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91.
92.
An antibody-capture radioimmunoassay was used to measure levels of IgG class antibodies to rubella and hepatitis A viruses in serum and saliva of 30 edentulous, 30 partially dentate and 31 dentate individuals. The prevalence of seropositivity for rubella was 98.9 per cent and for hepatitis A 73.6 per cent. The serum reactivities were generally greater than those for saliva. There were 8 false-negative results for saliva out of the 182 tests performed, of which 4 were in the edentulous group, 3 in the partially dentate and 1 in the dentate group. For both rubella and hepatitis A virus antibodies the (geometric) mean ratios between the saliva and serum reactivities were similar across the three dental groups. The values for sensitivity, specificity and positive predictive value suggest that assay of saliva for antiviral IgG antibody is a satisfactory technique regardless of dental status.  相似文献   
93.
An analysis by scanning electron microscopy was undertaken to investigate the effects of bleaching on enamel-cementum surface morphology. Teeth were investigated in five groups: control; vital bleached for 5, 15, and 30 days; and 37 percent phosphoric acid gel etched for 20 seconds. Only the gel-etched group exhibited etching patterns. Shade change in vital bleached teeth was noted in the group vital bleached for 30 days.  相似文献   
94.
An investigation into the pattern of complaints lodged by patients after impacted mandibular third molar surgery was done in a Nigerian teaching hospital over a period of 3 years. One hundred and twenty seven records were retrieved. Pericoronitis (71.2%), pulpitis (17.6%) and periodontitis (11.2%) were the reasons for surgery. No third molar surgery was done for prophylactic or orthodontic reasons. Sixty-one complaints were lodged by 49 (38.6%) patients on day 1, and 37 complaints by 35 patients on day 7. These complaints were verified by the findings of the examining clinician. Pain, swelling and trismus were the commonest complaints. A significant association (P = 0.042) was found between patients' complaints on the first postoperative day and the drug combination given. Similarly, there was a significant relationship (P = 0.0055) between the type of analgesics prescribed and the presence of postoperative pain. No significant relationship was however found between the complaints and patients' age, indication for extraction, impaction type and method of impacted tooth removal. Although the findings of this retrospective study are limited in their comparability, they suggest the need for an appraisal of pain management in patients undergoing mandibular third molar surgery in our hospital. Consequently, there should be a reduction in complaint rate thereby making selective review appointment on the first postoperative day feasible.  相似文献   
95.
The presence of foreign biological substances in the human body can lead to violent immune reactions. This is the report of a very rare case involving not only the presence of a biological substance, but also a symbiotic relationship between a living plant (the common wheat grain, Triticum aestivum L.) and the human body. Black coal particles and one cereal grain were removed from the subgalea of the right parietal region of a 35-year-old man who had sustained injuries in a motor vehicle accident 16 days earlier. There were signs of germination of the grain, but no macroscopic or microscopic evidence of an inflammatory reaction. Grain germination was verified microscopically. There are various explanations for the absence of an immune reaction, but only coal-tar-induced immunosuppression can explain the observed phenomenon.  相似文献   
96.
Peripheral action of opioids for pain control, for which local inflammation has been shown to be crucial, is being increasingly used in clinical practice. The aim of this study was to evaluate the hypothesis that addition of fentanyl to lidocaine, when injected into inflamed dentoalveolar tissues, can improve the quality of analgesia during surgery. Seventy-one patients reporting with pain and tenderness in the maxillary tooth were assigned into the experimental (LAF) or control (LA) group in a prospective, randomized double-blind trial. The LAF group (n = 36) was injected submucosally with a mixture of 40 microg of fentanyl (0.8 ml) and 2% lidocaine hydrochloride with 1:200000 adrenaline (2 ml). In the LA group (n = 35) 0.9% of saline (0.8 ml) was added instead of fentanyl. The pain scores were recorded before injecting, 5 min after injection, and immediately after surgery using a visual analogue scale. The mean pain scores were not significantly different at all time intervals. Twelve patients in the LAF group (2.75+/-0.72 ml) and ten patients in the LA (2.90+/-0.70 ml) group required additional local anaesthetic to achieve pain control. In conclusion, there was no improvement in quality of intraoperative analgesia on addition of fentanyl to lidocaine in inflamed dentoalveolar tissues.  相似文献   
97.
98.
There is little objective data about whether surgical technique or mandibular anatomy are a risk for inferior alveolar nerve (IAN) injury during bilateral sagittal split osteotomy (BSSO). Orthodromic sensory nerve action potentials (SNAPs) of the IAN were continuously recorded on both sides in 20 patients with mandibular retrognathia during BSSO operation. Changes in latency, amplitude, and sensory nerve conduction velocity (SNCV) at baseline and at different stages of the operation were analyzed. The SNAP latencies prolonged, the amplitudes diminished, and the SNCVs slowed down during BSSO (P = 0.0000 for all parameters). The most obvious changes occurred during surgical procedures on the medial side of the mandibular ramus. There was a clear tendency towards more disturbed IAN conduction with longer duration of these procedures (right side R = -0.529. P = 0.02; left side R = -0.605, P = 0.006). Exposure or manipulation of the IAN usually had no effect on nerve function, but the IAN conduction tended to be more disturbed in cases with nerve laceration. Low corpus height (R = 0.802, P = 0.001) and the location of the mandibular canal near the inferior border of the mandible (R = 0.52, P = 0.02) may increase the risk of IAN injury. There was no correlation between the age of the patients and the electrophysiological grade of nerve damage.  相似文献   
99.
This paper presents a retrospective study carried out on a sample of 100 patients affected by pleomorphic adenoma of the parotid gland and treated at the Department of Maxillofacial Surgery at the University of Rome "La Sapienza" between January 1, 1989 and December 31, 1997. For the diagnosis of this neoformation, cytological tests were performed on material taken from the neoformation using fine needle aspiration and ultrasound scan. In some selected cases, a CT examination of the head and neck with medium contrast or Nuclear Magnetic Resonance (NMR) was carried out. This study sets out to examine the most suitable treatment to be followed for the removal of the pleomorphic adenoma of the parotid gland. In 56 cases the patients underwent a superficial, conservative parotidectomy. Forty one patients had a total parotidectomy with the facial nerve left intact and one patient had a total parotidectomy where the marginal mandibular nerve of the facial nerve was damaged. The remaining two patients involved in the study were suffering from a recurrent pleomorphic adenoma and in these two cases a total parotidectomy was performed where the facial nerve was killed. The removal of the cranial nerve VII in these patients proved necessary because the nerve fibers had adhered to the surrounding scar tissue of the tumor, either after previous surgery or due to repeated chronic phlogosis of the gland.  相似文献   
100.
Meckel's cartilage plays an important role in the topographical organisation and in the differentiation of the facial structure during the embryonal and even much later during the foetal period. Our observations on serial sections carried out in two human foetuses aged 12 and 16 weeks indicate that the two dorsal (tympanic) and ventral (mandibular) branches of Meckel's cartilage are perfectly defined at 16 weeks. In the dorsal branch, the primordia of the incus and of head of the malleus are still composed on non-ossified cartilage. In the ventral branch, it is also possible to describe at 16 weeks three posterior, medial and anterior parts which are composed of cartilage. The initiating role played by the ventral part of Meckel's cartilage on the ossification of the mandible leads during the embryonal period to the formation of the mandibular primary growth center, which is therefore clearly defined in our first stage at 12 weeks. The partial fibrous evolution and the regression of the major part of the ventral branch of Meckel's cartilage only start after 16 weeks of intrauterine life.  相似文献   
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