Craniofacial growth differences between low and high MP-SN angle males: a longitudinal study

Craniofacial growth was followed longitudinally in two groups of boys with low and high MP-SN angles. The purpose was, first, to reveal group differences in dimensional change, and second, to find whether such differences were associated with a group difference in mandibular growth rotation. Group differences in dimensional change were explained by a difference in matrix rotation of the mandibular corpus, especially in the 6- to 12-year period. In the 12- to 15-year period, matrix rotation was similar in the two groups and so were dimensional changes. Morphologically, dimensional group differences in the 6- to 12-year period were theoretically compatible with the fact that mandibular rotation was clearly more forward in the low angle than in the high angle group. Statistically, dimensional variables with significant group difference were correlated strongly with matrix rotation and, in most cases, non-significantly with intramatrix rotation.

Correlations among craniofacial angles and dimensions in Class I and Class II malocclusions

In normal and Class I malocclusions, ramus and mandibular angles are found to correlate most strongly with cranial base dimensions rather than angles, whereas in Class II malocclusions these angles tend to relate more closely to the cranial base angles.

Rotational effects of S-N on the dentoskeletal pattern within the range of normal

The range of orientation of SN in relation to the craniofacial centroid line in a Class I sample with "acceptable" profiles is divided into three groups for comparison with facial dentoskeletal structures and evaluation of the adaptations among them. This manuscript was originally submitted September, 1986.

A new cephalometric parameter to aid in dental base relationship analysis

The cephalometric literature is rich with different craniofacial analyses. However, since these analyses are only descriptive for the clear skeletal discrepancies and somewhat handicapped for borderline cases, an investigation was designed to assess the dental base relationship in the human lateral skull cephalostat radiograph. A number of existing measurements were reviewed, and a new measurement, based upon anatomical points which could prove to be more reliable, was introduced.

Differential growth of the female face in the anteroposterior dimension

This study contrasts the growth rates of the craniomaxillary and mandibular dimensions. Longitudinal data from lateral head cephalograms of 18 female subjects, between 3 and 18 years old, were used. All of the subjects had yearly cephalograms available and none had received orthodontic treatment. Four linear distances included anterior cranial base, maxillary length and mandibular length and four angular measurements included ANS-S-N, ANS-N-S, Gn-S-N and Gn-N-S. The mandible lagged in size by 4 years relative to anterior cranial base length and by 2 years relative to maxillary length at 5 years of age. There was an incremental gradient of growth from S-N downward to Ar-Pog such that dimensions successively showed a greater relative amount of growth during the entire period of development. The proportional displacement of nasion and anterior nasal spine maintained a constant S-N-ANS angle. The increase in angle S-N-Gn was due to proportionally greater increase in mandibular length relative to anterior displacement of nasion. The different rates of dimensional increments from anterior cranial base to mandible result in differential growth affecting the spatial relationship of maxilla and mandible in the sagittal plane. Skeletal discrepancies in maxillomandibular relationships between 4 and 10 years of age is a normal transient developmental characteristic.