Comparison of the efficacy and safety of MAKO robot-assisted total knee arthroplasty versus conventional manual total knee arthroplasty in uncomplicated unilateral total knee arthroplasty a single-centre retrospective analysis.

PURPOSE: To compare the efficacy and safety of MAKO robot-assisted total knee arthroplasty (MA-TKA) with conventional manual total knee arthroplasty (CM-TKA) in patients with end-stage knee osteoarthritis (KOA) during the early postoperative period. METHOD: A retrospective analysis was conducted on 22 patients with KOA who underwent MA-TKA and 26 patients who underwent CM-TKA from April 2023 to July 2023. Hip-knee-ankle angle (HKA), lateral distal femoral angle (LDFA), medial proximal tibial angle (MPTA), American Knee Society Score (AKSS), Forgotten Joint Score-12 (FJS-12), visual analogue scale (VAS), and postoperative complications were recorded and compared between the two groups. RESULT: Both groups successfully completed the surgeries. In terms of radiographic parameters, postoperative one month LDFA and HKA in the MA-TKA group were significantly lower than those in the CM-TKA group (P < 0.05). At the one month follow-up, 19 patients (86.4%) in the MA-TKA group had an HKA less than 3°, compared to 20 patients (76.9%) in the CM-TKA group. Clinically, VAS scores at 24 h, 48 h, and 72 h postoperatively were lower in the MA-TKA group both at rest and during activity. At one month and three months postoperatively, AKSS Function Scores and FJS-12 scores in the MA-TKA group were significantly higher than those in the CM-TKA group (P < 0.05). Regarding postoperative complications, no complications occurred in the MA-TKA group, while one patient in the CM-TKA group experienced postoperative knee stiffness, which resolved after physical therapy, with no statistically significant difference (P > 0.05). CONCLUSION: Compared with conventional manual total knee arthroplasty, MAKO robot-assisted TKA demonstrates better short-term clinical efficacy, achieves better alignment planning, and maintains good safety.

Anchored sutures for fixation of the anterolateral thigh flap and prevention of orocutaneous fistula in oral and oropharyngeal cancer reconstruction.

OBJECTIVE: This study aims to assess the efficacy of anchored sutures (AS) in securing the anterolateral thigh (ALT) flap during oral and oropharyngeal reconstructions, and its impact on the occurrence of orocutaneous fistula (OCF). MATERIALS AND METHODS: A retrospective study was performed on patients who underwent ALT flap reconstruction in our department in the year 2022. The patients were divided into two groups based on whether the AS technique was used. The incidence of OCF was compared between the two groups, and AS-related complications were reported. Fisher's exact test was employed to assess the differences in baseline characteristics and the incidence of OCF between the two groups. RESULTS: The study included 214 patients, with 156 in the conventional suture (CS) group and 58 in the AS group. The incidence of OCF in the AS group was significantly lower compared to that in the CS group (P = 0.039). However, there was a weak correlation between OCF and the AS technique (φ = -0.149). Among the 58 cases in the AS group, three (5.17%) experienced AS-related granuloma (ASRG) as complications. CONCLUSION: The use of ALT flap reconstruction with the AS technique reduces the incidence of OCF; however, ASRG may be a potential complication. CLINICAL RELEVANCE: This study demonstrates the effectiveness of AS technique in securing ALT flaps, leading to a decreased risk of OCF in oral and oropharyngeal defect reconstruction.

Natural fulvic acids inhibit non-small-cell lung cancer through the COX-2/PGE2/EP4 axis: In silico and in vivo assessments.

Purpose: Non-small-cell lung cancer (NSCLC) is a major public health concern with a high incidence worldwide. Coal-derived fulvic acids (FAs) contain functional groups in their chemical structures. Overexpression of cyclooxygenases-2 (COX-2), prostaglandin E2 (PGE2), and the PGE2 receptor EP4 subtype (EP4) can have a potential link with the increased tumor incidence and promoted tumor growth and metastasis in NSCLC. This study aimed to assess the biological roles of coal-derived FAs in the growth and development of NSCLC and to elucidate the underlying molecular mechanisms. Methods: A web-based tool for predicting small-molecule pharmacokinetics (pkCSM) was used to analyze the absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties of FAs. Molecular docking and dynamic simulations were performed to analyze the binding affinities of COX-2 and EP4 to FA. An acute toxicity test and an antitumor study were used to analyze the toxicity and anti-NSCLC effects of FAs. Thirty NSCLC-bearing nude mice were randomly divided into five groups (six mice per group): vehicle control, positive control with 20 mg/kg body weight (BW) 5-fluorouracil, and three treatments with 25, 50, and 100 mg/kg BW FAs. The BW and tumor volume were recorded, and the COX-2, PGE2, and EP4 protein expression were measured and analyzed. Results: Using the predictive pkCSM algorithm, we found that FA did not cause developmental toxicity. Molecular simulations revealed that COX-2 and EP4 expression was inhibited by FA. An acute toxicity test conformed that the maximum tolerated FAs dose was >3.0 g/kg BW. The animal study demonstrated that FA treatment significantly downregulated the expression of COX-2, PGE2, and EP4 in NSCLC-bearing mice compared to that in vehicle control mice (p < 0.01). Conclusions: Natural FAs may exert anti-NSCLC effects through the COX-2/PGE2/EP4 axis.

Precise Coronoidectomy and Zygomatic Arch Reduction for Unilateral Hyperplasia of the Coronoid Process (Jacob's Disease) via Computer-aided Design and Manufacture.

Jacob disease is the new formation of a pseudo-joint between both of enlarged coronoid process and even zygomatic arch. A 23-year-old female patient with facial asymmetry and limited mouth opening was reported. Computed tomography images showed the classic symptom of Jacob disease with a mushroom-shaped tumor mass from the coronoid process a pseudoarthrosis joint with zygomatic arch. Coronoidectomy and zygomatic arch reduction were planned to operate based on computer-aided design/computer-aided manufacturing. During the actual operation, the excision of coronoid process and reconstruction of zygomatic arch were all navigated by 3-dimensional-printed surgical templates as designed through an intraoral approach. As a result, the enlarged coronoid process was smoothly removed without sequela and mouth opening along with facial symmetry were successfully improved. The authors suggested that computer-aided design/computer-aided manufacturing should be considered as an auxiliary technique to shorten operation time and enhance surgical accuracy.

The incidence and risk factors for femoral head necrosis after femoral neck fracture in pediatric patients: a systematic review and meta-analysis.

BACKGROUND: The incidence of avascular necrosis (AVN) after pediatric femoral neck fracture (PFNF) in the literature varies widely, and the risk factors associated with AVN after PFNF are controversial. Therefore, this study aimed to accurately investigate the incidence of AVN after PFNF and systematically evaluate and meta-classify their risk factors. METHODS: A comprehensive search was performed of PubMed, Web of Science, and Embase. The pooled rate and 95% confidence interval (CI) were used to assess the incidence of AVN after PFNF, and pooled odds ratio (OR) were calculated to measure the effect sizes. In addition, we performed subgroup, stratified, and publication bias analyses. RESULTS: A total of 30 articles were included in our meta-analysis, with 303 AVN cases among 1185 patients. The pooled incidence of AVN after PFNF was 22% (95% CI 18%, 27%). Subgroup analyses indicated Delbet type I-IV fracture incidences with AVN of 45%, 32%, 17%, and 12%, respectively. The incidence of AVN after PFNF in Asia was 19%, lower than in Africa at 36%, Europe at 26%, and North America at 23%. In addition, the larger sample size group and the earlier published literature group showed a higher incidence of necrosis. Stratified analyses showed that patient age and Delbet fracture classification were both important factors affecting AVN after PFNF (OR = 1.61, p = 0.02 and OR = 3.02, p < 0.001, respectively), while the time to treatment was not (OR = 0.9, p = 0.71). CONCLUSION: The pooled incidence of AVN after PFNF was ~ 22%; furthermore, the available evidence demonstrates that patient age and Delbet type of fracture were important influencing factors of AVN after PFNF.

Resolvin D2 Reduces Chronic Neuropathic Pain and Bone Cancer Pain via Spinal Inhibition of IL-17 Secretion, CXCL1 Release and Astrocyte Activation in Mice.

Chronic pain burdens patients and healthcare systems worldwide. Pain control remains urgently required. IL-17 (interleukin-17)-mediated neuroinflammation is of unique importance in spinal nociceptive transduction in pathological pain development. Recently, resolvin D2 (RvD2), as a bioactive, specialized pro-resolving mediator derived from docosahexaenoic acid, exhibits potent resolution of inflammation in several neurological disorders. This preclinical study evaluates the therapeutic potential and underlying targets of RvD2 in two mouse models of chronic pain, including sciatic nerve ligation-caused neuropathic pain and sarcoma-caused bone cancer pain. Herein, we report that repetitive injections of RvD2 (intrathecal, 500 ng) reduce the initiation of mechanical allodynia and heat hyperalgesia following sciatic nerve damage and bone cancer. Single exposure to RvD2 (intrathecal, 500 ng) attenuates the established neuropathic pain and bone cancer pain. Furthermore, systemic RvD2 (intravenous, 5 µg) therapy is effective in attenuating chronic pain behaviors. Strikingly, RvD2 treatment suppresses spinal IL-17 overexpression, chemokine CXCL1 release and astrocyte activation in mice undergoing sciatic nerve trauma and bone cancer. Pharmacological neutralization of IL-17 ameliorates chronic neuropathic pain and persistent bone cancer pain, as well as reducing spinal CXCL1 release. Recombinant IL-17-evoked acute pain behaviors and spinal CXCL1 release are mitigated after RvD2 administration. In addition, RvD2 treatment dampens exogenous CXCL1-caused transient pain phenotypes. Overall, these current findings identify that RvD2 therapy is effective against the initiation and persistence of long-lasting neuropathic pain and bone cancer pain, which may be through spinal down-modulation of IL-17 secretion, CXCL1 release and astrocyte activation.

Influence of less invasive hip preservation surgery on subsequent hip arthroplasty for osteonecrosis of the femoral head.

The purpose of this study was to evaluate the outcomes of total hip arthroplasty (THA) following less invasive hip-preserving procedures (LIHPs) and present a critical overview of the literature to aid in better result interpretation. The search time was from the establishment of the database to September 2021, and the outcome indicators were extracted and analyzed by Cochrane Collaboration Review Manager software (RevMan version 5.4). Finally, 10 articles were included in this meta-analysis by searching Chinese databases and English databases. Three of them were published in Chinese, and the remaining studies were published in English. LIHP was further divided into the tantalum rod implantation group and the non-tantalum rod implantation group. The results showed that prior tantalum rod implantation increased the difficulty of conversion to THA, which was reflected mainly in the longer operative time [weighted mean difference (WMD) = 24.50, 95% confidence interval (CI) = 14.09-34.91, P < 0.00001] and greater intraoperative blood loss (WMD = 114.74, 95% CI = 33.52-195.96, P = 0.006), while no significant difference was found between the non-tantalum rod implantation group and the control group. Simultaneously, easier intraoperative fracture [odds ratio (OR) = 5.88, 95% CI = 0.93-37.05, P = 0.06] and stem malalignment (OR = 4.17, 95% CI = 1.18-14.71, P = 0.03) in the LIHP group tended to be observed than in the control THA group. However, there was no significant difference in cup anteversion and inclination angle, ectopic ossification, postoperative Harris Hip Score and survivorship between the LIHP group and the control group. Although LIHP increased the difficulty of the conversion to THA, it does not detrimentally affect the clinical results of subsequent THA in the mid-term follow-up.

Synovial calprotectin for the diagnosis of periprosthetic joint infection: a diagnostic meta-analysis.

BACKGROUND: Periprosthetic joint infections (PJI) are a rare but severe complication of total joint arthroplasty (TJA). However, the diagnosis of PJI remains difficult. It is one of the research that focuses about diagnosis for PJI for majority researchers to discover a novel biomarker. This meta-analysis tried to evaluate diagnostic value of synovial calprotectin for PJI. METHODS: This meta-analysis search of the literature was conducted in PubMed, EMBASE, Web of Science, and the Cochrane Library. Literature quality was appraised using Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) based on RevMan (version 5.3). The diagnostic value of calprotectin for PJI was evaluated by calculating sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), diagnostic score and area under SROC (AUC) based on the Stata version 14.0 software. We conduct subgroup analysis according to the study design, cutoff values, the country of study, and gold standard. RESULTS: Seven studies were included in this meta-analysis. The pooled sensitivity of synovial calprotectin for the diagnosis of PJI was 0.94 (95% CI, 0.87-0.98), and the specificity was 0.93 (95% CI, 0.87-0.96). The pooled AUC, PLR, and NLR for synovial calprotectin were 0.98 (95% CI, 0.96-0.99), 13.65 (95% CI, 6.89-27.07), and 0.06 (95% CI, 0.02-0.15), respectively. The pooled diagnostic score and DOR were 5.4 (95% CI, 3.96-6.85) and 222.32 (95% CI, 52.52-941.12), respectively. CONCLUSION: In summary, this meta-analysis indicates that synovial calprotectin is a promising biomarker of assistant diagnosis for PJI, as well as recommended test for excluding diagnostic tool.

The clinical and radiographic characteristics of avascular necrosis after pediatric femoral neck fracture: a systematic review and retrospective study of 115 patients.

BACKGROUND: Avascular necrosis (AVN) after pediatric femoral neck fracture (PFNF) showed poor prognosis, but its clinical and radiographic characteristics remained unclear. METHODS: A systematic review and a retrospective study were performed to evaluate the clinical and radiographic characteristics of patients with AVN after PFNF. RESULTS: A total of 686 patients with PFNF and 203 patients with AVN from 21 articles were analyzed. Ratliff's classification was used in 178 patients, with types I, II, and III AVN accounting for 58.4%, 25.3%, and 16.3%, respectively. Ratliff's assessment was used in 147 patients, of whom 88.4% had an unsatisfactory prognosis. In retrospective study, 115 patients with a mean age of 13.6 ± 2.0 years were included. The mean interval between AVN and PFNF was 13.7 ± 9.5 months. At the time of diagnosis, 59.1% cases were symptomatic and 65.2% progressed to collapsed stage. Fifty (43.5%), 61 (53.0%), and 4 patients (3.5%) were defined as types I, II, and III , respectively, via Ratliff's classification. Thirteen (11.3%), 40 (34.8%), and 62 patients (53.9%) showed types A/B, C1, and C2 disease, respectively, via the JIC classification. Multivariate analysis demonstrated a strong relation between collapsed stage and symptomatic cases (OR = 6.25, 95% CI = 2.39-16.36) and JIC classification (OR = 3.41, 95% CI = 1.62-7.17). CONCLUSION: AVN after PFNF showed a tendency toward extensive necrotic lesions, presumably resulting in a rapid progression of femoral head collapse. And the symptoms and the JIC classification are other two risk factors of collapse progression.

Diagnostic accuracy of D-dimer in periprosthetic joint infection: a diagnostic meta-analysis.

BACKGROUND: Periprosthetic joint infection (PJI) is one of the most devastating complications after total joint replacement (TJA). Up to now, the diagnosis of PJI is still in a dilemma. As a novel biomarker, whether D-dimer is valuable in the diagnosis of PJI remains controversial. This meta-analysis attempts to determine the diagnostic accuracy of D-dimer in PJI. METHODS: Relevant literature was retrieved from PubMed, Embase, Web of Science, and Cochrane Library (from database establishment to April 2020). Literature quality was evaluated using Revman (version 5.3). The random effect model was used in the Stata version 14.0 software to combine sensitivity, specificity, likelihood ratio (LR), diagnostic odds ratio (DOR), summary receiver operating characteristic (SROC) curve, and area under SROC (AUC) to evaluate the diagnostic value of overall D-dimer for PJI. Meta regression and subgroup analysis were performed according to the threshold, the study design, the sample size, the diagnostic gold standard, the country of study, and the type of sample. RESULTS: A total of 9 studies were included in this study, including 1592 patients. The pooled sensitivity and specificity of D-dimer for PJI diagnosis are 0.82 (95% CI, 0.72~0.89) and 0.73 (95% CI, 0.58~0.83), respectively. The pooled positive likelihood ratio (PLR) and negative likelihood ratio (NLR) were 2.99 (95% CI, 1.84~4.88) and 0.25 (95% CI, 0.15~0.41), respectively. The pooled AUC and diagnostic odds ratios were 0.85 (95% CI, 0.82~0.88) and 12.20 (95% CI, 4.98~29.86), respectively. CONCLUSION: D-dimer is a promising biomarker for the diagnosis of PJI, which should be used in conjunction with other biomarkers or as an adjunct to other diagnostic methods to enhance diagnostic performance.

Accurate movement of jaw segment in virtual 3D orthognathic surgery.

In traditional virtual 3D orthognathic surgery, after repositioning the maxillary segment to the desired position, surgeons usually roughly rotate or adjust the mandibular segment to obtain a relatively good relationship with maxillary dentition to calculate the virtual terminal occlusion splint. However, surgeons are not easy to avoid penetrability, overlap, or an overly large space existing between the maxillary and mandibular dentitions during this process. The present report offered a new method to obtain a suitable virtual terminal occlusal splint that could avoid penetrability, overlap, or an overly large space between the maxillary and mandibular dentitions, and simultaneously accurately moving the maxillary or mandibular segment to the desired position utilizing the planned terminal occlusion plaster models in virtual orthognathic surgery. For double jaw surgery, after aligning the planned plaster models to the 3D maxilla and mandible, we could simultaneously move the maxillary and mandibular segment as a whole that maintain the planned terminal occlusion to the desired position. This present method may enhance the accuracy of 3D virtual orthognathic surgery and save plenty of time spend on virtual surgery simulation, which also offers a useful educational method for training junior surgeons and students.

Finite element analysis of type B condylar head fractures and osteosynthesis using two positional screws.

OBJECTIVE: The aim of this study was to explore the cause of type B condylar head fracture after parasymphyseal impact, and evaluate the biomechanics of osteosynthesis using two positional screws for the repair of this type of fractures. METHODS: A finite element model of the mandible was created, and a parasymphyseal impact was simulated using Mimics 10.01 and Abaqus 6.10 software. The type B condylar head fracture was simulated in the right condyle using a mimics simulation cut with polyplane module according to the analyzed results together with clinical experience, and the left condyle was used as a control. Two positional screws were used for rigid internal fixation of the fracture. von Mises stress distributions in the condyles and screws were analyzed. RESULTS: The von Mises stress generated in parasymphyseal trauma simulation showed a significant concentration in the sagittal direction of the condyle. In two-positional-screw osteosynthesis of the condylar head fractures, stress concentration appeared within the screws in the gap area between the two fractured segments and the area around the screw head. A small amount of stress was distributed in the screw holes and on the posterior surfaces of both segments. The von Mises stress was negligible in the fractured sagittal surfaces. CONCLUSION: It is reasonable to attribute the cause of type B condylar head fracture to the anatomical features of the condyle. The biomechanics of two-positional-screw osteosynthesis revealed that the stress can transmit through the screws to the medial fragments, and the stresses on both sagittal fractured surfaces are minimal.

A novel method to determine the potential rotational axis of the mandible during virtual three-dimensional orthognathic surgery.

During virtual three-dimensional orthognathic surgery in cases where an overlap or penetrability occurs between the 2 jaws due to the repositioning of the maxillary segment, it is necessary to establish a vertical opening of the mandible to obtain a relatively good relationship with the maxillary segment for the fabrication of an intermediate occlusal splint. However, there are few reports that address the precise definition of the rotational axis of the mandible during virtual surgery. Here, we present the idea that the mandible's movement during virtual three-dimensional orthognathic surgery is similar to hinge movement in vivo and developed a method for locating the geometric center of the three-dimensional condyle using Hypermesh software combined with Mimics software. Subsequently, we defined the rotational axis of the mandible based on the located geometric centers of the bilateral condyles, and the mandible was then rotated around the defined axis from the retruded contact position to mimic the hinge movement. Preliminary results indicated that the presented method could approximately mimic the hinge movement of the mandible with a relatively high accuracy in a three-dimensional environment, which may improve the accuracy of virtual intermediate occlusal splint.

Image fusion in craniofacial virtual reality modeling based on CT and 3dMD photogrammetry.

PURPOSE: The aim of this study was to demonstrate the feasibility of building a craniofacial virtual reality model by image fusion of 3-dimensional (3D) CT models and 3 dMD stereophotogrammetric facial surface. METHODS: A CT scan and stereophotography were performed. The 3D CT models were reconstructed by Materialise Mimics software, and the stereophotogrammetric facial surface was reconstructed by 3 dMD patient software. All 3D CT models were exported as Stereo Lithography file format, and the 3 dMD model was exported as Virtual Reality Modeling Language file format. Image registration and fusion were performed in Mimics software. Genetic algorithm was used for precise image fusion alignment with minimum error. The 3D CT models and the 3 dMD stereophotogrammetric facial surface were finally merged into a single file and displayed using Deep Exploration software. Errors between the CT soft tissue model and 3 dMD facial surface were also analyzed. RESULTS: Virtual model based on CT-3 dMD image fusion clearly showed the photorealistic face and bone structures. Image registration errors in virtual face are mainly located in bilateral cheeks and eyeballs, and the errors are more than 1.5 mm. However, the image fusion of whole point cloud sets of CT and 3 dMD is acceptable with a minimum error that is less than 1 mm. CONCLUSIONS: The ease of use and high reliability of CT-3 dMD image fusion allows the 3D virtual head to be an accurate, realistic, and widespread tool, and has a great benefit to virtual face model.

Moving the mandible to the retruded contact position for simulating the hinge movement in virtual three-dimensional orthognathic surgery by integrating the plaster models.

The range of rotation of the mandible during virtual three-dimensional orthognathic surgery is small and may be similar to the hinge movement of the mandible. This current study offers a new method to move the mandible to the retruded contact position (RCP), a position of beginning hinge movement, during virtual three-dimensional orthognathic surgery. During this method, a three-dimensional skull model was reconstructed from the computed tomographic images in the Mimics software. Then the RCP in the patient could be obtained using Gothic arch tracer or swallowing method and was recorded using a wax plate, followed by transferring to plaster models. Subsequently, the plaster models in RCP were scanned using a dental surface scanner and imported into the Mimics software. Finally, we could move the mandible to the RCP based on the registration between the three-dimensional skull model and plaster model for simulating the hinge movement during virtual three-dimensional orthognathic surgery. This may be a small step forward for improving the accuracy of virtual three-dimensional orthognathic surgery.

Material assignment in finite element modeling: heterogeneous properties of the mandibular bone.

PURPOSE: The properties of the biomaterial are normally characterized by heterogeneity on all scales influencing the function and biomechanics. Elastic modulus (EM), which is one of the most important mechanical properties of material, is necessary for finite element modeling and needed to be determined by some methods. The aim of this study is to demonstrate the feasibility of assessment of EM from GrayValue (GV) of computed tomographic image and assignment of material properties in heterogeneous finite element modeling for studying the performance of the mandibular bones. METHODS: Three mandibles obtained from fresh human cadavers were used in this study. All mandibular bones were scanned using computed tomography, and the original data were stored in optical disks. The finite element modeling of the 3 mandibles was meshed using Materialise Mimics 10.01 and Abaqus 6.10 software. Using the empirical expression on relationship between GV and EM, the empirical EM of the meshed mandibular elements were calculated. To verify the empirical EM, actual EM of the three was determined by nanoindentation test using Oliver and Pharr method. The dependence of EM on test regions and loading directions were also discussed. RESULTS: The empirical EM of the mandible element is in the range of 3.7 to 23.4 Gpa, and EM of the cortical element is in the range of 8.6 to 13.6 Gpa. In comparison, the actual EM of cortical bone tested by nanoindentation method is in the range of 10.0 to 22.0 Gpa. The tested EM is varied with the test regions and loading directions. The difference in the values of EM determined by the empirical analysis and by the nanoindentation test is approximately 5.0 Gpa. CONCLUSIONS: A mandibular finite element model with heterogeneous material properties is built. By analyzing the EM value of this model, it is concluded that the actual EM in anterior-posterior direction in mandibular ramus and EM in superior-inferior direction in mandibular body match the empirical EM better than the other directions.

CBCT combining with plaster models: application in virtual three-dimensional subapical segmental osteotomy to obtain more precise occlusal splint.

Anterior subapical segmental osteotomy is considered to be an important surgical technique to obtain functional occlusion and improve the facial profile for patients with maxillary and mandibular protrusion or retrusion, and some complications, such as ischemic necrosis of the distal segment, devitalization of the teeth adjacent to the osteotomy site, and inadequate movement space of segment for obtaining a good occlusion or facial profile, usually exist during surgery. Imprecise measurement of root length, interradicular distance, and intertooth distance based on traditional panoramic radiography that demonstrated existing horizontal distortion and vertical distortion may play an important role in resulting in these problems. In addition, the root is invisible for surgical simulation in traditional plaster models. The recently developed cone-beam computed tomography (CBCT) presents a higher spatial resolution with a lower radiation dose, simultaneously with excellent accuracy and without magnification of images. The presented technique was used to obtain a precise occlusal splint in virtual 3D subapical segmental osteotomy by combining CBCT with plaster models that could guarantee the measurement accuracy of root length, interradicular distance, and intertooth distance, followed by the result of fewer tooth root damage and more precise forecasting of available movement space of jaw segment. Combining with other advantages of virtual 3D surgery, such as precise teeth surface of plaster models, soft tissue simulation, genoplasty simulation, and zygoma plasty simulation, this presented technique may offer a preferable method to patients who need subapical segmental osteotomy.