Search Results (160)

The aim of this study was to evaluate the impact of autoclaving on the dimensional stability of surgical guides (SGs) for aesthetic crown lengthening (ACL) using different resins/printing methods. Fifty SGs for ACL were printed using five different resin/printer combinations (FL, SR, ND, KS and VC). All the SGs were scanned before (T0) and after (T1) sterilization. Autoclaving was conducted at 134 °C during 4 min. The STL files of each SG at T0 and T1 were compared with the original design (TR). Dimensional stability was measured using trueness and precision. Deviations from TR to T1 were calculated in the three space axes and by measuring the area between three reference landmarks. At T0, the FL group showed the best trueness and precision, while the SR group performed significantly worse than the other groups. At T1, all the groups except VC exhibited significant dimensional alterations compared with T0. Also, VC showed the best trueness and precision values. All the groups had a significant deviation in at least one space axis, while only the SR group exhibited significant variations from T1 to TR in the area between the reference landmarks. Most of the evaluated resin/3D printer combinations suffered significant dimensional alterations after autoclaving. Full article

Introduction: The use of 3D-printed models in surgical planning has gained traction in light of its potential to improve precision and patient outcomes. The objective of this study was to review data and provide a time and value analysis of the use of 3D printing at a National Cancer Institute (NCI)-designated comprehensive cancer center. The estimated time of surgical procedures for surgical planning was compared with the time required for procedures that did not use 3D printing. Providers who used 3D printing completed surveys, and then the results of said surveys were analyzed to assess the value of 3D printing. Materials and Methods: Electronic health records were reviewed for patients who underwent hemipelvectomies with and without 3D printing. A list of 20 observations involving 3D printing was used as a baseline sample and matched with another 20 observations that did not utilize 3D printing. Electronic health records were reviewed to obtain mean estimates of the procedure time. The data was collected and analyzed between January 2018 and April 2025. Results: The mean surgery time for procedures using 3D printing was 868 min, compared to 993 min for procedures that did not utilize 3D printing. In contrast, the median procedure times were 907.5 min for procedures using 3D printing and 945.0 min for those that did not utilize 3D printing. Most providers (85.7%) felt that using 3D-printed models or guides was important. Similarly, 80% responded that using a 3D-printed model or guide saved them time, and another 73.3% responded that after using the 3D-printed model, they were confident in their treatment plan. Conclusions: Using 3D printing for surgical cases at the comprehensive cancer center saved procedure time and added value for the surgeons. Full article

Objectives: Pelvic tumor resections demand high surgical precision to ensure clear margins while preserving function. Although patient-specific instruments (PSIs) improve osteotomy accuracy, positioning errors remain a limitation. This study evaluates the feasibility, accuracy, and usability of a novel dual-function augmented reality (AR) system for intraoperative guidance in PSI positioning and osteotomy execution using a head-mounted display (HMD). The system provides dual-function support by assisting both PSI placement and osteotomy execution. Methods: Ten fresh-frozen cadaveric hemipelves underwent AR-assisted internal hemipelvectomy, using customized 3D-printed PSIs and a new in-house AR software integrated into an HMD. Angular and translational deviations between planned and executed osteotomies were measured using postoperative CT analysis. Absolute angular errors were computed from plane normals; translational deviation was assessed as maximum error at the osteotomy corner point in both sagittal (pitch) and coronal (roll) planes. A Wilcoxon signed-rank test and Bland–Altman plots were used to assess intra-workflow cumulative error. Results: The mean absolute angular deviation was 5.11 ± 1.43°, with 86.66% of osteotomies within acceptable thresholds. Maximum pitch and roll deviations were 4.53 ± 1.32 mm and 2.79 ± 0.72 mm, respectively, with 93.33% and 100% of osteotomies meeting translational accuracy criteria. Wilcoxon analysis showed significantly lower angular error when comparing final executed planes to intermediate AR-displayed planes (p < 0.05), supporting improved PSI positioning accuracy with AR guidance. Surgeons rated the system highly (mean satisfaction ≥ 4.0) for usability and clinical utility. Conclusions: This cadaveric study confirms the feasibility and precision of an HMD-based AR system for PSI-guided pelvic osteotomies. The system demonstrated strong accuracy and high surgeon acceptance, highlighting its potential for clinical adoption in complex oncologic procedures. Full article

Successful dental implant therapy relies on accurate planning and placement, e.g., through static, computer-aided implant surgery using CAD/CAM-fabricated surgical guides. This study examined production methods’ influence on surgical guide sleeve housing geometry. A model with two edentulous spaces was digitized using intraoral scanning and CBCT, and two virtually positioned implants were planned. Ten guides per group were produced using milling (MCX5), DLP printing (ASIGA and SHERA), and SLA printing (FORM), printing with 50 µm and 100 µm layers each. Each guide (n = 70) was then digitized using an industrial scanner before and after sterilization. Superimposition of the actual guide data with the reference data allowed for evaluation of deviations at the drill sleeve housing along the x-, y-, z-, and dxyz-axes. Descriptive and statistical evaluation was performed (significance level: p ≤ 0.0125). Significant differences existed among the production methods: Milling and SLA showed higher deviations than the DLP group (p < 0.001). Milled guides post-sterilization showed the highest deviations (0.352 ± 0.08 mm), while one DLP printer at 50 μm layer thickness showed lowest deviations (0.091 ± 0.04 mm). The layer thickness was insignificant, whereas sterilization increased deviation (p < 0.001). DLP produced the most precise implant surgical guides. All 3D printers were suitable for fabricating clinically acceptable surgical guides. Full article

Objective: This article presents a step-by-step digital technique for fabricating a 3D-printed surgical guide to assist in alveoloplasty for immediate denture placement. Methods: The workflow integrates intraoral scanning, virtual tooth extraction, digital soft tissue modeling, and additive manufacturing to produce a customized guide with an occlusal window and buccal slot, along with a verification stent. Results: This method ensures precise ridge recontouring and verification, enhancing surgical predictability and prosthetic fit. Conclusions: Unlike traditional surgical guides based on conventional casts or manual fabrication, this fully digital approach offers a practical and replicable protocol that bridges digital planning and clinical execution. By improving surgical precision, reducing operative time, and ensuring optimal denture fit, this technique represents a significant advancement in guided pre-prosthetic surgery. Full article

Background/Objectives: Recent breakthroughs in three-dimensional (3D) printing and high-resolution imaging have opened up new possibilities in personalized medicine, surgical planning, and forensic reconstruction. This study breaks new ground by evaluating the integration of high-resolution peripheral quantitative computed tomography (HR-pQCT) with multimodal imaging and additive manufacturing to assess a chronic, infected gunshot injury in the knee joint of a red deer. This unique approach serves as a translational model for complex skeletal trauma. Methods: Multimodal imaging—including clinical CT, MRI, and HR-pQCT—was used to characterise the extent of osseous and soft tissue damage. Histopathological and molecular analyses were performed to confirm the infectious agent. HR-pQCT datasets were segmented and processed for 3D printing using PolyJet, stereolithography (SLA), and fused deposition modelling (FDM). Printed models were quantitatively benchmarked through 3D surface deviation analysis. Results: Imaging revealed comminuted fractures, cortical and trabecular degradation, and soft tissue involvement, consistent with chronic osteomyelitis. Sphingomonas sp., a bacterium that forms biofilms, was identified as the pathogen. Among the printing methods, PolyJet and SLA demonstrated the highest anatomical accuracy, whereas FDM exhibited greater geometric deviation. Conclusions: HR-pQCT-guided 3D printing provides a powerful tool for the anatomical visualisation and quantitative assessment of complex bone pathology. This approach not only enhances diagnostic precision but also supports applications in surgical rehearsal and forensic analysis. It illustrates the potential of digital imaging and additive manufacturing to advance orthopaedic and trauma care, inspiring future research and applications in the field. Full article

Background: The aim of this retrospective study was to conduct an in vivo evaluation of the accuracy of surgical guides obtained via 3D printing technology that were used to transfer the 3D software-planned position and axis during palatal miniscrew placement. Methods: Twenty-four Caucasian subjects with permanent dentition underwent a CBCT examination to plan palatal skeletal anchorage using two miniscrews in the anterior palatal arch. A specific software function capable of identifying and displaying all CBCT scans passing through the planned miniscrew axis was used to identify the scan showing the maximum discrepancy between the planned and final miniscrew placement. The maximum insertion angle discrepancy and the maximum linear difference between the head and tip of the miniscrew were measured on the overlaid 3D STL models of the planned miniscrew position at CBCT with the final clinical position of the miniscrew. Results: Descriptive and inferential statistics were performed. On average, there was a discrepancy between the planned insertion axis and the final insertion axis of 2.95° (SD ± 1.13°), with a 10 mm miniscrew length. Conclusion: Three-dimensional I.-printed surgical guides for palatal miniscrew placement show a mean deviation of 2.95° from the planned position, indicating good but improvable accuracy in placement. Full article

Three-dimensional (3D) printing has emerged as a transformative technology in dental splint fabrication, offering significant advancements in customization, production speed, material efficiency, and patient comfort. This comprehensive review synthesizes the current literature on the clinical use, benefits, limitations, and future directions of 3D-printed dental splints across various disciplines, including prosthodontics, orthodontics, oral surgery, and restorative dentistry. Key 3D printing technologies such as stereolithography (SLA), digital light processing (DLP), and material jetting are discussed, along with the properties of contemporary photopolymer resins used in splint fabrication. Evidence indicates that while 3D-printed splints generally meet ISO standards for flexural strength and wear resistance, their mechanical properties are often 15–30% lower than those of heat-cured PMMA in head-to-head tests (flexural strength range 50–100 MPa vs. PMMA 100–130 MPa), and study-to-study variability is high. Some reports even show significantly reduced hardness and fatigue resistance in certain resins, underscoring material-specific heterogeneity. Clinical applications reviewed include occlusal stabilization for bruxism and temporomandibular disorders, surgical wafers for orthognathic procedures, orthodontic retainers, and endodontic guides. While current limitations include material aging, post-processing complexity, and variability in long-term outcomes, ongoing innovations—such as flexible resins, multi-material printing, and AI-driven design—hold promise for broader adoption. The review concludes with evidence-based clinical recommendations and identifies critical research gaps, particularly regarding long-term durability, pediatric applications, and quality control standards. This review supports the growing role of 3D printing as an efficient and versatile tool for delivering high-quality splint therapy in modern dental practice. Full article

Objectives: This pre-clinical feasibility study evaluates the accuracy of a novel augmented reality-based (AR-based) guidance technology using head-mounted displays (HMDs) for the placement of patient-specific instruments (PSIs)—also referred to as surgical guides—and osteotomy performance in pelvic tumour resections. The goal is to improve PSI placement accuracy and osteotomy execution while assessing user perception and workflow efficiency. Methods: The study was conducted on ten 3D-printed pelvic phantoms derived from CT scans of cadaveric specimens. Custom PSIs were designed and printed to guide osteotomies at the supraacetabular, symphysial, and ischial regions. An AR application was developed for the HoloLens 2 HMD to display PSI location and cutting planes. The workflow included manual supraacetabular PSI placement, AR-guided placement of the other PSIs and osteotomy execution. Postoperative CT scans were analysed to measure angular and distance errors in PSI placement and osteotomies. Task times and user feedback were also recorded. Results: The mean angular deviation for PSI placement was 2.20°, with a mean distance error of 1.19 mm (95% CI: 0.86 to 1.52 mm). Osteotomies showed an overall mean angular deviation of 3.73° compared to planned cuts, all within the predefined threshold of less than 5°. AR-assisted guidance added less than two minutes per procedure. User feedback highlighted the intuitive interface and high usability, especially for visualising cutting planes. Conclusions: Integrating AR through HMDs is a feasible and accurate method for enhancing PSI placement and osteotomy performance in pelvic tumour resections. The system provides reliable guidance even in cases of PSI failure and adds minimal time to the surgical workflow while significantly improving accuracy. Further validation in cadaveric models is needed to ensure its clinical applicability. Full article

Background/Objectives: Guided implant surgery relies on the use of surgical templates to direct osteotomy drills, but guide design may influence irrigation efficiency, hence bone overheating, a critical factor in preventing thermal necrosis. This ex vivo study compared temperature changes when drilling using two guide designs: a closed-frame (occlusive structure) and an open-frame (non-occlusive design), evaluating their clinical relevance in mitigating overheating. Methods: Sixteen pig ribs were scanned, and implant osteotomies were planned via a guided surgery software. Two 3D-printed resin templates, one with a closed-frame design and one with an open-frame design, were tested (8 ribs per group, 24 implants per group). Drilling was performed sequentially (diameter of 1.9 mm, 3.25 mm, and 4.1 mm) at 800 rpm, while bone temperatures were recorded at depths of 3 mm and 10 mm using K-type thermo§s. Results: Significantly higher temperature rises were observed with the closed-frame guide. Drilling depth had also a significant influence, with higher temperatures at 3 mm than 10 mm (p < 0.001), suggesting that cortical bone density may amplify frictional heat. No significant effect of drill diameter was detected. Conclusions: Within the limitations of this ex vivo model, the open-frame design kept the maximal temperature rise about 0.67 °C lower than the closed-frame guide (1.22 °C vs. 0.55 °C), i.e., a 2.2-fold relative reduction was observed during the most demanding drilling step. This suggests a more efficient cooling capacity, especially in dense cortical bone, which offers a potential benefit for minimizing thermal risk in guided implant procedures. Full article

Background: Resorbable biopolymers are increasingly explored for use in regenerative procedures within dental surgery. Their ability to degrade naturally, minimize surgical reinterventions, and potentially reduce immunogenicity makes them appealing in guided bone and tissue regeneration applications. However, despite these advantages, uncertainties persist regarding their comparative effectiveness and associated risks. For example, polyethylene glycol (PEG)-based membranes have shown comparable outcomes to porcine-derived collagen membranes in bone regeneration procedures, yet studies have reported a higher incidence of soft tissue healing complications associated with PEG-based materials. Similarly, while polycaprolactone (PCL) and dextrin-based hydrogels have demonstrated promising clinical handling and bone fill capabilities, their long-term performance and consistency across different anatomical sites remain under investigation. These findings highlight the need for further well-powered clinical trials to establish standardized guidelines for their safe and effective use. Methods: A systematic review protocol was registered with the PROSPERO database and developed in alignment with PRISMA guidelines. Database searches were conducted in PubMed, Medline, Scopus, and Cochrane from June to December 2024. Only randomized controlled trials (RCTs) focusing on synthetic resorbable biopolymers in bone augmentation procedures were considered. Bias was evaluated using the Cochrane Risk of Bias tool. Results: Eleven RCTs were included, totaling 188 patients. The findings suggest that materials such as polylactic acid (PLA), polycaprolactone (PCL), and polyethylene glycol (PEG) contributed effectively to new bone formation. PEG-based membranes were found to perform on par with or occasionally better than traditional collagen membranes derived from porcine sources. Additionally, the application of 3D-printable polymers demonstrated promise in site-specific healing. Conclusions: Resorbable biopolymers are effective and safe for GBR procedures, with clinical outcomes comparable to traditional materials. Advances in 3D-printing technology and bioactive coatings may further enhance their regenerative potential. However, the incidence of soft tissue healing complications suggests the need for further long-term studies to optimize material properties and clinical application. Full article

Background: Nasal reconstruction requires a balance between aesthetic and functional restoration. Recent advances in three-dimensional (3D) printing have introduced new approaches to this field, enabling precise, patient-specific interventions. This review explores the applications, benefits, and challenges of integrating 3D printing in nasal reconstruction. Methods: A literature search was conducted using PubMed, Scopus, and Web of Science to identify studies on 3D printing in nasal reconstruction. Peer-reviewed articles and clinical trials were analyzed to assess the impact of 3D-printed models, implants, and bioengineered scaffolds. Results: 3D printing facilitates the creation of anatomical models, surgical guides, and implants, enhancing surgical precision and patient outcomes. Techniques such as stereolithography (SLA) and selective laser sintering (SLS) enable high-resolution, biocompatible constructs using materials like polylactic acid, titanium, and hydroxyapatite. Computational fluid dynamics (CFD) tools improve surgical planning by optimizing nasal airflow. Studies show that 3D-printed guides reduce operative time and improve symmetry. Emerging bioprinting techniques integrating autologous cells offer promise for tissue regeneration. Challenges and Future Directions: Challenges include high costs, imaging limitations, regulatory hurdles, and limited vascularization in bioprinted constructs. Future research should focus on integrating bioactive materials, artificial intelligence-assisted design, and regulatory standardization. Conclusions: 3D printing offers specific advantages in nasal reconstruction, improving precision and outcomes in selected cases. Addressing current limitations through technological and regulatory advancements will further its clinical integration, potentially enhancing reconstructive surgery techniques. Full article

Objective: Trauma is a leading cause of enophthalmos, typically resulting from an increase in the volume of the bony orbit. The general consensus is that post-traumatic primary deformity repair should aim to restore the premorbid volume, shape, and cosmesis of the orbitozygomatic complex (OZC). This study aims to utilise novel three-dimensional (3D) printed patient-specific moulds to intraoperatively fabricate enophthalmos wedges and onlays using polymethylmethacrylate (PMMA) bone cement to reconstruct the OZC. Methods: A total of seven patients underwent digital surgical planning using Freeform software to virtually correct orbitozygomatic complex deformities guided by a design algorithm. Three-dimensionally printed nylon patient-specific moulds were used intraoperatively to fabricate enophthalmos wedges and/or onlays using an industry-standard PMMA bone cement. Clinical examination and application of the proposed design algorithm determined that enophthalmos wedges were indicated for four patients, with one also requiring an onlay; and periorbital onlays were required for the three remaining patients. Results: Hertel exophthalmometry at a mean follow-up of 19.1 months demonstrated good outcomes in the correction of post-traumatic enophthalmos and hypoglobus and with patients reporting good subjective cosmetic results. Patients 5 and 7 had follow-up three-dimensional computed tomography (3D-CT) to confirm correct placement. Conclusion: The use of patient-specific PMMA wedges and onlays, fabricated intraoperatively with the aid of 3D-printed moulds, offers a reliable and effective approach for correcting post-traumatic enophthalmos and hypoglobus. This method allows for the restoration of orbital volume and anatomical contours, addressing both functional and aesthetic concerns. Our results demonstrate that this technique yields favourable outcomes. Full article

Objective: Frontal sinus surgery is still challenging for surgeons; the frontal osteotomy with the preparation of a frontal bone flap to access the sinus is usually hand-crafted by experienced surgeons. The objective of our study is to present a fully digital protocol for the manufacturing of “in-house” surgical cutting guides, customized to the patient’s anatomy, to perform precise frontal sinus osteotomy, showing the costs, times, and intraoperative complications reduction. Materials and Methods: A prospective study was conducted on 12 patients with complex pathologies involving the frontal sinus who underwent frontal sinus osteotomy in the Maxillofacial Surgery Unit of the Federico II University of Naples, from January 2021 to April 2025, considering the last surgery in November 2023. The same digital protocol to manufacture the surgical cutting guide was used for all the 12 patients. The first step was to upload the preoperative CT images in DICOM format to the software Mimics Medical to perform a rapid segmentation of the skull region of interest to create a 3D object and to identify the frontal sinus margins and the osteotomy lines. The second step was to realize the surgical cutting guide, incorporating the design of titanium plates to fix onto the skull in order to make a precise osteotomy. The final digital step was to export the cutting guide 3D object in the software “Formlab-Form 3B” to print the model with a specific resin. The model was then used during the surgery to perform the precise frontal osteotomy by piezo surgery. The clinical outcomes, in terms of complications and recurrences, were then recorded. Results: In all the patients, no intraoperative complications occurred; the median follow-up was 31.7 months and at one year of follow-up only one patient experienced a recurrence. The mean operative time was about 4 h, with a frontal osteotomy time of about 23 min. Digital protocol time was about 4 h while printing times were between 2 and 4 h. Conclusions: This “in-house” protocol seems to demonstrate that the use of intraoperative templates for the realization of the frontal sinus osteotomy reduces preoperative and intraoperative costs and times, reducing the risk of intraoperative complications, and also allows less experienced surgeons to perform the procedure safely. Obviously, this study is to be considered a “pilot study”, and other studies with large cohorts of patients will have to confirm these promising results. Full article

Temporomandibular joint (TMJ) ankylosis compromises essential functions such as chewing, phonation, and breathing. Surgical treatment aims to restore mandibular mobility and prevent the recurrence of joint fusion. This article describes a technical variation based on Puricelli biconvex arthroplasty, using surgical cement, screw fixation, and 3D-printed cutting guides based on virtual planning, allowing for greater precision in joint reconstruction. In this work, we present the step-by-step process used in the customization of cutting guides, virtual planning, and the production of the interposition material with PMMA associated with fixation with titanium screws as a hybrid method for the treatment of recurrent TMJ ankylosis. This reported technique is demonstrated to be reproducible, low-cost, and effective. Full article