The role of pressure on regulation of craniofacial bone growth

The regulatory role of pressure on growth and differentiation of the craniofacial skeleton is largely unknown. We devised an experimental model to determine if the graded application of pressure could exert a trophic influence on craniofacial bone, allowing deliberate alteration and reshaping of the facial skeleton. To examine this question, 18 kittens were used to determine the adverse morphological sequelae after orbital evisceration and to compare the ability to remedy such facial deformity with the use of an inert implant or pressure-induced tissue expansion. In addition to detailed craniometric measurements of the cranial, orbital, and midfacial regions, histological analyses as well as radiographic and gross morphological comparisons were evaluated. Our results demonstrate a severe asymmetry and constriction in the orbital and midfacial regions resulting from orbital evisceration in the growing kitten. Placement of an inert implant will help to ameliorate only some of these adverse sequelae, whereas graded application of pressure appears to direct craniofacial bone growth, resulting in normal bony histology and improved facial form. We affirm that regional growth disturbances can alter normal facial development and that the regulatory role of pressure on bone growth can be exploited to dynamically correct abnormal craniofacial anatomy.