Restoration of the inferomedial orbital strut using a standardized three-dimensional printing implant

Effect of Pixel Offset Adjustments for XY Plane Dimensional Compensation in Digital Light Processing 3D Printing on the Surface Trueness and Fit of Zirconia Crowns

This study aimed to evaluate the effect of pixel offset adjustments in digital light processing (DLP) three-dimensional (3D) printing on the marginal and internal fit and surface trueness of zirconia crowns. Zirconia crowns were designed using dental computer-aided design software (Dentbird; Imagoworks) and fabricated with a vat photopolymerization DLP 3D printer (TD6+; 3D Controls) under three pixel offset conditions (-1, 0, and 1). Pixel offset refers to the controlled modification of the outermost pixels in the XY plane during printing to compensate for potential dimensional inaccuracies. The marginal and internal fit was assessed using a triple-scan protocol and quantified using root mean square (RMS) values. Surface trueness was evaluated by measuring RMS, positive and negative errors between the designed and fabricated crowns. Statistical analyses included one-way ANOVA and Pearson correlation analysis (α = 0.05). The Pixel offset had a significant effect on fit accuracy and surface trueness (p < 0.05). Higher pixel offsets increased marginal discrepancies (p = 0.004), with the marginal gap exceeding 120 µm at a pixel offset of 1 (114.5 ± 14.6 µm), while a pixel offset of -1 (85.5 ± 18.6 µm) remained within acceptable limits (p = 0.003). Surface trueness worsened with increasing pixel offset, showing greater positive errors (p < 0.001). Optimizing pixel offset in DLP 3D printing is crucial to ensuring clinically acceptable zirconia crowns. Improper settings may increase marginal discrepancies and surface errors, compromising restoration accuracy.

Efficacy of absorbable vs. non-absorbable patient-specific, 3D-printed implants for the treatment of facial bone fractures: a systematic review and meta-analysis

OBJECTIVE

This systematic review and meta-analysis compares the efficacy and complication rate of absorbable versus non-absorbable 3D-printed, patient-customized, maxillofacial implants in facial trauma patients.

DATA SOURCES

A comprehensive search of four databases (PubMed, Scopus, Web of Science, and Cochrane) was conducted.

METHODS

A systematic review and single-proportion meta-analysis was conducted employing PRISMA guidelines. A comprehensive search of four databases (PubMed, Scopus, Web of Science, and Cochrane) yielded a total of 4087 results. After removing duplicates, 16 articles underwent full-text analysis, with 13 meeting the inclusion criteria. The inclusion focused on primary clinical data involving 3D-printed, patient-specific implants for facial bone fracture restorations. Exclusion criteria removed studies without full text, ongoing studies, animal studies, and studies not utilizing CAD/CAM for their implants.

RESULTS

A total of 114 patients underwent insertion of 3D-printed implants. Patients receiving non-absorbable implants had a success rate of 84% (95% CI: 74-91), with complications in 12 patients. Patients receiving absorbable implants achieved a 100% success rate (95% CI: 0-100), with zero complications.

CONCLUSION

The study suggests absorbable 3D-printed implants provide superior results with fewer complications compared to non-absorbable 3D-printed implants for the treatment of facial fractures.

CLINICAL TRIAL NUMBER

Not applicable.

Comparative effectiveness of various orbital decompression techniques in treating thyroid-associated ophthalmopathy: a systematic review and meta-analysis

BACKGROUND

In thyroid-associated ophthalmopathy (TAO), orbital decompression is a critical surgical approach for functional and aesthetic reasons. Meanwhile, the presence of surgical complications, especially the new onset of primary gaze diplopia, also influences postoperative patient satisfaction. This research investigates the effectiveness and potential risks associated with different orbital decompression in patients with TAO.

METHODS

Systematic searches were conducted to identify pertinent studies from PubMed, Embase, and the Cochrane Library databases. The search was completed on October 11, 2023. And after retrieval, the publication dates of the articles included in the analysis ranged from January 1, 2008, to February 22, 2023. The overall postoperative outcomes were determined using random-effects meta-analyses with corresponding 95% confidence intervals (CI). A network meta-analysis was performed to integrate both direct and indirect evidence. The primary outcomes were defined as the status of exophthalmos and the new onset of primary gaze diplopia.

RESULTS

From 1,538 identified records, 87 studies were selected, encompassing 5102 patients and 8,779 procedures. The studies reported varying degrees of exophthalmos reduction based on different surgical techniques: -3.46 mm (95% CI -3.76 to -3.15 mm) for fat removal orbital decompression, -4.02 mm (95% CI -5.14 to -2.89 mm) for the medial wall technique, -3.89 mm (95% CI -4.22 to -3.55 mm) for the lateral wall technique, -5.23 mm (95% CI -5.69 to -4.77 mm) for the balanced wall technique, -3.91 mm (95% CI -4.37 to -3.46 mm) for the infero-medial wall technique, and - 5.80 mm (95% CI -6.47 to -5.13 mm) for the three-wall technique. The incidence of new-onset primary gaze diplopia was reported in 31 studies involving 214 out of 2001 patients, resulting in a weighted proportion of 0.11 (95% CI 0.06-0.14). Notably, the lowest rates were associated with the lateral approach and fat removal orbital decompression, with pooled proportion (95% CI) rates of 3% (1-6) and 3% (2-4), respectively, suggesting that these two techniques may be more effective in preventing the occurrence of this complication during the postoperative period.

CONCLUSIONS

This meta-analysis establishes that orbital decompression is a beneficial and safe surgical approach. While this study enhances the evidence hierarchy for orbital decompression in treating TAO, it requires further validation through larger, prospective, and randomized studies with long-term follow-up periods.

Clinical Significance of the Inferomedial Orbital Strut in Orbital Blowout Fractures: Incidence of Symptomatic Diplopia in a Fractured vs. Intact Strut

Background/Objectives: This study aims to compare the clinical findings, particularly symptomatic diplopia, associated with an inferomedial orbital strut fracture versus intact strut and to determine the clinical significance of the inferomedial orbital strut in patients with orbital floor and medial orbital wall fractures. Methods: A 10-year retrospective observational study involving orbital blowout fracture cases was conducted in our institution. Patients with fractures of the orbital floor medial to the infraorbital groove and medial orbital wall, as seen on computed tomography (CT) scans, were included in this study. Patients with concomitant orbital rim fracture and those with old orbital fractures were excluded. Fracture of the inferomedial orbital strut was diagnosed via coronal CT images and patients were classified into those with an inferomedial orbital strut fracture and those without. Results: A total of 231 orbits from 230 patients was included in the study (fractured strut on 78 sides and intact strut on 153 sides). Approximately 2/3 of patients in both groups had the field of binocular single vision in primary position upon first examination (p = 0.717). Patients with strut fractures demonstrated only comminuted or open fractures, while those without strut fractures showed diverse fracture patterns (p < 0.001). Conclusions: Inferomedial orbital strut fracture does not automatically result in diplopia in patients with orbital blowout fractures. The integrity of the orbital periosteum plays a more essential role in hampering extraocular muscle displacement, thereby preventing symptomatic diplopia in these patients.

Towards Precision Ophthalmology: The Role of 3D Printing and Bioprinting in Oculoplastic Surgery, Retinal, Corneal, and Glaucoma Treatment

In the forefront of ophthalmic innovation, biomimetic 3D printing and bioprinting technologies are redefining patient-specific therapeutic strategies. This critical review systematically evaluates their application spectrum, spanning oculoplastic reconstruction, retinal tissue engineering, corneal transplantation, and targeted glaucoma treatments. It highlights the intricacies of these technologies, including the fundamental principles, advanced materials, and bioinks that facilitate the replication of ocular tissue architecture. The synthesis of primary studies from 2014 to 2023 provides a rigorous analysis of their evolution and current clinical implications. This review is unique in its holistic approach, juxtaposing the scientific underpinnings with clinical realities, thereby delineating the advantages over conventional modalities, and identifying translational barriers. It elucidates persistent knowledge deficits and outlines future research directions. It ultimately accentuates the imperative for multidisciplinary collaboration to enhance the clinical integration of these biotechnologies, culminating in a paradigm shift towards individualized ophthalmic care.

The Use of Functional Biomaterials in Aesthetic and Functional Restoration in Orbital Surgery

The integration of functional biomaterials in oculoplastic and orbital surgery is a pivotal area where material science and clinical practice converge. This review, encompassing primary research from 2015 to 2023, delves into the use of biomaterials in two key areas: the reconstruction of orbital floor fractures and the development of implants and prostheses for anophthalmic sockets post-eye removal. The discussion begins with an analysis of orbital floor injuries, including their pathophysiology and treatment modalities. It is noted that titanium mesh remains the gold standard for orbital floor repair due to its effectiveness. The review then examines the array of materials used for orbital implants and prostheses, highlighting the dependence on surgeon preference and experience, as there are currently no definitive guidelines. While recent innovations in biomaterials show promise, the review underscores the need for more clinical data before these new materials can be widely adopted in clinical settings. The review advocates for an interdisciplinary approach in orbital surgery, emphasizing patient-centered care and the potential of biomaterials to significantly enhance patient outcomes.

The Usefulness of the Navigation System to Reconstruct Orbital Wall Fractures Involving Inferomedial Orbital Strut

BACKGROUND

Little attention has been paid to combined orbital floor and medial wall fractures with the involvement of the inferomedial orbital strut. Managing this particular fracture can prove challenging. However, various innovative techniques have been introduced to assist with the process. Our study focuses on sharing our approach to orbital wall reconstruction using navigation guidance and titanium-reinforced porous polyethylene plates, specifically cases involving the inferomedial orbital strut. We believe that implementing a navigation system can effectively lead surgeons to the fracture site with utmost safety. Also, we hypothesized that this navigation system is beneficial to use singe fan titanium-reinforced porous polyethylene plates with orbital wall fractures involving IOS while minimizing possible complications.

METHODS

We retrospectively reviewed 131 patients with medial orbital wall and orbital floor fractures with or without combined other facial bone fractures who underwent orbital wall reconstruction by a single surgeon from May 2021 to May 2023. Amongst, we identified fourteen orbital wall fractures involving the inferomedial orbital strut. We used a subciliary incision as the only approach method for performing titanium-reinforced porous polyethylene plates for navigation-guided orbital wall reconstruction. Patients were followed up for at least three months.

RESULTS

All cases were effectively resolved using titanium-reinforced porous polyethylene plates. There were no complications during the patient's complete recovery, confirmed clinically and radiologically. Based on the serial CT results, it was discovered that implanted titanium-reinforced porous polyethylene plates successfully covered the defect.

CONCLUSION

Based on our retrospective analysis, it has been determined that among the 131 recorded cases of orbital fractures, 14 of them (or 10.7%) involved the inferomedial orbital strut. Navigation-guided reduction using titanium-reinforced porous polyethylene (TR-PPE) plates can lead to predictable, reliable, and excellent outcomes for treating orbital fractures involving the inferomedial orbital strut without complications.

3D Printing in Eye Care

Three-dimensional printing enables precise modeling of anatomical structures and has been employed in a broad range of applications across medicine. Its earliest use in eye care included orbital models for training and surgical planning, which have subsequently enabled the design of custom-fit prostheses in oculoplastic surgery. It has evolved to include the production of surgical instruments, diagnostic tools, spectacles, and devices for delivery of drug and radiation therapy. During the COVID-19 pandemic, increased demand for personal protective equipment and supply chain shortages inspired many institutions to 3D-print their own eye protection. Cataract surgery, the most common procedure performed worldwide, may someday make use of custom-printed intraocular lenses. Perhaps its most alluring potential resides in the possibility of printing tissues at a cellular level to address unmet needs in the world of corneal and retinal diseases. Early models toward this end have shown promise for engineering tissues which, while not quite ready for transplantation, can serve as a useful model for in vitro disease and therapeutic research. As more institutions incorporate in-house or outsourced 3D printing for research models and clinical care, ethical and regulatory concerns will become a greater consideration. This report highlights the uses of 3D printing in eye care by subspecialty and clinical modality, with an aim to provide a useful entry point for anyone seeking to engage with the technology in their area of interest.

Efficacy of TnR Nasal Mesh for prevention of septal perforation during septoplasty

OBJECTIVE

Septoplasty has been reported as the most common cause of the septal perforation. The interposition of the graft materials between the flaps at the site of the tear may be helpful to decrease the likelihood of septal perforation. The purpose of this study was to investigate the efficacy of TnR Nasal Mesh on the prevention of septal perforation following septoplasty.

METHODS

Among 46 patients had septal perforation after septoplasty, 35 patients were treated with TnR Nasal Mesh and 11 with autologous septal cartilage for bilateral mucosal tears at the corresponding area of the nasal septum. TnR Nasal Mesh or septal cartilage was placed between the injured mucoperichondrial flaps and confirmed in its original position at both sides under nasal endoscope. Objective endoscopic examination for septal mucosa status was evaluated between the patients who were treated with TnR Nasal Mesh or septal cartilage.

RESULTS

Twenty patients (57.1%) showed complete bilateral mucosa healing and nine (25.7%) had unilateral healing after TnR Nasal Mesh insertion. However, complete bilateral and unilateral mucosa healing was observed in 4 (36.4%) and 1 patients (9.1%) treated with septal cartilage, respectively. Complete healing rate for septal perforation was significantly higher in TnR Nasal Mesh than in septal cartilage insertion (p=0.022). None of the patients showed complications or adverse reactions after TnR Nasal Mesh or septal cartilage treatment.

CONCLUSION

TnR Nasal Mesh insertion after bilateral septal mucosal tear during septoplasty reduces permanent septal perforation without an apparent adverse effect. Therefore, TnR Nasal Mesh may be a safe and effective graft material for the prevention of septal perforation following septoplasty.