جستجوی مقالات مرتبط با کلیدواژه "ligation" در نشریات گروه "پزشکی"

One side effect of orthodontic treatment is microcrack formation during debonding process. Since the type of ligation may affect the applied debonding force, this study was conducted to investigate the effect of ligation method on the enamel microcrack formation following debonding of orthodontic brackets.

The present study was an experimental in vitro study. 69 extracted human premolar teeth were divided into 3 groups with 23 teeth by a simple random method. A bracket was bonded on the buccal surface of the teeth, then the desired tooth was placed in a typodont where the rest of the teeth were mounted. Then, the arch wire was passively placed in the bracket slot. The samples were ligated by one of these three methods based on the study group: 1. Oring ligation 2. Tight ligation with a wire ligature for each tooth separately 3. Ligation of all arch teeth together, using a wire ligature. The buccal surfaces of the teeth were observed under a stereomicroscope and the length, location, and the number of microcracks were recorded before and after debonding process. In order to analyze the data, generalized estimating equation analysis was used.

In all three groups, a significant increase was observed in the average total length and number of enamel microcracks following the debonding process. (P<0.001 in all three groups), with no statistically significant difference between the three study groups. However, it was greater in group 2 than that of groups 3 and 1 respectively. In general, the number of new cracks was more in mid-buccal area followed by cervical and occlusal areas.

The debonding process caused an increase in the average total length as well as the number of enamel microcracks. Type of ligation might affect the enamel microcrack formation so that in tight ligation group we had the greatest increase in the enamel damage especially in mid-buccal area of the tooth. Tight ligation method can cause more enamel cracks than O-ring ligation and full arch ligation methods.

This study aims to investigate the effect of spinal nerve ligation (SNL) after a period of combined training on the expression of some genes that are involved in the calcium flow in the plantaris muscle of male Wistar rats. 

A total of 16 adult male Wistar rats were randomly divided into 2 groups, namely the control-SNL (n=8) and combined training-SNL (n=8). The animals in the training group participated in a training program for 6 weeks. After this period, the protocol of spinal SNL was performed on the research groups for 4 weeks. Finally, the rats were dissected and the plantaris muscle was removed. Real-time polymerase chain reaction was used to measure the mRNA expression of STIM1, ORAI1, and MG29 genes. 

In the combined training-SNL group, an increase in the expression of STIM1 (P=0.01), ORAI1 (P=0.002), and MG29 (P=0.02) was observed when compared to the control-SNL group. 

The results of the present study showed that SNL reduces the expression of STIM1, ORAI1, and MG29 in the plantaris muscle. Meanwhile, combined training before SNL has a compensatory effect in this regard.

Severe arterial injuries in the hand can be hazardous to the limbs and even life- threatening. The aim of this study was to investigate the management methods in the patients with acute injuries of the ulnar or radial artery in the emergency department. This cross-sectional prospective study was conducted in the emergency department of Sina Hospital in Tehran, from 2012 to 2013. Stable vital signs, wrist and forearm laceration with jumper or active bleeding, radial or ulnar artery injury; one or both were among our inclusion criteria. Vital signs, level of consciousness, coincident injuries were assessed and physical examination was performed in all patients. We recorded time of patient arrival, primary and secondary treatment, and consultation and follow up visits in emergency department or ward. 50 patients (3 females and 47 males) with a mean age of 30.34y ± 9.69y were enrolled. The first step was to examine and pack up bleeding. The most common injury was due to sharp instruments (84%) and the most common injured artery was radial artery (68%).The mean duration of the first treatment was 1.24 ± 0.93 min. 37 patients (74%) were treated by ligation in the emergency room and the remaining 13 patients (26%) were sent to the operating room for repair and vascular anastomosis by our vascular surgeon. Mean values of duration for ligation were 16.72 ± 13.83 min and 117.76 ± 114 min in emergency medicine and vascular surgery groups, respectively that showed a significant difference between the two groups (p= 0.0001). The overall duration of hospitalization for the patients was 69.04 ± 82.74 hour (5- 311 hours). We can conclude that the radial or ulnar artery ligation considering its indications or contraindications, in emergency room can play an important role in the recovery of patient's hemodynamic status and speed up of the next step of patient’s treatment.