以鎳鈦旋轉器械配合不同大小根尖修形後根管清潔度之比較

Root Canal Cleanliness Comparison after Different Sizes of Apical Enlargement Following Preparation with Ni-Ti Rotary Instrument

林國豐(Kuo-Feng Lin)

指導教授 ： 洪純正

高雄醫學大學/口腔醫學院/牙醫學研究所/碩士(2007年)

https://doi.org/10.6832/KMU.2007.00083

摘要

根管治療最重要的目的就是要將根管系統中細菌和殘屑的數量降至最低甚至沒有，來預防或治療根尖牙周炎的發生。要達到這個目的，取決於如何作好根管系統的清潔與修形，並將修形過後之根管系統作良好的充填與封閉。因此，如何同時達到良好的清潔與成功的修形，一直是根管治療醫師所努力的方向。本研究之目的在於探討鎳-鈦旋轉器械修形之後，在同樣的修形錐度之下，比較不同大小的根尖修形對於其管壁清潔率的影響。以期找出適當的根尖修形尺寸，達到最佳效率的根管修形與清潔，而避免根尖修形過大或不足。
本實驗包括四個實驗組，每組各有20個根管，利用ProTaperTM鎳-鈦旋轉根管銼（ProTaperTM rotary file）配合冠端向下法（crown - down technique）加以修形。A組之最終修形號數為Finishing File No.3，B組修形至F3/＃30，C組修形至F3/＃35，而D組則修形至F3/＃40。在實驗過程中並配合2.5 %次氯酸鈉溶液及0.5 M EDTA溶液作沖洗。之後將牙根縱劈，並利用掃瞄式電子顯微鏡觀察縱劈後牙根根管壁之冠部、中部及根尖部，在200倍下觀察其殘屑含量，在1000倍下觀察其塗抹層含量，並加以評分。將結果使用統計軟體加以分析。
結果顯示，若以相同尺寸的根尖修形，在根尖部之殘屑及塗抹層殘留都是三個部位中最多者，中部其次，冠部最少。而不同尺寸的根尖修形之間，各組殘屑和塗抹層分數在冠部和中部無顯著差異；但在根尖部的殘屑分數，A組（F3）與C組（F3/＃35）、D組（F3/＃40）之間分別具顯著差異，B組（F3/＃30）與C組、D組之間分別具顯著差異；根尖部的塗抹層分數在A組與C組、D組之間分別具顯著差異。而分析之結果亦顯示根管位置及根尖修形尺寸都是殘屑殘留之顯著影響因素，影響塗抹層殘留的顯著因素則為根管位置。
由以上結果可得到結論：根管修形時，不論根尖修形至何種尺寸大小，根尖部之清潔率皆為整個根管之中最差者。在根尖錐度為.09的條件下，若增加根尖修形的尺寸，可以提高根管清潔率及沖洗效益。以ProTaperTM鎳-鈦旋轉器械修形下顎第一或第二大臼齒的近心根管時，就根尖部殘屑移除之成效而言，至少需修形至＃35 K型根管銼；就根尖部塗抹層移除之成效而言，單純只擴大到F3而未配合手動根尖修形仍是不夠的。

關鍵字

根管清潔率 ； 鎳-鈦旋轉器械 ； 根尖修形 ； 殘屑 ； 塗抹層

並列摘要

The most important objective of root canal therapy is to minimize the number of microorganisms and pathologic debris in root canal system to prevent or treat periradicular periodontitis. It depends on how to clean and shape the root canal system to achieve the objective. The purpose of this study was to compare the cleanliness of the root canal wall in different levels after preparation with the same tapering Ni-Ti rotary instruments and apical preparation with different hand file.
A total of 40 roots with 80 canals were divided into four groups. ProTaperTM Rotary Files were used to prepare the root canals with crown – down technique. The four different canal groups used the same final ProTaperTM Rotary Files, and were prepared apically without and with hand file in different sizes, which were group A（without hand file preparation ）, group B（＃30 K file）, group C（＃35 K file）, group D（＃40 K file） respectively. The 5.25% NaOCl and 0.5 M EDTA were used to enhance the cleanliness. After the roots were split longitudinally, the scanning electron microscope (SEM) study was to compare the cleanliness of the root canal walls at low (× 200) and high (× 1000) magnifications at the coronal, middle and apical levels to calculate the amounts of debris and smear layer. ANOVA and MANOVA were used to analyze the differences in the amounts of debris and smear layer among four groups and three positions.
The highest scores of debris and smear layer were found in the apical level. There was no significant difference in the coronal and middle levels between all groups. In the apical level, group A left significantly more debris and smear layer compared with group C and group D； group B left significantly more debris compared with group C and group D. The two-way ANOVA showed that the canal position and the size of apical preparation were both significant risky factors for debris scores；the canal position was significant risky factors for smear layer scores.
In summary, the apical third cleanliness was worse than the other positions. The cleaning efficiency of debris could be improved by increasing the apical preparation size to ＃35 K file. The cleaning efficiency of smear layer for Ni-Ti rotary instruments without hand file preparation apically was not adequate.

並列關鍵字

canal cleanliness ； Ni-Ti rotary instruments ； apical preparation ； debris ； smear layer

參考文獻

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