Longitudinal study on craniofacial growth following Le Fort I maxillary osteotomy in adolescent monkeys.

The present study was conducted to investigate the effects of Le Fort I maxillary osteotomy on craniofacial growth in adolescent monkeys. Twenty monkeys were used, of which eight served as control and twelve for experiment. All monkeys received tantalum implants, whereas experimental monkeys underwent Le Fort I osteotomy. Serial lateral cephalograms were taken before and immediately after surgery, and thereafter every month. Craniofacial growth was investigated by evaluating both repositionings of anatomical landmarks and implants, and dimensional changes. No significant differences between the experimental and control groups were observed in midfacial growth. Maxillary growth was not significantly affected excluding the posterior region of the maxilla. Condylar growth of the mandible was significantly influenced, and the overall length of the mandible in the experimental group was much less as compared to the controls. However, the length of the body of the mandible was not significantly affected, indicating a catch up growth of the mandible. It is shown that craniofacial growth is somewhat retarded, however, the maxilla and mandible experience harmonious growth even after surgery. Thus, it is indicated that the maxillary osteotomy is applicable to growing patients as well as adults, in terms of the craniofacial growth after surgery.