EVALUATION OF THE RELATIONSHIP BETWEEN IMPACTED MANDIBULAR THIRD MOLARS AND THE INFERIOR ALVEOLAR CANAL USING CONE-BEAM COMPUTED TOMOGRAPHY

Abstract

Objective: The aim of this study was to evaluate the relationship between impacted mandibular third molars and the mandibular canal using cone-beam computed tomography (CBCT), and to investigate the association of mandibular canal position, tooth angulation, age, and sex with inferior alveolar nerve contact. Materials and Methods: In this retrospective study, CBCT images obtained between May 2021 and June 2025 at the Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Dicle University, were evaluated. A total of 366 impacted mandibular third molars from 250 patients were included in the study. The position of the mandibular canal relative to the tooth roots was classified as buccal, lingual, apical, or interradicular. Tooth angulation was assessed according to the Winter classification. The relationships between mandibular canal position, inferior alveolar nerve contact, and age, sex, and tooth angulation were statistically analyzed. Results: A total of 366 impacted mandibular third molars from 250 patients were evaluated. The mean age of the patients was 29.31 ± 8.44 years, and the proportions of female and male participants were equal (50.0% each). The most common impaction type was mesioangular (45.4%), while the most frequent mandibular canal position was apical (44.3%). The rate of direct contact between the inferior alveolar canal and the tooth roots was 64.5%. No statistically significant association was found between age or sex and mandibular canal position or nerve contact (p>0.05). In contrast, statistically significant associations were observed between the Winter classification and mandibular canal position (p=0.032), as well as nerve contact (p=0.001). The rate of nerve contact was higher in mesioangular impactions compared with the other angulation types. Conclusion: CBCT provides reliable and detailed information for evaluating the relationship between impacted mandibular third molars and the inferior alveolar canal. Mandibular canal position and tooth angulation were found to be associated with inferior alveolar nerve contact, whereas age and sex were not significant determining factors. These findings suggest that surgical planning should be performed more carefully, particularly in mesioangular impactions and in cases with lingual or interradicular canal positions.

Keywords

• Impacted mandibular third molar
• inferior alveolar kanal
• cone-beam computed tomography
• Inferior alveolar nerve

Gömülü Mandibular Üçüncü Molar Dişler ile İnferior Alveolar Kanal Arasındaki İlişkinin Konik Işınlı Bilgisayarlı Tomografi Kullanılarak Değerlendirilmesi

Abstract

Amaç: Bu çalışmanın amacı, gömülü mandibular üçüncü molar dişler ile mandibular kanal arasındaki ilişkinin konik ışınlı bilgisayarlı tomografi (CBCT) kullanılarak değerlendirilmesi ve mandibular kanal pozisyonu, diş angulasyonu, yaş ve cinsiyet gibi faktörlerin inferior alveolar sinir teması ile ilişkisinin araştırılmasıdır. Gereç ve Yöntem: Bu retrospektif çalışmada, Dicle Üniversitesi Diş Hekimliği Fakültesi Ağız, Diş ve Çene Cerrahisi Anabilim Dalı’nda Mayıs 2021–Haziran 2025 tarihleri arasında elde edilen CBCT görüntüleri değerlendirildi. Çalışmaya 250 hastaya ait toplam 366 gömülü mandibular üçüncü molar diş dahil edildi. Mandibular kanalın diş köklerine göre konumu bukkal, lingual, apikal ve interradiküler olarak sınıflandırıldı. Dişlerin angulasyonu Winter sınıflamasına göre değerlendirildi. Mandibular kanal pozisyonu, inferior alveolar sinir teması ve bunların yaş, cinsiyet ile diş angulasyonu arasındaki ilişkileri istatistiksel olarak analiz edildi. Sonuç: CBCT, gömülü mandibular üçüncü molar dişler ile inferior alveolar kanal arasındaki ilişkinin değerlendirilmesinde güvenilir ve ayrıntılı bilgiler sunmaktadır. Mandibular kanal pozisyonu ve diş angulasyonunun inferior alveolar sinir teması ile ilişkili olduğu, buna karşın yaş ve cinsiyetin belirleyici faktörler olmadığı görülmüştür. Bu bulgular, özellikle mezioangüler gömüklüklerde ve lingual/interradiküler kanal yerleşimlerinde cerrahi planlamanın daha dikkatli yapılması gerektiğini göstermektedir.

Keywords

• Gömülü mandibular üçüncü molar
• inferior alveolar kanal
• konik ışınlı bilgisayarlı tomografi
• inferior alveolar sinir

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