Three-dimensional changes in hard-tissue symmetry and soft-tissue parameters after stabilization splint therapy in adult patients with temporomandibular joint disorders and mandibular deviation: A retrospective study

Madiha Mohammed Saleh Ahmed; Pengyu Chen; Zhongyi Xiao; Chunshen Li; Cui Zhang; Xin Wang; Moutaz Mohammed Saleh Ahmed; Badr Sultan Saif; Xi Chen; Yunshan Zhao; Abeer A Almashraqi

doi:10.1016/j.adaj.2025.05.012

Three-dimensional changes in hard-tissue symmetry and soft-tissue parameters after stabilization splint therapy in adult patients with temporomandibular joint disorders and mandibular deviation: A retrospective study

J Am Dent Assoc. 2025 Jul 3:S0002-8177(25)00346-0. doi: 10.1016/j.adaj.2025.05.012. Online ahead of print.

Authors

Madiha Mohammed Saleh Ahmed, Pengyu Chen, Zhongyi Xiao, Chunshen Li, Cui Zhang, Xin Wang, Moutaz Mohammed Saleh Ahmed, Badr Sultan Saif, Xi Chen, Yunshan Zhao, Abeer A Almashraqi

PMID: 40608029
DOI: 10.1016/j.adaj.2025.05.012

Abstract

Background: The authors analyzed 3-dimensional changes in hard-tissue symmetry (HTS) and associated soft-tissue contour (STC) and evaluated soft-tissue thickness (STT) after stabilization splint (SS) therapy in adult patients with temporomandibular joint disorder (TMD) and mandibular deviation (MD).

Methods: In this retrospective clinical study, 35 adults with TMD and MD were treated with SS therapy; the patients' mean (SD) age was 25.14 (6.11) years. Pre- and posttherapy cone-beam computed tomography scans were analyzed. HTS, STC, and STT were analyzed in 3 dimensions. A paired t test or Wilcoxon rank sum test was used and P less than .05 was considered significant.

Results: Patients received SS therapy for a mean (SD) of 9.49 (4.02) months. HTS parameters (ie, mandibular midline shift angle and anterior, middle, and posterior symmetry) on the deviated side decreased significantly (P < .001, P < .001, P < .010, and P < .042, respectively). The associated STC (ie, soft-tissue chin canting, soft-tissue anterior symmetry, soft-tissue middle symmetry, and soft-tissue posterior symmetry) on the deviated side decreased significantly (P < .001, P < .001, P < .012, and P < .041, respectively). The hard-tissue chin deviation was improved in 85.71% of the patients and associated soft-tissue chin deviation was improved in 74.29%.

Conclusions: In patients with TMD and MD, SS therapy resulted in considerable correction of HTS in roll rotation, centering the mandible, and soft tissue followed hard-tissue movement, resulting in improved STC and associated soft-tissue chin deviation. However, STT remained unchanged.

Practical implications: SS therapy offers a noninvasive option for improving HTS and STC in adult patients with TMD and MD and contributes to the diagnosis and treatment of clinical conditions. However, its application is influenced by factors such as cost, accessibility, follow-up needs, and patient compliance.

Keywords: Hard-tissue symmetry; mandibular deviation; soft-tissue contour; soft-tissue thickness; stabilization splints; temporomandibular joint disorders.