Experimental study on firearm wound in maxillofacial region. (1/25)

OBJECTIVE: To make clear the range of firearm wound in the maxillofacial region, the optical repair time and the characteristics of accompanied indirect brain damage, and to offer the principle of emergency treatment and the early repair of war wound. METHODS: With the aid of the standard Sweden model, 200 dogs were used in the experiment. Varies tissues around the primary canal were harvested chronologically, in different zone and different tissue, for histopathological examination. RESULTS: The necrotic range of various tissues in the maxillofacial region was less than that in the extremities. In the maxillofacial region, there was a significant temporary cavity following the passing of bullet, which caused indirect brain damages. CONCLUSION: These findings are helpful to the treatment of war wound in the maxillofacial region. Early bone transplantation using microvascular anastomosis in the treatment of gunshot wound in the maxillofacial region is recommendable.  (+info)

The biochemical study of intermaxillary fixation (IMF) stress in oral surgery inpatients. (2/25)

Although intermaxillary fixation (IMF) is performed to treat the patients with maxillary fracture, this procedure is very stressful to the patients. IMF has been reported to increase noradrenaline (NA) release in the brain and elevate plasma corticosterone contents in the rat. These changes were significantly attenuated by diazepam, an anxiolytic of the benzodiazepine family. These results suggest that IMF could greatly affect the pituitary-adrenal system as a stress. In the present study, in order to examine the influence of IMF on the human body function, we measured levels of 17-hydrocorticosteroids (17-OHCS) and 17-ketosteroid (17-KS), which are metabolites of the adreno-cortical hormone cortisol, in the urine of inpatients undergoing IMF. The subjects were requested to fill out a questionnaire on irritableness caused by IMF. In these patients, urinary 17-OHCS levels were significantly increased after IMF and well correlated to the results of the questionnaire. The finding suggested that urinary 17-OHCS levels reflect stress related to IMF, and that such stress mainly causes an irritated feeling. Natural killer cell activity (NK activity), which is considered to be related to stress, was measured in these patients. The relationship between 17-OHCS levels and NK activity was examined in reference to the results of the questionnaire. Questionnaire showed that most patients noted insomnia and an irritated feeling during IMF. To examine the influence of anxiolytic agents on stress related to IMF, an anxiolytic agent, ethyl loflazepate, was administered during IMF, and urinary 17-OHCS levels were measured. There was no correlation between 17-OHCS levels and NK activity in the patients. Furthermore, no correlation was observed between visual analogue scale (VSA) and NK activity. Increases in 17-OHCS levels in the group treated with ethyl loflazepate, an anxiolytic of the benzodiazepine family, were significantly lower than in the untreated group. This suggests that ethyl loflazepate reduced stress responses to IMF. It has been reported that NK activity is reduced inpatients with depression or chronic fatigue syndrome. However, NK activity may not be affected by mechanical stress such as IMF. The finding that an anxiolytic agent, ethyl loflazepate, inhibited stress responses to IMF further suggests that anxiolytic drugs are very useful for treatment of irritated feeling of the patients undergoing IMF.  (+info)

Human maxilla bone response to 30 degrees oriented impacts and comparison with frontal bone impacts. (3/25)

The aims of this study were to compare the responses of human maxilla and frontal bones under 30 degrees-oriented impacts. Maxilla and frontal bones of the same subject were impacted by a guided horizontal steel cylinder. Linear acceleration time histories and force time histories were plotted and corridors were proposed for maxilla bone response. Sensitivity of head dynamics in regard to impact energy level and localization showed the protection of the intracranial contents by the facial bones crushing. Injury risk curves were established for impact on frontal bone, showing a 50% risk injury for impact energy of 265 J or impact force of 7500 N.  (+info)

Antibiotics in orbital floor fractures. (4/25)

A short cut review was carried out to establish whether prophylactic antibiotics are indicated in patients with undisplaced maxillary or orbital floor fractures. Altogether 214 papers were found using the reported search, but none presented any evidence to answer the clinical question. More research is needed in this area and, in the mean time, local advice should be followed.  (+info)

The application of virtual endoscopy with computed tomography in maxillofacial surgery. (5/25)

OBJECTIVE: To use virtual endoscopy to obtain detailed three-dimensional images of bone, soft tissue and paranasal sinus damage as well as images of adjacent unaffected areas for optimum surgical planning. METHODS: A spiral CT scanner was used to examine 46 cases of facial bone fractures, maxillary cysts, obstructive sleep apnea syndrome (OSAS) and maxillary bone tumours. Data were input into a navigator workstation to create images similar to those displayed by a fiberoptic endoscope. Various 3-D images were obtained when probe sites were changed. RESULTS: Virtual endoscopy can clearly display the anatomic structure of the paranasal sinuses, nasopharyngeal cavity and upper respiratory tract, revealing damage to the sinus wall caused by a bone tumor or fracture. In addition, the technique can be used to indicate volume changes of the upper respiratory tract in OSAS patients. These results were similar to those obtained through actual operations. CONCLUSIONS: Virtual endoscopy is a new method which produces very clear images. It is reliable to provide detailed information for optimal operative planning.  (+info)

Hemodynamic effect of propofol in enalapril-treated hypertensive patients during induction of general anesthesia. (6/25)

Angiotensin converting enzyme inhibitor (ACE-I) treated hypertensive patients are well known to be at risk during general anesthesia, because of hypotension that can occur. We compared hemodynamic changes in these patients during induction of general anesthesia with propofol and etomidate - two intravenous anesthetics. Hypotension after propofol that we observed in ACE-I group versus normotension after etomidate (p < 0.001) in our opinion may be the result of additive effect of similar endothelium-dependent mechanism of action of propofol and ACE-I, i.e. increase in production and release of nitric oxide (NO). This very unique observation, however, needs further investigation to precisely define the mechanism of our finding.  (+info)

An ultrastructural study on indirect trauma of dental pulp caused by maxillofacial impact injury in dogs. (7/25)

BACKGROUND: Indirect injuries of adjacent tissues and organs usually accompany maxillofacial impact injuries. However, studies on indirect dental pulp injury are rare. This study was designed to determine the characteristics of indirect dental pulp injury caused by impact injury of mandible in dogs. METHODS: Eighteen dogs were divided equally into six groups with random allocation. Right mandible of each dog was impacted but teeth were not injured directly. Then, the animals were killed at appointed time points and ultrastructural changes in dental pulp of assigned teeth of each dog were investigated with transmission electron microscope. RESULTS: Dental pulp of the fourth premolar of right mandible was injured very severely, but irreversible necrosis did not occur in the end. Dental pulp of the second premolar of right mandible was injured less severely and reversibly. Dental pulp of the second premolar of left mandible was injured mildly and temporarily. CONCLUSION: In the indirect injury of dental pulp caused by maxillofacial impact injury, the injured area is relatively extensive. The effect of the trauma decreases progressively and sharply as the distance to the impact site increases. Ultrastructural changes in the damaged nerves take place early.  (+info)

Management of facial trauma in children: A case report. (8/25)

Children are uniquely susceptible to cranio facial trauma because of their greater cranial mass to body ratio. Below the age of 5, the incidence of pediatric facial fractures in relation to the total is very low ranging from 0.6-1.2%. Maxillo-facial injuries may be quite dramatic causing parents to panic and the child to cry uncontrollably with blood, tooth and soft tissue debris in the mouth. The facial disfigurement caused by trauma can have a deep psychological impact on the tender minds of young children and their parents. This case report documents the trauma and follow up care of a 4-year-old patient with maxillofacial injuries.  (+info)