Purpose: To investigate the functional and structural characteristics of temporomandibular joint(TMJ) in introverted deep overbite patients with severe wear, to analyze the correlation between the vertical distance of the lower 1/3 of the face and TMJ space, and to compare the clinical efficacy of multidisciplinary treatment with orthodontics and prosthodontics on TMJ function.
Methods: Eighty patients with deep overbite and severe abrasion and forty subjects with normal occlusion admitted to our hospital from January 2019 to June 2023 were enrolled in this study. The clinical data were collected and the functional and structural characteristics of TMJ were collected. Eighty patients with deep overbite and severe abrasion were randomly divided into control group and experimental group, with 40 cases in each group. The control group was treated with restoration, and the experimental group was treated with orthodontic combined with restoration. The efficacy and CBCT imaging indexes were evaluated during the treatment. SPSS 26.0 software package was used for statistical analysis.
Results: The mean Helkimo index of patients with deep overbite and severe abrasion was significantly higher than that of patients with normal occlusion(P＜0.05). CBCT scan showed that anterior space of TMJ in patients with deep overbite and severe abrasion significantly increased than those with normal occlusion(P＜0.05), while superior and posterior space were significantly decreased than those with normal occlusion(P＜0.05). Lateral cephalometric analysis showed that the vertical distance of submaxillofacial 1/3 in patients with deep overbite and severe abrasion significantly decreased than normal occlusion(P＜0.05). The Helkimo index of the two groups after treatment was significantly reduced (P＜0.05), and the Helkimo index of the experimental group was significantly lower than that of the control group (P＜0.05). The anterior TMJ spaces of the two groups significantly decreased after treatment, and the superior and posterior TMJ spaces were significantly increased(P＜0.05), but there was no significant difference in TMJ space between the experimental group and the control group(P＞0.05). The vertical distance of submaxillofacial 1/3 in patients in both groups significantly increased after treatment(P＜0.05). There were correlations between the vertical distance of lower one-third of face and the anterior, superior and posterior TMJ spaces(P＜0.05).
Conclusions: The clinical effect of dual disciplinary treatment of orthodontics and prosthodontics on TMJ function was significantly better than that of prosthodontics alone, and the effect on TMJ structure correction is similar to that of prosthodontics.