Low-cost Method for Obtaining Medical Rapid Prototyping Using Desktop 3D printing: A Novel Technique for Mandibular Reconstruction Planning

Introduction of 3D Printing in a German Municipal Hospital-Practice Guide for CMF Surgery

Study Design

This study aimed to introduce 3D printing in a municipal hospital to improve the treatment of craniomaxillofacial patients and optimize costs and operating time. Thus we describe the implementation of low-cost in-house 3D printing to facilitate orbital- and mandible reconstruction in CMF surgery. Moreover, we address legal requirements, safety at work, fire- and data protection. Finally, we want to share our experiences using 3D printing and point out its advantages in providing better patient care.

Methods

We outline the setup of in-house 3D printing and focus on obeying German health care regulations. We based our approach on a fused deposition modeling 3D printer and free software. As proof of concept, we treated 4 cases of severe orbital trauma and 1 case of mandibular reconstruction. We printed a 3D patient-specific model for each case and adapted a titanium mesh implant, respectively, a titanium reconstruction plate before performing the surgery.

Results

Our approach reduced costs, duration of anesthesia, operating time, recovery time, and postoperative swelling and increased the revenue. Functional outcome in orbital reconstruction like eye movement and double vision, was improved compared to the conventional technique. No severe complications like loss-of-vision or surgical revision occurred. Likewise, mandibular reconstruction showed no plate loosening or plate fracture.

Conclusion

The implementation of cost-efficient 3D printing resulted in successful patient treatment with excellent outcomes. Our practice guide offers a 3D printing workflow and could be adapted to fit the needs of other specialties like neurosurgery, orthopedic surgery as well.

Point-of-Care Virtual Surgical Planning and 3D Printing in Oral and Cranio-Maxillofacial Surgery: A Narrative Review

This paper provides an overview on the use of virtual surgical planning (VSP) and point-of-care 3D printing (POC 3DP) in oral and cranio-maxillofacial (CMF) surgery based on a literature review. The authors searched PubMed, Web of Science, and Embase to find papers published between January 2015 and February 2022 in English, which describe human applications of POC 3DP in CMF surgery, resulting in 63 articles being included. The main review findings were as follows: most used clinical applications were anatomical models and cutting guides; production took place in-house or as "in-house-outsourced" workflows; the surgeon alone was involved in POC 3DP in 36 papers; the use of free versus paid planning software was balanced (50.72% vs. 49.27%); average planning time was 4.44 h; overall operating time decreased and outcomes were favorable, though evidence-based studies were limited; and finally, the heterogenous cost reports made a comprehensive financial analysis difficult. Overall, the development of in-house 3D printed devices supports CMF surgery, and encouraging results indicate that the technology has matured considerably.

CLASSIFICATION AND MANAGEMENT OF HEMIFACIAL MICROSOMIA: A LITERATURE REVIEW

Hemifacial microsomia (HFM) is the 2^nd most common craniofacial birth defect after cleft lip and palate. It is said to arise from the 1^st & 2^nd intrauterine branchial arches. HFM is believed by many experts to be congenital but not inherited as most patients afflicted have no previous family history. It also known as craniofacial microstomia with cranial involvement. The real cause is unknown but largely blamed on hemorrhage of the stapaedial artery. The phenotypic expression is variable from mild to severe involving many structures such as bone, nerve, muscular tissues and soft tissue. Facial structures commonly affected include the ears, the mouth and the mandible. Mostly unilateral but bilateral have been reported. However, not much is known about this condition in sub-Saharan Africa. Multidisciplinary team management is the general consensus for optimal care. Awareness in sub-Saharan Africa of this disorder is still evolving. This review identifies various classifications, diagnoses, investigations, treatment and timelines for management of HFM. The aim of the current review was to discuss the diverse controversies, classification, diagnosis and treatment of HFM so as to increase the understanding of this condition.

Computer guided temporomandibular joint reconstruction of Kaban III hemifacial microsomia with anotia: A case report

INTRODUCTION, Hemifacial microsomia is the second most common craniofacial congenital anomaly. It corresponds to a group of malformations ranging from minimal facial asymmetry to sever form affecting mandible, soft tissues, orbit, ear, and cranial nerves. PRESENTATION OF CASE, We present a case of 6 years old patient with Kaban class III hemifacial microsomia with anotia. Temporomandibular joint was reconstructed by costochondral graft using computer guided surgery (simulation and rapid prototyping). A computer guided soft tissue guide, mandibular, and maxillomandibular/zygomatic models were constructed using rapid prototyping technology. The customized computer guided soft tissue guide was used to localize the proper position of skin incision, the mandibular model was used for preoperative reconstruction plate bending, and the maxillomandibular/zygomatic model was used to estimate the rib graft length and position. Postoperative assessment showed proper positioning of the graft, with no complications or facial nerve affection. DISCUSSION, In this report, we introduce a new computer guided technique to estimate and identify the proper position of the temporomandibular joint graft based on patient CT. This technique eliminated the need of extended incisions with excessive dissection and provided a more accessible field for rib graft fixation, facilitating the surgical procedures. CONCLUSION, The use of computer guided surgery (simulation and rapid prototyping) for temporomandibular joint reconstruction in Kaban III hemifacial microsomia with anotia facilitates the surgical procedure, minimizes procedure time, increases precision, and reduces possible complications.

A 3-Dimensional-Printed Short-Segment Template Prototype for Mandibular Fracture Repair

IMPORTANCE

After reduction of complex mandibular fractures, contouring of the fracture plates to fixate the reduced mandibular segments can be time-consuming.

OBJECTIVE

To explore the potential application of a 3-dimensional (3-D)-printed short-segment mandibular template in the management of complex mandibular fractures.

DESIGN, SETTING, AND PARTICIPANTS

A feasibility study was performed at a tertiary academic center using maxillofacial computed tomography data of 3 patients with comminuted mandibular fractures who required preoperative planning with a perfected complete mandible model.

INTERVENTIONS

Thresholding, segmentation, and realignment of the fractured mandible were performed based on computed tomography data. Each reduced mandible design was divided to create 3-D templates for 6 fracture sites: right and left angle, body, and symphyseal/parasymphyseal. Sessions were conducted with junior otolaryngology and plastic surgery residents, during which mandibular fracture plates were contoured in a "preoperative" setting against the 3-D-printed short-segment templates, and an "intraoperative" setting against the previously manufactured, complete mandible model. The previously manufactured, complete model served as a surrogate for the intraoperative mandible with the fracture site reduced.

MAIN OUTCOMES AND MEASURES

The time for 3-D template printing, the "preoperative" (measure of the time consumed preoperatively), and "intraoperative" (measure of the time saved intraoperatively) times were recorded. Comparisons were made for cost estimates between a complete model and the 3-D-printed short-segment template. The operating room charge equivalent of the intraoperative time was also calculated.

RESULTS

Of the 3 patients whose data were used, 1 was a teenager and 2 were young adults. The total time for 3-D modeling and printing per short-segment template was less than 3 hours. The median (range) intraoperative time saved by precontouring the fracture plates was 7 (1-14), 5 (1-30), and 7 (2-15) minutes, and the operating room charge equivalents were $350.35 ($50.05-$700.70), $250 ($50.05-$1501.50), and $350.35 ($100.10-$750.75) for the angle, body, and symphyseal/parasymphyseal segments, respectively. The total cost for a single 3-D-printed template was less than $20, while that for a perfected complete model was approximately $2200.

CONCLUSIONS AND RELEVANCE

We demonstrate that patient- and site-specific 3-D-printed short-segment templates can be created within the timeframe required for mandibular fracture repair. These novel 3-D-printed templates also demonstrate cost efficiency in the preoperative planning for complex mandibular fracture management compared with perfected models and facilitate plate contouring in a similar fashion. Estimation of reduced operative room cost and time with the application of these short-segment templates warrants studies in actual patient care.

LEVEL OF EVIDENCE

NA.