometric study of young adult males. , 1971, Acta odontologica Scandinavica.

[11]  S. Kreiborg,et al.  A unit for infant roentgencephalometry. , 1977, Dento maxillo facial radiology.

[12]  S. Kreiborg,et al.  Cleft lip and palate in Denmark, 1976-1981: epidemiology, variability, and early somatic development. , 1988, The Cleft palate journal.

[13]  Timothy F. Cootes,et al.  Active Shape Models-Their Training and Application , 1995, Comput. Vis. Image Underst..

[14]  S. Kreiborg,et al.  Craniofacial growth in subjects with unilateral complete cleft lip and palate, and unilateral incomplete cleft lip, from 2 to 22 months of age. , 1999, Journal of craniofacial genetics and developmental biology.

[15]  A. Björk.  The use of metallic implants in the study of facial growth in children: method and application. , 1968, American journal of physical anthropology.