In vivo analysis of bone strain about the sagittal suture in Macaca mulatta during masticatory movements

In vivo strain gauge analysis demonstrated that tensile bone strain is transmitted along the cra-nial vault to the parasagittal region during iso-tonic temporalis contraction. This strain is suf-ficient to cause measurable separation of the sagittal suture, and thus could influence growth at the sutural margins. J Dent Res 57(9-10):904-908, Sept.-Oct. 1978 Early views of craniofacial growth regarded the increase in size and change in shape and position of the bones of the cranial vault to be the result of ectocranial deposition and endo-cranial resorption, with the sutures playing little or no role in the increase in skull size.'2 Later views held that the cranial vault grows actively at the sutures. While this has remained the generally accepted view through the pres-ent day, disagreement remains concerning the local control mechanisms affecting sutural growth, i.e., the source of the force which causes cranial bones to move apart during growth and initiate bone formation at the sutural margins. Weinmann and Sicher3 proposed that an intrinsically regulated proliferation of sutural tissue is the driving force for the separation and growth of the cranial bones. The works of Moss,4 Girgis and Pritchard5-7 and Young,8 however, indicate that the separating force is largely the result of the expansive growth of the brain which separates the cranial bones and results in compensatory osteogenic deposition at the sutural margins. Another opinion held that the growth of the cartilaginous synchro-doses of the cranial base provides the forc