Scholars Journal of Medical Case Reports

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1 Scholars Journal of Medical Case Reports Sch J Med Case Rep 2017; 5(11): Scholars Academic and Scientific Publishers (SAS Publishers) (An International Publisher for Academic and Scientific Resources) ISSN (Online) ISSN (Print) Application of Load Bearing Plates In Maxillofacial Trauma- When and Why? A Case Series Dr Kriti Jain 1, Dr Lekha Sharma* 2, Dr Shweta Airan 3, Dr Manish Airan 4, Dr Mohan Baliga 5 1 MDS Oral and Maxillofacial Surgery Ex-resident MCODS, Mangalore India 2 MDS Oral and Maxillofacial Surgery Ex-resident MCODS, Mangalore India 3MDS Orthodontics Ex-resident PGIMS Rohtak India 4 MDS Prosthodontics Ex- Resident BPS-GMCW, Khanpur Kalan, Sonepat India 5 MDS Oral and Maxillofacial Surgery Professor, Dept of Oral and Maxillofacial Surgery MCODS, Mangalore Manipal College of Dental Sciences, Mangalore, Manipal University, India *Corresponding author Dr Lekha Sharma Article History Received: Accepted: Published: DOI: /sjmcr Abstract: Mandibular trauma is one of the most frequently encountered situations requiring the expertise of an oral and maxillofacial surgeon. Therefore it is expected that he possess a thorough knowledge regarding the biomechanics, principles of rigid internal fixation and patterns of osteosynthesis and fracture healing. Various fixation devices and systems are presently available in our armamentarium to address the differing types of fractures of the mandible. This article discusses the indications of load bearing plates, the treatment objectives and the surgical outcomes of patients operated at our institution using these plates. Keywords: Trauma; Mandibular fractures; rigid internal fixation; load-bearing osteosynthesis INTRODUCTION The treatment of mandibular fractures has come a long way since the earliest description of management included varieties of MMF and the use of external devices. These were associated with patient discomfort, post-operative complications and prolonged treatment times. The introduction of plate osteosynthesis in maxillofacial surgery was a breakthrough. They were the result of elaborate studies which were published and clearly defined the biomechanics of the mandible. Hardware became smaller, easier to handle and extraoral incisions could be avoided. Luhr in the 1970 s described the concept of compression osteosynthesis of the mandible and incorporated the principle of axial compression in the design of a vitallium plate with eccentric holes and selfcutting screws[1]. These were associated with low rates of complications such as non-unions, malunions or pseudo arthrosis and no post-operative MMF. This was followed by the development of the so-called reconstruction plates for the treatment of severe comminuted fractures popularized by Prein et al.[2] 1987 based on the principle of load-bearing osteosynthesis. These relatively large dimensioned plates allowed little or no movement at the plate-bone interface. Increased post-operative stability allowed optimal healing with low incidence of complications and high patient acceptance. It can be safely said that the decision regarding the use of the various types of available systems lies with the operating surgeon and depends upon a number of factors such as, the age, compliance and the condition of the patient, type, location and fracture pattern or the presence of any local or systemic complications. It is imperative to recognize that fixation requirements are different for different types of fractures. Some require stability whereas others depend on compression. For the treatment of a complex comminuted fracture, the principle of load-bearing osteosynthesis is a pre requisite to ensure functional stability and good treatment outcome[3]. This paper discusses the various indications and surgical outcomes of the use of load bearing plates in complex fractures of mandible. CASE REPORTS Patients with mandibular fractures who reported to the Department of oral and maxillofacial surgery, Manipal College of Dental Sciences, Mangalore were assessed clinically and radiographically using CT scans or orthopantomograms. Those with comminuted fractures were included to be the subjects of the present study. We report the surgical Available Online: 805

2 procedure and the treatment outcome with the use of load bearing plates in patients operated within the time period between January 2013 and December Table-1: fracture location and any associated complication at the initial presentation S. no Fracture site Associated fractures/complication at presentation 1. Right parasymphysis None 2. Left angle Contralateral parasymphysis fracture 3. Left angle Infection at fracture site 4. Left Sub condylar None 5. Symphysis Panfacial; avulsed mandibular anterior dentoalveolar segment 6. Symphysis None 7. Symphysis None 8. Right Body None 9. Right angle None 10. Left parasymphysis None The patients were operated by a single maxillofacial surgeon under general anesthesia with the same unit and trainees present for all patients. Fracture site was infiltrated with local anesthetic containing vasoconstrictor. Transoral degloving incisions were used as per the location in all patients. The application of arch bars and intraoperative MMF was decided based on the status of occlusion, dentition and fracture pattern and location. This was preferred over manual reduction of displaced segments and maintaining occlusion. The teeth in line of fractures were retained unless they were absolutely indicated for extraction such as gross decay, luxation, root fracture or those that inhibit fracture reduction. Bone fragments were not removed as long as periosteal attachments were present and in general we discouraged the practice of removal of any comminuted pieces of the bone. 2.4mm Reconstruction plates (Orthomax, India) with the principle of load-bearing osteosynthesis were applied across the fracture segment at the lower border of the mandible according to the guidelines set by AO/ASIF and fixed using self-tapping bicortical screws. The MMF was released, occlusion re checked and surgical site irrigated thoroughly using betadinesaline solution. Closure was achieved using simple interrupted resorbable 3-0 Vicryl (Ethicon) sutures. A broad spectrum antibiotic was prescribed in the perioperative period for 5-6days along with a 0.2% Chlorhexidine mouthwash. Patients were allowed to consume a soft diet commencing on post-operative day 1. Instructions to maintain oral hygiene were given. Patients were comfortable in the immediate post-operative period and reported pain of mild to moderate intensity which was easily managed with Intravenous followed by oral analgesics (Inj Paracetamol 1g thrice daily and Tablet Brufen 400mg as per required). The mean length of stay at hospital was 3 days. Post-operative radiographs were obtained for all patients to assess fracture reduction. Arch bars were removed 4-6 weeks later. No post-surgical complications were encountered. Image-1: Fracture at symphysis Available Online: 806

3 Image-2: Post reduction and fixation for patient shown in Image 1 Image-3: Symphysis fracture with avulsion of dentoalveolar segment Image-4: Post reduction and fixation for patient shown in Image 3 Image-5: Fracture at angle of mandible Image-6: Load bearing plate used for rigid fixation of fracture in Image 5 Available Online: 807

4 DISCUSSION According to the AO/ASIF principles, the goal of open reduction and internal fixation (ORIF) in the management of mandibular fractures is to achieve undisturbed healing and restoration of form and function without the adjunctive use of maxillomandibular fixation (MMF)[4] The need for the open reduction of severely comminuted mandibular fractures was recognized by Kazanjian during management of facial trauma in World War I injuries[5]. Although many surgeons adopted his philosophy of ORIF, some advocated that the appropriate treatment for such severe forms of fractures required a conservative approach[6]. This school of thought was based on the idea that excessive stripping and exposing the fractured segments may result in segmental loss of bone and associated morbidity. However, due to the excellent blood supply of the head and neck in general and the face in particular; comminuted pieces of bone and fractured segments can be safely exposed and fixed using plates, screws or wires[7]. This does not lead to necrosis or loss of viability as long as they are made stable and bridged in a rigid fixation. Our practice of incorporating the 2.4mm reconstruction plates has yielded favourable results in agreement with several earlier studies such as Scolozzi and Richter [8], Ellis et al.[9] compared the incidence of post-operative complication rates and found that the patients treated with ORIF with reconstruction plates (10.3%) fared better than those treated using external pins (35.2%) or closed reduction using MMF (17.1%). In comminuted fractures, the bone fragments cannot take part in the functional loading of the mandible. In other words, load-sharing osteosynthesis between implant and bone is not possible. Therefore such complex fractures require the use of heavy plates which bear all or most of the functional stress and forces acting on the mandible. This is the key philosophy behind load-bearing osteosynthesis. Additionally, it meets the criteria for the stability principle of fracture reduction and fixation. The main proponents of which include RIF followed by early mobilization thereby avoiding post-operative complications like fracture osteitis, osteomyelitis and non-union which normally co relate with instability [2,4]. To achieve this stability, three important points have to be kept in mind; Minimum 3 screws in each main fragment for comminuted fractures If bone fragments are unstable, any type of metallic foreign body will promote resorption and infection A bone graft will heal despite previous infection if adequately immobilized The application of a RIF s device at the inferior border of the mandible is consistent with the understanding of the basic biomechanics of the mandible [10]. It has been established that the internal trabeculae of bone tend to assume a trajectorial alignment that converts the various types of imposed stress into pure tension and compression forces. In the mandible, the chief tension trajectory is at the alveolar region and the chief pressure or compression trajectory lies in the basal bone. The zero force line or the neutral zone coincides with the mandibular canal. Therefore, all functional loads are distributed along the basal and alveolar part of the mandible. Restoring disruptions in these trajectories in a fractured mandible forms the basis of RIF and imparts functional stability postoperatively. Depending on location and type of fracture, various methods may be used to achieve neutralization of the tension and compression trajectories. Tension trajectory splints, arch bars, interdental wiring (dentate) or miniplates (beyond molars). These form the tension bands and prevent splaying apart of the superior border of the mandible and dentoalveolar segments under functional loading of the bone. Pressure trajectory stabilization plate in the form of a miniplate in simple linear fractures or reconstruction load bearing plates in comminuted fractures. Following the justified application of the indicated RIF device, the pattern of bone healing that ensues is the primary or the direct bone healing in which the osseous fragments unite without the intermediate steps of tissue differentiation and callus formation. Small areas of the fracture are in direct contact with each other. In the absence of any mobility across the fracture site, the healing will be rapid and without complications. The design of a load bearing plate ensures that there is little mobility between the fracture segments or between the plate and the bone. The locking screw head-plate interface maintains a tight snug fit which prevents any micro movements or loosening of the screws, hardware failure or malunited or non-united fracture segments. Angiogenesis and neo vascularization occur unimpeded in an absolutely rigid or functionally stable environment [7,11]. A comminuted fracture of the mandible is an unforgiving surgical complication which necessitates a Available Online: 808

5 thorough knowledge of the biomechanics, principles of rigid internal fixation and patterns of osteosynthesis. A conscientious operator should strive to aim for the best treatment possible. Of course there are easier alternatives for surgical intervention, which are relatively conservative and there is no harm in putting them into practice, unless the situation at hand warrants the need for a rigid fixation with absolute stability. clinics of North America May 31;21(2): Funding None Conflict of interest None Ethical approval Not required REFERENCES 1. Luhr HG. The compression-osteosynthesis of mandibular fractures in dogs. A histologic contribution to primary bone healing. Eur Surg Res 1: 157e292, Prein J, Kellman RM. Rigid internal fixation of mandibular fractures--basics of AO technique. Otolaryngologic clinics of North America Aug;20(3): Ellis E: Rigid skeletal fixation of fractures. J Oral Maxillofac Surg 1993; 51: pp Spiessl B. Internal fixation of the mandible.a manual of AO/ASIF principles. Springer, Berlin Heidelberg New York Kazanjian VH. Immobilization of wartime, compound, comminuted fractures of the mandible. American Journal of Orthodontics and Oral Surgery Oct 1;28(10):B Finn RA. Treatment of comminuted mandibular fractures by closed reduction. Journal of oral and maxillofacial surgery Mar 1;54(3): Spiessl B. Comminuted fractures. In (eds): Internal fixation of the mandible. Berlin: Springer-Verlag, pp Scolozzi P, Richter M. Treatment of severe mandibular fractures using AO reconstruction plates. Journal of oral and maxillofacial surgery Apr 30;61(4): Ellis E, Muniz O, Anand K. Treatment considerations for comminuted mandibular fractures. Journal of oral and maxillofacial surgery Aug 31;61(8): Champy M, Lodde JP, Schmitt R, Jaeger JH, Muster D. Mandibular osteosynthesis by miniature screwed plates via a buccal approach. Journal of maxillofacial surgery Dec 31;6: Alpert B, Tiwana PS, Kushner GM. Management of comminuted fractures of the mandible. Oral and maxillofacial surgery Available Online: 809