利用錐狀束電腦斷層判讀台灣族群頦孔解剖形態之研究

The study of the characteristics of mental foramen by using cone-beam computed tomography in Taiwanese population

陳彥儒(Yen-Ju Chen)

指導教授 ： 張育超

中山醫學大學/口腔醫學院/牙醫學系/碩士(2022年)

https://doi.org/10.6834/csmu202200223

摘要

頦孔 (mental foramen) 是下顎骨重要的解剖構造，內有神經及血管通過，下嘴唇麻痺及感覺神經異常，是手術後潛在的風險，利用錐狀束電腦斷層 (cone beam computed tomography，簡稱CBCT) 作為術前的評估工具，可以提供更精細的影像資訊，有助於訂定更精準的治療計畫，避免手術所產生的併發症。本研究收集某醫療院所從2010年1月至2022年4月的錐狀束電腦斷層影像資料庫，分析台灣人族群頦孔的位置、大小、形狀、開口角度及與下顎骨底和下齒槽神經的位置分佈情形，量測各項數據給臨床醫師作為手術前評估之參考。從資料庫中篩選出166位病患的影像資料，其中男性有91位，女性有75位，平均年齡為44.7 ± 16.8歲，合計共有300個頦孔，包含右側154個，左側146個。測量結果顯示，頦孔最常見的位置在第二小臼齒下方 (46%)，其次為第一小臼齒與第二小臼齒之間 (38.7%)；頦孔的最低點到下顎骨底的距離在男性的測量結果較大 (p<0.0001)；女性的頦孔的平均向上開口角度為41.02 ± 11.07度，男性為42.86 ± 10.54度；頦孔的形狀為圓形約佔75.7%、垂直橢圓形 (13.6%) 及水平橢圓形 (10.7%)。經過邏輯回歸分析後發現，年紀越大的族群，頦孔位置有越往後牙出現的現象，且當頦孔位置位於第二小臼齒下方或更後方時，下齒槽神經則位於較靠近舌側的位置。綜合本研究結果顯示，頦孔的位置及形態存在著很高的變異性，建議手術前可運用錐狀束電腦斷層做更完整的數位影像檢查，期能提高患者手術過程的安全性和醫療品質的滿意度。

關鍵字

下齒槽神經 ； 頦神經 ； 頦孔 ； 錐狀束電腦斷層 ； 神經損傷 ； 病人安全

並列摘要

Mental foramen is an important bilateral anatomical structure in mandible. It transmits the mental nerve and blood vessels that supply the lower jaw. Paresthesia and lip numbness are the common complications related to nerve injury during dental treatment. The aim of this study was to evaluate the characteristics of mental foramen by using cone-beam computed tomography (CBCT) in Taiwanese population to avoid surgical complications. Total 166 CBCT images were analyzed from a dental clinic from January 2010 to April 2022. The position of mental foramen was described related to the location of mandibular tooth. The distance between mental foramen to the inferior border of the mandible was measured. The shape of mental foramen was classified according to the ratio of horizontal width and vertical height. The position of the inferior alveolar nerve in the cross-sectional view was also detected. In this study, the most prevalent position of mental foramen was found below the second premolar (46%) followed by the position between the first and second premolars (38.7%). Males had the greater distance from the mental foramen to the inferior border of the mandible than those of females (p<0.0001). The average opening angle in females and males are 41.02° ± 11.07° and 42.86° ± 10.54°, respectively. The predominant shape of mental foramen was the round type (75.7%). The logistic regression analysis showed when the mental foramen was below second premolar or more posteriorly, the inferior alveolar nerve position was prone to the lingual surface of the mandible (adjusted odd ratio: 2.70, 95% CI 1.38-5.28). In conclusion, it is important to identify the variations of mental foramen before dental treatment to avoid infra alveolar nerve injury. CBCT acts as a good diagnosis tool to prompt patient safety.

並列關鍵字

inferior alveolar nerve ； mental nerve ； mental foramen ； cone-beam computed tomography ； nerve injury ； patient safety

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