Clinical Research Directory

Comparison of Early Interceptive Orthodontic Appliances (Traditional and Novel) and Later Fixed Appliance Treatment in Class II Malocclusion.

Background Approximately 15% of children have a Class II malocclusion, where the maxilla is positioned anterior to the mandible, and around 90% of these children also present with an increased overjet. Increased overjet is associated with a higher risk of dental trauma and psychosocial consequences such as bullying and reduced oral health-related quality of life (OHRQoL). Functional orthodontic appliances (e.g., headgear-activator and Twin-block) have long been used to reduce overjet through dentoalveolar effects and by influencing mandibular position and growth. More recently, digital solutions such as Invisalign's mandibular advancement appliance have been introduced, with potential advantages including improved wear time and simultaneous tooth alignment. However, there is currently limited evidence regarding treatment outcomes, patient experience, and cost-effectiveness of these newer appliances compared with established functional appliances. Aim The primary aim is to compare treatment outcomes, patient experience, and cost-effectiveness of interceptive orthodontic treatment using three different appliances. The overall aim is to determine whether interceptive treatment of Class II malocclusion with large overjet is effective, and if so, which interceptive modality should be preferred. Study design and setting A total of 144 patients aged 9-13 years with Class II malocclusion and large overjet will be randomized into four groups: * Headgear-activator * Twin-block * Aligner Mandibular advancement * Control Participants will be treated at four Orthodontic Specialist Clinics within the National Health Service in Region Halland and Västra Götaland, Sweden. Treatments will be provided by two experienced orthodontic specialists. Follow-up and data collection Clinical examinations will be performed at: * Baseline (T0) * 9 months into treatment (T1) * End of treatment (T2) Appliance checks will occur every 8 weeks. Digital scans of the occlusion will be collected at T0, T1, and T2. Lateral cephalometric radiographs will be taken at T0 and T2. Outcomes and planned analyses The trial will generate three studies with distinct outcomes: 1. Treatment outcomes Primary outcome: dental treatment effectiveness measured as overjet reduction. Secondary outcomes: other dental variables, skeletal outcomes, and extraoral outcomes. 2. Patient-reported outcomes All treated patients will complete two digital questionnaires: * Child Perception Questionnaire (CPQ): assesses the child's perception of their teeth before and after treatment. * Orthodontic Treatment Impact Questionnaire (OTIQ): assesses the child's experience of orthodontic treatment and the appliance. These outcomes will be used to evaluate changes in OHRQoL from pre- to post-treatment and to compare experiences across treatment modalities. 3. Cost-effectiveness analysis The economic evaluation will include direct, indirect, and societal costs. Treatment duration, number and length of appointments, and cancellations/no-shows will be recorded. * Direct costs: premises, staff salaries, materials, and laboratory costs. * Indirect costs: parental loss of income due to absence from work. * Societal costs: direct + indirect costs. Costs will be related to treatment outcomes to estimate cost-effectiveness across the treatment arms. Additional comparison: early vs late treatment Furthermore, after completing 18 months the control group, and half of the functional appliance patients will receive treatment with fixed appliances. This enables an additional comparison of early interceptive treatment versus later treatment using the same outcomes: treatment effectiveness, patient-reported outcomes, and cost-effectiveness.

The Effectiveness of the Twin Block and Carriere Motion Appliances in Post-pubertal Patients and an Evaluation of the Impact of Class II Malocclusion and Its Correction on Oral Health-related Quality of Life

The investigators of this clinical trial aim to: * Compare the effectiveness and efficiency of Clark's Twin Block Appliance (CTB) vs Carriere Motion Appliance (CMA) in correcting Class II malocclusion when used in post-pubertal older adolescents, in terms of skeletal and dental change. * Evaluate potential negative oral health-related quality of life (OHRQoL) impacts during the active treatment phase with either CTB or CMA in post-pubertal adolescents. * Investigate the impact of Class II malocclusion on oral health-related quality of life (OHRQoL) in post-pubertal adolescents. Class II division 1 malocclusion is a dental condition where the upper teeth protrude significantly over the lower teeth. It is a common type of malocclusion observed in orthodontic practice, accounting for approximately 20-25% globally. Correcting Class II malocclusion in growing patients using functional appliances and Class II correctors is relatively predictable. In Ireland and the United Kingdom, the Clark's Twin Block (CTB) is the most commonly used functional appliance. The CTB consists of two components: one for the upper teeth and one for the lower teeth. These components are engineered to position the lower jaw forward, thereby promoting the desired dentoskeletal changes (moving the upper teeth back and lower forward). Another device used for Class II correction is the Carriere Motion Appliance (CMA). The CMA is gaining popularity as a treatment option for Class II malocclusion, inducing dental changes similar to those achieved with a CTB. However, uncertainty persists regarding the effectiveness of these appliances in older adolescents in the post-pubertal growth phase (aged approximately 14.5 years or above). Additionally, although both CTB and CMA are effective in growing patients in correcting dental and skeletal discrepancies, they may influence daily activities, comfort, and psychological aspects, which often results in poor compliance. Poor adherence to orthodontic treatment, whether with fixed or removable appliances, can lead to higher rates of treatment failure.

Mandibular Advancement Planning Based on Clinical Overjet

This Prospective study aims to simulate the maximum mandibular advancement in class II patients treated by Herbst MTH Appliance on the base on clinical overjet. Initial intraoral scans will be uploaded in Suresmile software, the upper incisors will be virtually aligned and the mandible will be advancement until an anterior occlusal contact will be reached. This virtual advancement will be compared to the real advancement obtained at the end of the Herbst phase. This protocol will be applied to two groups: one with traditional dental occlusion, the second one with Skeletal anchorage reinforcement and elastic chains