Mandibular İnsizörlerde Görülen Isthmus Tipleri Ve Prevalansı

Yıl 2025, Cilt: 14 Sayı: 3, 161 - 167, 29.09.2025

Eda Gürsu Şahin , Songül Şahin

https://doi.org/10.54617/adoklinikbilimler.1554114

Öz

Amaç
Bu çalışmanın amacı, mandibular keser dişlerin sahip olduğu isthmus tiplerinin ve sıklığının büyütme sistemi ve histokimyasal yöntemler yardımıyla değerlendirilmesidir.
Gereç ve Yöntem
150 adet rastgele seçilmiş insan mandibular keser dişi kullanılmıştır. Kök ucu gelişimi tamamlanmış, kırık, çürük, çatlak olmayan, kanal tedavisi girişiminde bulunulmamış, kanal içerisinde herhangi bir patoloji varlığı tespit edilmemiş dişler çalışmaya dahil edilmiştir. Kuronları uzaklaştırılmış olan kökler, kullanım zamanına kadar %10 formalin içerisinde bekletilmiştir. Fiksasyon ve dekalsifikasyon işlemlerinin ardından, sıralı kesitleri doku takip kasetleri içerisine alınan örnekler Hematoksilen-Eozin ile boyanmış; ardından ışık mikroskobunda x40 büyütme altında incelenmiştir.
Bulgular
İncelenen 150 adet mandibular insizör dişin 105’inde çeşitli isthmus tiplerine rastlandı. En fazla görülen isthmus tipi %44,8 oranında Tip 1; en az %8,6 oranında Tip 3 isthmus görüldü. Örneklerin %30’unda herhangi bir isthmusa rastlanmadı. İsthmusların en fazla görüldüğü apikal 5mm ve 6 mm sectionları istatiksel olarak anlamlı bulundu; görülen isthmus tipleri bakımından ise bir anlamlılık tespit edilmedi.
Sonuç
Mandibular keser dişler istatistiksel olarak anlamlı düzeyde isthmus varyasyonuna sahip, kompleks yapı göstermektedir. Isthmusun kök kanalında hangi lokasyonda olabileceği ve hangi varyasyona sahip olacağı ile ilgili bilgi sahibi olunması; yapılacak tedavi sırasında kullanılacak olan teknik ve enstrüman seçimini etkileyeceği gibi tedavinin başarısı üzerinde de direkt rol oynayacaktır. İsthmus varyasyonu gibi kompleksite gösteren durumlarda, standart enstrümantasyon teknikleri tek başına kök kanal sisteminin temizlenmesinde yeterli olmayacaktır.

Anahtar Kelimeler

Mandibular keser , Histolojik kesit , Isthmus

Types Of Isthmus And Their Prevalence In Mandibular Incisors

Öz

Purpose: This study aimed to evaluate the types of isthmus and their prevalence in mandibular incisors using magnification systems and histochemical methods.
Materials and Methods: This study included 150 randomly selected human mandibular incisors devoid of caries and free of any pathology in the crown or root portion. Samples were preserved in 10% formalin until needed. After fixation and decalcification, serial sections were placed into tissue-tracking cassettes, stained with hematoxylin and eosin, and examined under a light microscope at 40× magnification.
Results: Of the 150 mandibular incisors examined, various types of isthmus were observed in 105. The most frequently observed isthmus type was Type 1, accounting for 44.8% of cases, while the least observed was Type 3, accounting for 8.6%. No isthmus was observed in 30% of the samples. Isthmuses were significantly more common at the apical 5 and 6 mm levels; however, no significant difference was observed in the types of isthmus.
Conclusion: Mandibular incisors exhibit significant variations in isthmuses, indicating a complex structure. Knowledge of the possible location and variations of isthmuses is crucial as it not only influences the selection of techniques and instruments but also directly impacts treatment success. Standard instrumentation techniques alone may not suffice for thoroughly cleaning the root canal system in complex cases, such as those with isthmus variation.

Anahtar Kelimeler

Histological section , Isthmus , Mandibular incisor

Kaynakça

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