Dixith S Aishwarya, K R Chaitra, Shyagali Tarulatha R, K Vinay, Shetty Smitha V, D Sindhu, M Veekshith, R Sukrutha
Department of Orthodontics, Mathrusri Ramabai Ambedkar Dental College and Hospital, Bangalore, IND.
Cureus. 2025 Aug 10;17(8):e89762. doi: 10.7759/cureus.89762. eCollection 2025 Aug.
Introduction Skeletal Class II malocclusion, commonly resulting from mandibular retrognathism, poses both functional and aesthetic challenges in growing patients. Functional orthopaedic appliances, such as the Twin Block, aim to correct this by stimulating mandibular growth through forward positioning. This biomechanical stimulus is believed to trigger adaptive remodelling at the condylar cartilage level, influencing bone formation pathways and playing a crucial role in the release of salivary biomarkers such as osteocalcin, osteonectin, and collagen type 1, which can be non-invasively detected. Aim This study aims to assess the salivary levels of collagen type I, osteocalcin, and osteonectin in skeletal Class II patients undergoing myofunctional therapy with a Twin Block appliance. Methods A total of 10 adolescents aged 8-15 years with skeletal Class II malocclusion were selected and treated with Twin Block appliances. Unstimulated saliva samples were collected at four time points: baseline (prior to appliance insertion) and 15, 30, and 60 days post-insertion. Samples were stored at -82°C and analysed for type I collagen, osteocalcin, and osteonectin using biochemical assays. Results All three biomarkers (collagen type I, osteocalcin, and osteonectin) showed a consistent pattern of expression. Levels increased from baseline and peaked at 30 days, indicating heightened osteogenic activity and extracellular matrix remodelling. By 60 days, a slight decline was observed; however, levels remained significantly elevated compared to baseline, suggesting continued bone adaptation in response to functional stimulation. Conclusion Myofunctional therapy with a Twin Block appliance elicits a measurable biological response indicative of bone remodelling in adolescents with skeletal Class II malocclusion. The increase in salivary levels of key osteogenic markers validates the efficacy of functional appliance therapy and highlights the utility of saliva as a non-invasive diagnostic tool for monitoring treatment-induced bone changes.
引言
骨骼II类错牙合畸形通常由下颌后缩引起，给生长发育期的患者带来功能和美观方面的挑战。功能性正畸矫治器，如双阻板矫治器，旨在通过前伸定位刺激下颌生长来纠正这种情况。这种生物力学刺激被认为会在髁突软骨水平引发适应性重塑，影响骨形成途径，并在唾液生物标志物如骨钙素、骨连接蛋白和I型胶原蛋白的释放中起关键作用，这些标志物可以通过非侵入性检测得到。
目的
本研究旨在评估使用双阻板矫治器进行肌功能治疗的骨骼II类患者唾液中I型胶原蛋白、骨钙素和骨连接蛋白的水平。
方法
共选择10名8 - 15岁患有骨骼II类错牙合畸形的青少年，用双阻板矫治器进行治疗。在四个时间点收集非刺激性唾液样本：基线（矫治器佩戴前）以及佩戴后15、30和60天。样本储存在-82°C，使用生化分析方法分析I型胶原蛋白、骨钙素和骨连接蛋白。
结果
所有三种生物标志物（I型胶原蛋白、骨钙素和骨连接蛋白）均呈现出一致的表达模式。水平从基线开始升高，并在30天时达到峰值，表明成骨活性增强和细胞外基质重塑。到60天时，观察到略有下降；然而，与基线相比，水平仍显著升高，表明对功能刺激的持续骨适应。
结论
使用双阻板矫治器进行肌功能治疗可引发可测量的生物学反应，表明骨骼II类错牙合畸形青少年存在骨重塑。关键成骨标志物唾液水平的升高验证了功能性矫治器治疗的有效性，并突出了唾液作为监测治疗引起的骨变化的非侵入性诊断工具的实用性。
