Osteotomy Guides Research Articles

Prevention of Subperiosteal Implant Complications with a Novel Osteotomy Guide

Prevention of Subperiosteal Implant Complications with a Novel Osteotomy Guide

Office-Based Digital Workflow for Managing Old Mandibular Fracture Malunion: Use of Short-Segment Drilling and Osteotomy Guides With Predictive Holes.

Treating old mandibular fractures with malunion is challenging due to the need for osteotomy and interference between bone segments, complicating occlusal restoration. This technical note introduces a novel office-based digital workflow utilizing surgical guides. Preoperative computed tomography (CT) data were imported into MIMICS software for virtual surgical planning to precisely realign bone fragments based on anatomical and occlusal relationships. A pre-bent reconstruction plate was adapted to a 3-dimensional-printed mandible model, and cone beam CT scans captured detailed screw path data. This information was used in 3-matic software to design short-segment drilling guides (SSDGs), and osteotomy guides with predictive holes. These guides facilitated accurate bone osteotomy and realignment during surgery. This workflow addresses the limitations of previous SSDGs, offering a reliable solution for managing malunion in old mandibular fractures. The approach reduces surgical complexity, enhances precision, and streamlines treatment, providing an innovative method for challenging mandibular fractures.

An exploratory study of the impact of CT slice thickness and inter-rater variability on anatomical accuracy of malunited distal radius models and surgical guides for corrective osteotomy.

High-resolution CT images are essential in clinical practice to accurately replicate patient anatomy for 3D virtual surgical planning and designing patient-specific surgical guides. These technologies are commonly used in corrective osteotomy of the distal radius. This study evaluated how the virtual radius models and the surgical guides' surface that is in contact with the bone vary between experienced raters. Further, the discrepancies from the reference radius of surgical guides and radius models created from CT images with slice thicknesses larger than the reference standard of 0.625mm were assessed. Maximum overlap with radius model was measured for guides, and absolute average distance error was measured for radius models. The agreement between the lower-resolution guides surface and the raters' guide surface was evaluated. The average inter-rater guide surface overlap was -0.11mm [95% CI: -0.13-0.09]. The surface of surgical guides designed on CT images with a 1mm slice thickness deviated from the reference radius within the inter-rater range (0.03mm). For slice thicknesses of 1.25mm and 1.5mm, the average guide surface overlap was 0.12mm and 0.15mm, respectively. The average inter-rater radius surface variability was 0.03mm [95% CI: 0.025-0.035]. The discrepancy from the reference of all radius models created from CT images with a slice thickness larger than the reference slice thickness was notably larger than the inter-rater variability but, excluding one case, did not exceed 0.2mm. The results suggest that 1mm CT images are suitable for surgical guide design. While 1.25mm slices are commonly used for virtual planning in hand and forearm surgery, slices larger than 1mm may approach the limit of clinical acceptability. Discrepancies in radius models were below 1mm, likely below clinical relevance.

Digital Simulation and Designing of a Novel Osteotomy Guide for Autotransplantation in the Anterior Region.

Autotransplantation of teeth (ATT) is a viable treatment option for replacing teeth lost due to various reasons. Periodontal ligament (PDL) on the donor tooth is one of the most crucial factors determining the success of ATT. To preserve the PDL during surgery and improve the success rate of ATT, digital dentistry has been applied to ATT. In this article, a digital workflow including surgical simulation, a three-dimensional (3D) replica fabrication, and a novel osteotomy guide design is introduced. Digital simulation of ATT on a patient's integrated model enables visualization of anatomical structures and the 3D position of the donor tooth prior to the actual surgery. The 3D-printed osteotomy guide allows the transfer of the direction and depth of the planned osteotomy into the intraoral environment. The 3D replica helps prepare the recipient site before the actual transplantation, which minimizes the extra-alveolar time of the donor tooth and decreases trauma during the try-in process. The proposed virtual planning and the use of the guide and the 3D replica can facilitate the surgical procedures while minimizing complications.

Digital Surgical Guides in Mandibular Genioplasty: Evaluating Precision Against Conventional Techniques.

Mandibular genioplasty, a central procedure in oral and maxillofacial surgery, has traditionally relied on surgeon experience with potential limitations in precision. The advent of digital methods, particularly computer-aided design/computer-aided manufacturing (CAD/CAM), offers a promising alternative. This study aims to evaluate the efficacy of digital surgical guides in improving the precision of mandibular genioplasty. A prospective analysis of 50 patients undergoing genioplasty was performed, 30 in the experimental group using digital surgical guides and 20 in the control group using traditional methods. Three-dimensional reconstructions were obtained using cone-beam computed tomography (CBCT) and digital scans. Osteotomy guides were 3D-printed based on group assignment. Postoperatively, accuracy was assessed by measuring distances between landmarks. The experimental group showed significantly reduced horizontal positioning errors in genioplasty advancement, with no significant differences in vertical errors. For genioplasty retraction, the experimental group showed fewer vertical positioning errors, while horizontal errors remained consistent. The use of digital surgical guides in mandibular genioplasty significantly improves surgical accuracy, resulting in improved outcomes and patient satisfaction. This study highlights the potential of digital methods in refining oral and maxillofacial surgical procedures. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Poster 238: Accuracy, Safety, and Cost of Patient-Specific Cutting Guides for Alignment-Correcting Osteotomy

Objectives: The purpose of this study was to determine the cost, accuracy of radiographic correction, and safety with respect to complication rates and fluoroscopic usage in patient-specific cutting guides (PSCG) osteotomies compared to an age- and body mass index (BMI)-matched group of controls using standard cutting guides (SCG). Methods: Patients were retrospectively reviewed between 2017 and 2022 at a single urban academic institution. Patients undergoing high tibial osteotomy (HTO) or distal femoral osteotomy (DFO) with PSCG (Bodycad 3d, Quebec, Canada) were identified. Traditional osteotomies were selected for the SCG group using propensity matching based on age, sex, BMI, osteotomy type. All procedures were performed by 1 of 2 fellowship-trained sports orthopaedic surgeons. Procedure time, fluoroscopy time, tourniquet time, and concomitant procedures were extracted from operative notes. Blinded, 2-reader hip-knee-ankle (HKA), posterior tibial slope (PTS) and mechanical axis deviation (MAD) measurements were performed on pre- and postoperative weightbearing radiographs for each procedure. Intraclass correlation coefficients (ICCs) were calculated to determine the reliability between the intended intraoperative correction of HKA and/or PTS the measured result on postoperative radiographs. A time-driven activity-based costing (TDABC) analysis was performed to compare costs of PSCG versus SCG. Results: Forty-two patients were included in the final analysis. Each group was 47.6% female, with 11 HTOs and 10 DFOs performed in each group. Final HKA (2.7° vs 1.9°, p = 0.355), PTS (1.6° vs 2.6°, p = 0.794) and MAD (10.2 vs 5.8 mm, p = 0.214) did not significantly differ between SCG and PSCG groups (MAD seems higher for SCG. The ICC between the intended and measured HKA correction was 0.841 (good) in the PSCG group and 0.623 (moderate) in the SCG group. PSCG osteotomies averaged 18.5 minutes less (p = 0.392) and required 16.7 minutes less tourniquet time (p = 0.121). Fluoroscopy time was significantly lower in the PSCG group compared to SCG (99 vs 43 seconds, p < 0.001), as well as radiation dose (7.8 vs 2.9 mGy, p = 0.013). TDABC analysis demonstrated a base cost of $21,067 for PSCG and $23,896 for SCG. When the cost of the cutting guide and pre-operative imaging were included, PSCG was $2,829 more expensive than SCG. There was a lower, though non-statistically significant, rate of hinge fractures (9.5% vs 33.3%, p = 0.130) and return to the OR (4.8% vs 19.0%, p = 0.343) when comparing PSCG and SCG groups. Conclusions: Both traditionally guided osteotomies and PSCG-guided osteotomies accurately corrected lower extremity malalignment. Utilization of PSCG resulted in similar procedure times and cost. PSCG required less fluoroscopy and resulted in less radiation to conventional osteotomy and trended toward a decreased rate of postoperative complications.

3D pre-operative planning and patient-specific guides for re-directional peri-acetabular osteotomy in children and adolescents

Surgical procedures to correct hip dysplasia associated with subluxation or dislocation of the femoral head are complex. The 3D geometric abnormalities of the acetabulum and proximal femur vary across patients. We, therefore, suggest a patient-specific surgical treatment involving computer-assisted 3D planning of the peri-acetabular osteotomies, taking into account the femoral head position; 3D printing of patient-specific guides for the cuts, repositioning, and fixation; and intra-operative application of the simulated displacements with their fixation. Level of evidenceIV.

Efficacy of personalized 3D-printed osteotomy guide in maximizing fibular utilization and minimizing graft length for reconstruction of large mandibular defect.

The study addresses the long-standing challenge of insufficient length in vascularized fibular flaps when reconstructing large mandibular defects that require dual-barrel grafts. Employing personalized 3D-printed osteotomy guides, the study aims to optimize fibular utilization and minimize the required graft length. Two reconstruction methods for distal bone defects were compared: a fold-down (FD) group that employed a specialized osteotomy guide for folding down a triangular bone segment, and a traditional double-barrel (DB) group. Metrics for comparison included defect and graft lengths, as well as the graft-to-defect length ratio. Postoperative quality of life was assessed using the University of Washington Quality of Life questionnaire (UW-QoL). Both FD and DB groups achieved successful mandibular reconstruction. Despite larger defects in the FD group (117 ± 31.35mm vs 84 ± 35.34mm, p = 0.028), the used fibula length was not statistically longer in the FD group. The median ratio of graft-to-defect length was also lower in the FD group (1.327 vs 1.629, p = 0.024), suggesting that FD required only 82.47% of the graft length needed in the DB approach. Quality of life scores post-surgery were comparable between the groups. Personalized 3D-printed osteotomy guides enhance fibula graft efficacy for reconstructing larger mandibular defects, necessitating shorter graft lengths while preserving postoperative quality of life. This study confirms the utility of 3D printing technology as an effective and precise tool in orthopedic surgery, particularly for complex reconstructions like large mandibular defects. It suggests a viable alternative that could potentially revolutionize current practices in bone grafting.

3D-assisted corrective osteotomies of the distal radius: a comparison of pre-contoured conventional implants versus patient-specific implants

PurposeThere is a debate whether corrective osteotomies of the distal radius should be performed using a 3D work-up with pre-contoured conventional implants (i.e., of-the-shelf) or patient-specific implants (i.e., custom-made). This study aims to assess the postoperative accuracy of 3D-assisted correction osteotomy of the distal radius using either implant.MethodsTwenty corrective osteotomies of the distal radius were planned using 3D technologies and performed on Thiel embalmed human cadavers. Our workflow consisted of virtual surgical planning and 3D printed guides for osteotomy and repositioning. Subsequently, left radii were fixated with patient-specific implants, and right radii were fixated with pre-contoured conventional implants. The accuracy of the corrections was assessed through measurement of rotation, dorsal and radial angulation and translations with postoperative CT scans in comparison to their preoperative virtual plan.ResultsTwenty corrective osteotomies were executed according to their plan. The median differences between the preoperative plan and postoperative results were 2.6° (IQR: 1.6–3.9°) for rotation, 1.4° (IQR: 0.6–2.9°) for dorsal angulation, 4.7° (IQR: 2.9–5.7°) for radial angulation, and 2.4 mm (IQR: 1.3–2.9 mm) for translation of the distal radius, thus sufficient for application in clinical practice. There was no significant difference in accuracy of correction when comparing pre-contoured conventional implants with patient-specific implants.Conclusion3D-assisted corrective osteotomy of the distal radius with either pre-contoured conventional implants or patient-specific implants results in accurate corrections. The choice of implant type should not solely depend on accuracy of the correction, but also be based on other considerations like the availability of resources and the preoperative assessment of implant fitting.

Virtual planning for mandible resection and reconstruction

Abstract In mandibular reconstruction, computer-assisted procedures, including virtual surgical planning (VSP) and additive manufacturing (AM), have become an integral part of routine clinical practice. Especially complex cases with extensive defects after ablative tumor surgery benefit from a computer-assisted approach. Various CAD/CAM-manufactured tools such as surgical guides (guides for osteotomy, resection and predrilling) support the transition from virtual planning to surgery. Patient-specific implants (PSIs) are of particular value as they facilitate both osteosynthesis and the positioning of bone elements. Computer-based approaches may be associated with higher accuracy, efficiency, and superior patient outcomes. However, certain limitations should be considered, such as additional costs or restricted availability. In the future, automation of the planning process and augmented reality techniques, as well as MRI as a non-ionizing imaging modality, have the potential to further improve the digital workflow.

Posterior Opening-Wedge Osteotomy for Posterior Tibial Slope Correction of Failed Anterior Cruciate Ligament Reconstruction

A large posterior tibial slope (PTS) has been widely recognized as a potential risk factor in loosening and retear after anterior cruciate ligament reconstruction. Anterior closed-wedge osteotomy is an effective surgical approach to mitigate this risk factor but presents several disadvantages. We describe in this Technical Note an original PTS correction technique called the posterior open-wedge osteotomy. The posterior surface of the proximal tibia is exposed, and 2 K-wires are inserted anteroposteriorly as osteotomy guides, and one wire is inserted mediolaterally as a hinge blocker. The osteotomy is performed from the posterior side and advanced to the anterior side using a single-bladed reciprocating saw. The slope is corrected by opening the osteotomy plane posteriorly with a spreader. The correction is maintained by inserting the harvested fibula fragments into the open space, and the fixation is completed with a locking plate to ensure firm fixation and allow early rehabilitation. This procedure can be an effective solution for patients with various risk factors for retear of the anterior cruciate ligament graft, including abnormal PTS.

Three-dimensional-printed patient-specific guides for tibial deformity correction in small-breed dogs.

To describe the use of patient-specific 3-D-printed osteotomy, reduction, and compression guides for tibial closing wedge osteotomy in small-breed dogs. 6 dogs with unilateral tibial deformities. Six small-breed dogs with 1 or a combination of tibial deformities, including excessive tibial plateau angle, valgus, and torsion, were scheduled to undergo tibial closing wedge osteotomy using patient-specific 3-D-printed osteotomy, reduction, and compression guides. The location and orientation of the wedge osteotomy were determined based on CT data using computer-aided design software. After the tibial deformities were corrected, postoperative CT or radiographs were obtained to compare the achieved tibial limb angles with the planned angles. Clinical evaluation and radiographic follow-up were performed on all dogs. Guides were successfully positioned at each specific location, and osteotomies were performed without radiation exposure or observer assistance in all dogs. Tibial deformities were corrected with angular errors of 1.8 ± 1.4°, 2.3 ± 2.1°, and 2.6 ± 1.3° in the sagittal, frontal, and transverse planes, respectively. Mild complications resolved within 1 month in 3 dogs, and revision surgery was not required. Five dogs improved to the normal gait (mean, 14.8 ± 6.6 weeks), and 1 dog recovered a satisfactory gait 24 weeks after surgery. All limbs healed 14 ± 4.7 weeks after surgery. Patient-specific 3-D-printed osteotomy, reduction, and compression guides can provide effective assistance allowing accurate correction of tibial deformities. Their use yields good clinical outcomes in small-breed dogs.

Corrective Surgery Using Virtual Surgical Simulation and a Three-Dimensional Printed Osteotomy Guide: A Case Report

Corrective Surgery Using Virtual Surgical Simulation and a Three-Dimensional Printed Osteotomy Guide: A Case Report

Use of patient-specific guides and 3D model in scapula osteotomy for symptomatic malunion

BackgroundScapular osteotomy for malunion can lead to resolution of pain and functional improvement in scapula fracture sequelae. Understanding three-dimensional bone morphology and analysing post-traumatic deformity is the main step of planning and the key to success of the procedure. 3D models and patient-specific guides are a growing technology to enhance accuracy of planning and to assist during surgery.Case presentationWe report the case of a 50 years old male, complaining of pain and limited function after a malunited scapular body fracture. Clinical assessment showed a severe impairment of shoulder function with active and passive forward flexion limited to 80°, absent external rotation, and internal rotation limited to the buttock. X-rays and CT scan showed an excessive lateral border offset of 53 mm and complete displacement of the glenoid segment anteriorly and medially to the scapular body, with impingement between the lateral most prominent scapular bone spur and humeral shaft. Glenopolar angle was 19°, scapular body angulation on the sagittal plane was 12°. Corrective osteotomy was planned on a virtual interactive rendering and on 3D printed models. Patient-specific guides were developed to perform a body-spine osteotomy with removal of a bone wedge, and a glenoid-spine osteotomy; a patient-specific wedge spacer was used to hold the reduction during plate fixation. Follow-up up to 12 months after surgery demonstrated improvement in scapula anatomy, shoulder girdle function, and patient-reported outcomes.ConclusionsFor the first time in scapula malunion surgery, patient-specific osteotomy guides were succesfully used during surgery to perform osteotomies and to assist in reduction maneuvers.

A 3D-printed patient-specific modular implants for pelvic reconstruction of bone tumors involving the sacroiliac joint.

Background: Current reconstruction methods of the pelvic ring after extensive resection of tumors involving the sacroiliac joint have a high incidence of failure. We aimed to study the effect of 3D-printed patient-specific implant reconstruction to show that this method is stable and has a low risk of failure. Methods: Between February 2017 and November 2021, six patients with bone tumors involving the sacroiliac joint (Enneking I + IV) who received 3D-printed patient-specific implants for pelvic reconstructive surgery were retrospectively analyzed. Two female and four male patients with a mean age of 41.83years (range 25-65years) were included. Two were osteosarcomas, two chondrosarcomas, one malignant fibrous histiocytoma, and one giant cell tumor of bone. For each patient, preoperative osteotomy guides were designed to ensure accurate tumor resection and individualized prostheses were designed to ensure a perfect fit of the bone defect. General, oncologic, and functional outcomes, implant status, and complications were retrospectively analyzed. The Visual Analog Scale (VAS) was used to assess pain and the Musculoskeletal Tumor Society (MSTS) score was used to assess hip function. Osseointegration was assessed by CT. Results: According to the preoperative design, complete resection of the entire tumor and reconstruction with a custom 3D-printed sacroiliac joint implant was completed without perioperative severe complications or deaths. Relatively satisfactory surgical margins were achieved. The mean operative time and intraoperative blood loss were 495min (420-600min) and 2533.33mL (range, 1,200-3,500mL), respectively. The mean follow-up was 49.83months (range, 18-75months). At the last follow-up, all four patients were disease-free, and the two patients who developed lung metastases were alive with tumors. All patients could walk unassisted. The mean VAS was 1.33 (range, 0-2). The mean MSTS score was 25.33 (range, 24-27). CT showed complete osseointegration of the implant to the ilium and sacrum. Conclusion: The 3D-printed custom prosthesis can effectively reconstruct pelvic stability after total sacroiliac joint resection with satisfactory clinical results.

Three-Dimensional Digital Technology: A Powerful Assistant for the Reconstruction of Complex Craniofacial Deformities.

Three-dimensional digital technology has been widely applied in craniofacial surgeries, particularly in conventional procedures such as facial contouring and orthognathic surgery. To some extent, the process has already been standardized. As to reconstruction surgeries of complex craniofacial deformity, however, surgical plans need to be patient-specific. Traditionally, individualized surgical treatment largely relies on the surgeon's clinical experience. The application of digital technology mainly focuses on preoperative planning and postoperative evaluation of surgical outcomes rather than intraoperative patient-specific implants or osteotomy guides. For patients with complex craniofacial deformities, requirements for accurate 3-dimensional digital technology can be much higher. This study presents a favorable surgical reconstruction of the severe craniofacial deformity using 3-dimensional digital technology, providing references for craniofacial surgeons, which could be beneficial to clinical practice and treatment efficacy.

Accuracy and influencing factors of maxillary and mandibular repositioning using pre-bent locking plates: a prospective study

In-house repositioning methods based on three-dimensional (3D)-printing technology and the use of pre-bent plates has been gaining popularity in orthognathic surgery. However, there remains room for further improvement in methods and investigations on clinical factors that affect accuracy. This single-centre, prospective study included 34 patients and aimed to evaluate the accuracy and factors influencing maxillary and mandibular repositioning using pre-bent locking plates. The plates were manually pre-bent on the 3D-printed models of the planned position, and their hole positions were scanned and reproduced intraoperatively with osteotomy guides. The accuracy of repositioning and plate-hole positioning was calculated in three axes with the set landmarks. The following clinical factors that affect repositioning accuracy were also verified: deviation of the plate-hole positioning, amount of planned movement, and amount of simulated bony interference. The median deviations of the repositioning and hole positioning between the preoperative plan and postoperative results were 0.26 mm and 0.23 mm, respectively, in the maxilla, and 0.69 mm and 0.36 mm, respectively, in the mandible, suggesting that the method was highly accurate, and the repositioning concept based on the plate hole and form matching was more effective in the maxilla. Results of the correlation test suggest that large amounts of bony interference and plate-hole positioning errors in the up/down direction could reduce mandibular repositioning accuracy.

Virtual surgical planning and mirrored, 3-dimensionally printed guides for corrective clavicle osteotomies in clavicle malunions and nonunions.

The objective of this study was to retrospectively review clinical and radiographic outcomes of patients who underwent corrective osteotomies for clavicle malunion and internal fixation for nonunion using a combination of virtual surgical planning, patient-specific 3-dimensional (3D)-printed clavicles, and 3D-printed cutting guides manufactured at the point of care. Between 2015 and 2021, 18 patients underwent corrective osteotomy for a clavicle malunion (7 shoulders) or internal fixation for a clavicle nonunion (11 shoulders). There were 11 male and 7 female individuals with an average patient age of 43.9 (range 19-76) years. All patients underwent computed tomography evaluation of both clavicles. The DICOM files were manually segmented, virtual surgical planning was performed selectively using commercially available software, and a mirrored version of the normal clavicle was 3D printed along with a 3D-printed replica of the affected clavicle. Three-dimensionally printed mirrored clavicles were used in all cases to ensure adequate restoration of the shape and length of the clavicle and to precontour fixation plates. Virtual surgical planning and 3D-printed cutting guides for osteotomy were used in 4 of 18 (22%) patients. Either cancellous or structural intercalary bone grafting was used in 15 of 18 (83%) cases. Patients were contacted postoperatively to determine clinical outcome scores. Preoperative, early postoperative, and late postoperative radiographs were reviewed to assess for union and complications. The average follow-up time was 24.9months. Radiographic evaluation at the most recent follow-up demonstrated adequate restoration of length and successful union for all shoulders. There were no complications or reoperations. Postoperative patient-reported outcomes could be obtained in 16 of 18 (88.9%) patients. At the most recent follow-up, the mean visual analog scale for pain was 2.38 points (range, 1-7), the mean shoulder American Shoulder and Elbow Surgeons score was 73.2 points (range, 25-100), and the mean Patient-Reported Outcome Measurement Information System Upper Extremity score was 26 points (range, 7-35). All (100%) the patients were satisfied with their outcome (9 very satisfied, 7 satisfied), and their mean subjective shoulder value was 73% (range, 10%-100%). However, 2 patients complained of hardware-related symptoms, and 1 patient had return of preoperative symptoms after an interim 2 years of pain relief. The use of mirrored 3D-printed clavicles combined with virtual surgical planning and patient-specific 3D guides provides a reliable technique for restoring native anatomy when performing corrective osteotomies for clavicle malunion or internal fixation for clavicle nonunion, with a high rate of satisfactory clinical and radiographic outcomes.

A Novel Orthognathic Surgery With a Half-Millimeter Accuracy for the Maxillary Positioning Using Prebent Plates and Computer-Aided Design and Manufacturing Osteotomy Guide.

This retrospective study aimed to assess the accuracy of prebent plates and computer-aided design and manufacturing osteotomy guide for orthognathic surgery. The prebent plates correspondent to the planning model were scanned with a 3-dimensional printed model for guide design and used for fixation. Forty-two patients who underwent bimaxillary orthognathic surgery using computer-aided design and manufacturing intermediate splint with the guide (guided group: 20 patients) or with conventional fixation under straight locking miniplates (SLMs) technique (SLM group: 20 patients) were analyzed. A deviation of the maxilla between the planned and postoperative positions was evaluated using computed tomography, which was taken 2 weeks before and 4 days after the surgery. The surgery time and the infraorbital nerve paranesthesia were also evaluated. The mean deviations in the mediolateral ( x ), anteroposterior ( y ), and vertical directions ( z ) were 0.25, 0.50, and 0.37mm, respectively, in the guided group, while that in the SLM group were 0.57, 0.52, and 0.82mm, respectively. There were significant differences in x and z coordinates ( P <0.001). No significant difference in the surgery duration and paranesthesia was seen, suggesting the present method offers a half-millimeter accuracy for the maxillary repositioning without increasing the risk of extending surgery duration and nerve complication.

Effectiveness of individualized 3D titanium-printed Orthognathic osteotomy guides and custom plates

BackgroundComputer-aided design/manufacturing (CAD/CAM) technology was developed to improve surgical accuracy and minimize errors in surgical planning and orthognathic surgery. However, its accurate implementation during surgery remains a challenge. Hence, we compared the accuracy and stability of conventional orthognathic surgery and the novel modalities, such as virtual simulation and three-dimensional (3D) titanium-printed customized surgical osteotomy guides and plates.MethodsThis prospective study included 12 patients who were willing to undergo orthognathic surgery. The study group consisted of patients who underwent orthognathic two-jaw surgery using 3D-printed patient-specific plates processed by selective laser melting and an osteotomy guide; orthognathic surgery was also performed by the surgeon directly bending the ready-made plate in the control group. Based on the preoperative computed tomography images and intraoral 3D scan data, a 3D virtual surgery plan was implemented in the virtual simulation module, and the surgical guide and bone fixation plate were fabricated. The accuracy and stability were evaluated by comparing the results of the preoperative virtual simulation (T0) to those at 7 days (T1) and 6 months (T2) post-surgery.ResultThe accuracy (ΔT1‒T0) and stability (ΔT2‒T1) measurements, using 11 anatomical references, both demonstrated more accurate results in the study group. The mean difference of accuracy for the study group (0.485 ± 0.280 mm) was significantly lower than in the control group (1.213 ± 0.716 mm) (P < 0.01). The mean operation time (6.83 ± 0.72 h) in the control group was longer than in the study group (5.76 ± 0.43 h) (P < 0.05).ConclusionThis prospective clinical study demonstrated the accuracy, stability, and effectiveness of using virtual preoperative simulation and patient-customized osteotomy guides and plates for orthognathic surgery.