Prevalence of Plate Exposure after Mandibular Resection in Ameloblastoma Patients

Mandibular resection is a procedure to treat diseases or disorders of the mandible. Mandibulectomy is indicated for diseases involving the mandible. Plate exposure is a common postoperative complication of mandibular resection followed by reconstruction with plate fixation. Objective: This study was to obtain data regarding the number of plate exposed cases after madibular resection for indications of ameloblastoma at KSM Oral and Maxillofacial Surgery, RSUP Dr. Hasan Sadikin Bandung in the period January 2016 – December 2020. Methods: This study is a descriptive study using medical record data of patients diagnosed as ameloblastoma. The variables studied included age, gender, time of exposure, plate length, number of screws. Results: From the results of data collection for the last 3 years (2019-2021) at the Oral and Maxillofacial Surgery Section of Hasan Sadikin Hospital Bandung, it was found that the number of patients who underwent mandibular resection procedures in ameloblastoma cases was 25 patients. The patients consisted of 10 males and 15 females. AO plates were used as reconstruction material in 25 cases. Of the 25 cases, the exposure plate was found in 6 cases. Plate exposure occurs 4 years after resection in some cases. Of the 6 patients, 6 patients had plate removal. Conclusion: Complications of plate exposure occur due to several factors such as age, plate length, and lack of adaptation of the plate. We must make a good plan of care during the preoperative period, by optimizing the condition of the patient before surgery to make a plan for proper plate placement, shaping and adjusting the shape of the plate, and estimating the need for graft placement.


Introduction
Mandibular resection is a procedure to treat mandibular diseases or disorders. 1 Mandibulectomy is indicated for diseases involving the mandible. This procedure can be carried out in various settings, including causes of infection (e.g., osteomyelitis), osteoradionecrosis, benign (e.g., ameloblastoma), or malignant neoplastic process (e.g., invasive squamous cell carcinoma) that involves the jaws. 2 Mandibular discontinuity due to mandibular resection led to a loss of facial balance and symmetry. The mandible has a primary role in function and aesthetics. A loss of mandibular continuity disrupts the jaws' integrity and highly affects patients' self-perception and self-confidence.
Mandibular reconstruction aims to close primary wounds, repair phonation and deglutition, and aesthetic recovery in the lower part of the face. Complications related to plate after surgery and screw plate including infection, wound dehiscence, plate exposure, loosening, damage to the screw, and plate fracture can occur. Plate exposure is a common post-surgical complication in mandibular resection followed by reconstruction with plate fixation.

Methods
This study is an analytical observation with a retrospective approach, using the data of plate exposure after mandibular resection in patients diagnosed with ameloblastoma in Hasan Sadikin General Hospital Bandung.
The target population is the population that becomes the final target for the implementation of study results. The target population in this study was all plate exposure after mandibular resection cases in patients diagnosed with ameloblastoma in Dr. Hasan Sadikin General Hospital Bandung. The accessible population is a part of the target population that can be reached by the researchers. The accessible population in this study was ameloblastoma patients with plate exposure after mandibular resection between January 2019 -December 2021 in the Department of Oral and Maxillofacial Surgery of Dr. Hasan Sadikin General Hospital.
The study used data from medical records of ameloblastoma patients with plate exposure after mandibular resection in the Oral and Maxillofacial Surgery Department of Hasan Sadikin General Hospital. The study was conducted after obtaining ethical clearance from the Research Ethics Committee of UNPAD Faculty of Medicine/Hasan Sadikin General Hospital.

Results
The results of data collection from the Department of Oral and Maxillofacial Surgery of RSHS from January 2019-December 2021 obtained 25 ameloblastoma patients who underwent mandibular resection. The data described that the 25 patients were divided into 10 men (40%) and 15 women (60%).

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The figure showed that the majority of ameloblastoma patients were aged < 45 years and > 55 years, which consisted of 3 patients (50%), while there was 1 patient (2.7%) aged 0-10 years old. The incidence of ameloblastoma in Indonesia occurs between 37-50 years old.  According to the data, plate length and screws used varied. The longest plate was 17 holes, while the shortest was 12 holes, depending on the mass. The length of the screws used was 10mm.
The timing of plate exposure after mandibular resection in ameloblastoma patients varied. The graph showed that the timing of plate exposure frequently occurred four years after mandibular resection.

Discussion
The success rate of mandibular reconstruction has increased as a result of the advancement in plate design and material. However, complications of plate exposure after mandibular reconstruction with plate fixation still occur often. There are several factors related to plate exposure. In this study, we examined the variables of plate length, screw size, and number as factors related to plate exposure. Although no significance was found in plate exposure, the significance of these risk factors can not be neglected, considering the biological factor where these factors can affect wound healing. Excision extension is another potential factor that might be related to plate exposure. Nevertheless, we have not discussed excision extension in detail in this study. Previous studies also found a significant correlation between the existence of grafts with plate exposure. Several studies also stated that excision area, malignancy diagnosis, and the thickness of soft tissues covering the plate had a significant correlation with plate exposure.
Many factors might contribute to the exposure of the plate used for primary mandibular reconstruction after mandibular resection. Persistent dead space leads to pressure on the skin covering the plate surface during healing and creates a scar in the wound site. Thin soft tissues overlying the plate surface can cause physical irritation and skin compression to the plate which may contribute to plate exposure. The imbalance of soft tissue overlying the plate surface and the shape of the plate can cause the bulging part from the plate to press the overlying soft tissue and contribute to plate exposure. The area of mandibular resection that covers the midsegment of the mandible can lead to plate exposure. Meanwhile, plate exposure rarely occurs when the resection is limited to the lateral segment.

Conclusion
Based on the data from the last three years (2019-2021) in the Department of Oral and Maxillofacial Surgery of Hasan Sadikin Hospital Bandung, 25 ameloblastoma patients underwent mandibular resection and 6 of them experienced plate exposure. The complication of plate exposure occurs because of several factors, such as age, plate length, and lack of plate adaptation. We must make appropriate treatment planning during the preoperative period by optimizing the patient's condition before the surgery to plan the proper plate placement, form and adjust plate shape, and consider the need for graft.