Mohammed Ghazı Allan SALAHALDIN, BERKEM ATALAY

Evaluation of the relationship between an impacted mandibular third molar and the inferior alveolar canal using cone-beam computed tomography

Aim:Protection and preservation of the inferior alveolar nerve are very important during oral surgery; therefore, the anatomical course should be identified precisely before surgical interventions. Cone-beam computed tomography (CBCT) can provide accurate, high-resolution images in limited regions thus can be used to locate the pathway of the inferior alveolar canal (IAC) and its relation to the other anatomical structures. Materials and Methods:This retrospective study included 100 patients who referred to İstanbul University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery between November 2015-March 2016. Panoramic radiograph and CBCT were taken for each participant to evaluate impacted mandibular third molar (IMTM). The cases were classified, according to the anatomical relationship between the mandibular third molars and the IAC on panoramic radiograph and CBCT. Data were compared using the Tukey test. Results:When the IMTM and IAC were examined, it was determined that ın 62 cases IAC was closer than 1 mm and in 28 cases the distance was between 1-2 mm. IAC and teeth did not associate in 10 cases where the distance was more than 2 mm. Our findings showed that the IAC descended from the retromolar region to the molar region and ascended to the premolar region. The buccal bone is thicker in the molar region, whereas the lingual bone is thicker in the premolar region. Conclusion: CBCT is useful before oral and maxillofacial surgery procedures to avoid inferior alveolar nerve injury.

Mandibular gömülü üçüncü molar dişler ile mandibular kanal arasındaki ilişkinin dental volümetrik tomografi ile değerlendirilmesi

Amaç: Oral cerrahide inferior alveolar sinirin korunması çok önemlidir; Bu nedenle, anatomik pozisyonu, cerrahi müdahalelerden önce kesin olarak tanımlanmalıdır. Konik ışınlı bilgisayarlı tomografi (KIBT), sınırlı bölgelerde doğru yüksek çözünürlüklü görüntüler sağlayabilir, böylece inferior alveolar kanalın (İAK) yolunu ve diğer anatomik yapılarla ilişkisini bulmak için kullanılabilir. Gereç ve Yöntem: Bu retrospektif çalışmaya İstanbul Üniversitesi Diş Hekimliği Fakültesi Oral ve Maksillofasiyal Cerrahi Anabilim Dalı'na Kasım 2015-Mart 2016 tarihleri arasında başvuran 100 hasta dahil edildi. Her bir katılımcıdan mandibular üçüncü molar dişlerin değerlendirilmesi için panoramik radyografi ve KIBT alındı. Olgular mandibuler üçüncü molar dişleri ile panoramik radyografi ve KIBT'deki İAK arasındaki anatomik ilişkiye göre sınıflandırıldı. Veriler, Tukey testi kullanılarak karşılaştırıldı. Bulgular: Mandibular üçüncü molar diş ve İAK incelendiğinde, İAK'nın 62 olguda 1 mm'den daha yakın olduğu ve 28 olguda mesafenin 1-2 mm arasında olduğu saptanmıştır. Mesafenin 2 mm'den fazla olduğu 10 olguda İAK ve dişler birbirine karışmamıştır. Bulgularımız İAK'nın retromolar bölgeden molar bölgeye indiğini ve premolar bölgeye çıktığını gösterdi. Bukkal kemik molar bölgede daha kalın iken, lingual kemik, premolar bölgede daha kalındır. Sonuç: KIBT, inferior alveolar sinir hasarını önlemek için oral ve maksillofasiyal cerrahi işlemlerden önce yararlıdır.

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