ABSTRACT
Virtual surgical planning (VSP) is state of the art in routine clinical work. Visualization of soft tissue changes adds important information for surgical planning. The aim of this study was to evaluate accuracy of soft tissue prediction of 2 VSP systems in patients undergoing an intraoral quadrangular Le Fort II osteotomy. METHODS: VSP was performed with the software application IPS Case Designer (IPS) and Dolphin Imaging 11.95 (DOL) in bone and soft tissue structure. Distances were measured at the 3 levels of the face at the infraorbital rim, the sinus floor, and the lateral incisor level with 2 VSP systems (DOL and IPS). RESULTS: A convenience sample of 19 patients was included in the study with a mean age of 21.9 years. From cranial to caudal, mean differences between simulation and postintervention data were as follows: infraorbital rim level: DOL and ST0: mean difference: 2.90 mm; IPS and ST0: 1.70 mm; sinus floor level: DOL and ST0: mean difference: 3.57 mm; IPS and ST0: 1.34 mm; and lateral incisor level: DOL and ST0: mean difference: 2.48 mm; IPS and ST0: 2.25 mm. CONCLUSIONS: Generally, both VSP systems are suitable for planning an intraoral quadrangular Le Fort II osteotomy. Especially in the infraorbital region, improvement of the algorithm is required for trustworthy prediction of soft tissue changes.
ABSTRACT
BACKGROUND: Today virtual surgical planning (VSP) is a standard method in maxillofacial corrective surgery and is the key to reach satisfactory esthetic outcomes. The purpose of this study was to evaluate usability of three established virtual surgical planning software applications by comparing feasibility, time consumption, and costs in a standardized workflow for a modified intraoral quadrangular Le Fort II osteotomy (IQLFIIO). RESULTS: A cross-sectional study was performed based on retrospective and re-planned data of patients with midfacial deficiency treated by modified IQLFIIO, using three software applications: IPS Case Designer ®, Dolphin Imaging ®, and ProPlan CMF ®. Feasibility: All evaluated steps of the VSP procedure could be successfully performed in all three evaluated applications. In all software packages, it was possible to design the surgical splints with CAD/CAM technology. Working time: The mean value of time needed was IPS Case Designer ®, 36.5 min; Dolphin Imaging ®, 33.6 min; ProPlan CMF ®, 45.5 min. We found statistical significant difference between ProPlan CMF ® and Dolphin Imaging ® (p value, 0.02). COSTS: Asset costs for acquiring the software, license fee, license possibilities, paying for support services, and service contracts were evaluated and are found in similar ranges. CONCLUSION: All three tested software applications are usable for virtual planning of an IQLFIIO and splint production by CAD/CAM technology. Successful movement of bone segments and overlaying soft tissues proved feasibility. Time consumption and costs were found in similar ranges.
ABSTRACT
PURPOSE: In planning intraoral quadrangular Le Fort II osteotomy (IQLFIIO), simulation of hard and soft tissue changes will be important at the infraorbital, Le Fort I, and incisor level. The aim of our study was to evaluate a new method for visualization and quantification. MATERIALS AND METHODS: Three different methods of quantification were compared: the point-to-point (PTP) measurement, which has been viewed as the reference standard; part comparison analysis (PCA); and a new method, the midfacial advancement line (MFAL) measurement. We performed a measurement comparison study using the Bland-Altman method to measure agreement and enrolled patients with midfacial deficiency and Class III malocclusion who had undergone IQLFIIO. The primary predictor variable was the method of measurement. The primary outcome variable was the amount of midfacial advancement. We also investigated the time required, visualization quality, and interobserver agreement. RESULTS: The sample included 12 subjects with a mean age of 21.6 years; 7 patients were male. The PTP and MFAL showed no significant observer dependence. The advancement measured with PTP and MFAL showed no significant differences. However, the advancement measured using MFAL and PCA showed a significant difference. The highest rating of visualization was found for MFAL. The time requirements were similar for all 3 methods. CONCLUSIONS: Our results have shown that the MFAL is a suitable method for visualization and quantification of soft and hard tissue changes at all 3 face levels in 1 image. It could be a valuable tool for virtual planning of midfacial advancement surgery.
Subject(s)
Malocclusion, Angle Class III , Orthognathic Surgery , Orthognathic Surgical Procedures , Adult , Cephalometry , Face/anatomy & histology , Humans , Male , Maxilla , Osteotomy, Le Fort , Treatment Outcome , Young AdultABSTRACT
Orthognathic surgery treatment (OGS) after orthodontic treatment of dentofacial deformities is a widely performed procedure, often accompanied by a bilateral sagittal split osteotomy (BSSO). Positioning of the condyle during this procedure is a crucial step for achieving optimal functional and anatomical results. Intraoperatively poorly positioned condyles can have a negative effect on the postoperative result and the patient's well-being. Changes of the condylar position during OGS Procedures and its effects on the temporomandibular joint in orthognathic surgical interventions (OGS) are subject of scientific discussions. However, up to date, no study has investigated the role of condyle position in the surgery first treatment concept. The aim of this study was to investigate the influence of OGS on the three-dimensional position of the condyle in the joint in a surgery first treatment concept without positioning device and to record the change in position quantitatively and qualitatively. Analysis of our data indicated that OGS in surgery first treatment concept has no significant effect on the position of the condyle and the anatomy of the temporomandibular joint.
