Longitudinal CBCT evaluation of cervical vertebral adaptation following stabilization splint therapy and subsequent orthodontic treatment in temporomandibular disorders

Abstract This retrospective longitudinal cone-beam computed tomography (CBCT) study evaluated cervical vertebral adaptation following stabilization splint (SS) therapy and subsequent orthodontic treatment in 50 adults with skeletal Class II malocclusion and temporomandibular disorders (TMD). Of these, 25 received SS therapy followed by orthodontic treatment, whereas 25 underwent conservative non-splint management followed by orthodontic treatment. In the SS group, the OPT/CVT angle decreased by 3.24° after SS therapy ( P  < 0.001), with significant changes also observed in SNL–OPT, SNL–CVT, the C2–C5 Cobb angle, and C1–C2 distance. These changes were largely maintained after orthodontic treatment. The comparison group showed no significant longitudinal changes in the 15 cervical measurements. Baseline-adjusted treatment-pathway analysis showed lower final OPT/CVT and C2–C5 Cobb angle values in the SS-plus-orthodontic group. These findings indicate that measurable craniocervical adaptations occurred predominantly during SS therapy and were largely maintained during subsequent orthodontic treatment. Prospective multicenter studies are needed to establish causality and long-term clinical significance.