Retrospective Study on Efficacy of Intermaxillary Fixation Screws

Background

We evaluated the efficacy of intermaxillary fixation (IMF) screws in the treatment of mandibular fractures.

Methods

Two hundred patients with mandibular fractures, treated by IMF using these screws, were evaluated by pre and postoperative panoramic radiographs. Clinical testing was carried out for vitality and abnormal mobility of teeth adjacent to the site of screw insertions. Other factors such as possible iatrogenic dental injuries, loss, breakage or screw cover by oral mucosa and postoperative occlusion were also studied.

Result

The most important complication noticed was iatrogenic damage to dental roots.

Conclusion

Use of intraoral cortical bone screws for IMF is a valid alternative to arch bars in the treatment of mandibular fractures. Iatrogenic injury to dental roots is the commonest problem which can be minimized by an experienced surgeon.Key Words: Intermaxillary fixation, Bone screws, Mandibular fractures, Iatrogenic injury     

Progressive and regressive changes in the nucleus pulposus. Part I. The neonate

Magnetic resonance (MR) imaging, correlated with anatomic sections, was used to characterize the progressive and regressive changes in the nucleus pulposus in neonates. The spines of five fetuses and five full-term infants between 16 and 40 weeks old were studied. In anatomic sections, the nucleus pulposus was sharply demarcated from the anulus fibrosus, Sharpey fibers were conspicuous, and a plate of primitive notochord was evident in the equator of the disk. On long repetition time (TR)/long echo time (TE) or long TR/short TE MR images, Sharpey fibers (low signal intensity) and notochord (low signal intensity) could be differentiated from the high-signal-intensity nucleus pulposus and anulus fibrosus. The major differences between the fetal and infant spines were the amount of notochord in the disk and ossification in the vertebral body.     

INITIAL EXPERIENCE WITH SHOCK WAVE LITHOTRIPSY AT ARMY HOSPITAL (R & R) DELHI CANTT

Army Hospital (R & R) has acquired an Electrohydraulic Lithotripter (DIREX NOVA), the first of its kind in the Armed Forces for the treatment of stone diseases. The first 200 patients who underwent Extracorporeal Shock Wave Lithotripsy (ESWL) have been analysed in this study. This being a pilot study would serve as a beginning of an ongoing experience with this non-invasive procedure and its benefits for the stone population in the Armed Forces.KEY WORDS: ESWL, Lithotripsy     

TRANSFUSION REACTIONS: AFMC EXPERIENCE

Transfusions of blood and its components are useful and lifesaving. Adverse effects occur during or after transfusion, called hazards or complications of blood transfusion. Complications/hazards of various types which occurred in the patients following transfusion of blood/blood components in Armed Forces Hospitals of Pune-Kirkee complex were analysed with relevant investigations. Out of a total number of 13,039 transfusions of blood and blood components from 01 June 1995 to 31 July 1997, there were 104 (0.8%) adverse reactions. Non haemolytic febrile transfusion reaction was the commonest seen in 73 (70.2%) transfusions, followed by allergic reactions in 19 (18.3%) cases. Nonspecific reactions were seen in 11 (10.6%). One haemolytic transfusion reaction occurred due to wrong labelling of blood sample received from the ward for compatibility testing. There were no fatalities.KEY WORDS: Blood transfusion, Complication, Febrile reaction     

EARLY DIAGNOSIS IN POST RENAL TRANSPLANT OPPORTUNISTIC INFECTIONS: A FRESH LOOK

A total of 86 renal transplant patients who were transplanted with live related donor (LRD) and live unrelated donor (LURD) kidneys were studied for opportunistic infections. Immune diagnosis of Toxoplasma, Cytomegalovirus (CMV), Herpes-simplex virus type II (HSV-2), Aspergillosis and Tuberculosis was carried out in these patients along with sputum examination, CSF studies and biopsy of lymphnode and other tissues in few cases. A high degree of Toxoplasma, CMV & HSV-2 positivity was seen in transplanted patients. However sensitivity of serological diagnosis of tuberculos was found to be low with standard criteria, which increased significantly when modified criteria were used. It is concluded that regular immunological monitoring should be carried out in transplanted patients so as to reach an early diagnosis and management of opportunistic infections.KEY WORDS: Immune diagnosis, Opportunistic infections, Transplantation     

O16 Organoleptic assessment of pure odour compounds representative of the metabolic end‐products of oral microbes

We have measured various production rates of volatile compounds in tongue scrape cell suspensions, oral biofilm models and the oral cavity in situ and wish to relate these to equivalent levels of oral malodour as assessed by the human nose. Objectives To assess the relationship between measured concentrations of pure odourants and resultant organoleptic scores (using a defined 0–5 score). Methods Seven odour judges, all with experience of organoleptic assessment, were used in this study for all experiments carried out at a single site (UWE, Bristol). A wide range of pure odourants were prepared at a range of concentrations (from a stock of 0.1 M) and were dispensed as 12 ml volumes into ‘universal’ bottles (24 ml capacity) leaving a headspace of 12 ml. The bottles were secured with rubber‐lined metal caps, labelled with a randomized code and were presented to the odour judges for assessment using the Rosenberg 0–5 scale. The volatile sulphur compounds (H₂S and CH₃SH) were presented as gases with dilutions being prepared through a dynamic gas flow rig (using oxygen free nitrogen as the diluent) and presented to the odour judges at a flow rate of 200 ml min^?1. Group means of determinations for each odourant were plotted against log10 of the concentration. Linear regression analysis was used to measure the gradient, 95% CI, and the scatter of the points around the gradient (R² value). Results Organoleptic scores were proportional to the log10 concentration of odourant. Detection thresholds (expressed as mol dm^‐3) were skatole (7.2 × 10^?13) < methyl mercaptan (1.0 × 10^?11) < trimethylamine (1.8 × 10^?11) < butyrate (2.3 × 10^?10) < hydrogen sulphide (6.4 × 10^?10) < putrescine (9.1 × 10^?10) < dimethyldisulphide (5.9 × 10^?8). Hydrogen sulphide showed highest olfactory power whilst putrescine was the lowest. Conclusions The olfactory response is exponential in nature. For any single compound, its contribution to malodour depends on: odour (olfactory) power, threshold (of detection) and volatility in addition to the concentration. It is now possible to relate production rates of VC's in models to typical levels of oral malodour perceived by the human nose.     

The inability of Streptococcus mutans and Lactobacillus acidophilus to form a biofilm in vitro on dentine pretreated with ozone

Background: The use of ozone therapy in the treatment of dental caries is equivocal. The aim of this study was to use an in vitro model to determine the effects of prior ozone application to dentine on biofilm formation and to measure any associated reduction in bacteria viability. Methods: Twenty dentine discs were bonded to the bases of 5 mL polycarbonate screw top vials. Ten dentine discs were infused with ozone for 40 seconds, 10 samples remained untreated as a control. The vials were filled with nutrient medium, sterilized and placed into the outflow from a continuous chemostat culture of Streptococcus mutans and Lactobacillus acidophilus for four weeks. At the conclusion of the experiment bacterial growth was monitored by taking optical density readings of the growth medium in each vial and the outer surface of the dentine specimens were examined by scanning electron microscopy as shown by SEM analysis. Results: Ozone infusion prevented biofilm formation on all the treated samples while there was substantial biofilm present on the control specimens. While the average optical density of the control specimens was almost twice that of the ozone infused dentine (0.710 for the control with a SD of 0.288 and 0.446 for the ozonated samples with a SD of 0.371), the results were not significant (p > 0.05). Conclusions: This preliminary study has shown that the infusion of ozone into non‐carious dentine prevented biofilm formation in vitro from S. mutans and L. acidophilus over a four‐week period. The possibility exists that ozone treatment may alter the surface wettability of dentine through reaction with organic constituents.