The Strategy of Delayed Reconstruction of the Mandible in War Injuries

The Reconstruction of Mandible Defects in War Injuries: Systematic Review and Meta-Analysis

Study Design

Systematic Review and Meta-Analysis.

Objective

There has been an increasing trend in maxillofacial injuries associated with combat trauma. Within the maxillofacial complex, the mandible is the most likely structure to be damaged during combat. The structural deficits as a result can be reconstructed with many options. These include vascularised bone grafts (VBGs), non-vascularised bone grafts (NVBGs), alloplastic implants, reconstruction bars and distraction osteogenesis. This study aimed to determine the common modality and efficacy of mandibular reconstruction in combat trauma-related defects.

Methods

A literature search was conducted on Pubmed, Prospero, Dynamed, DARE, EMBASE, COCHRANE and BMJ databases.

Results

A total of six articles met the inclusion criteria identifying 165 patients requiring mandibular reconstruction. Non-vascularised iliac bone graft (n = 137) was the most common method followed by ileac crest bone chips harvest using Dacron urethran osteomesh tray (n = 24) and frontoparietal grafts (n = 4). Meta-analysis of five out of six trials demonstrated an overall success rate of 85% (95% CI 79-90; I2 = 59%). A total of 13% (n = 22) of reconstructions failed either completely or partially and 21% (n = 34) of patients suffered postoperative complications.

Conclusions

NVBGs are a practical, cost-effective and favourable method of war zone management of mandibular defects with success rates comparable to those reported in the civilian literature. However, general trauma principles take precedence to rule out life-threatening injuries. Due consideration of patient factors, surgical factors, and available resources are required in the first-line management of combat-related mandibular defects.

Evidence-Based Medicine for Ballistic Maxillofacial Trauma

Ballistic trauma is a serious health issue with significant costs to physical, psychosocial, economic, and societal well-being. It may be caused from firearms, explosive devices, or any other projectile forces, and is characterized by severe tissue loss and evolving tissue devitalization. This review covers mechanism, diagnosis, and management of ballistic maxillofacial trauma, specifically. Initial evaluation includes stabilization of airway, bleeding, and circulation, followed by assessment of other injuries. The overall degree of tissue damage is determined by intrinsic patient factors and extrinsic projectile factors. Management of ballistic injuries has shifted toward advocation for early operative repair with the advent of antibiotics and advanced techniques in maxillofacial reconstruction. Appropriate timing and method of reconstruction should be carefully selected on a case-by-case basis. While ballistic trauma research is limited to studies biased by institutional practices, areas for further study identified from current literature include guidelines directing timing of reconstructive surgery; thresholds for free tissue transfer; handling of retained projectiles; incidence of surgical complications; and clinical outcomes for computer-aided surgical repair of these highly destructive injuries.

Use of Kirschner wire for immediate interim reconstruction of continuity defect of mandible in resource poor setting: Our experience

Background

Reconstruction of continuity defect of mandible is challenging, and there has been a lot of advancement in this field with variety of options for restoration. However, choice often becomes restricted in resource limited settings due to lack of trained manpower, time, infrastructure, supply of graft materials, etc. In this context, we aim to test the reliability of Kirschner wire (K-wire) with adaptation of looped-end for immediate interim reconstruction of continuity defect of mandible.

Methods

Retrospectively, medical records of 10 years data were reviewed to include 22 patients who underwent immediate interim reconstruction of mandible with K-wire with looped-end adaptation for continuity defect of mandible. Data regarding patient demographic, type and length of mandibular defect, diameter of the wire and complications were recorded.

Result

Among 22 patients within a follow-up period of 1-60 months (median 7.5), complications developed in 7 (31.8%) patients. Three patients (13.6%) had major complications which required interventions, and 5 patients (22.3%) with minor complications were managed conservatively. Total wire removal in our study is only 9%, which is lowest among the reported literature, migration or extrusion through bone was nil, and overall aesthetic and functional result was good in majority except few where either wire had to be removed or got deformed.

Conclusion

Kirschner wire (K-wire) should be considered in resource limited setting as an immediate interim reconstructive method of mandible for being cheap and widely available. Our technique of looped-end adaptation results in better stabilisation leading to less removal rate, migration or extrusion.

A comparative study of three-dimensional airway changes after fibula flap reconstruction for benign and malignant tumours in the anterior mandible

Surgical treatment of tumours in the anterior mandible and surrounding tissues may result in defects which can be restored by a fibula free flap. The upper airway may change during this process. The purpose of this retrospective study was to evaluate upper airway changes after fibula free flap reconstruction. A total of 37 patients who underwent anterior mandibulectomy and fibula free flap reconstruction between 2012 and 2020 were recruited. Patients with benign and malignant tumours involving the anterior mandible were included. Spiral computed tomography was performed 1 week preoperatively, 1 week postoperatively, and at> 1 year (range 12-23 months) after surgery. Cross-sectional areas and volumes of the upper airway were measured. Data were analysed by two-way analysis of variance. The upper airway in the malignant tumour group showed an increasing trend, especially at the soft palate and tongue base levels (P < 0.01). In the benign tumour group, the upper airway showed no significant changes. The location of the minimum cross-sectional area moved downwards in both groups, and the area increased in the malignant tumour group during long-term follow-up. Upper airway obstruction is less likely to occur in the long term after surgical resection of anterior mandible malignancies and fibula free flap reconstruction.

Mandibular shape prediction model using machine learning techniques

OBJECTIVE

To create a mandibular shape prediction model using machine learning techniques and geometric morphometrics.

MATERIALS AND METHODS

Six hundred twenty-nine radiographs were used to select the most appropriate craniomaxillary variables in different craniofacial pattern classifications using a support vector machine. To obtain the three-dimensional mandibular shape, a Procrustes fit was used on 55 tomograms, in which 17 three-dimensional landmarks were digitized. A partial least square regression was employed to find the best covariation between craniomaxillary angles and the symmetric components of mandibular shape. The model was applied to a new sample of six tomograms and evaluated by the mean absolute error. Each mandible predicted was assessed using the Hausdorff distance (HDu) and a color scale. The model was also exploratively applied to six new radiographs.

RESULTS

Covariation was 88.66% with a significance of < 0.0001 explained by twelve craniomaxillary variables. Low differences between the original and predicted models were obtained, with a mean absolute error of 0.0143. The mean distance between meshes ranged from 0.0033 to 0.0059 HDu and each color scale demonstrated general similarity between the surfaces.

CONCLUSIONS

This approach offered promising results in obtaining a mandibular prediction model that enhances shape properties in an economical way and is applicable to a Latin American population. Clinical proof of this method will require further studies with larger samples.

CLINICAL RELEVANCE

This method offers a reliable, economic alternative to traditional mandibular prediction methods and is applicable to the Latin American population.

Mandibular reconstruction with autogenous non-vascularised bone graft

Background

Reconstruction of mandibular defects can be challenging because an acceptable aesthetic and functional outcome must be achieved simultaneously.

Aim

To evaluate the pattern of mandibulectomy and reconstruction materials used in the reconstruction of mandibular defects.

Materials and methods

This was a retrospective study of mandibulectomies with reconstruction in Sokoto, Nigeria between 2012 and 2016. Data such as demographics, type of tumour, type of resection and type of reconstruction materials used were extracted and stored.

Results

Fifty-two cases of mandibulectomies were done comprising 24 males and 28 females (ratio 1:1.2). Age ranged 5–80 years with mean±SD (37.8±15). Most of the cases 30 (57.7%) were on the right. There are 35 (67.3%) benign and 17 (32.7%) malignant cases. Thirty (57.7%) lateral, 16 (30.8%) condylar, 1 (1.9%) central and 5 (9.6%) combined mandibular defects were seen. Reconstruction plate alone was used in 11 (21.2%) cases, reconstruction plate with rib and tibia grafts in 16 (30.8%) cases, reconstruction plate with Iliac crest and tibia grafts in 15 (28.8%) cases. Graft length ranged from 0–20cm. There was satisfactory outcome altogether in 32 (80.0%).

Conclusion

This study has shown the types of mandibulectomies and reconstruction materials used in our centre.