In the start of the previous century Schwartz (1926) and later Bjork (1955, 1960) investigated the relationship of head posture and craniofacial growth. When A. Bjork retired from the professorship of Copenhagen orthodontic department, Beni Sollow with his interest in cephalometrics continued the research on the field. Prof B.Sollow conducted a series of observational studies concerning head posture and growth (1976, 1986, 1992)
S.D.Springate of the Eastman Dental Institute, has published at the current issue of the European Journal of Orthodontics, a study that tries to put all those key articles under a critical eye and re-investigate the exact relationship of head posture and craniofacial growth. Here is the link to the abstract of the study.
The main weakness of B.Sollow's studies as pointed by the author of the above study, is the fact that posture is assessed only prior growth and not afterwards. The reasoning B.Sollow used was that since he had two variables with a relation with each-other, the one that occurs earlier is the one responsible for the outcome of the later. With that argumentation the posture, that is there earlier in time, is the one effecting the craniofacial growth that follows.
S.D.Springate designed a study of a sample of 59 children, followed for a period:
- Radiographs and natural headposture registered prior this period of observation
- And the same registrations were taken after the period.
This is the analysis of the sample of the study, where the range of age would have made more sense if given for each sex group (males, females) instead of been pooled for the whole group. The mean age was 11.7 years prior and 15.26 years after the observation period.
For further information about the study you have to refer to the link given, and have access to the EJO current issue.
Conclusions:
The study finds a change in posture between the before and after registrations. This change of natural head posture is related to the postural behavior of the mandible and the tongue. The later affect the mandibular growth direction (horizontal or vertical) and at the same time the cranio-cervical angulation which alters to ensure the adequate pharyngeal airway space.
Reference:
D.G.
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