| Popis: |
A T THE Children’s Hospital in Boston an attempt is made to correlate whenever possible changes in the mouth with diseases which affect the body generally. Usually, positive correlations of this nature are established only after observations of large numbers of cases. This is true because local manifestations are not always clear, nor are they present in all cases. But if one were to see ten or twelve cases of the same disease group and in that series observe abnormalities of similar nature in three-quarters of them, he would surely be led to believe there was some relation between the deformity and the disease condition. It is such a situation that we will discuss. There are many references in the literature to the relation between muscle function and the development of the bones. In 1892 Wolff, concluded, after studying bones affected by altered function with resulting changes in stresses, that the internal and external architecture of bone depends upon the function to which it is subjected. This view is upheld by most workers today, but it is pointed out that function is not the only factor in producing changes in the form of bones. Murray1 considers “the form and structure of ‘bone is a compromise between many factors.” He goes on to say, “Among all these factors it is clear that one, the direct or indirect influence of mechanical stressing, is predominant in the second phase of development and in later reconstructions, but the multiplicities of factors modifying the influence of this should prevent us from expecting a precise theoretically perfect adaptation to the demands of this single determinant. ” Whatever the other factors are, it is known that bone will change in form as a result of variations in pressure and tension. The rationale of treatment in many orthopedic cases and in orthodontics is based on such knowledge of the physiology of bone. Carey2 states that structural scoliosis is the result of an imbalance between muscle and bone growth. He says ‘ ( Chronic infantile inanition and malnutrition may lead to an asymmetrical decrease in muscle weight and a persistence in the skeletal growth in length. This results in an unequal pull on the spine and the striking of an abnormal muscle-bone balance, which in time results in deformity of the spine, and function is correspondingly diminished.” In paralytic conditions it is a common observation that the bones affected are smaller, weaker, and show evidence of other degenerative changes when compared with corresponding bones in the same patient. |
