Anterior Loop of the Mental foramen in a Turkish Subpopulation with Dentate Patients: a Cone Beam Computed Tomography Study

Year 2015, Volume: 5 Issue: 4, 231 - 238, 29.12.2015

Arzu Demır Elif Izgı Filiz Namdar

https://doi.org/10.5455/musbed.20150715121209

Abstract

Objective: The aim of this retrospective study was to evaluate the frequency and types of the mental foramen’s anterior loop in a Turkish subpopulation on cone-beam computed tomography (CBCT).

Methods: 279 dentate patients (138 females, 141 males, age range 20- 69 years) were evaluated for both side of mandible. Type 1 was described as the mental branch leaved the inferior alveolar nerve posterior to the opening of the mental foramen. Type 2 was described as the mental branch leaved the inferior alveolar nerve perpendicular to the opening of the mental foramen. Type 3 was described as the mental branch leaved the inferior alveolar nerve anterior to the mental foramen. It was assumed that there was no loop in type 1 and 2. Type 3 indicated the presence of anterior loop.

Results: The distribution of type 3, type 2 and type 1 were noted 59.5%, 31.9% and 8.6% respectively. If the type was same on both sides distribution of type 1, type 2 and type 3 were noted 1.8%, 17.2% and 45.5% respectively. There was no statistically significant difference on the left side and right side between males and females.

Conclusions: CBCT can be used safely to observe three-dimensionally the track of mental nerve from the inferior alveolar nerve to the mental foramen. Thus the divergence of mental nerve can be evaluated if there is a loop mesially from the mental foramen for various surgical operations involving interforaminal area.

Keywords

Cone beam computed tomography, mandibular canal, inferior alveolar nerve, mental foramen, anterior loop

Dişli Hasta Grubundan Oluşan Türk Subpopülasyonunda Konik Işınlı Bilgisayarlı Tomografi ile Mental Foramende Anterior Loop Değerlendirmesi

Abstract

Amaç: Bu
retrospektif çalışmanın amacı mental foramende anterior lup varlığının Türk
subpopülasyonundaki sıklığını ve tiplerini konik ışınlı bilgisayarlı tomografi
(KIBT) ile değerlendirmektir.

Yöntemler: Çalışmada
20-69 yaşları arasında 138 kadın, 141 erkek olmak üzere 279 dişli hasta değerlendirilmiştir.
Mandibular kanalın mental foramende sonlanma şekli 3 tip olarak sınıflandırılmıştır.
Buna göre Tip 1; mental dalın inferior alveolar siniri mental foramenin
posteriorunda kalacak şekilde terk etmesi olarak tanımlanmıştır. Tip 2; mental
dalın infe­rior alveolar siniri mental foramene dik olacak şekilde terk etmesi
olarak tanımlanmıştır. Tip 3; mental dalın inferior alveolar siniri mental
forame­nin anteriorunda kalacak şekilde terk etmesi olarak tanımlanmıştır. Tip
1 ve 2 de anterior lup varlığından bahsedilmezken Tip 3’ ün anterior lup varlığını
gösterdiği belirtilmiştir.

Bulgular: Tip
3, Tip2 ve Tip1 sonlanma şekillerinin dağılımı sırasıyla %59.5, %31.9 ve %8.6
olarak belirlenmiştir. Aynı hastada sağ ve sol tarafta aynı anda Tip 1, Tip 2
ya da Tip 3 sonlanma şekli dağılımları ise sırasıyla %1.8, %17.2 ve %45.5 olarak
bulunmuştur. Sağ ve sol tarafta kadınlar ve erkekler arasında istatistiksel
olarak anlamlı bir farklılık tespit edilmemiştir.

Sonuç: KIBT;
mental sinirin inferior alveolar sinirden ayrılıp mental foramene ulaşmak için
izlediği yolu üç-boyutlu olarak değerlendirmek için güvenle kullanılabilir.
Foramenler arası bölgeyi ilgilendiren bir çok cerrahi operasyon öncesinde,
mental foramenin meziyalinde mental sinir dalına ait olası bir lup varlığı
kolaylıkla tanımlanabilir.

Keywords

Konik ışınlı bilgisayarlı tomografi, mandibular kanal, inferior alveoler sinir, mental foramen, anterior lup

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