Three‐dimensional evaluation of the temporomandibular joints after unilateral surgically assisted rapid maxillary expansion in adults: A preliminary retrospective study

BACKGROUND: Unilateral surgically assisted rapid maxillary expansion (U-SARME) is a successful method for correction of true unilateral posterior crossbite (TUPC). OBJECTIVES: This retrospective preliminary study aimed to evaluate the position and morphology of condyles in TUPC cases and the effects of U-SARME on condyle with the help of cone beam computed tomography (CBCT). METHODS: Fifteen patients (mean age: 18.69 ± 1.59 years) who were diagnosed as TUPC and undergone U-SARME were selected. Preoperative (T0) and after 6-month retention (T1) DICOM data of CBCT images were evaluated with MIMICs version 19.0 software. Condylar morphology (medio-lateral and antero-posterior dimensions) and position (anterior, posterior, medial and lateral joint spaces, frontal/axial axis angles, the ratio of posterior to anterior joint space and the percentage of posterior to anterior joint space) were evaluated. Student's t-test was used for intergroup (crossbite, normal) comparisons. Paired-samples t-test was used for intra-group comparisons (p = .05). RESULTS: There were no positional or dimensional asymmetry of the condyles between crossbite and normal sides initially and after expansion. Regarding T0-T1 changes, while significant increase was determined in medial (0.3 ± 0.29 mm; p = .001) and superior (0.39 ± 0.7 mm; p = .045) joint spaces on crossbite side, posterior (0.79 ± 0.99 mm; p = .008), superior (0.5 ± 0.79 mm; p = .029) and lateral joint spaces (0.31 ± 0.54 mm; p = .042) presented significant increases on normal side. However, no significant changes were found between crossbite and normal sides at T0 and T1. CONCLUSIONS: Condyles were symmetrical in true unilateral posterior crossbite cases and the symmetry were not disrupted following U-SARME.