Reconstruction of the mandible with a poly(D,L-lactide) scaffold, autogenous corticocancellous bone graft, and autogenous platelet-rich plasma: an animal experiment.

An animal study is presented, evaluating a method of mandibular reconstruction using a poly(D,Llactide) (PDLLA) scaffold. Six goats underwent a continuity resection of the mandibular angle. The defect was bridged with a preshaped PDLLA scaffold, filled with an autogenous particulate bone graft from the anterior iliac crest, and fixed with two preshaped titanium plates. To accelerate bone healing, autogenous platelet-rich plasma was mixed with the particulate bone graft. All goats had an uneventful healing. The osteosynthesis system withstood immediate loading for a period of 6 weeks until sacrifice. The particulate bone grafts within the PDLLA scaffold, which appeared to be narrowed, showed considerable resorption and replacement by fibrous tissue. In all goats, however, callus formation along the reconstructed segment was seen, providing bony continuity and maintaining the original contour of the reconstructed segment. Thus, the technique used may provide an alternative for reconstruction with revascularized composite flaps with less associated donor site morbidity.

Treatment of mandibular condylar process fractures: biological considerations.

The topic of condylar injury in adults has generated more discussion and controversy than any other in the field of maxillofacial trauma. It is an important subject because such injuries are common and complications of trauma to the temporomandibular joint (TMJ) are far-reaching in their effects. Why are there so many different methods to treat this injury? How can seemingly disparate treatment options all produce satisfactory outcomes in the majority of patients? The reason lies with the biological adaptations that occur within the masticatory system that are poorly understood, not readily quantifiable, and variable from one person to the next. This discussion presents our current understanding of the adaptations that must occur to provide the patient with a satisfactory outcome. The adaptations for patients treated open are different than for those treated closed. However, it is when these adaptations fail to occur that unsatisfactory outcomes occur, regardless of how they were treated.

TMJ fractures in children: importance of functional activation of muscles in preventing mandibular asymmetries and facial maldevelopment.

Normal development of the mandible as well as some portions of the upper jaw and face are related to good function of the masticatory apparatus: the integrity and interaction of bony and soft-tissue structures may be highly disturbed by injury of the TM joints and result in facial and occlusal disharmonies. When the neuromuscular system is in harmony, the mandibular muscles collectively exert their effect on both position and movement of the jaw and the loading of forces on the TM joints is optimal and balanced. Unfortunately, TMJ fractures may alter completely this balance with loss of the support to the mandible against the temporal component and loss of the functional effect of the lateral pterygoid muscle on the mandible. Disturbances in the harmonious interplay of the masticatory muscles may result in facial alteration and asymmetries. If not treated, the dysplastic patterns of growth continues and worsens during the years.

Segmental mandibular reconstruction by microincremental automatic distraction osteogenesis: an animal study.

We investigated the reconstruction of a surgically created critical size mandibular defect in sheep using a newly developed automatic distraction device. The device has an implantable component, which is fixed to the mandible to allow the transfer of the transport disc across the created defect, and an external component which is mounted on the activation pump and secured away from the site of bone distraction. Compression of the bellows in the external component causes fluid to be forced through the connecting tube into the distraction component. Distraction at a rate of 1 mm over 24 h was achieved in six sheep. New bone generated at the site of the created defects both anterior (compression side) and posterior (tension side) to the transport disc and had similar radiodensity to the adjacent mandibular bone eight weeks after the completion of distraction.

[The comparative efficacy of different physiotherapy combinations in treating mandibular fractures]. / Sravnitel'naia éffektivnost' razlichnykh kompleksov fizioterapii v lechenii perelomov nizhnei cheliusti.

The authors compare the efficacy of IR laser, a combination of magnetic laser radiation and UHF electric field followed dy calcium chloride electrophoresis on the course of mandibular fracture healing. With this purpose 114 patients with uni- and bilateral mandibular fractures were examined and administered a course of preventive treatment. Analysis of the clinical data, subjective sensations of the injured subjects, and data of functional diagnostic methods (rheography, polarography, echo-osteometry) brought the authors to a conclusion on a positive effect ot IR laser and, more so, of magnetic laser therapy on the recovery of regional hemodynamics and oxygen homeostasis of tissues at the site of injury, this being conducive to reduction of pyoinflammatory complications and a sooner rehabilitation of the patients. These results recommend IR laser combined with magnetic field exposure for multiple-modality treatment of patients with mandibular fractures, particularly for those with marked dislocation of bone fragments and regional blood flow disturbances.

[A method for performing stimulation electromyography of the masticatory muscles in man]. / Metodika provedeniia stimuliatsionnoi élektromiografii zhevatel'nykh myshts u cheloveka.

A principal block scheme of an apparatus complex is suggested and a method for examination of masticatory muscle function is described. The method is based on electrostimulation of masticatory nerve followed by registration and analysis of the masticatory muscle action evoked potentials. The block scheme of the apparatus complex includes a universal electrostimulator ESU-2. Examinations of 30 healthy volunteers and 30 patients with unilateral fractures of the mandible helped define the major parameters of stimulation electromyography. The patients were treated by splints applied on the teeth with fixation on both jaws. By day 28 of the investigation the M-response amplitude dropped more than twofold and its length by 1.5 times as against the mean parameters in health.