Reconstruction of large mandibular and surrounding soft-tissue defects using distraction with bone transport

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.

Reconstruction of Acquired Segmental Mandibular Defects Using Pedicled Mandibular Muscle Flap and Evaluation of Speech Function and Aesthetic Outcomes

PURPOSE

The purpose of this study was to investigate the clinical effect of pedicled mandibular osteomuscular flap in the reconstouring of repair of acquired segmental mandibular defects.

PATIENTS AND METHODS

Thirteen patients with acquired segmental mandibular defects requiring secondary repair were included into the study. Pedicled mandibular osteomuscular flap was applied with strong internal fixation to repair the mandibular defects. The patients' speech, swallowing function, and aesthetic changes were evaluated upon follow-up.

RESULTS

The flaps were viable in all patients. Average speech function score was 7.6±0.6. All patients had a drinking test rating of grade I or II with good masticatory efficiency. The postoperative self-assessment Visual Analog Scale score of appearance was 7.8±0.8.

CONCLUSIONS

Pedicled mandibular osteomuscular flap is a viable choice in the secondary repair and reconstruction of mandibular acquired segmental defects. This flap could achieve better oral function with good aesthetic results.

Reconstruction of segmental mandibular defects: Current procedures and perspectives

Background

The reconstruction of segmental mandibular defects remains a challenge for the reconstructive surgeon, from both a functional and an esthetic point of view.

Methods

This clinical review examines the different techniques currently in use for mandibular reconstruction as related to a range of etiologies, including the different bone donor sites, the alternatives to free flaps (FFs), as well as the contribution of computer‐assisted surgery. Recent progress and the perspectives in bone tissue engineering (BTE) are also discussed.

Results

Osseous FF allows reliable and satisfying outcomes. However, locoregional flap, distraction osteogenesis, or even induced membrane techniques are other potential options in less favorable cases. Obtaining an engineered bone with satisfactory mechanical properties and sufficient vascular supply requires further investigations.

Conclusions

Osseous FF procedure remains the gold standard for segmental mandible reconstruction. BTE strategies offer promising alternatives.

Use of a Non-Crosslinked Collagen Membrane During Guided Bone Regeneration Does Not Interfere With the Bone Regenerative Capacity of the Periosteum

PURPOSE

To assess whether the use of a non-crosslinked porcine collagen type I and III bi-layered membrane inter-positioned between the periosteum and a bone defect would interfere with the bone regenerative capacity of the periosteum.

MATERIALS AND METHODS

Sixty rats, each with 1 critical-size calvarial defect (CSD; diameter, 5 mm) in the parietal bone, were randomly allocated to 1 of 3 equal-size groups after CSD creation: 1) the periosteum was excised and the flap was repositioned without interposition of a membrane (no-periosteum [NP] group); 2) the flap including the periosteum was repositioned (periosteum [P] group); and 3) a non-crosslinked collagen membrane was inter-positioned between the flap, including the periosteum, and the bone defect (membrane [M] group). Micro-computed tomography, qualitative histology, immunohistochemistry, and reverse transcription real-time quantitative polymerase chain reaction were performed at 3, 7, 15, and 30 days postoperatively.

RESULTS

A markedly increased radiographic residual defect length was observed in the NP group compared with the P group at 30 days. The NP group also presented a smaller radiographic bone fill area than the P group at 15 and 30 days and then the M group at 30 days. The P and M groups exhibited considerably greater expression of bone morphogenetic protein-2 and osteocalcin than the NP group at 7 days; expression of transforming growth factor-β1 was considerably greater in the NP group at 15 days. Further, the P group presented considerably higher gene expression levels of Runx2 and Jagged1 at 7 days and of alkaline phosphatase at 3 and 15 days compared with the M and NP groups.

CONCLUSION

Interposition of this specific non-crosslinked collagen membrane between the periosteum and the bone defect during guided bone regeneration interferes only slightly, if at all, with the bone regenerative capacity of the periosteum.

Effect of biomechanism mine explosion on children: craniofacial injuries and management

The significant bodily violence and harm to children from blast injuries continue to be substantially caused by unexploded ordnance and improved explosive devices. Children have many unique anatomic and pathophysiologic attributes that potentially affect their susceptibility to injury. Consequently, this provides a characteristic profile to mine blast effects and projectile injuries. As a result, children's injuries inflicted on craniofacial tissues, airway compromise, hemorrhage, and brain injuries vary significantly from those inflicted on adults. In children more than adults, it is relevant that the simplest, immediate repair of maxillofacial injury is preferable to a major complex surgical approach that is significantly delayed because of availability.Twenty-one cases of mine blast/shrapnel pediatric maxillofacial injuries were selected to represent categorical varieties of a significant but unknown number of casualties treated successfully. The high number of mortality and morbidity caused by mine blast/projectile necessitates a reappraisal of pediatric craniofacial management training. "Losing a single child's life" is especially unacceptable if that loss was found to be due to the medical preparedness being inadequate or the lack of pediatric knowledge.

[Induced membrane technique in oral & maxillofacial reconstruction]

Maxillofacial defects reconstruction represents a formidable challenge to achieve both functional and aesthetic goals. To succeed, numerous parameters must be taken into account: patient's general conditions, defect's location, width and type of the defect and eventual donor sites which can provide the tissues. Routine reconstructions include bone transplantation (autologous, homologous or heterologous), implantation of biomaterials and osteogenic distraction. The advantages of these techniques are evident, but they are usually limited by their complexity in patients with bad general health. The technique of induced membranes needs to be more known in maxillofacial surgery.