Individuals with Class II malocclusion and hyperdivergent skeletal dysmorphology (C2HYP) are among the most difficult patients to treat orthodontically. Current treatment approaches, while effective for correcting dental malocclusions, do not adequately address the skeletal and soft-tissue treatment objectives. Our goal is to determine the feasibility of a novel treatment approach that relies on mandibular rotation to correct dysmorphology. Our novel and simple treatment approach uses mini-screw implants (MSI) to intrude the posterior teeth, it requires minimal patient compliance, and it is expected to produce a large treatment effect. Based on a sample of 20 adolescents, this study will determine whether our novel approach holds promise for treating C2HYP adolescent patients.
The first aim i s to determine whether MSI's can be successfully used to rotate the mandible, advance the chin, and improve lower facial profile. True mandibular rotation will be measured longitudinally after superimposing on naturally stable mandibular reference structures. We expect to produce several degrees of forward mandibular rotation, which is in turn expected to produce improvements in chin position and lower face height.
The second aim of this project is to determine whether MSI's can be successfully used to intrude posterior segments of teeth without tipping them. Intrusion will be measured radiographically after superimposing on naturally stable reference structures in the mandible and maxilla. Tipping will be measured directly from dental models and 3D ICAT images.
The third aim i s to determine whether posterior teeth intruded with MSI's exhibit greater than expected amounts of root resorption. Root resorption will be measured longitudinally using standardized periapical radiographs.
The fourth aim i s to determine whether MSI's remain stable and are tolerated throughout the course of treatment. Stability will be evaluated qualitatively at regular intervals. The patients' tolerance will be assessed using questionnaires. In response to RFA-DE-06-007, this R21 application is submitted as a Clinical Pilot Data Grant under NIDCR's Clinical Trials Program and is intended to establish the feasibility of our novel treatment approach. ? ? ?
| Buschang, Peter H; Carrillo, Roberto; Rossouw, P Emile (2011) Orthopedic correction of growing hyperdivergent, retrognathic patients with miniscrew implants. J Oral Maxillofac Surg 69:754-62 |
