To assess the impact of changes in practice patterns, hospital charges (overall and component charges excluding professional fees) for 1992 were compared to 1985 data for three orthognathic surgical procedrues: bilateral sagittal split osteotomy (BSSO), Le Fort I osteotomy (LFI), and a combination of both (BSSO/LFI). Data for 1992 were obtained for 59 patients (26 BSSO, 18 LFI, 15 BSSO/LFI). Secondary analysis of similar data for 1985 included 77 patien ts (27 BSSO, 16 LFI, 34 BSSO/LFI). Changes in clinical practice from 1985 to 1992 reduced mean length of stay (days): BSSO 3.2 to 1.2, LFI 3.7 to 1.4, BSSO/LFI 4.1 to 1.8. Mean total charges 9dollars) increased: BSSO 3,086 to 5,023, LFI 3,538 to 6,784, BSSO/LFI 4,778 to 8,816. If 1992 charges are expressed in 1985 dollars, ancillary, pharma cy, and room charges all are reduced. Charges attendant to the surgical procedure (anesthesia, operating room supply, and recovery) were just over half of total charges in 1985. By 1992, these components escalated to 80% of total charges. Most notable was the increase in supply charges. Charges for rigid fixation were a major component of increased supply charges in 1992. Surgeons minimally influence charges attendant to the operating room and postanesthesia recovery, the major components of total charges in 1992. Quality can be maintained with reduction in some charge categories, but these components total less than 25% of the patient's bill. Technology changes benefit patients, but a judgment must be made weighing benefits against increased helath care costs.