Active clinical trials for "Retrognathia"

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.

Distraction osteogenesis is a powerful technique for creating new bone during significant lengthening of the mandible without the need for bone grafting and associated donor site morbidity. The idea of distraction osteogenesis was largely abandoned by many until the 1950s. Ilizarov minimized complications by performing a corticotomy with minimal disruption of the surrounding blood supply and using a system of tension ring fixators to control the distraction in multiple planes. Through a series of experimental studies and clinical applications, Ilizarov established the foundation of distraction osteogenesis and its role in orthopedic management. Applications in craniofacial surgery were first seen in 1973, when Synder et al applied the approach to mandibular lengthening in a canine animal model. Almost another 20 years passed before McCarthy and colleagues published, in 1992, the first report of mandibular lengthening in 4 children with congenital mandibular deficiency, 3 with hemifacial microsomia, and 1 with Nager syndrome. Thereafter, its role rapidly expanded to the midface and nearly all classic approaches to craniofacial reconstruction. In general, mandibular distraction can be performed in the ramus for ramus lengthening, in the mandibular angle for downward and forward advancement, or in the mandibular body. Ramus or gonial angle distraction are mainly used to treat facial asymmetries as in hemifacial macrosomia. Severe mandibular retrognathia can be classified as congenital or acquired. Congenital abnormalities that are associated with severe mandibular retrognathia or micrognathia include craniofacial syndromes such as hemifacial microsomia, Pierre-Robin syndrome, Treacher-Collins syndrome, and Nager syndrome. Adult patients with craniofacial syndromes may have undergone previous surgery at an earlier age, but unfavorable postsurgical growth or skeletal relapse may have occurred. Severe mandibular retrognathia also can develop following maxillofacial trauma and mandibular fractures, which may have occurred in an adult or as a child Condylar fractures occurring at an early age can result in subsequent bony and/or fibrous temporomandibular joint ankylosis and/or deficient mandibular growth, also adult patients with complications from previous mandibular tumor resection and reconstruction can also present with acquired severe mandibular retrognathia that may require distraction osteogenesis as well. Despite the advantages of extra-oral distraction devices in the hands of clinicians (application for very small children, simplicity of attachment, ease of manipulation, bidirectional and multidirectional dis- traction), patients are apprehensive about wearing bulky external appliances because of the social inconvenience and the potential of permanent facial scars, these disadvantages and limitations were the primary force driving the evolution of mandibular lengthening and widening toward the development of intra-oral devices. However nowadays both internal and external distractors are used in a variety of indications in these cases each of the two types of distractor devices has its own advantages and disadvantages. Aim of the work: The aim of this study is to compare external and internal distraction devices for mandibular lengthening in terms of bone lengthening, patient comfort, and complications.

The aim of this study is to compare to different protocols to treat Class II malocclusion in growing subjects using the twin block appliance

For improving the appearance of protruded upper front teeth when lower front teeth may touch palatal mucosa or have proximity to that; the innovated Seifi's Functional Appliance may be used.

This study is to measure the eshetic outcome of of isolated advancement genioplasty with and without submental liposuction in treatment of skeletal chin deficiency in double chin patients

Prospective, randomized, double-blind, placebo-controlled, mono center, Phase III trial to compare EXACYL in preventive with placebo on perioperatory bleeding in orthognathism surgery.

Differences in nasotracheal intubation pathway anatomy will be observed between healthy patients and patients with maxillary retrusion. The results will clarify the nasotracheal intubation tube preference for these patients.

To compare dentoskeletal changes in patients with skeletal class II malocclusion induced due to treatment with orthodontic appliances; removable twin block appliance and fixed AdvanSync2 appliance in two different age group patients.

The aim of this prospective study is to analyze the postoperative paresthesias experienced in patients who undergo bilateral sagittal split osteotomies (BSSO) using an ultrasonic saw, versus a reciprocating saw. Patients included in the study are ages 15-45 scheduled to undergo BSSO surgery at the University of California, San Francisco. One side of the patient's mandible will be instrumented with either the Stryker Sonopet ultrasonic saw or traditional reciprocating saw, while the other side will receive the remaining intervention (determined via randomization on the day of surgery). Patient paresthesias will then be analyzed on each side for 3 months postoperatively (at postoperative days: 1, 7, 14, 28, and 84). Sensory examinations will be carried out by blinded examiners using von Frey hairs and two point discrimination testing. Patients will also subjectively rate their sensation on each side. The results will then be analyzed to determine if patient paresthesias, including the severity and duration, differed depending on which instrument was used, the ultrasonic or reciprocating saw.

The aim of this study is to evaluate the effect of Intravenous iron isomaltoside on maintaining hemoglobin concentration in patients undergoing bimaxillary orthognathic surgery. Fifty-eight patients, aged 19 to 40 years, scheduled for Bimaxillary orthognathic surgery will be divided into monofer (n=29) and control (n=29) groups. Randomly selected patients of the ulinastatin group are given intravenous iron isomaltoside. In contrast, patients in the control group receive an equivalent volume of normal saline as a placebo. The primary endpoints are postoperative hemoglobin concentration.