Intermaxillary fixation is not usually necessary to reduce mandibular fractures.

We undertook a retrospective study of all isolated mandibular fractures which had required active management over a 1-year period at the Maxillofacial Unit at Newcastle General Hospital. Patients with single or multiple fractures of the mandible were included in the study, if there were other simultaneous fractures of the facial skeleton, those patients were excluded. All case notes and radiographs were reviewed by a single operator. A total of 202 cases of fractured mandible were identified of which 115 fulfilled the selection criteria of: isolated fracture, no previous facial fracture, treatment by open reduction and internal fixation using titanium osteosynthesis miniplates, and all case notes and radiographs available to study. Sixty-six patients had their fractures reduced manually to obtain anatomical reduction without the use of peroperative intermaxillary fixation (IMF). Forty-nine were treated conventionally using peroperative IMF. The two groups were broadly similar in severity and type of fracture, and the method of reduction seemed to be decided by the operator according to their preference. IMF was not used routinely postoperatively. Overall there were significantly fewer occlusal discrepancies in the early postoperative period in those patients treated by anatomical reduction (6/66 compared with 16/49, P = 0.002) but there was no difference in the final outcome of the occlusion between the two methods of reduction. Avoidance of the use of peroperative IMF is more economical in time and cost, is safer for the operator, and more comfortable for the patient. As this technique produces comparable results in the long term with fewer early complications, we conclude that IMF is not usually necessary to reduce fractures confined to the mandibular bone.

Cross-matched blood for major head and neck surgery: an analysis of requirements.

We retrospectively analysed our blood ordering practice; the number of units of cross-matched blood requested was compared with the number transfused, in 70 patients undergoing a total of 82 ablative operations for malignant disease. Patients undergoing neck dissection alone, or excision of tumour with free revascularized flap reconstruction without neck dissection, are unlikely to require blood transfusion. Operations that include excision of tumour with primary closure and neck dissection, excision of tumour with pedicled flap reconstruction and excision of tumour with any form of flap reconstruction and neck dissection in continuity, will probably require transfusion. If atypical antibodies are present in the patient's serum on screening, cross-matched blood should always be available preoperatively. Provided that atypical antibodies are not present and that blood is available within 40 minutes from the blood bank, our results show that it is safe to adopt a policy of blood grouping and saving serum, for patients undergoing neck dissection alone, but cross-matching two or more units of blood for patients who are to have more extensive operations.

Needle localisation of the bucco-facial lymph node at surgery.

A simple method of localizing the bucco-facial lymph node at surgery is described, which facilities its excision biopsy.

So you think they know what we do? The public and professional perception of oral and maxillofacial surgery.

In order to assess knowledge about the specialty of oral and maxillofacial surgery amongst the public and both general medical and dental practitioners, a questionnaire was devised. 200 members of the public were selected at random in one district, 50 local dentists and general medical practitioners were selected and all were telephoned to obtain their answers. The results reveal that the majority of the public need more information about the benefits that our specialty can offer them or their patients. Medical practitioners are better informed but lack information about where our major activity lies. Even dental practitioners have not been kept up to date with recent developments in our specialty and may refer to other specialties, patients with conditions which members of our Association routinely manage. If patients are to receive the best treatment available, it is essential that we educate the public (and especially the Purchasers) about our clinical interests and activities.

Familial cold urticaria--a rare cause of lip swelling.

Cold urticaria is an unusual condition characterised by wealing of the skin or mucous membranes following exposure to cold. This report describes a presentation with recurrent lip swelling.

Regulation of product formation during glucose or lactose limitation in nongrowing cells of Streptococcus lactis.

Nongrowing cells of Streptococcus lactis in a pH-stat were dosed with sugar to allow fermentation at the maximum rate or were fed a continuous supply of sugar at rates less than the maximum. Under anaerobic conditions, rapid fermentation of either glucose or lactose was essentially homolactic. However, with strain ML3, limiting the fermentation rate diverted approximately half of the pyruvate to formate, acetate, and ethanol. At limiting glucose fermentation rates, cells contained lower concentrations of lactate dehydrogenase activator (fructose 1,6-diphosphate) and pyruvate formate-lyase inhibitors (triose phosphates). As a result, pyruvate formate-lyase and pyruvate dehydrogenase play a greater role in pyruvate metabolism. In contrast to strain ML3, strain ML8 did not give the same diversion of products under anaerobic conditions, and cells retained higher concentrations of the above effector compounds. Lactose metabolism under aerobic conditions resulted in pyruvate excretion by both S. lactis ML3 and ML8. At 7% of the maximum utilization rate, pyruvate accounted for 69 and 35% of the lactose metabolized by ML3 and ML8, respectively. Acetate was also a major product, especially with ML8. The data suggest that NADH oxidase is involved in coenzyme recycling in the presence of oxygen and that pyruvate formate-lyase is inactivated, but the pyruvate dehydrogenase complex still functions.

Membranes in lupin root nodules. II. Preparation and properties of peribacteroid membranes and bacteroid envelope inner membranes from developing lupin nodules.

Peribacteroid membranes and bacteroid envelope inner membranes have been isolated from developing lupin nodules. Isolation of the peribacteroid membranes was achieved by first preparing membrane-enclosed bacteroids free from other plant organelles or membranes. The peribacteroid membranes were then released by osmotic shock and purified by centrifugation to equilibrium on sucrose gradients. The bacteroids were broken in a pressure cell and the bacteroid envelope inner membranes were isolated using sucrose gradient fractionation of the bacteroid total envelope preparation. The density of the peribacteroid membranes decreased during the period of development of N2-fixation in lupin nodules from 1.148 g/ml for nodules from 12-day plants to 1.137 g/ml for nodules from 18-day plants. The density of the bacteroid envelope inner membranes from nodules from 18-day plants was 1-153 g/ml. The identity and homogeneity of the isolated membranes was established, by comparison with membranes in intact nodules, using phosphotungstic acid and silver staining of thin sections and particle densitites on faces of freeze-fracture replicas of the membranes. Analyses for NADH oxidase and succinate dehydrogenase, spectral analyses and gel-electrophoretic analysis of proteins were also used to characterize the membrane and soluble protein fractions from the nodules. The ratio of lipid to protein was 6.1 for the peribacteroid membranes and 2.5 for the bacteroid envelope inner membranes. Leghaemoglobin was localized in the plant cytoplasm in lupin nodules and not in the peribacteroid space.