Minimal invasive treatment using patient-specific template for mandibular fractures in children: "Wing-splint" by CAD/CAM technology

Can Fracture Reduction be Attempted Through a 3D-Printed Guide Template Without Maxillomandibular Fixation?

BACKGROUND

Computer-aided design and manufacturing is widely used in clinical practice. This technology may change existing methods for mandibular fracture management.

PURPOSE

The purpose of this in-vitro study was to determine if the reduction for mandibular symphysis fracture is performed without maxillomandibular fixation (MMF) using 3-dimensional (3D)-printed template.

STUDY DESIGN, SETTING, AND SAMPLE

This was an in-vitro study and had the character of a proof-of-concept study. The study was planned using the existing 20 pairs of intraoral scan and computed tomography data. The mandibular model STL file was created by merging the STL file obtained for the bimaxillary dentitions with the computed tomography DICOM file, and this was set as the original model. In the original model, STL file of fracture model of mandibular symphysis was created using computer-aided design. A template similar to a wafer or an implant guide was manufactured from restoring the own occlusion, and the mandibular fracture model was reduced and fixed using the 3D-printed template and wire, and this was set as the experimental group. The 3D coordinate system error was measured at 6 landmarks and statistically compared using scan data between models of the groups.

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLES

Reduction techniques with MMF or without MMF using guide template for mandibular fracture model.

MAIN OUTCOME VARIABLE(S)

The 3D coordinate system error (mm).

COVARIATES

The position of landmarks.

ANALYSES

The Mann-Whitney U test, student's t-test, and the Kruskal-Wallis test were used to analyze the coordinate errors between the landmarks. A P value of < .05 was considered statistically significant.

RESULTS

The 3D error value of the control and experimental group were 1.06 ± 0.63 mm (range: 0.11 to 2.92 mm) and 0.96 ± 0.48 mm (range: 0.2 to 2.95 mm), respectively. There was no statistical difference between the control and experimental group. There was a statistically significant difference in the lower 2 and lower 3 landmarks compared to the upper 1 (P = .001 and .000, respectively) before and after the reduction in the experimental group.

CONCLUSION AND RELEVANCE

This study demonstrates that the reduction using a 3D-printed guide template for the mandibular symphysis fracture could be possible even without the MMF.

Three-dimensional printing in medicine: a systematic review of pediatric applications

BACKGROUND

Three-dimensional printing (3DP) addresses distinct clinical challenges in pediatric care including: congenital variants, compact anatomy, high procedural risk, and growth over time. We hypothesized that patient-specific applications of 3DP in pediatrics could be categorized into concise, discrete categories of use.

METHODS

Terms related to "three-dimensional printing" and "pediatrics" were searched on PubMed, Scopus, Ovid MEDLINE, Cochrane CENTRAL, and Web of Science. Initial search yielded 2122 unique articles; 139 articles characterizing 508 patients met full inclusion criteria.

RESULTS

Four categories of patient-specific 3DP applications were identified: Teaching of families and medical staff (9.3%); Developing intervention strategies (33.9%); Procedural applications, including subtypes: contour models, guides, splints, and implants (43.0%); and Material manufacturing of shaping devices or prosthetics (14.0%). Procedural comparative studies found 3DP devices to be equivalent or better than conventional methods, with less operating time and fewer complications.

CONCLUSION

Patient-specific applications of Three-Dimensional Printing in Medicine can be elegantly classified into four major categories: Teaching, Developing, Procedures, and Materials, sharing the same TDPM acronym. Understanding this schema is important because it promotes further innovation and increased implementation of these devices to improve pediatric care.

IMPACT

This article classifies the pediatric applications of patient-specific three-dimensional printing. This is a first comprehensive review of patient-specific three-dimensional printing in both pediatric medical and surgical disciplines, incorporating previously described classification schema to create one unifying paradigm. Understanding these applications is important since three-dimensional printing addresses challenges that are uniquely pediatric including compact anatomy, unique congenital variants, greater procedural risk, and growth over time. We identified four classifications of patient-specific use: teaching, developing, procedural, and material uses. By classifying these applications, this review promotes understanding and incorporation of this expanding technology to improve the pediatric care.

Utilization of Virtual Surgical Planning for Surgical Splint-Assisted Comminuted Maxillomandibular Fracture Reduction and/or Fixation

Study Design

This article was a technical note.

Objective

To demonstrate the utilization of virtual surgical planning for surgical splint (VSPSS) fabrication. The VSPSS was used as an intraoperative assisting and guiding tool for reduction and/or fixation of treatment of comminuted maxillomandibular fractures.

Methods

The presented technical note showed the fabrication process that began with data acquisition and presurgical planning using virtual surgical planning (VSP). The VSPSS was designed and fabricated after the fractures were reduced digitally in VSP. In the operating room, the VSPSS was seated to guide reduction and/or allow satisfactory fixation in three different situations.

Results

Postoperative radiographs showed an acceptable reduction of the fractures. All patients had stable and repeatable occlusion postoperatively.

Conclusions

The VSPSS is a feasible tool for surgeons to assist in the comminuted maxillomandibular fracture management, decrease operating time, and improve fracture stability.

The Use of a Novel CAD-CAM Splint to Simplify Open Reduction and Internal Fixation of Mandibular Angle Fracture: A Technical Note

Mandibular angle fractures are frequently encountered as they constitute an area of weakness. Complications after open reduction and internal fixation (ORIF) of angle fractures commonly arise due to improper reduction and fixation methods that fail to counteract the dynamic muscle forces present in this region. Conventional reduction methods such as digital manipulation, intermaxillary fixation, towel clip traction, and wiring are associated with various limitations. This technical note highlights the fabrication and use of a computer-aided designing/computer-aided manufacturing-generated splint for ORIF of a superiorly displaced mandibular angle fracture. The splint consisted of 2 components: (1) a distal tooth-borne component to guide the teeth into maximum intercuspation and (2) a proximal bone-borne component to reduce the angle fracture. This composite splint facilitates simultaneous restoration of occlusion as well as reduction of mandibular angle fractures. The advantages of this technique include the following: (1) easy fabrication of splint, (2) easy and precise anatomical reduction of angle fracture, and (3) less operative time.

Feasibility of a 3D Surgical Guide Technique for Impacted Supernumerary Tooth Extraction: A Pilot Study with 3D Printed Simulation Models

This study aimed to evaluate the feasibility of a 3-dimensional (3D) planned surgical guide technique designed for impacted supernumerary teeth (STs) extraction using 3D printed simulation models. In total, 17 participants from two university hospitals were recruited. Each participant performed surgery with both the conventional and surgical guide techniques. The following parameters were evaluated: (1) The time required for ST extraction, (2) the area of the window opening, and (3) the volume of the material removed. Time required for ST extraction was 213.65 ± 167.45 sec and 114.76 ± 42.87 sec in the conventional and surgical guide techniques, respectively, with significant differences (p = 0.028). The required area of the window opening was 48.10 ± 9.44 mm2 and 45.90 ± 8.17 mm2, respectively, in the conventional and surgical guide techniques, with no significant differences (p > 0.05). The required volume of the material removed was 121.65 ± 43.69 mm3 and 99.12 ± 17.88 mm3 in the conventional and surgical guide techniques, respectively, with significant differences (p = 0.031). The 3D planned surgical guide technique was effective for impacted ST extraction. Within the limits of this study, the surgical guide technique allows us to accomplish minimally invasive surgery within a shorter duration.