[Bone remodeling in patients with juvenile condylar resorption after stabilization splint treatment]

Objective: To investigate bone remodeling in patients with different types of juvenile condylar resorption after stabilization splint treatment using cone-beam CT (CBCT). Methods: Fifty-nine juvenile condylar resorption patients (114 sides of condyle) treated with stabilization splint from January 2012 to May 2018 in Department of Temporomandibular Joint, Stomatological Hospital of Chongqing Medical University were selected as splint group, while twenty-four patients (48 sides of condyle) who underwent natural remodeling without stabilization splint treatment after 6-12 months were severed as control group. Pre-and post-treatment CBCT was taken for all patients. There were three types of condyles (including type Ⅰ, type Ⅱ and type Ⅲ) before treatment and four types of condyles (including progression, no changes, stable without new bone and remodeled with new bone) after treatment. Progression and no change were considered as poor curative effect, and stable without new bone and remodeled with new bone were considered to be effective. The vertical distance of the condylar height was measured and compared before and after treatment in the two groups. Results: Significant difference in treatment outcome was found in types Ⅰ and Ⅱ between the splint group and the control group (Z=-2.874, P=0.004; Z=-3.874, P=0.000), and no significant difference was found in type Ⅲ between the two groups (Z=-0.617, P=0.537). The difference of condylar progression percentage [splint group: 43% (15/35), control group: 80% (16/20)] was statistically significant between the two groups in type Ⅱ (χ(2)=7.139, P=0.011), and no significant difference was found in types Ⅰ and Ⅲ between the two groups (χ(2)=0.103, P=0.748; χ(2)=1.249, P=0.540). In two groups, the condylar height difference before and after treatment in type Ⅱ condylar resorption was statistically significant (P<0.05). Conclusions: Stabilization splint treatment was effective in patients with different types of juvenile condylar resorption, especially in type Ⅰ. However, it was difficult to reverse the height reduction of the condylar bone regardless of treatment.