論下顎鈦金屬重建骨板之併發症與其臨床危險因子之相關性研究

Abstract

腫瘤切除後重建下顎功能和連續性一直是頭頸部重建手術領域中一大挑戰。 一般臨床上相信, 腫瘤切除後以骨移植重建可獲得最佳的治療品質。 然而並非每位患者都能接受此種長時間的手術, 此時以重建骨板暫時性或永久的予以適當復形便是另一可行的選擇方案。 現在臨床上仍以鈦金屬重建骨板以其好的生物相容性和操作便利性成為最受歡迎的重建材料之ㄧ。 然而已有多篇國外研究探討其造成術後的併發症- 諸如: 骨板露出, 骨板斷裂, 傷口感染, 和骨釘鬆脫…等, 此類併發症往往會造成鈦金屬重建骨板在臨床應用上的限制, 因而本篇研究希望建立台大醫院本身鈦金屬重建骨板之併發症與其臨床相關因子的相關性研究, 可與國外之研究相比較, 並期望提供臨床上使用的一些建議。 本研究蒐集了1995年到2007年, 共146例在臺大醫院口腔顎面外科接受腫瘤切除手術, 和術後鈦金屬骨板重建手術。 病患資料的蒐集分成了三個部份: 術前(年齡, 性別, 診斷, BMI值), 術中(手術日期, 手術切除範圍, 骨板廠牌, 軟組織皮瓣, 骨皮瓣, 骨釘數目, 骨板樣式), 和術後(術後電療, 術後仍有咬合功能之牙齒數目, 併發症, 追蹤時間)。 我們使用卡方檢定, 單變數回歸, 和多變數回歸模形分析資料, 並使用Kaplan-Meier 存活率分析圖表描述併發症與危險因子的相關性。 本研究的結果顯示年齡和診斷是兩個非常顯著的獨立因子, 其中年齡小於50歲的病患有較佳的組織回復力, 術後併發症發生率明顯低於年齡較大的組別。 而術前診斷為惡性腫瘤和放射線性骨壞死的組別其併發症發生率也顯著較良性腫瘤組為大。 另外, 本研究之結果也同意術後有實施軟組織皮瓣修補手術可提供足夠的軟組織覆蓋和較佳的骨板耐受性。 而第二階段的骨重建手術越快進行越好, 尤其是對那些術後仍保留咬合功能的患者。 本研究的結果也同意術前或術後電療會導致組織纖維化和進ㄧ步骨板露出風險的增加。 另外, 本研究也建議使用鈦合金會比純鈦材料可提供更強的抗性可抵抗術中彎折骨板導致的壓力集中作用, 進ㄧ步會造成金屬疲勞和骨板斷裂。 此外, 考慮增加骨釘內徑或改變骨釘的排列(諸如: 四方形或三角形)皆有機會改善應力的分佈而能減少骨板斷裂或骨釘鬆脫的可能性。 總之, 若我們能在術中和術後適當的減少骨板使用的併發症, 便能大大改善臨床上骨板使用的適應性和病患的容忍度, 使鈦金屬重建骨板成為一臨床上有效的替代選擇。

The appropriate reconstruction for the mandibular defect after oncological resection is one of the most challenging area of head and neck surgery. The titanium reconstruction plate is one of the most popular material used in oral and maxillofacial reconstruction. However, many complications such as plate exposure, plate fracture, infection, or bony nonunion could restrict the application of reconstruction plate and more expensive treatment cost. So that the research for the relationship between the complications of titanium reconstruction plate and their clinical risk factors could provide some suggestions for improvement of clinical use of reconstruction plate. There are already some studies published for discussing this issue, but there is still not a study to compare the data of the patients in north Taiwan with other places. So we collect all patients with titanium reconstruction plate reconstruction after oncological resection in the Department of Oral and Maxillofacial Surgery, National Taiwan University, from 1995 to 2007. Total 146 cases were included in our study. The clinical risk factors were collected in three separated groups- Preoperative (Age, gender, diagnosis, preoperative radiotherapy, and BMI), intraoperative (The date of surgery, size of defect, brand of plate, screw numbers, bone graft, soft tissue graft, type of plate), and postoperative (Postoperative radiotherapy, postoperative remained occlusion, complications, follow up duration). Then all data were analyzed with chi-square test, univariate analysis, and Cox proportional hazard regression model. We also introduced Kaplan-Meier survival rate graphs to describe the relationship between complications and risk factors. The results showed that- First, the age and the diagnosis were two strongly independent factors. The younger patients have better tissue recovery capacity, so that the complication rate would be less than the more elderly group. Then the osteoradionecrosis and malignant group showed higher complication rate than the benign group. Second, our results also agreed with that the post-oncological soft tissue graft could provide sufficient volume of tissue coverage and better plate tolerance. Third, the secondary bone reconstruction should be performed as early as possible especially for the patients with postoperative remained occlusion. Fourth, the Leibinger reconstruction plate would provide better tensile strength tolerance to resist the bending induced metal fatigue and further plate fracture than the Mondeal group. Fifth, both the pre- and post-operative radiotherapy induced higher complication rate. Sixth, our study also suggested that enlargement of the internal thread of screws or change the configuration of the screwholes to rectangular or square could improve the torsion moment distribution. In conclusion, if we could prevent the avoidable risk factors intra- and post-operatively, the titanium reconstruction plate could also provide acceptable functional and aesthetic restoration for temporal or permanent reconstruction for the patients whose conditions could not tolerate long time reconstruction surgery. The titanium reconstruction plate could also be an effective alternative reconstruction material.