Evaluation of the Effect of Orthognathic Surgery on Cervical Lordosis and Head Posture in Class III Patients

Abstract

Objective: This study aimed to evaluate the effects of orthognathic surgery on cervical lordosis and head posture in patients with Class III skeletal deformity. Materials and Methods: A retrospective analysis was conducted on 19 Class III patients who underwent bimaxillary orthognathic surgery and 18 control subjects with skeletal Class I relationship. Preoperative and minimum two-month postoperative lateral cephalograms were assessed. Cervical spine curvature was measured using the Cobb method for CV1–CV2, CV3–CV7, and CV1–CV7 angulations. Statistical comparisons were made using the Mann-Whitney U test, and measurement reliability was confirmed via intraclass correlation coefficients. Results: Significant improvements were observed in cephalometric indicators of skeletal Class III correction, including increased SNA and ANB angles, and improved Wits appraisal. While the CV1–CV7 angle increased by an average of 9.6 degrees, the change was not statistically significant (p = 0.702). No significant postoperative differences were found in cervical or head posture parameters, nor between the study and control groups (p > 0.05). Conclusion: Although orthognathic surgery effectively corrected skeletal discrepancies in Class III patients, it did not result in significant short-term changes in cervical lordosis or head posture. The limited extent of mandibular setback in this cohort may have reduced its biomechanical impact on cervical spine alignment.

Keywords

• Class 3 patients
• Cervical lordosis
• Head posture

Sınıf III hastalarda ortognatik cerrahinin servikal lordoz ve baş postürü üzerine etkisinin değerlendirilmesi

Öz

Amaç: Bu çalışmanın amacı Sınıf III iskeletsel deformitesi olan hastalarda ortognatik cerrahinin servikal lordoz ve baş postürü üzerine etkilerini değerlendirmektir. Gereç ve Yöntemler: Bimaksiller ortognatik cerrahi uygulanan 19 Sınıf III hasta ve iskeletsel Sınıf I ilişkiye sahip 18 kontrol olgusu üzerinde retrospektif bir analiz yapıldı. Ameliyat öncesi ve ameliyat sonrası en az iki aylık lateral sefalogramlar değerlendirildi. Servikal omurga eğriliği CV1-CV2, CV3-CV7 ve CV1-CV7 açılanmaları için Cobb yöntemi kullanılarak ölçüldü. İstatistiksel karşılaştırmalar Mann-Whitney U testi kullanılarak yapıldı ve ölçüm güvenilirliği sınıf içi korelasyon katsayıları ile doğrulandı. Sonuçlar: İskeletsel Sınıf III düzeltmenin sefalometrik göstergelerinde, SNA ve ANB açılarında artış ve Wits değerlendirmesinde iyileşme dahil olmak üzere önemli gelişmeler gözlenmiştir. CV1-CV7 açısı ortalama 9.6 derece artarken, değişiklik istatistiksel olarak anlamlı değildi (p = 0.702). Servikal veya baş duruşu parametrelerinde ya da çalışma ve kontrol grupları arasında ameliyat sonrası anlamlı bir fark bulunmamıştır (p > 0.05). Tartışma: Ortognatik cerrahi, Sınıf III hastalarda iskeletsel uyumsuzlukları etkili bir şekilde düzeltmesine rağmen, servikal lordoz veya baş postüründe kısa vadede önemli değişikliklere yol açmamıştır. Bu kohorttaki mandibular gerilemenin sınırlı olması, servikal omurga hizalanması üzerindeki biyomekanik etkisini azaltmış olabilir.

Anahtar Kelimeler

• Sınıf 3 hasta
• Servikal lordoz
• Baş postürü

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