HEAD AND NECK SURGERY Temporomandibular Joint Dislocation Reduction Technique A New External Method vs. the Traditional

Abstract: The traditional intraoral approach for temporomandibular joint dislocations reduction, although effective, has some disadvantages. Here, a new extraoral approach is described. This study was performed to evaluate this new method's success rate. Patients visiting an emergency room were randomly allocated to 2 groups; one group was reduced with the extraoral approach and the other with the intraoral method. Among 29 attempts with the conventional method, 25 were successful (86.2%; 95% confidence interval: 73-100) and among 29 attempts with the external method, 16 were successful (55.2%; 95% confidence interval: 39 -79). This difference was statistically significant. Because of the benefits of the external approach, such as avoiding hand bites and disease transfer, it can be a reasonable choice to reduce a dislocated temporomandibular joint. Key Words: temporomandibular joint, reduction, extraoral approach, TMJ dislocation (Ann Plast Surg 2009;63: 000 -000) T he most common type of temporomandibular joint (TMJ) dislocation is acute episodes of anterior dislocation, although dislocations may occur in any direction with various associated fractures. 1 Dislocations are usually spontaneous and may result from excess mouth opening in case of yawning, laughing, taking a large bite, seizure, or intraoral procedures such as tooth extraction or orotracheal intubation. Treatment depends on patient status and varies from simple reduction to surgical intervention. The latter is usually necessary only for chronic recurrent and chronic persistent dislocations 2 and in acute forms nearly all cases are managed by hand reduction. The traditional intraoral reduction method, although effective, has some disadvantages: it requires a great effort, especially in patients with strong mastication musculatures 1 ; local or systemic analgesics and muscle relaxants or sedatives are necessary occasionally; risks of bite injury regarding hepatitis, AIDS, syphilis, or other transmittable diseases; and patient discomfort regarding the physicians hand in his/her mouth. Therefore, another method using an extraoral approach always has been a concern. 3,4 The external method introduced by Chen et al is supposed to be an easy and effective way to reduce TMJ dislocation, as they stated. 3 Therefore, we performed this study to evaluate the success rate of this new method in comparison to that of the traditional method. METHODS Amir-A'lam General Hospital is a tertiary center for otolaryngology diseases in Iran. Patients referring to the emergency room (ER) were included consecutively in this prospective trail in an 8-month period (January-August 2007). Procedures were performed by second-year otolaryngology residents with a good level of experience in both techniques, who had performed a large number of under-observation reductions before the study. Block randomization was used for allocating patients into 2 different modality groups. ER reception was provided with a list of random blocks of 2. Every patient, before entry to the clinic and visited by ER physicians, was coded to enter to one of the treatment groups. Therefore, both the patients and the reducing physician were not aware of patient allocation. A thorough history was taken regarding demographic information, past history of general ligament laxity, past history of TMJ dislocation, underlying disorders, trauma, prior use of muscle relaxing agents, and time delay between dislocation and reduction. Mandible fractures especially those involving the condylar and subcondylar region were ruled out by physical examination and proper x-rays when needed. To reduce TMJ dislocation, the patient was put in either a sitting or supine position and the operator sat or stood in front of the patient. An attempt was made to reduce the dislocation using the randomly chosen method. The success rate was calculated regarding successful patient treatment for each method on the first try. As the salvage for the unsuccessful cases if the first method failed, the other method was attempted and if that too was not successful, a muscle relaxant (10 mg diazepam) was administered and the TMJ dislocation was reduced. To avoid patient cross over between groups these second reductions were not included in the analysis. Conventional Method The physician, applying bimanual intraoral force on the mandibular molars of the patient in an inferior and then posterior direction, will reduce the dislocated condyle back into the glenoid fossa. New Method 3 The physician places one hand on each of the patient's cheeks. On one side, the thumb is placed just above the anteriorly displaced coronoid process, and the fingers are placed behind the mastoid process to provide a counteracting force. On the other side, the fingers hold the mandible angle and the thumb is placed over the malar eminence. To reduce the dislocated jaw, one side of the mandible angle is pulled anteriorly by the fingers, with the thumb over the malar eminence acting as a fulcrum. While the mandible angle is pulled anteriorly, steady pressure is applied on the coronoid process of the other side, with the fingers behind the mastoid process providing counteracting force. The mandible is rotated by this maneuver and the dislocated TMJ is usually reduced on one side. Once one side of the dislocation is reduced, the other side will usually go back spontaneousl

MicroRNA expression patterns unveil differential expression of conserved miRNAs and target genes against abiotic stress in safflower.

Environmental stresses influence the growth and development of plants by influencing patterns of gene expression. Different regulators control gene expression, including transcription factors (TFs) and microRNAs. MicroRNAs (miRNAs: ~21 nucleotides long) are encoded by miRNA genes transcribed by RNA polymerase II (RNP-II) and play key roles in plant development and physiology. There is little knowledge currently available on miRNAs and their function in response to environmental stresses in safflower. To obtain more information on safflower miRNAs, we initially used a comparative genomics approach and succeeded in identifying 126 miRNAs belonging to 29 conserved families, along with their target genes. In this study, we investigated the expression profiles of seven conserved miRNAs related to drought, salinity, heat, and Cd stress in the leaf and root organs using qRT-PCR, for the first time. Gene Ontology (GO) analysis found that target genes of miRNAs are often TFs such as AP2/ERF and HD-ZIP as well as NAC domain-containing proteins. Expression analyses confirmed that miRNAs can play a vital role in keeping safflower stress-tolerant. Differential expression of miR156, miR162, miR164, miR166, miR172, miR398, and miR408 regulate the expression of their respective target genes. These genes activate several pathways leading to physiological and biochemical responses to abiotic stresses. Some conserved miRNAs were regulated by abiotic stresses. Our finding provides valuable information to understand miRNAs in relation to different abiotic stresses in safflower