View clinical trials related to Prognathism.
Filter by:Bicortical screws have been widely used for mandibular osteosynthesis during orthognathic surgery.Transoral placement of bicortical screws is a rigid fixation method in orthognathic surgery, which is less often used. The aim of this study was to compare postoperative outcome of transoral versus transbuccal bicortical screw placement during orthognathic surgery. This study comprises an academic, retrospective, monocentric study in which the charts of orthognathic patients operated between January 2010 and December 2012 were retrospectively reviewed. Postoperative complications were registered. Demographic, dental and surgical parameters are examined as potential risk factors for the occurence of postoperative complications.
An in vivo study evaluating the efficacy of the Tandem appliance in the treatment of maxillary deficiency in growing patients compared to the conventional facemask appliance treatment. Pre-treatment and post-treatment lateral cephalograms will be taken. Dentofacial, sagittal and vertical skeletal measurements will be taken at three assessment times. Changes within each group will be assessed. In addition, the changes between the two groups will be compared.
To evaluate the effectiveness in the use of an educational material through: Assessment of knowledge about post-operative orthognathic surgery; assessing levels of anxiety with the survey of Anxiety Inventory-STATE-TRAIT; clinical evaluation of self-care in the management of postoperative signs and symptoms
Deliberate hypotension is defined as lowering the systolic blood pressure to 80-90mmHg, or the mean blood pressure to 50-65mmHg. This technique is usually employed for operations that have a high risk of intraoperative hemorrhage, such as orthognathic surgery. Several different regimens are used to lower the patient's blood pressure, such as vasodilators, autonomic nervous system inhibitors, opioids and inhalation anesthetics. However, the effects that these agents have on the QTc and Tp-e intervals during deliberate hypotension is not known. Virtually every kind of anesthetic is reported to have some effect on the QTc and Tp-e intervals. Because orthognathic surgery usually takes 3-4 hours to complete, the amount of anesthetics and drugs used to maintain low blood pressure is not small. Therefore, the effect that these agents may have on the QTc and Tp-e intervals may not be negligible. The investigators of the present study found that the high dose of commonly used hypotensive agents tend to prolong these variabilities to some extent. This study will be able to provide insight as to which hypotensive anesthesia regimen has the least effect on the QTc and Tp-e intervals, and therefore will be helpful in minimizing cardiovascular risks of deliberate hypotensive anesthesia.
Orthodontic treatment requires application of force systems to individual teeth or groups of teeth, which results in a cellular response with periodontal ligament (PDL) and alveolar bone remodeling. The forces applied must be of sufficient magnitude and duration to exceed the normal physiologic threshold associated with daily oral function. Excessive force levels will result in areas of tissue necrosis with delayed tooth movement and increased risk of root resorption. Although orthodontic tooth movement is achieved in a large segment of the population, the optimum force level has not been defined. The optimum force for tooth movement depends on individual root geometry as well as biologic characteristics of surrounding tissue including bone density, periodontal thickness, and fluid dynamics. Because experimental and clinical techniques are generally limited to known complex force systems, biomechanical modeling has become a necessity. Such models must be validated with well-controlled clinical studies that evaluate orthodontic tooth movement over an extended distance. The ultimate goal would be development of a computer simulation model to predict tooth movement in the clinical setting. The primary objective of this study is to test controlled clinical data with a biomechanical model of the tooth and supporting tissues for distal movement of the human maxillary canine tooth (of known root geometry) in response to various 3D force systems that produce different levels of stress in the supporting tissues. Secondary objectives include evaluation of rate of bodily tooth canine movement with two known compressive stress levels (13 and 22 kPa), evaluation of three different reference systems to measure rate of tooth movement, and evaluation of an implant placed in the roof of the mouth (palatal implant) for orthodontic anchorage in adolescent patients. The rate of translation (bodily) tooth movement of the maxillary canine tooth will be significantly greater with 22kPa compared to 13kPa compressive stress applied to the periodontal ligament, and this difference can be predicted by appropriate mathematical/numerical models of the tooth and supporting tissues.