accuracy of digital and conventional intermediate splints used in orthognathic surgery: a triple-blind randomized clinical trial

Objective: this study compared the accuracy of digitally designed intermediate splints with those fabricated using conventional methods in orthognathic surgery.methods: in this triple-blind randomized clinical trial, 20 patients requiring bimaxillary orthognathic surgery were randomly assigned to receive either digitally designed or conventionally fabricated intermediate splints (n=10). all patients underwent le fort i osteotomy and bilateral sagittal split osteotomy. in the digital group, virtual surgical planning was performed using cone-beam computed tomography (cbct) and intraoral scans to create a three-dimensional model. intermediate splints were then produced using computer-aided design/computer-aided manufacturing (cad/cam) and 3d printing. in the control group, splints were fabricated using conventional model surgery with acrylic resin. to maintain blinding, these splints were subsequently digitized using an intraoral scanner and 3d printed. the primary outcome was surgical accuracy, defined as the absolute difference (mm) between the planned and postoperative maxillary position, measured within 3 days after surgery. secondary outcomes included intraoperative handling, assessed on a 4-point ordinal scale, and fabrication time (hours). the data were analyzed using the independent samples t-test and chi-square test at the significance level of p<0.05.results: the discrepancy between planned and achieved maxillary position was significantly smaller in the digital group (0.70±0.67 mm) compared with the conventional group (1.40±0.84 mm; p=0.044). intraoperative handling and fabrication times did not differ significantly between the groups (p=0.105 and p=0.40, respectively).conclusions: digitally designed intermediate splints demonstrated significantly higher accuracy compared with conventional splints, while fabrication time and intraoperative handling were comparable between the two groups.