Biomedical subjects
Publications and source records attributed to A S Ligthelm-Bakker.
Growth of the lips, nose and chin was studied in a mixed longitudinal sample of 82 subjects from the "Nijmegen Growth Study". The age range was between 9 and 14 years with a single measurement at the age of 22 years. Differences in growth pattern between boys and girls are illustrated by mean cumulative growth curves and mean growth velocity curves as well as by contour plots.
The mechanism of anterior vertical facial growth was studied in normal subjects between 7 and 22 years of age. This subsample (n = 60) of participants in the Nijmegen Growth Study was representative of normal variation with respect to vertical facial proportions. A negative correlation was found between the average growth rate of the upper and lower anterior facial height in boys. Boys with a relatively large facial height exhibited a higher than average growth rate of the lower anterior facial height compared with the upper facial height. In girls a similar trend was present. The individual average growth rate of the anterior upper and lower facial height maintains or accentuates the early established facial form.
Clinical examination of human profiles provides some idea of the localization of hard tissue landmarks, but is unreliable because of large variability in thickness of the soft tissues. In this investigation an instrument was developed to measure the thickness of the lips. Linear regression was applied to estimate cephalometric hard tissue landmarks from those in the soft tissues. By adding information from direct clinical measurements to the model for estimating hard tissue landmarks from soft tissue landmarks, the correlation between the digitized (actual) and estimated or calculated landmarks was significantly improved.
Explore the source record for details and available documents.