Three-dimensional surgical accuracy between virtually planned and actual surgical movements of the maxilla in two-jaw orthognathic surgery

Abstract

Three-dimensional surgical accuracy between virtually planned and actual surgical movements of the maxilla in two-jaw orthognathic surgery Objective: To investigate the three-dimensional (3D) surgical accuracy between virtually planned and actual surgical movements (SM) of the maxilla in twojaw orthognathic surgery. Methods: The sample consisted of 15 skeletal Class III patients who underwent two-jaw orthognathic surgery performed by a single surgeon using a virtual surgical simulation (VSS) software. The 3D cone-beam computed tomography (CBCT) images were obtained before (T0) and after surgery (T1). After merging the dental cast image onto the T0 CBCT image, VSS was performed. SM were classified into midline correction (anterior and posterior), advancement, setback, anterior elongation, and impaction (total and posterior). The landmarks were the midpoint between the central incisors, the mesiobuccal cusp tip (MBCT) of both first molars, and the midpoint of the two MBCTs. The amount and direction of SM by VSS and actual surgery were measured using 3D coordinates of the landmarks. Discrepancies less than 1 mm between VSS and T1 landmarks indicated a precise outcome. The surgical achievement percentage (SAP, [amount of movement in actual surgery/ amount of movement in VSS] × 100) (%) and precision percentage (PP, [number of patients with precise outcome/number of total patients] × 100) (%) were compared among SM types using Fisher's exact and Kruskal-Wallis tests. Results: Overall mean discrepancy between VSS and actual surgery, SAP, and PP were 0.13 mm, 89.9%, and 68.3%, respectively. There was no significant difference in the SAP and PP values among the seven SM types (all p > 0.05). Conclusions: VSS could be considered as an effective tool for increasing surgical accuracy.

Characterization of facial asymmetry phenotypes in adult patients with skeletal Class III malocclusion using three-dimensional computed tomography and cluster analysis

“…After each data set was imported into the ON3D program (3DONS, INC., Seoul, Korea), 3D-CT images were re-orientated using the horizontal, coronal, and mid-sagittal planes ( Figures 1 and 2 , Table 1 ). The definitions of landmarks and reference planes used in the present study were adopted from the methodology of Hong et al 17 The N point was registered as the origin (0, 0, 0) of the Cartesian coordinate system.…”

Reproducibility of Manual Transfer of the Clinical Natural Head Position: Influence on the Soft Tissue and Hard Tissue Position of 3-Dimensional Virtual Surgical Planning

“…To put this into a broader perspective, the surgical error in the transfer of VSP to the patient has proven to be less than or equal to 2 mm for the maxilla in all 3 planes. [13][14][15] Thus, the total error that was introduced by the process of 3D VSP often exceeds the magnitude of the surgical error. From this point of view, the error introduced by the 3D VSP is considered clinically relevant in the present study as it may lead to a suboptimal postoperative result.…”

A surgery-first approach using single-jaw rotational mandibular setback in low-angle mandibular prognathism

“…Surgery was done as planned except for a 0.5 mm deficient transverse correction and 0.8 mm more bite opening (Fig 4). 16 Postsurgical orthodontic treatment was started 1 month after surgery (Fig 5). For maxillary molar distalization, two 2.0 3 8-mm mini-implants were placed in the midpalate, and a lever plate was placed over the platforms of the mini-implants.…”