Dude420
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Many practitioners have recognized that subjects with a large mandibular plane inclination and long-face morphology are characterized by an extended head posture and a forward inclined cervical column.
Subjects with a large cranio-cervical angle had, on average, large anterior face heights, maxillary and mandibular retrognathism, and a large mandibular plane inclination.
The results showed that the most conspicuous cluster of associations was between growth rotation of the mandible, assessed by structural regional superimposition, and the change in the cranio-cervical angles. Correlation coefficients of about 0.5 indicated that with flexion of the head, i.e. when the cranio-cervical angle was reduced, there was a more pronounced forward growth rotation of the mandible, whereas extension of the head, with an increase of cranio-cervical angle, was accompanied by a reduced forward rotation or even backward rotation of the mandible.
This supported findings, suggested by the cross-sectional study, that growth co-ordination between changes in craniofacial morphology and postural changes exists, and that the co-ordination is centred on the development of the mandible.
the differences in cranio-cervical posture resulted in very different types of facial development. The very small craniocervical angle at 9 years of age was followed by a marked forward growth of both maxilla and mandible, whereas the large cranio-cervical angle at the age of about 9 years resulted in a vertical facial development that could also be seen in the vertical position change of the hyoid bone. The cranio-cervical angle 2–4 years before the peak pubertal growth velocity therefore gives predictive information regarding subsequent facial development.
To provide this explanation all the available evidence was considered and an attempt was made to link the chain of events. There was an association between head posture and craniofacial morphology, and cranio-cervical posture influenced subsequent craniofacial growth. Obstruction of the upper airway could lead to a postural change resulting in extension of the cranio-cervical angle. The precise mechanism of coupling is not known, but it was assumed that it must be present, and it was given the general designation ‘neuromuscular feedback’.
The next link in the chain posed a bigger question. The mechanism was intuitively derived from the results of the first cross-sectional study of associations between head posture and craniofacial morphology (Solow and Tallgren, 1976), and was termed ‘soft-tissue stretching’,which was also used to designate the name of a hypothesis that was proposed (Solow and Kreiborg, 1977) (Figure 4).
The differences in craniofacial morphology could be explained in terms of forces that the soft-tissue layer of facial skin and muscles exert on the facial skeleton. The idea was that this layer would be passively stretched when the head was extended in relation to the cervical column. This would increase the forces on the skeletal structures, and such forces would restrict the forward growth of the maxilla and the mandible, and redirect it more caudally.
Source:
https://pdfs.semanticscholar.org/99e6/d719bb9b3904a7ac19bed02f86c5ed939f30.pdf
Subjects with a large cranio-cervical angle had, on average, large anterior face heights, maxillary and mandibular retrognathism, and a large mandibular plane inclination.
The results showed that the most conspicuous cluster of associations was between growth rotation of the mandible, assessed by structural regional superimposition, and the change in the cranio-cervical angles. Correlation coefficients of about 0.5 indicated that with flexion of the head, i.e. when the cranio-cervical angle was reduced, there was a more pronounced forward growth rotation of the mandible, whereas extension of the head, with an increase of cranio-cervical angle, was accompanied by a reduced forward rotation or even backward rotation of the mandible.
This supported findings, suggested by the cross-sectional study, that growth co-ordination between changes in craniofacial morphology and postural changes exists, and that the co-ordination is centred on the development of the mandible.
the differences in cranio-cervical posture resulted in very different types of facial development. The very small craniocervical angle at 9 years of age was followed by a marked forward growth of both maxilla and mandible, whereas the large cranio-cervical angle at the age of about 9 years resulted in a vertical facial development that could also be seen in the vertical position change of the hyoid bone. The cranio-cervical angle 2–4 years before the peak pubertal growth velocity therefore gives predictive information regarding subsequent facial development.
To provide this explanation all the available evidence was considered and an attempt was made to link the chain of events. There was an association between head posture and craniofacial morphology, and cranio-cervical posture influenced subsequent craniofacial growth. Obstruction of the upper airway could lead to a postural change resulting in extension of the cranio-cervical angle. The precise mechanism of coupling is not known, but it was assumed that it must be present, and it was given the general designation ‘neuromuscular feedback’.
The next link in the chain posed a bigger question. The mechanism was intuitively derived from the results of the first cross-sectional study of associations between head posture and craniofacial morphology (Solow and Tallgren, 1976), and was termed ‘soft-tissue stretching’,which was also used to designate the name of a hypothesis that was proposed (Solow and Kreiborg, 1977) (Figure 4).
The differences in craniofacial morphology could be explained in terms of forces that the soft-tissue layer of facial skin and muscles exert on the facial skeleton. The idea was that this layer would be passively stretched when the head was extended in relation to the cervical column. This would increase the forces on the skeletal structures, and such forces would restrict the forward growth of the maxilla and the mandible, and redirect it more caudally.
Source:
https://pdfs.semanticscholar.org/99e6/d719bb9b3904a7ac19bed02f86c5ed939f30.pdf