Konik ışınlı bilgisayarlı tomografi görüntülerinde mandibular morfometrik ölçümler ile cinsiyet tahmininin değerlendirilmesi

Abstract

Amaç: Tanımlanamayan insan kalıntılarının cinsiyet tayini, adli soruşturmaların temel unsurlarından biridir. Yüz kemikleri arasında mandibula, en sağlam ve dayanıklı yapı olması nedeniyle kişisel tanımlama açısından önemli bir anatomik yapıdır. Bu çalışmanın amacı, konik ışınlı bilgisayarlı tomografi (CBCT) ile elde edilen mandibular metrik parametrelerin cinsiyet belirlemedeki potansiyelini değerlendirmektir. Yöntem: Yaşları 18 ile 81 arasında değişen toplam 199 bireyin (72 erkek, 127 kadın) CBCT görüntüleri retrospektif olarak analiz edilmiştir. Ölçülen dokuz mandibular parametre; mandibular açı, koronoid uzunluğu, kondiler uzunluk, minimal ramus genişliği, mandibular uzunluk, bigonial genişlik, bikondiler genişlik, bimental genişlik ve simfisyal yüksekliği içermektedir. İstatistiksel analizlerde tekrarlı ölçümler için ANOVA, bağımsız örneklemler t-testi, Pearson korelasyon analizi ve diskriminant fonksiyon analizi uygulanmıştır. Bulgular: Ölçülen dokuz parametreden sekizi —kondiler uzunluk, koronoid uzunluk, mandibular uzunluk, bigonial genişlik, bikondiler genişlik, bimental genişlik, simfisyal yükseklik ve minimal ramus genişliği— cinsiyetler arasında istatistiksel olarak anlamlı fark göstermiştir (p < 0.05). Tüm bu ölçümlerde erkek bireyler daha yüksek ortalama değerlere sahipken, mandibular açı kadınlarda bir miktar daha yüksek olmakla birlikte bu fark istatistiksel olarak anlamlı bulunmamıştır (p > 0.05). Diskriminant fonksiyon analizi sonucunda genel cinsiyet sınıflandırma doğruluğu %91.5 olarak elde edilmiştir. Sonuç: Bu bulgular, adli bağlamda mandibulanın cinsiyet tayini açısından güvenilir bir yapı olduğunu göstermektedir. CBCT görüntülerinden elde edilen mandibular ölçümler, cinsiyet dimorfizminin doğru ve tekrarlanabilir göstergeleri olarak değerlendirilebilir. Bulguların daha geniş ve farklı popülasyonlarda doğrulanabilmesi için ileri düzey çalışmalara ihtiyaç duyulmaktadır.

Keywords

• Adli Bilimler
• Konik Işınlı Bilgisayarlı Tomografi
• İskelet Temelli Cinsiyet Belirleme
• Antropometri

Evaluation of sex estimation through mandibular morphometric measurements on cone-beam computed tomography images

Abstract

Aims: Sex estimation of unidentified human remains is a critical component of forensic investigations. Among facial bones, the mandible is the most robust and resilient structure, making it a valuable element for personal identification. The aim of this study was to evaluate the potential of mandibular metric parameters-obtained via cone-beam computed tomography (CBCT)-for determining sex. Methods: CBCT scans of 199 individuals (72 males and 127 females), aged between 18 and 81 years, were retrospectively analyzed. Nine mandibular parameters were measured including the mandibular angle, coronoid and condylar lengths, minimal ramus breadth, and mandibular length, along with bigonial breadth, bicondylar breadth, bimental breadth, and symphyseal height. Statistical analyses included repeated measures ANOVA, independent samples t-test, Pearson correlation, and discriminant function analysis. Results: Males consistently exhibited higher mean values across all parameters, except for the mandibular angle, which was slightly greater in females (female: 119.33±0.56; male: 118.79±0.75) but not statistically significant (p=0.566). The most influential variables, based on structure matrix coefficients, were left coronoid length (0.791), right coronoid length (0.649), left condylar length (0.492), and bigonial breadth (0.477). Discriminant function analysis yielded a high overall sex classification accuracy of 91.5%. Conclusion: The mandible demonstrated high discriminative power, with CBCT-derived measurements providing accurate and reproducible indicators of sexual dimorphism. These findings underscore the utility of mandibular morphometry as a reliable tool for sex estimation in forensic practice.

Keywords

• Forensic sciences
• cone beam computed tomography
• sex determination by skeleton
• anthropometry

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