Association Between Maxillary Incisor Inclination and Sagittal Condylar Guidance Across Different Skeletal Malocclusions: A Cross-Sectional Study

Objective: This cross-sectional study analyzed the relationship between maxillary incisor inclination and sagittal condylar guidance in patients with and without temporomandibular disorders (TMD) across different skeletal malocclusions, aiming to enhance orthodontic diagnosis and treatment. Materials and Methods: A total of 154 patients from a private clinic with various skeletal malocclusions were consecutively enrolled in this study. Mandibular kinematics were recorded using Modjaw® and TMD signs and symptoms were evaluated using the DC-TMD questionnaire. Pearson’s correlation was applied to assess relationships between incisor inclination (U1–NA, U1–APog, U1–PP) and condylar guidance (right and left). Results: TMD signs or symptoms were present in 31.8% of patients. A weak negative correlation was observed between incisor inclination and sagittal condylar guidance for patients with positive overjet and overbite values. Retroclined maxillary incisors were weakly associated with a steeper condylar path (correlation values between R = −0.122 and R = 0.177). No significant relation was found between maxillary incisors’ inclination and the presence of TMD (p > 0.05). No significant association was found between TMD prevalence and skeletal or dental classifications (p > 0.05). Conclusions: Although some correlations reached statistical significance, their magnitude was below the accepted threshold for small effects (r ≥ 0.30), indicating negligible clinical impact. These findings suggest that maxillary incisor inclination does not meaningfully influence condylar guidance and should not be considered a primary determinant in treatment planning. Instead, it should be integrated only as a contextual variable within a multifactorial functional assessment.