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The aim of this study was to investigate how precisely implantation can be realized by participants on a phantom head according to preliminary planning. Of particular interest here was the influence of participants’ previous knowledge and surgical experience on the precision of the implant placement. The placed implants were scanned using an intraoral scanner, saved as STL files, and superimposed with the 3D-planned implant placement. Deviations from the planning were indicated in millimeters and degrees. We were able to show that on average, the deviations from computer-assisted 3D planning were less than 1 mm for implantologists, and the students also did not deviate more than 1.78 mm on average from 3D planning. This study shows that guided implantology provides predictable and reproducible results in dental implantology. Incorrect positioning, injuries to anatomical structures, and implant positions that cannot be prosthetically restored can thus be avoided.

As the fibula free flap became the gold standard in mandibular reconstruction that required both hard tissue and soft tissue, various methods have been sought to solve the height discrepancy between the mandible and fibula. The purpose of this paper was to propose a surgical option that combined the microvascular fibula free flap with a 3D-bioprinted, patient-specific polycaprolactone (PCL) implant as a safe and simple novel method that achieved the best functional and aesthetic results in mandibular reconstruction surgery for young patients with malignant tumors. The patient’s reconstructed mandible maintained volume symmetry without any deformation or complications for over 6 years. Computer-aided design/computer-aided manufacturing (CAD/CAM) and 3D printing technology enabled accurate and safe surgical results.

Purpose To compare the 2D and 3D positional accuracy of four guided surgical protocols using an analysis of linear and angular deviations. Methods DICOM and .STLs files obtained from a CBCT and a digital impression were superimposed with software to plan implant position. Fifty-six patients were subdivided into 4 groups: FGA group (template support [Ts]: teeth [T]; bed preparation [Bp]: fully guided [FG]; implant insertion [Ii]: 3D template [3Dt]; device [D]: manual adapter [MA], FGM group (Ts: T; Bp: FG; Ii: 3Dt; D: fully guided mounter [FGM]), PG group (Ts: T; Bp: FG; Ii: manual; D: none) and MS group (Ts: mucosa; Bp: FG; Ii: 3Dt; D: FGM). The position of 120 implants was assessed by superimposing the planned and final position recorded with a digital impression. Results In FGA group, 3D deviations were 0.92 ± 0.52 mm at the implant head and 1.14 ± 0.54 mm at the apex, and the angular deviation (ang. dev.) was 2.45 ± 1.24°. In FGM group, were 0.911 ± 0.44 mm (head) and 1.11 ± 0.54 mm (apex), and the ang. dev. was 2.73 ± 1.96°. In PG group, were 0.95 ± 0.47 mm (head) and 1.17 ± 0.488 mm (apex), and the ang. dev. was 3.71 ± 1.67°. In MS group, were 1.15 ± 0.45 mm (head) and 1.42 ± 0.45 mm (apex), and the ang. dev. was 4.19 ± 2.62°. Ang. dev. of MS group was different from the other groups (P Conclusions Guided surgery showed a sufficient accuracy.

Background One of the challenges encountered by clinicians new to implant dentistry is the determination and controlling of implant location. This study compared the accuracy of fully guided (FG) and pilot-guided (PG) static computer-assisted implant placement (sCAIP) protocols against the conventional freehand (FH) protocol for placing single anterior and posterior implants by recently introduced clinicians to implant dentistry. Material and methods Ten clinicians new to implant dentistry inserted one anterior (central incisor) and one posterior (first molar) implants per protocol in training maxillary models. The FG protocol involved drilling and implant placement through the guide, while the PG protocol controlled the pilot drilling only. The FH implant placement was completed without the aid of any guide. A total of 30 models were used, and 60 implants were inserted. The implant vertical, horizontal neck, horizontal apex, and angle deviations from planned positions were calculated. Results The FG protocol provided the most accurate implant placement in relation to horizontal neck (0.47 mm–0.52 mm), horizontal apex (0.71 mm–0.74 mm), and angle deviations (2.42o–2.61o). The vertical deviation was not significantly different among the different protocols. The PG protocol was generally similar to the FH protocol with a horizontal neck deviation of 1.01 mm–1.14 mm, horizontal apex deviation of 1.02 mm–1.35 mm, and angle deviation of 4.65o–7.79o. The FG protocol showed similarity in the accuracy of the anterior and posterior implants. There was a tendency for inferior accuracy for posterior implants compared with anterior implants for the PG and FH protocols. Conclusions In the hands of recently introduced clinicians to implant dentistry, it appears that the accuracy of the FG protocol was superior to the other protocols and was not influenced by the position of the implants. The PG and FH protocols showed inferior accuracy for posterior implants compared with anterior implants.

Introduction: Digital implant planning enables precise prosthetically-driven implant positioning using surgical guides. Surgical guides are most likely to be additively manufactured from a photopolymerizable resin und use metal sleeves for drill guidance. The production is cost intensive and the biocompatibility of resins is controversially discussed. Sleeveless surgical guides made out of polylactic acid (PLA) might represent an alternative to the current gold standard. PLA is more economic, made out of renewable resources and is thus more environmentally friendly. Due to the biocompatibility of the material, metal sleeves could possibly be dispensed with. The aim of this study is to compare surgical guides from "Fused Filament Fabrication" (FFF) using PLA and "Stereolithography" (SLA) using resin with regard to the implant accuracy. Furthermore, potential effects of additionally inserted guide sleeves and the impact of the implant region was assessed. Methods: A planning software was used to design a surgical guide with (H) and without (OH) metal sleeves for the placement of two implants in a mandibular resin model in the region of the second premolar and molar. Each dataset was additively manufactured by SLA or FFF, yielding four groups (SLA-H, SLA-OH, FFF-H, FFF OH). After sterilizing the surgical guides of each group (n=10) a series of 80 two-piece titanium implants were placed in the mandibular model. Scan bodies were screwed on the implants and digitized using a desktop scanner. Horizontal and vertical deviations were evaluated at the apex and shoulder level, as well as main axis aberration. Regarding the statistical analysis a one way MANOVA with post-hoc Tukey-HSD was performed. Results: Guided implant insertion resulted in a maximum lateral deviation of 0.97 mm at the apex and 0.55 mm at the shoulder. Vertical deviations with a maximum of 0.56 mm at the apex and 0.24 mm at the implant shoulder were measured. Maximum axial deviation did not exceed 3.02°. Between all groups, no statistically significant difference regarding the vertical position of the implant was found (p ≤ .054). For sagittal deviations at the implant shoulder FFF-groups showed higher deviations (p ≤ .033) to SLA-groups, though no differences in the transversal dimension was measured (p ≤ .054). Insertion of a metal sleeve had no significant effect on sagittal, vertical or axial accuracy but resulted in increased transversal deviations (p = .001). Conclusion: Within the limits of this in-vitro setup, all inserted implants obtained maximum deviations of less than 1 mm, both laterally and vertically, and might therefore be acknowledged suitable for clinical application. PLA showed no significant difference in terms of implant accuracy compared to the gold standard SLA. The insertion of metal sleeves did not improve the accuracy of the implant surgery in-vitro. The experimentally used biopolymer-based PLA guides were cheaper to produce, time-effective, and potentially biodegradable., Einleitung: Bohrschablonen ermöglichen eine geführte, prothetisch orientierte Insertion dentaler Implantate. Der Fertigungsprozess erfolgt meist additiv aus photopolymerisierbaren Kunststoffen. Metallische Hülsen ermöglichen die Führung des Bohrers und verhindern den Abrieb des Schablonenmaterials. Eine Alternative zum jetzigen Goldstandard könnten Bohrschablonen aus Polylactid (PLA) darstellen, aufgrund der Bioverträglichkeit des Materials könnte möglicherweise auf die Insertion metallischer Führungshülsen verzichtet werden. Ziel der Studie ist es, Bohrschablonen zur geführten Implantatinsertion der Fertigungsverfahren Fused Filament Fabrication (FFF) und Stereolithographie (SLA) hinsichtlich der Implantatposition zu vergleichen. Die Bohrschablonenmaterialien waren PLA im FFF Verfahren und ein photopolymerisierbares Harz im SLA Verfahren. Auch der potentielle Nutzen von Führungshülsen und der Einfluss der Implantatregion wurde untersucht. Methodik: In einer Planungssoftware wurde eine virtuelle Bohrschablone mit (H) und ohne Führungshülsen (OH) zur Insertion zweier Implantate in ein Kunststoffmodell erstellt. Mithilfe der Datensätze wurden jeweils zehn Bohrschablonen für die vier Gruppen (SLA H, SLA-OH, FFF-H, FFF-OH) im SLA und FFF Verfahren hergestellt und sterilisiert. In Regio 35 und 37 wurden 80 Titan-Implantate inseriert. Die Digitalisierung der Modelle erfolgte durch einen Desktopscanner. Sowohl laterale und vertikale Abweichungen am Apex und der Implantatschulter als auch Abweichungen der Implantatachse wurden mithilfe einer Messsoftware ausgewertet. Die statistische Auswertung erfolgte anhand der MANOVA mit Post-hoc Tukey´s honest significant difference (HSD) Paarvergleichen. Ergebnisse: Die Implantate zeigten maximale laterale Abweichungen von 0,97 mm am Apex und 0,55 mm auf Höhe der Implantatschulter, vertikale Abweichungen betrugen am Apex maximal 0,56 mm und 0,24 mm an der Schulter. Es wurde eine maximale Achsabweichung von 3,02° gemessen. Es konnte kein statistisch signifikanter Unterschied beim Vergleich der vier Gruppen in der vertikalen Dimension festgestellt werden (p ≤ 0,054). Sagittale Abweichungen waren bei der FFF Versuchsgruppe höher (p ≤ 0,033) als bei SLA, transversal wurde kein Unterschied festgestellt (p ≤ 0,054). Das Einsetzen einer Bohrhülse hatte keine signifikante Auswirkung auf die vertikale Genauigkeit der Implantate, aber resultierte in höheren transversalen Abweichungen (p = 0,001). Schlussfolgerung: Maximale laterale und vertikale Abweichungen aller inserierten Implantate lagen im Rahmen dieser in-vitro Studie unter 1 mm. Bohrschablonen aus PLA zeigten keine signifikanten Unterschiede hinsichtlich der Implantatgenauigkeit im Vergleich zum Goldstandard. Die Verwendung von metallischen Führungshülsen steigerte die Genauigkeit der inserierten Implantate in-vitro nicht. Die experimentell verwendeten bioverträglichen PLA Schablonen waren in der Herstellung preiswerter, zeitsparender, und potenziell biologisch abbaubar.

Pedicle screws are used in spinal fusion for the stabilisation of the spine through a posterior approach. In spinal deformities, such as scoliosis, pedicle screw placement is especially challenging due to vertebral rotation and landmark distortion. Conventional surgical procedures such as Free-hand screw insertion mainly rely on surgeon experience and anatomical landmarks. Image- and robot-guided pedicle screw insertion can improve placement accuracy but require exposure to ionising radiation. Studies of 3D-printed patient-specific surgical guides (PSSG) have shown similar accuracy rates and reduced intra-operative radiation. Nevertheless, the guide design and workflow of these devices present significant challenges. This manuscript presents a narrative review of the literature regarding the analysis of designs, manufacturing, and technical considerations for patient-specific screw guides (PSSG). We focus on the analysis of imaging criteria, design variables (including spinal levels, anatomical landmarks and guiding tools), manufacturing technology, 3D-printing technology and validation studies (ex vivo and in vivo). We also discuss the clinical and economic benefits of PSSGs and provide further dialogue on the limitations and requirements for better adoption of this technology in future. Compared to Free-hand pedicle screw placement, we find that PSSGs show consistently superior placement accuracies and when compared to image and robot-guided technologies, their use requires less radiation exposure, shorter operative times and economic benefits. The guides are of additional use in cases of complex spinal deformities, especially if guided technologies are not available.

Contains fulltext : 239354.pdf (Publisher’s version ) (Open Access) Due to the complex anatomical shape of the pelvis, screw placement can be challenging in acetabular fracture surgery. This study aims to assess the accuracy of screw placement using patient-specific surgical drilling guides applied to pre-contoured conventional implants in acetabular fracture surgery. CT scans were made of four human cadavers to create 3D models of each (unfractured) pelvis. Implants were pre-contoured on 3D printed pelvic models and optically scanned. Following virtual preoperative planning, surgical drilling guides were designed to fit on top of the implant and were 3D printed. The differences between the pre-planned and actual screw directions (degrees) and screw entry points (mm) were assessed from the pre- and postoperative CT-scans. The median difference between the planned and actual screw direction was 5.9° (IQR: 4-8°) for the in-plate screws and 7.6° (IQR: 6-10°) for the infra-acetabular and column screws. The median entry point differences were 3.6 (IQR: 2-5) mm for the in-plate screws and 2.6 (IQR: 2-3) mm for the infra-acetabular and column screws. No screws penetrated into the hip joint or caused soft tissue injuries. Three-dimensional preoperative planning in combination with surgical guides that envelope pre-contoured conventional implants result in accurate screw placement during acetabular fracture surgery.

Background: Zygomatic implants have been described as a therapeutic alternative for patients with severe maxillary atrophy in order to avoid bone augmentation procedures. Taking that into account, in these treatments, the key factor is the position of the implant, the virtual surgical planning (VSP) is widespread among most clinicians before surgery on the patient. However, there are no studies which evaluate the clinical relevance of these VSP. The aim of this study is to determine whether digital planning on zygomatic implants has any influence on the implant dimensions and position, even when performing conventional surgery afterwards. Results: Fourteen zygomatic implants were placed in four patients. Pre-operative and post-operative helicoidal computed tomography were performed to each patient to allow the comparison between the digital planning and the final position of implants. Tridimensional deviation (TD), mesio-distal deviation (MDD), bucco-palatine deviation (BPD), and apico-coronal deviation (ACD) were evaluated as well as angular deviation (AD). Significative differences in apical TD were observed with a mean of 6.114 ± 4.28 mm (p < 0.05). Regarding implant position, only implants placed in the area of the first right molar reported significant differences (p < 0.05) for ACD. Also, implant length larger than 45 mm showed BPD significative differences (p < 0.05). Conclusions: Zygomatic implant surgery is a complex surgical procedure, and although VSP is a useful tool which helps the clinician determine the number and the length of zygomatic implants as well as its proper position, surgical experience is still mandatory., peer-reviewed

The aim of this human cadaver study was to assess the accuracy of zygomatic/pterygoid implant placement using custom-made bone-supported laser sintered titanium templates. For this purpose, pre-surgical planning was done on computed tomography scans of each cadaver. Surgical guides were printed using direct metal laser sintering technology. Four zygomatic and two pterygoid implants were inserted in each case using the guided protocol and related tools. Post-operative computed tomography (CT) scans were obtained to evaluate deviations between the planned and inserted implants. Accuracy was measured by overlaying the real position in the post-operative CT on the virtual presurgical placement of the implant in a CT image. Descriptive and bivariate analyses of the data were performed. As a result, a total of 40 zygomatic and 20 pterygoid implants were inserted in 10 cadavers. The mean deviations between the planned and the placed zygomatic and pterygoid implants were respectively (mean ± SD): 1.69° ± 1.12° and 4.15° ± 3.53° for angular deviation. Linear distance deviations: 0.93 mm ± 1.23 mm and 1.35 mm ± 1.45 mm at platform depth, 1.35 mm ± 0.78 mm and 1.81 mm ± 1.47 mm at apical plane, 1.07 mm ± 1.47 mm and 1.22 mm ± 1.44 mm for apical depth. In conclusion, the surgical guide system showed accuracy for all the variables studied and allowed acceptable and accurate implant placement regardless of the case complexity.

Background 3D printing technology in hospitals facilitates production models such as point-of-care manufacturing. Orthopedic Surgery and Traumatology is the specialty that can most benefit from the advantages of these tools. The purpose of this study is to present the results of the integration of 3D printing technology in a Department of Orthopedic Surgery and Traumatology and to identify the productive model of the point-of-care manufacturing as a paradigm of personalized medicine. Methods Observational, descriptive, retrospective and monocentric study of a total of 623 additive manufacturing processes carried out in a Department of Orthopedic Surgery and Traumatology from November 2015 to March 2020. Variables such as product type, utility, time or materials for manufacture were analyzed. Results The areas of expertise that have performed more processes are Traumatology, Reconstructive and Orthopedic Oncology. Pre-operative planning is their primary use. Working and 3D printing hours, as well as the amount of 3D printing material used, vary according to the type of product or material delivered to perform the process. The most commonly used 3D printing material for manufacturing is polylactic acid, although biocompatible resin has been used to produce surgical guides. In addition, the hospital has worked on the co-design of customized implants with manufacturing companies. Conclusions The integration of 3D printing in a Department of Orthopedic Surgery and Traumatology allows identifying the conceptual evolution from “Do-It-Yourself” to “POC manufacturing”.

Malunions of the upper extremity can result in severe functional problems and increase the risk of osteoarthritis. The surgical reconstruction of complex malunions can be technically challenging. Recent advances in computer-assisted orthopedic surgery provide an innovative solution for complex three-dimensional (3-D) reconstructions. This study aims to evaluate the clinical applicability of 3-D computer-assisted planning and surgery for upper extremity malunions. Hence, we provide a summary of evidence on this topic and highlight recent advances in this field. Further, we provide a practical implementation of this therapeutic approach based on three cases of malunited forearm fractures treated with corrective osteotomy using preoperative three-dimensional simulation and patient-specific surgical guides. All three cases, one female (56 years old) and two males (18 and 26 years old), had painful restrictions in range of motion (ROM) due to forearm malunions and took part in clinical and radiologic assessments. Postoperative evaluation of patient outcomes showed a substantial increase in range of motion, reduction of preoperatively reported pain, and an overall improvement of patients' satisfaction. The therapeutic approach used in these cases resulted in an excellent anatomical and functional reconstruction and was assessed as precise, safe, and reliable. Based on current evidence and our results, the 3-D preoperative planning technique could be the new gold standard in the treatment of complex upper extremity malunions in the future.

Background The integration of 3D printing technology in hospitals is evolving toward production models such as point-of-care manufacturing. This study aims to present the results of the integration of 3D printing technology in a manufacturing university hospital. Methods Observational, descriptive, retrospective, and monocentric study of 907 instances of 3D printing from November 2015 to March 2020. Variables such as product type, utility, time, or manufacturing materials were analyzed. Results Orthopedic Surgery and Traumatology, Oral and Maxillofacial Surgery, and Gynecology and Obstetrics are the medical specialties that have manufactured the largest number of processes. Working and printing time, as well as the amount of printing material, is different for different types of products and input data. The most common printing material was polylactic acid, although biocompatible resin was introduced to produce surgical guides. In addition, the hospital has worked on the co-design of custom-made implants with manufacturing companies and has also participated in tissue bio-printing projects. Conclusions The integration of 3D printing in a university hospital allows identifying the conceptual evolution to “point-of-care manufacturing.”

NextDent™ Model, NextDent™ SG, and two designs; models A and B (n=5), were manufactured (DDDP, EvoDent). Trueness was evaluated by comparing values for 26 parameters with the CAD models' reference values and precision through standard deviation. The trueness and precision were higher for linear than for angle parameters. X- and Y-axes showed higher trueness than Z-axis and model B higher trueness than model A. The conclusions are; the accuracy is dependent on the design of the object. The linear precision appears to be high. The highest trueness was observed for a surgical guide polymer (NextDent™ SG). The definition of clinically relevant accuracy and acceptable production tolerance should be evaluated in future studies.

Additive manufacturing (AM) offers great design freedom that enables objects with desired unique and complex geometry and topology to be readily and cost-effectively fabricated. The overall benefits of AM are well known, such as increased material and resource efficiency, enhanced design and production flexibility, the ability to create porous structures and on-demand manufacturing. When AM is applied to medical devices, these benefits are naturally assumed. However, hard clinical evidence collected from clinical trials and studies seems to be lacking and, as a result, systematic assessment is yet difficult. In the present work, we have reviewed 23 studies on the clinical use of AM patient-specific surgical guides (PSGs) for the mandible surgeries (n = 17) and temporomandibular joint (TMJ) patient-specific implants (PSIs) (n = 6) with respect to expected clinical outcomes. It is concluded that the data published on these AM medical devices are often lacking in comprehensive evaluation of clinical outcomes. A complete set of clinical data, including those on time management, costs, clinical outcomes, range of motion, accuracy of the placement with respect to the pre-operative planning, and extra complications, as well as manufacturing data are needed to demonstrate the real benefits gained from applying AM to these medical devices and to satisfy regulatory requirements.

Individual cutting guides for the reconstruction of lower jaw defects with fibular grafts are often used. However, the application of these osteotomy tools is costly and time intensive. The aim of this study was to compare the precision of osteotomies using a 3D-printed guide with those using a universal, reusable, and more cost-efficient Multi-Use Cutting Jig (MUC-Jig). In this non-blinded experimental study, 10 cranio-maxillofacial surgeons performed four graft removals each in a randomized order using the same osteotomy angle, both proximally (sagittal cut) and distally (coronal cut), of a graft (45&deg, 30&deg, 15&deg, or 0&deg, ), first with the MUC-Jig then with the 3D-printed cutting guide. The 40 fibula transplants (Tx) of each method (n = 80) were then analyzed concerning their Tx length and osteotomy angles and compared to the original planning data. Furthermore, the surgeons&rsquo, subjective perception and the duration of the two procedures were analyzed. The mean relative length and mean relative angle deviation between the MUC-Jig (&minus, 0.08 &plusmn, 1.12 mm, &minus, 0.69&deg, &plusmn, 3.15&deg, ) and the template (0.22 &plusmn, 0.90 mm, 0.36&deg, 2.56&deg, ) group differed significantly (p = 0.002, p = &lt, 0.001), but the absolute deviations did not (p = 0.206, p = 0.980). Consequently, clinically comparable osteotomy results can be achieved with both methods, but from an economic point of view the MUC-Jig is a more cost-efficient solution.

Abstract Background In dental implant treatment, the placement position of the implant body is important. The hypothesis is that there are factors that have a greater impact than the factors that have been studied so far. Material and Methods The deviation between planned and actually placed implants was measured three-dimensionally by modified treatment evaluation method in 110 patients who underwent implant placement with guided surgery for partial edentulism. Ten factors that seemed to affect errors in placement were selected: the type of tooth, type of edentulism, distance from the remaining teeth, the type of implant, implant length, number of implants, method of guidance, the number of teeth supporting the surgical guide, number of anchor pins, and presence or absence of a reinforcement structure. The effect of each factor that corrected each confounding was calculated using multivariate analysis. Results In this study, 188 implant bodies were set to target, and the errors measurement data of the implant position were as follows: average Angle, 2.5 ± 1.6° (95% CI 2.25–2.69); Base, 0.67 ± 0.37 mm (95% CI 0.62–0.72); and Apex, 0.92 ± 0.47 mm (95% CI 0.86–0.98). As the result of multivariate analysis, larger errors were present in the partially guided group than the fully guided group. The number of teeth supporting the surgical guide significantly influenced the error in placement position. The error caused by the number of anchor pins was significantly different for the Angle. Similarly, the presence of the reinforcement structure influenced the error significantly for the Angle. Conclusions It was suggested that the smaller errors could be present by performing guided surgery with full guidance and devising the design of the guide such as the number of teeth supporting the surgical guide, the setting of the anchor pin, and the reinforcement structure.

3D printed surgical guides are used for prosthetically-driven oral implant placement. When manufacturing these guides, information regarding suitable printing techniques and materials as well as the necessity for additional, non-printed stock parts such as metal sleeves is scarce. The aim of the investigation was to determine the accuracy of a surgical workflow for oral implant placement using guides manufactured by means of fused deposition modeling (FDM) from a biodegradable and sterilizable biopolymer filament. Furthermore, the potential benefit of metal sleeve inserts should be assessed. A surgical guide was designed for the installation of two implants in the region of the second premolar (SP) and second molar (SM) in a mandibular typodont model. For two additive manufacturing techniques (stereolithography [SLA]: reference group, FDM: observational group) n = 10 surgical guides, with (S) and without (NS) metal sleeves, were used. This resulted in 4 groups of 10 samples each (SLA-S/NS, FDM-S/NS). Target and real implant positions were superimposed and compared using a dedicated software. Sagittal, transversal, and vertical discrepancies at the level of the implant shoulder, apex and regarding the main axis were determined. MANOVA with posthoc Tukey tests were performed for statistical analyses. Placed implants showed sagittal and transversal discrepancies of &lt, 1 mm, vertical discrepancies of &lt, 0.6 mm, and axial deviations of &le, 3&deg, In the vertical dimension, no differences between the four groups were measured (p &le, 0.054). In the sagittal dimension, SLA groups showed decreased deviations in the implant shoulder region compared to FDM (p &le, 0.033), whereas no differences in the transversal dimension between the groups were measured (p &le, 0.054). The use of metal sleeves did not affect axial, vertical, and sagittal accuracy, but resulted in increased transversal deviations (p = 0.001). Regarding accuracy, biopolymer-based surgical guides manufactured by means of FDM present similar accuracy than SLA. Cytotoxicity tests are necessary to confirm their biocompatibility in the oral environment.

Alloplastic replacement of the temporomandibular joint (TMJ) is the treatment of choice in cases of TMJ end-stage disease. Improvements in computer-aided design/computer-aided manufacturing (CAD/CAM) translated into the possibility ongf designi very precise TMJ prostheses based on the anatomy of each single patient. Custom-made TMJ prostheses are described in the most recent literature and provide facilitations in terms of ease of placement and accuracy. Although before the era of custom-made surgical guides, they did not play a prominent role in the field of TMJ surgery, their use has become mandatory when custom-made prostheses are used. Surgical guides, generally known also as cutting guides, allow the subcondylar bone cut to be performed according to the exact shape and size of the planned prostheses. Additionally, they allow the predrilling of fixation holes in the mandible to minimize errors in prostheses positioning. However, the design of surgical guides did not evolve over time as much as prostheses did. In this paper the authors critically analysed literature on this topic and described the improvements of surgical guides over time. Moreover, based on the findings of literature research, a new cutting guide system was developed and is proposed in this article.

Introduction Great precision is required for craniofacial surgery, and computer-aided design (CAD) methods may be used to plan surgery before it is performed. In this study, three-dimensional (3D)-printed cutting guides are used to match computer models with surgical procedures. We describe a novel method of computer-aided surgery for autologous cranioplasty that includes a new strategy for generating and using cutting guides. These guides may be used not only for osteotomies, but also for many other steps in the surgical procedure. Materials and methods Preoperatively, anatomical data were imported into a CAD package and used for virtual surgical planning (VSP). Cutting guides were designed after considering how to integrate all the surgical steps. Models of the microplates and micro-screws were also made. Surgical guides were exported and printed, and preoperative simulations using a replica of the patient's skull established the sequence of steps. The accuracy of the procedure was evaluated postoperatively using computed tomography (CT) scans. Results In every patient examined, the all-in-one surgical-guide system was able to automate the many steps in the procedure and dramatically decreased the duration of surgery. The experimental guide enhanced every phase of surgery, including excising the lesion, and harvesting, positioning, and fixing the graft. In each step, precision was enhanced and the outcome corresponded with the VSP. Conclusions The few previous reports on cutting guides used in cranioplasty generally describe the use of separate guides for dismantling and reconstruction. The ability to perform more surgical sequences using a single tool can improve surgical accuracy. Clearly there is no single perfect surgical guide; however, effective surgical-design strategies should be used to build the best approach to each procedure.

Surgical interventions for jaw reconstruction require the design and the production of surgical guides that allow the surgeon to operate quickly and accurately. In some cases, the reconstruction is performed by inserting a prothesis, thus operating exclusively on the jaw, while in other cases the reconstruction is performed by withdrawing and inserting part of the fibula in place of the original jaw bone. This project aims to develop a procedure that allows 3D modeling of the surgical guides necessary for surgical intervention. The idea is to find a surgical guide archetype, a starting shape for the surgeon so that the cutting planes can be oriented without the surgical guide having to be redesigned from scratch for every single patient. The first step of the procedure is the segmentation, performed applying the thresholding operation on the images provided by magnetic resonance MR in order to identify the region of interest (ROI). The second step is the reconstruction of the 3D model, so that a mesh is obtained from 2D images. Subsequently the mesh is post-processed and the cutting plans along which the surgeon will intervene are defined.

ResumenLa impresión 3D posibilita la traslación de una planificación virtual a modelos tangibles. El uso hospitalario de las impresoras 3D comercializadas para uso doméstico facilita la obtención de forma autónoma (do it yourself) de reproducciones realistas al mínimo coste.ObjetivoExponer nuestra metodología para la traslación clínica de la impresión 3D doméstica al campo de la Cirugía Ortopédica y Traumatología, definir sus indicaciones y aplicaciones específicas de acuerdo con la experiencia clínica.Material y métodosEstudio analítico observacional prospectivo de 63 casos intervenidos en nuestro servicio desde el año 2014, mometo desde el que la impresión 3D doméstica está incluida en el proceso asistencial. Variables como el grado de satisfacción percibida por los pacientes, la precisión, el tiempo o la exposición a radiaciones ionizantes durante la intervención son analizadas.ResultadosSe define un flujo de trabajo hasta la obtención del modelo impreso en 3D mediante el uso de programas de libre acceso e impresoras 3D domésticas, con una mejoría en todas las variables incluidas en el estudio.ConclusionesLa impresión 3D doméstica tiene numerosas aplicaciones en Cirugía Ortopédica y Traumatología. La experiencia clínica ha permitido definir un flujo de trabajo con unos resultados clínicos satisfactorios.Abstract3D printing allows translation of a virtual planning to tangible models. Domestic 3D printers in hospital facilitate obtaining autonomously («do it yourself») realistic reproductions at minimum cost.ObjectiveTo describe our methodology for clinical translation of domestic 3D printing in Orthopedic Surgery and Traumatology, define indications and specific applications according to clinical experience.Materials and methodsA prospective observational analytical study of 63 patients treated in our service from 2014 in which domestic 3D printing is included in the care process. Variables such as degree of satisfaction perceived by patients, accuracy, time or exposure to ionizing radiation during surgery are analyzed.ResultsA workflow is defined to obtaining 3D printed model using freely available programs and domestic 3D printers, and variables included in the study improved.ConclusionsDomestic 3D printing has numerous applications in Orthopedic Surgery and Traumatology. Clinical experience has allowed defining a workflow with satisfactory clinical results.

One of the possible ways to increase the accuracy of bone fragments reposition in patients with condylar head fractures (CHF’s) is the use of computer diagnostics, virtual simulation of surgery, intraoperative navigation and CAD/CAM technology. The aim of present study was to evaluate the accura cy of repositioning of bone fragments in patient with CHF’s using specific fixators, navigation and repositioning guides in comparison with traditional methods of osteosynthesis according to multislice computed tomography. The patients were divided into two groups according to the type of surgery. At the first group patients were treated with the use of traditional technique and the second group – with the use of CAD/CAM technology. In all cases a 3D comparison was performed and deviations between the virtually planned and actual postoperative position of the condylar head were evaluated based on the CT data. The outer surfaces of both models (virtually planed and actual postoperative position) were selected for comparison. It was found that the average deviation between points at the 3D models obtained from postoperative CT and virtual plan was 1.02±0.56 mm at the first group and 1.05±0.46 mm in group with the use of CAD/CAM technology (p>0.05). The maximum deviations in the second group ranged from 1.4 to 4.2 average 3.3±0.87 mm. In the first group, this number were probably larger (U, p

International audience; Three-dimensional (3D) printing is booming in the medical field. This technology increases the possibilities of personalized treatment for patients, while lowering manufacturing costs. To facilitate mandibular reconstruction with fibula free flap, some companies propose cutting guides obtained by CT-guided moulding. However, these guides are prohibitively expensive (€2,000 to €6,000). Based on a partnership with the CNRS, engineering students and a biomedical company, the authors have developed cutting guides and 3D-printed mandible templates, deliverable in 7days and at a lower cost. The novelty of this project is the speed of product development at a significantly lower price. In this technical note, the authors describe the logistic chain of production of mandible templates and cutting guides, as well as the results obtained. The goal is to allow access to this technology to all patients in the near future.

Objectives: The purpose of this study was to assess the accuracy of computer-assisted implant insertion based on computed tomography and template-guided implant placement. Material and methods: A total of 246 implants were placed with the aid of 3D-based transfer templates in 181 consecutive partially edentulous patients. Five groups were formed on the basis of different implant systems, surgical protocols and guide sleeves. After virtual implant planning with the CoDiagnostiX Software, surgical guides were fabricated in a dental laboratory. After implant insertion, the actual implant position was registered intraoperatively and transferred to a model cast. Deviations between the preoperative plan and postoperative implant position were measured in a follow-up computed tomography of the patient’s model casts and image fusion with the preoperative computed tomography. Results: The median deviation between preoperative plan and postoperative implant position was 1.0 mm at the implant shoulder and 1.4 mm at the implant apex. The median angular deviation was 3.6º. There were significantly smaller angular deviations (P=0.000) and significantly lower deviations at the apex (P=0.008) in implants placed for a single-tooth restoration than in those placed at a free-end dental arch. The location of the implant, whether in the upper or lower jaw, did not significantly affect deviations. Increasing implant length had a significant negative influence on deviations from the planned implant position. There was only one significant difference between two out of the five implant systems used. Conclusion: The data of this clinical study demonstrate the accuracy and predictable implant placement when using laboratory-fabricated surgical guides based on computed tomography., Zielsetzung: Ziel der vorliegenden klinischen Untersuchung war die Evaluation der klinischen Genauigkeit schablonengestützter Implantationen mit laborgefertigten Bohrschablonen auf Basis dreidimensionaler Bildgebung. Material und Methoden: Es wurden insgesamt 246 Implantate mit laborgefertigten Bohrschablonen auf Basis einer dreidimensionaler Bildgebung in 181 teilbezahnten Patienten inseriert. Die inserierten Implantate wurden in Abhängigkeit vom verwendeten Implantatsystem, dem chirurgischen Protokoll und den verwendeten Hülsen in fünf unterschiedliche Gruppen eingeteilt. Nach dreidimensionaler Implantatplanung mit der Software CoDiagnostiX wurden im zahntechnischen Labor Bohrschablonen hergestellt. Nach Implantatinsertion wurde die aktuelle Implantatposition intraoperativ registriert und auf ein Gipsmodell des Patienten übertagen. Durch die Bildfusion der präoperativen Implantatplanung mit der dreidimensionalen Bildgebung des Gipsmodells konnten die Abweichungen zwischen geplanter und erzielter Implantatposition berechnet werden. Ergebnisse: Der Median der Abweichungen zwischen geplanter und erreichter Implantatposition war 1 mm an der Implantatbasis und 1,4 mm an der Implantatspitze. Der Median der Achsenabweichung lag bei 3,6º. Implantate, welche in einer Schaltlücke gesetzt worden waren, zeigten statistisch signifikant kleinere Achsenabweichungen (P=0.000) und geringere Abweichungen an der Implantatspitze (P=0.008) im Vergleich zu Implantaten, welche in einer Freiendsituation inseriert wurden. Es zeigte sich keine Abhängigkeit der Genauigkeit von einer Implantation im Oberkiefer oder Unterkiefer. Die zunehmende Implantatlänge wirkte sich negativ auf die Genauigkeit der erreichten Implantatposition auf. In Abhängigkeit vom Implantatsystem ergab sich ein statistisch signifikanter Unterschied ausschließlich zwischen zwei Systemen. Schlussfolgerung: Die vorliegende klinische Untersuchung konnte die hohe Präzision und Verlässlichkeit einer schablonengeführten Implantatinsertion nach computerassistierter Planung belegen., GMS Interdisciplinary Plastic and Reconstructive Surgery DGPW; 5:Doc15

This paper describes a new protocol for mandibular reconstruction. Computer-aided design/computer-aided manufacturing (CAD/CAM) technology was used to manufacture custom-made cutting guides for tumor ablation and reconstructive plates to support fibula free flaps. CT scan data from a patient with an odontogenic keratocyst on the left mandibular ramus were elaborated to produce a virtual surgical plan of mandibular osteotomy in safe tissue for complete ramus resection. The CAD/CAM procedure was used to construct a customized surgical device composed of a cutting guide and a titanium reconstructive bone plate. The cutting guide allowed the surgeon to precisely transfer the virtual planned osteotomy into the surgical environment. The bone plate, including a custom-made anatomical condylar prosthesis, was designed using the outer surface of the healthy side of the mandible to obtain an ideal contour and avoid the bone deformities present on the side affected by the tumor. Operation time was reduced in the demolition and reconstruction phases. Functional and aesthetic outcomes allowed patients to immediately recover their usual appearance and functionality. This new protocol for mandibular reconstruction using CAD/CAM to construct custom-made guides and plates may represent a viable way to reproduce the patient’s anatomical contour, give the surgeon better procedural control, and reduce operation time.

La cirugía ortognática es una de las cirugías electivas realizadas más a menudo en cirugía maxilofacial. Su planificación debe ser minuciosa, asegurando un grado de precisión tal que el margen de error sea de menos de 1 mm. El método clásico de planificar una cirugía ortognática se basaba en una cefalometría realizada a partir de una telerradiografía de perfil. A partir de aquí se trazaba una STO (Surgical Treatment Objectives) que permitía imaginar y medir en la dirección sagital los cambios quirúgicos. Concomitantemente, la cirugía de modelos corroboraba los cambios previstos con la STO. El desarrollo de las tomografías de haz de cono (CBCT) y su posterior incorporación a nuestras respectivas clínicas ha facilitado el paso de una planificación 2D basada en radiografías convencionales de perfil y ortopantomografía, a una planificación 3D basada en CBCT. Existe más de un enfoque correcto en la planificación y tratamiento de pacientes de cirugía ortognática. Cada paciente debe ser planificado y tratado de forma personalizada, según una serie de criterios. Existen pruebas adyuvantes como el escáner de haz de cono, planificación guiada por el escáner, férulas quirúrgicas CAD-CAM, modelos 3D craneales de resina o incluso cirugía con navegación asistida por robot que pueden ser útiles para mejorar los resultados quirúrgicos y disminuir el riesgo quirúrgico. Esto puede ser especialmente importante en deformidades severas, con un crecimiento anómalo y requiriendo maniobras quirúrgicas especialmente complicadas. Además, la cirugía endoscópica y la cirugía asistida por robot para navegar, están en rápido desarrollo y pueden en casos seleccionados especialmente complejos estar justificados. El objetivo de este artículo es discernir cuando son necesarias tales herramientas en cirugía ortognática. Orthognathic surgery is one of the elective surgery most often performed in maxillofacial surgery. Their planning must be thorough, ensuring a degree of precision such that the margin of error is less than 1 mm. The classical method for planning orthognathic surgery was based on a cephalometric made from a teleradiography profile. From here outlines a STO (Surgical Treatment Objectives) allowing imagine and measured in the sagittal direction surgically changes. Concomitantly, the model surgery corroborated the expected changes with the STO. The development of cone-beam CT (CBCT) and its subsequent incorporation into our respective clinics has facilitated the transition from a 2D plan based on conventional radiographs and panoramic radiograph profile, a CBCT-based 3D planning. More than one correct approach and treatment planning for orthognathic surgery patients. Each patient should be planned and treated in a personalized way, according to a set of criteria. Evidence exists adjuvants such as cone beam scanner, scanner guided planning, splints, surgical CAD-CAM, 3D models resin or cranial surgery with robot-assisted navigation can be used to improve surgical outcomes and reduce the surgical risk. This may be especially important in severe deformities with abnormal growth and requiring particularly complex surgical procedures. In addition, endoscopic surgery and robotic-assisted surgery for navigation, are rapidly developing in selected cases may be justified particularly complex. The aim of this paper is to discern when such tools are necessary in orthognathic surgery.

Objective To evaluate the reliability and accuracy of computer-designed surgical guides in osseointegrated oral implant rehabilitation. Materials and methods Six implant rehabilitations, with a total of 17 implants, were completed with computer-designed surgical guides, performed with the master model developed by muco-compressive and muco-static impressions. In the first case, the surgical guide had exclusively mucosal support, in the second case exclusively dental support. For all six cases computer-aided surgical planning was performed by virtual analyses with 3D models obtained by dental scan DICOM data. The accuracy and stability of implant osseointegration over two years post surgery was then evaluated with clinical and radiographic examinations. Radiographic examination, performed with digital acquisitions (RVG – Radio Video graph) and parallel techniques, allowed two-dimensional feedback with a margin of linear error of 10%. Results Implant osseointegration was recorded for all the examined rehabilitations. During the clinical and radiographic post-surgical assessments, over the following two years, the peri-implant bone level was found to be stable and without appearance of any complications. The margin of error recorded between pre-operative positions assigned by virtual analysis and the post-surgical digital radiographic observations was as low as 0.2 mm. Significance Computer-guided implant surgery can be very effective in oral rehabilitations, providing an opportunity for the surgeon: (a) to avoid the necessity of muco-periosteal detachments and then (b) to perform minimally invasive interventions, whenever appropriate, with a flapless approach.

Recently, stereolithography (SL), one of the most diffused techniques in the rapid prototyping area, has been used to realize surgical guides for the corrected positioning of dental grafts. This paper presents a methodology for the design and fabrication of stereolithographic surgical guides useful in alveolar reconstruction with mandibular block bone grafts. The integration between medical imaging techniques and SL was achieved. The surgical guides built with a SL machine were used as tools for surgical operations. This methodology allowed obtaining the maximum respect of the contiguous anatomical structures, the extraction of a limited amount of bone, a remarkable reduction of the operation time, and no alteration of teeth and inferior lip sensibility. The extraction and the positioning of onlay grafts within the chin resulted to be more precise and predictable using stereolithographic surgical guides.

ResumenLa cirugía ortognática es una de las cirugías electivas realizadas más a menudo en cirugía maxilofacial. Su planificación debe ser minuciosa, asegurando un grado de precisión tal que el margen de error sea de menos de 1 mm.El método clásico de planificar una cirugía ortognática se basaba en una cefalometría realizada a partir de una telerradiografía de perfil. A partir de aquí se trazaba una STO (Surgical Treatment Objectives) que permitía imaginar y medir en la dirección sagital los cambios quirúgicos. Concomitantemente, la cirugía de modelos corroboraba los cambios previstos con la STO.El desarrollo de las tomografías de haz de cono (CBCT) y su posterior incorporación a nuestras respectivas clínicas ha facilitado el paso de una planificación 2D basada en radiografías convencionales de perfil y ortopantomografía, a una planificación 3D basada en CBCT.Existe más de un enfoque correcto en la planificación y tratamiento de pacientes de cirugía ortognática. Cada paciente debe ser planificado y tratado de forma personalizada, según una serie de criterios. Existen pruebas adyuvantes como el escáner de haz de cono, planificación guiada por el escáner, férulas quirúrgicas CAD-CAM, modelos 3D craneales de resina o incluso cirugía con navegación asistida por robot que pueden ser útiles para mejorar los resultados quirúrgicos y disminuir el riesgo quirúrgico. Esto puede ser especialmente importante en deformidades severas, con un crecimiento anómalo y requiriendo maniobras quirúrgicas especialmente complicadas. Además, la cirugía endoscópica y la cirugía asistida por robot para navegar, están en rápido desarrollo y pueden en casos seleccionados especialmente complejos estar justificados. El objetivo de este artículo es discernir cuando son necesarias tales herramientas en cirugía ortognática.AbstractOrthognathic surgery is one of the elective surgery most often performed in maxillofacial surgery. Their planning must be thorough, ensuring a degree of precision such that the margin of error is less than 1 mm.The classical method for planning orthognathic surgery was based on a cephalometric made from a teleradiography profile. From here outlines a STO (Surgical Treatment Objectives) allowing imagine and measured in the sagittal direction surgically changes. Concomitantly, the model surgery corroborated the expected changes with the STO.The development of cone-beam CT (CBCT) and its subsequent incorporation into our respective clinics has facilitated the transition from a 2D plan based on conventional radiographs and panoramic radiograph profile, a CBCT-based 3D planning.More than one correct approach and treatment planning for orthognathic surgery patients. Each patient should be planned and treated in a personalized way, according to a set of criteria. Evidence exists adjuvants such as cone beam scanner, scanner guided planning, splints, surgical CAD-CAM, 3D models resin or cranial surgery with robot-assisted navigation can be used to improve surgical outcomes and reduce the surgical risk. This may be especially important in severe deformities with abnormal growth and requiring particularly complex surgical procedures. In addition, endoscopic surgery and robotic-assisted surgery for navigation, are rapidly developing in selected cases may be justified particularly complex. The aim of this paper is to discern when such tools are necessary in orthognathic surgery.