Improved accuracy of hemimandibular reconstructions involving the condyle by utilizing hydroformed reconstruction plates rather than hand-bent stock plates

Comparison of reconstruction plates and miniplates in mandibular defect reconstruction with free iliac flap

OBJECTIVE

Given the increasing demand for precise and reliable reconstructive techniques in maxillofacial surgery, we try to offer valuable insights for clinicians in selecting optimal fixation methods.

MATERIALS AND METHODS

Patients were categorized into miniplate and reconstruction plate groups for accuracy and bone healing comparison. We measured gonial angle, intercondylar, intergonial and anterior-posterior distance for general accuracy and distance of segmental endpoint to the sagittal plane for partial accuracy. The bone healing rate of the two groups was compared with CT images at 3, 6 and 12 months after operation.

RESULT

Considering directional indicators, the miniplate group exhibited a wider intercondylar distance than the reconstruction plate group (p = 0.029). At 6 months postoperatively, the miniplate group demonstrated a higher bone healing rate compared to the reconstruction plate group, with no significant differences at other time points.

CONCLUSION

Over a nearly 5-year review, mandibular reconstruction with vascularized iliac bone flaps showed that reconstruction plates better maintained condylar position accuracy, while miniplates had superior bone healing rates at 6 months. No significant differences were found in other accuracy indices between the two plates.

CLINICAL RELEVANCE

Clinicians' selection of fixation plates frequently depends on personal preference rather than evidence-based criteria. This study compares the precision and postoperative osseous healing outcomes of miniplates and reconstruction plates to provide a more scientifically grounded basis for clinical decision-making.

Design and application of a novel 3D printing digital navigation template for cubitus varus deformity in children

Background

This study was aimed to assess the feasibility and efficacy of 3D printing digital template for treatment of cubitus varus deformity.

Methods

32 patients who underwent lateral closing osteotomy were evaluated between January 2018 and January 2020 in this retrospective study. Navigation templates were used in 17 cases, while conventional surgery in 15 cases. The carrying angles before and after surgery, operation time and elbow joint function were compared.

Results

Navigation templates matched well with the anatomical markers of the lateral humerus. More accurate osteotomy degrees, shorter operation time and less radiation exposure were achieved in the navigation template group (p < 0.05). At the last follow-up time, significant difference was found based on the Bellemore criteria (p = 0.0288).

Conclusions

The novel navigation template can shorten operation time, improve the lateral closing osteotomy accuracy and improve postoperative elbow joint function.

Cutting-edge patient-specific surgical plates for computer-assisted mandibular reconstruction: The art of matching structures and holes in precise surgery

Objectives

Cutting-edge patient-specific surgical plates (PSSPs) are supposed to improve the efficiency, precision, and functional outcomes of mandibular reconstruction. This study characterized the premium role of PSSPs in precise surgery and explored their working principles in computer-assisted mandibular reconstruction (CAMR).

Methods

The PSSPs-enhanced surgical precision was investigated through the model surgery and representative cases. Spatial deviations of reconstruction were characterized by comparing the reconstructed mandible with the virtually designed mandible. Working principles of PSSPs were distinguished by a review of evolving surgical techniques in CAMR.

Results

In the model surgery, spatial deviations between the virtually planned mandible and the reconstructed mandible were 1.03 ± 0.43 mm in absolute distance deviation, 1.70 ± 1.26 mm in intercondylar length, and 1.86 ± 0.91 mm in intergonial length in the study group of PSSPs, significantly smaller than in the control group of conventional prebent surgical plates. Meanwhile, in the study group, distance deviations were 0.51 ± 0.19 mm in bone-plate distance and 0.56 ± 0.28 mm in drilled screw holes, indicating the art of matching structures and holes. The PSSPs-enhanced CAMR was further demonstrated in three representative cases of mandibular reconstruction. Finally, four primary techniques of CAMR were summarized based on a review of 8,672 articles. The premium role of PSSPs was distinguished by the benefits of matching structures and holes.

Conclusions

The PSSPs-enhanced surgical precision was verified through the model surgery and demonstrated in human surgery. Compared to other surgical techniques of CAMR, PSSPs contributed to the precise surgery by the art of matching structures and holes.

Patient-centred outcomes and dental implant placement in computer-aided free flap mandibular reconstruction: a systematic review and meta-analysis

Computerised surgical planning (CSP) and computer-aided design and manufacturing (CAD/CAM) have been demonstrated to increase surgical accuracy and reduce operative time in free flap mandibular reconstruction, but evidence is lacking as to their impact on patient-centred outcomes. Implant-supported dental prostheses, however, have been associated with improved quality of life outcomes following free flap mandibular reconstruction. We aim to review reported patient-centred outcomes in mandibular reconstruction with CSP and CAD/CAM and determine whether use of these technologies is associated with higher rates of dental implant placement following free flap mandibular reconstruction. On December 20, 2020, a systematic review and meta-analysis were conducted according to PRISMA guidelines for studies reporting quality of life, functional outcomes, and rates of dental implant placement in computer-aided free flap mandibular reconstruction. A random-effects meta-analysis was performed to compare dental implant placement rates between surgeries using CSP and those using conventional freehand techniques. A total of 767 articles were screened. Nine articles reporting patient-centred outcomes and 16 articles reporting dental implant outcomes were reviewed. Of those reporting dental implant outcomes, five articles, representing a total of 302 cases, were included in the meta-analysis. Use of CSP was associated with a significant increase in the likelihood of dental implant placement, with an odds ratio of 2.70 (95% CI 1.52 to 4.79, p = 0.0007). Standardised reporting methods and controlled studies are needed to further investigate the impact of CSP and CAD/CAM technologies on functional outcomes and patient-reported quality of life in free flap mandibular reconstruction. Use of CSP and CAD/CAM technologies is associated with higher rates of dental implant placement in patients undergoing free flap mandibular reconstruction when compared to conventional freehand techniques.

The role of computer aided design/computer assisted manufacturing (CAD/CAM) and 3- dimensional printing in head and neck oncologic surgery: A review and future directions

Microvascular free flap reconstruction has remained the standard of care in reconstruction of large tissue defects following ablative head and neck oncologic surgery, especially for bony structures. Computer aided design/computer assisted manufacturing (CAD/CAM) and 3-dimensionally (3D) printed models and devices offer novel solutions for reconstruction of bony defects. Conventional free hand techniques have been enhanced using 3D printed anatomic models for reference and pre-bending of titanium reconstructive plates, which has dramatically improved intraoperative and microvascular ischemia times. Improvements led to current state of the art uses which include full virtual planning (VP), 3D printed osteotomy guides, and patient specific reconstructive plates, with advanced options incorporating dental rehabilitation and titanium bone replacements into the primary surgical plan through use of these tools. Limitations such as high costs and delays in device manufacturing may be mitigated with in house software and workflows. Future innovations still in development include printing custom prosthetics, 'bioprinting' of tissue engineered scaffolds, integration of therapeutic implants, and other possibilities as this technology continues to rapidly advance. This review summarizes the literature and serves as a summary guide to the historic, current, advanced, and future possibilities of 3D printing within head and neck oncologic surgery and bony reconstruction. This review serves as a summary guide to the historic, current, advanced, and future roles of CAD/CAM and 3D printing within the field of head and neck oncologic surgery and bony reconstruction.

Patient-Specific 3D-Printed Miniplates for Free Flap Fixation at the Mandible: A Feasibility Study

Background

This study was conducted to evaluate the feasibility, clinical outcomes, and accuracy of patient-specific 3D-printed miniplates for mandible reconstruction with fibula free flaps.

Methods

A feasibility study was conducted with 8 patients. Following virtual planning, patient-specific 1.0 mm titanium non-locking miniplates were produced via laser selective melting. 3D-printed cutting and drilling guides were used for segmental mandible resection and flap harvesting. Flap fixation was performed with two 4-hole miniplates and 2.0 mm non-locking screws (screw length 7 mm) for each intersegmental gap. Clinical follow-up was at least 6 months. Preoperative and postoperative CT/cone beam CT data were used for 3D accuracy analysis and evaluation of bone healing. Plate-related complications were monitored clinically.

Results

Patient-specific miniplate fixation of all flaps was successfully conducted (4 mono-segmental, 4 dual-segmental) with high accuracy (3.64 ± 1.18 mm) between the virtual plan and postoperative result. No technical complications were encountered intraoperatively. Osseous union occurred in all intersegmental gaps (1 partial, 18 complete) after 10 ± 2 months. No material fracture, dislocation, or plate exposure was observed.

Conclusions

Based on this pilot observational study including a limited number of patients, free flap fixation for mandibular reconstruction with patient-specific 3D-printed miniplates is feasible and associated with high accuracy, bone healing, and remote soft tissue complications.

Clinical application of individualized 3D-printed navigation template to children with cubitus varus deformity

Background

Cubitus varus deformity is a common sequela of elbow fractures in children. Cubitus varus deformity treatment is tending toward 3D correction, which is challenging for orthopedic surgeons. This study aims to explore whether individualized 3D-printed navigation templates can assist with accurate and effective corrective treatment of children with cubitus varus deformity.

Methods

Thirty-five patients were treated for cubitus varus deformity from June 2015 to April 2017, including 21 boys and 14 girls, aged 4.6–13.2 years (average, 7.5 years). Of these cases, 17 deformities were on the left side and 18 were on the right side. All were treated with wedge osteotomy of the lateral distal humerus. 3D-printed navigation templates were used in 16 cases, while traditional surgery was used in 19 cases. All patients underwent computed tomography scans before surgery. Computer software was used to analyze the measurements and design and print individualized navigation templates. The navigation templates were matched, and surgery was initially simulated. Intraoperative individualized navigation templates were used to assist with accurate osteotomy and Kirschner wire fixation. Operation times were recorded in all cases, the carrying angles before and after surgery were assessed by computer, and postoperative elbow joint function was evaluated using Bellemore criteria. All measurement data were presented as means ± SD, and Student’s t test was used to examine differences between groups. All count data between both groups were compared using the chi-square test or Fisher’s exact test analysis.

Results

All individualized navigation templates matched well with the corresponding anatomical markers and were consistent with preoperative planning, simulated surgery, and intraoperative procedures. Average operation times from clear exposure to fixed Kirschner wire were 11.69 min (9.6–13.5 min) for the individualized navigation template group and 22.89 min (17.7–26.8 min) for the traditional operation group (p < 0.001). Average differences in postoperation carrying angles between affected and healthy sides were 1.13° (0–2.0°) and 4.21° (0–7.5°), respectively (p < 0.001). Follow-up 6–12 months postoperation showed that elbow function did not differ significantly between groups using the Bellemore criteria (p > 0.05).

Conclusions

Individualized navigation templates simplify procedures, reduce operation time, and improve accuracy when used in orthopedic surgery to treat children with cubitus varus deformity.