Expression of Biomarkers “Lubricin and Proliferating Cell Nuclear Antigen” in Rat Mandibular Condylar Cartilage Following Advancement and Post-Removal Recovery

Aim: The mandibular condylar cartilage (MCC) plays a pivotal role in mandibular growth modification during orthodontic functional appliance therapy. This study aimed to evaluate the expression of Lubricin and proliferating cell nuclear antigen (PCNA) in rat MCC following mandibular advancement and after a recovery period post-appliance removal.Methods: Thirty male Wistar rats (۶–۸ weeks old) were divided into three groups (n=۱۰ each): control (Group A), appliance (Group B), and appliance + recovery (Group C). A mandibular advancement appliance was fitted to Groups B and C for one month; Group C underwent an additional one-month recovery period. Mandibular condylar tissues were collected for histopathological evaluation and biomarker quantification using ELISA. Statistical analyses were performed using ANOVA and post hoc Tukey tests with significance set at P<۰.۰۵.Results: Both PCNA and Lubricin concentrations were significantly higher in Groups B and C compared to the control (P<۰.۰۵). Mean PCNA levels were ۵۹.۶۵ ± ۷.۳۹ ng/mL (A), ۸۱.۲۱ ± ۳.۴۲ ng/mL (B), and ۷۵.۰۶ ± ۹.۱۵ ng/mL (C). Lubricin concentrations followed a similar trend: ۲۰۰.۸۱ ± ۴۸.۲۱ ng/mL (A), ۳۱۹.۴۳ ± ۱۹.۲۸ ng/mL (B), and ۲۷۴.۳۵ ± ۴۰.۴۳ ng/mL (C). Histomorphometric analysis revealed increased proliferative layer thickness in Group B and greater hypertrophic layer thickness in Group C, indicating adaptive remodeling after appliance removal.Conclusion: Functional appliance therapy induced significant upregulation of PCNA and Lubricin in the MCC, reflecting enhanced cellular proliferation and joint adaptation. Although biomarker expression decreased after appliance removal, it remained elevated compared to controls, suggesting a residual stimulatory effect on mandibular growth and cartilage remodeling.

کلیدواژه ها:

Functional appliance ، Enzyme-Linked Immunosorbent Assay ، Mandibular Condyle Cartilage ، Lubricin ، Proliferating Cell Nuclear Antigen