Assessing competency in dentoalveolar surgery: a 3-year study of cumulative experience in the undergraduate curriculum

AIM

To assess and observe the development of competence in oral surgical skills during a 3-year undergraduate programme.

METHOD

Over a 3-year period 75 students were followed through from the beginning of their clinical course to their Bachelor of Dental Surgery graduation and their surgical experience monitored by the use of logbooks. Their development of competence was assessed objectively through structured assessments and subjectively by a single tutor responsible for each year. Assessments were made of their ability in exodontia, pre-surgical assessment and the surgical extraction of teeth/roots.

RESULTS

Seventy-three students completed the course (97%). Successful completion rates for the objective testing were 100% for both exodontia and pre-surgical assessment. The surgical assessment, (surgical extraction of a tooth or root) had a successful completion rate of only 23% and the caseload for students was low with a mean of four teeth removed surgically upon graduation. Relationships were examined between total numbers of teeth extracted, total number of minor oral surgical procedures completed and the successful completion of the surgical competence assessment, but no significant relationships were found.

CONCLUSIONS

This study demonstrates that it is possible to achieve objectively measurable levels of competence in undergraduates undertaking oral surgery procedures. It is however, a labour and time intensive process and appropriate clinical and teaching resources are required. National co-operation towards agreed standardised competencies should be encouraged to allow data to be pooled and more powerful analyses to occur.

Serum antibody responses of cattle to iron-regulated outer membrane proteins of Pasteurella haemolytica A1

Serum antibody responses to the 70, 77, and 100 kDa iron-regulated outer membrane proteins (IROMPs) of Pasteurella haemolytica A1 were studied in cattle vaccinated with outer membrane protein (OMP) enriched outer membrane fraction, IROMP-enriched outer membrane fraction or live P. haemolytica. Vaccination with an IROMP-enriched outer membrane fraction stimulated antibodies to the 70 kDa IROMP, whereas vaccination with live P. haemolytica stimulated antibodies to the 70 and 77 kDa IROMPs. In a second experiment, sera were used from cattle vaccinated with live or killed P. haemolytica and subsequently challenged. Significant antibody responses to OMP- and IROMP-enriched outer membrane fractions were detected by an enzyme-linked immunosorbent assay (ELISA) for cattle vaccinated with bacterins or live P. haemolytica. Regression analysis indicated significant correlations between high antibody responses to the OMP- or IROMP-enriched fraction and resistance to challenge. Antibody responses to the 70 and 77 kDa IROMPs were significantly greater for the live P. haemolytica vaccinates than for PBS control vaccinates. There was no significant correlation between antibody responses to individual IROMPs and resistance or susceptibility to challenge. These data suggest that antibodies to IROMPs alone are probably not responsible for protective immunity against pneumonic pasteurellosis. Antibodies to IROMPs, however, in conjunction with antibodies to other surface antigens probably enhance immunity to P. haemolytica challenge.

Saline-extracted antigens of Pasteurella haemolytica: separation by chromatofocusing, preliminary characterization, and evaluation of immunogenicity

Saline extracts of logarithmic-phase Pasteurella haemolytica, serotype 1, were separated by chromatofocusing. The resulting fractions were analyzed by immunodiffusion and an enzyme-linked immunosorbant assay, and six antigen groups (AG's) were identified. AG 1 did not bind to the column, AG's 2, 3 and 4 were eluted with a decreasing pH gradient, and AG's 5 and 6 were eluted with an increasing NaC1 gradient. Fractions containing each AG were pooled and further purified by gel filtration. The AG's were subsequently characterized as to protein, carbohydrate and 2-keto-3-deoxyoctanate (KDO) content. AG's 1, 5, and 6 had higher carbohydrate contents than AG's 2, 3 and 4. Only AG 5 contained detectable levels of KDO. The AG's were also analyzed by SDS-PAGE and immunoblotting. Each AG produced a characteristic pattern of proteins and antigens, although two antigenic proteins were common to all AG's. AG 1 contained the greatest number of antigenic proteins. Immunization of mice with each AG in Freund's incomplete adjuvant resulted in a strong antibody response to the homologous AG for four of the six AG's. Limited protection against a P. haemolytica challenge was observed in mice that were immunized with AG 2 or 4.

Inhaled beclomethasone dipropionate suppresses the hypothalamo-pituitary-adrenal axis in a dose dependent manner

OBJECTIVE

Little is known about the dose-response relationship of potential, unwanted, effects of inhaled beclomethasone (BDP) on the hypothalamo-pituitary-adrenal (HPA) axis, particularly in nonspecialist clinic settings. The purpose of our study was to investigate the dose-response relationship of inhaled BDP on the HPA axis in a general practice patient population. We also explored the optimal testing strategy in this population and correlated effects of inhaled BDP on the HPA axis with other systemic corticosteroid side effects.

PATIENTS AND DESIGN

Controlled observational study employing 21 patients on inhaled BDP recruited from general practice, with minimal past and no present exposure to other corticosteroids, and 21 age and gender-matched controls.

MEASUREMENTS

Twenty-four-hour urinary free cortisol excretion (UFC), serum cortisol before and 30 minutes after injection of 1 microgram and 250 micrograms of tetracosactrin, serum IGF-I and serum osteocalcin were measured. BDP use was estimated by inhaler weighing and prescription count.

RESULTS

In subjects on inhaled BDP, 24-hour UFC (P < 0.008), serum cortisol 30 minutes after 250 micrograms tetracosactrin (P < 0.05) and the serum cortisol rise after 250 micrograms tetracosactrin (P < 0.04) were significantly lower when compared with controls. Measurements of HPA function correlated inversely with BDP dose estimated by inhaler weighing (all P < 0.03). Serum IGF-I and osteocalcin levels did not differ.

CONCLUSIONS

We have demonstrated hypothalamo-pituitary-adrenal axis suppression in nonspecialist-clinic asthma patients on moderate to large doses of inhaled beclomethasone dipropionate. When accurate measurements of inhaled steroid dose are used, there is an exponential relationship between dose and hypothalamo-pituitary-adrenal axis suppression. There appears to be no 'safe' threshold, and around 15% of patients may have clinically significant suppression. However, the significance of hypothalamo-pituitary-adrenal axis suppression as a marker for concomitant corticosteroid effects on other organ systems remains uncertain.

Postoperative radiographs after open reduction and internal fixation of the mandible: Are they useful?

Mandibular fractures are common in oral and maxillofacial departments in the UK. The aim of this study was to find out the national practice in preoperative and postoperative radiographic investigations for fractured mandibles and to audit their diagnostic capacity, including specificity and sensitivity to short-term complications. The audit took place over a 4-month period and involved 100 patients across the Northern region. Ninety percent of patients were reviewed up to discharge and five of these patients developed a short-term postoperative complication. The postoperative radiograph was diagnostic in only one of the five cases. Overall, postoperative radiographs had a sensitivity of 20% and a specificity of 5% in their ability to predict short-term postoperative complications.

Hepatotoxicological evaluation of dantrolene sodium

The clinical use of dantrolene has been associated with hepatotoxicity, thus the toxicity of dantrolene in Swiss-Webster mice was characterized. Animals were treated orally (po) with single or multiple doses of up to 400 mg/kg of D without any increases in SGPT or alterations in hepato-cellular architecture. To possibly enhance the hepatotoxicity of dantrolene, its biotransformation was altered by inhibiting acetylation, depleting glutathione, inducing biotransformation, and promoting reductive metabolism. None of the metabolic alterations elicited any toxicity of dantrolene. Hepatic microsomal incubations were used to detect the possible bioactivation and covalent binding of 14C-dantrolene. Analysis for covalent adducts found only 20-30 pmol bound/mg microsomal protein. Thus the suspected hepatotoxicity of dantrolene does not appear to be linked to its biotransformation or bioactivation. Additional studies will be necessary to clarify if other parameters are necessary for dantrolene to be a hepatotoxin.

Monoclonal antibodies to Pasteurella haemolytica serotype 1 lipopolysaccharide: demonstration of antigenic similarities among several serotypes

Murine monoclonal antibodies (MAbs) were produced which were specific for Pasteurella haemolytica serotype 1 lipopolysaccharide (LPS). The MAbs also reacted with LPS present in a partially purified antigen derived from a saline extract of the organism. The epitope to which the MAbs were directed was a carbohydrate which was sensitive to oxidation with periodate, had a molecular weight between 14,000 and 25,000 as determined by immunoblotting, and was present in a crude O-antigen preparation of P. haemolytica LPS. The MAbs did not react with purified capsular polysaccharide from P. haemolytica serotype 1. In an enzyme-linked immunosorbent assay, reaction of the MAbs with LPS obtained from 14 gram-negative bacteria failed to detect any cross-reactivity with P. haemolytica LPS. However, the MAbs detected antigenic similarities among P. haemolytica serotypes 1, 5, 6, 7, 8, and 12 and, to a lesser extent, 4 and 14. These studies indicate that the LPS-O-antigens from several P. haemolytica serotypes have similar epitopes and may be partially responsible for shared antigenicity among serotypes.

Attitudes regarding specialist referrals in periodontics

OBJECTIVE

To examine the attitudes of dental practitioners towards specialist periodontal referral in the North East of England.

SUBJECTS AND METHODS

Semi-structured interviews were conducted with a purposive sample of 10 practitioners. Interviews continued until data saturation occurred. The data were organised using a framework and analysed by two researchers working independently.

RESULTS

Perceptions of periodontal disease and treatment appear to be heavily influenced by the NHS remuneration system. Treatment in general practice was limited to simple scaling and there was an apparent reluctance to treat advanced periodontitis. Such cases were commonly referred to specialists, confirming the demand for a referral service in periodontics. The perceived potential for medico-legal consequences was a strong driver of referrals. Distance to the referral centre and the perceived costs of treatment were significant barriers to referral. Dentists valued the specialist's personal reputation and clinical skills more highly than academic status. Deficiencies in communication between primary and secondary care were highlighted.

CONCLUSIONS

Increased resources are required to manage periodontal diseases within the NHS. There is a need for a periodontal referral service in the North East of England to improve accessibility to specialist care. This would appear to be most appropriately delivered by increased numbers of specialist practitioners.

Pasteurella haemolytica: purification of saline-extractable proteins by isoelectrofocusing

A procedure was developed for separating antigens associated with a saline extract of Pasteurella haemolytica serotype 1. Seven antigens were identified by immunoelectrophoresis to be associated with the extract. The extract was subjected to preparative isoelectrofocusing in a pH range of 3-10. The majority of extracted proteins were found to have pI's of 4-6, whereas the carbohydrate antigen(s) were distributed over a pI range of 3.0-8.0. The fractions that were of interest were pooled and refocused in a narrower pH range to improve resolution of the protein antigens. Specific antigens from defined pH ranges were pooled to form 6 antigen groups. These antigen groups were examined further by immunoelectrophoresis, analytical isoelectrofocusing, and sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The molecular weights of the proteins found in the capsular extracts ranged from 33 k to greater than 80 k. Injection of mice with capsular extract or antigen Groups 1-6 in Freund's incomplete adjuvant resulted in a serum antibody response to the various antigens as detected by an enzyme-linked immunosorbent assay. Significant protection (P less than 0.05) against challenge with virulent P. haemolytica was seen in mice injected with antigen Groups 2 and 4. Six calves were immunized with saline extract. These calves had greater resistance to experimental pneumonic pasteurellosis than did 6 non-vaccinated calves. A serum antibody response to the crude extract and to each antigen group was detected in vaccinated calves by an enzyme-linked immunosorbant assay.

Evaluation of a virtual anatomy course for clinical undergraduates

AIM

To implement and evaluate a series of interactive clinically applied anatomy tutorials for final year dental undergraduate students.

METHODS

A 6-week voluntary virtual program of tutorials for final year dental undergraduates, with pre- and post-tutorial testing, was evaluated using a priority sequence model (QualQuan). A purposive sample (n = 15) was taken of the year group (n = 69) and the initial qualitative phase in depth interviews were carried out until data saturation (n = 13). The emergent recurrent themes from the qualitative data were then phrased into a variety of non-leading questions. These questions were issued in the form of an anonymous electronic questionnaire to the whole student body.

RESULTS

There was a good uptake of the tutorials with 84% of the students accessing at least one tutorial before sitting their final examinations. A response rate of 70% was achieved for the quantitative evaluative questionnaire phase of the study. Overall perceptions of the course were favourable although a number of modifications were suggested. These included a more concise presentation of the mainstream tutorial text with hyper links to more detailed content. Students also indicated a desire for more line diagrams. These changes, it was suggested, would help with the on-line readability of the tutorials. The primary focus for the students' learning appeared to be provided by the pre- and post-tutorial tests even though explicit learning outcomes were provided for each tutorial.

CONCLUSION

This study demonstrates that a well-designed virtual course can help to vertically integrate, and make clinically relevant, one of the basic sciences underpinning dental surgery. It has shown that formative assessment acts as a powerful tool to focus student attention and direct student learning. This leads to the conclusion that formative assessments have to be designed with as much care and attention as summative assessments.

Aortic chondroid neoplasia in two Labrador Retriever dogs

In the same week, two Labrador Retriever dogs presented to The Ohio State University Veterinary Medical Center for cardiac evaluation. The presenting signs in both dogs included: weight loss, weakness, lethargy, and decreased femoral pulses. The first dog presented in cardiogenic shock and biventricular congestive heart failure, which initially responded to treatment; however, the dog was euthanized due to deteriorating clinical condition. In contrast, the second dog had a milder clinical course without signs of congestive heart failure, and remained stable over the 2-month period of clinical evaluation prior to euthanasia. Echocardiographic evaluation revealed a dilated cardiomyopathy phenotype in the first dog, while a space-occupying intraluminal mass originating at the aortic valve with preserved left ventricular systolic function was observed in the second dog. At autopsy, each dog had a large obstructive luminal mass affecting the ascending aorta and arch. Histopathology revealed that the mass in the first dog was consistent with a benign chondroma, while in the second dog the morphologic characteristics, mitotic activity, and infiltrative growth justified a diagnosis of chondrosarcoma. This report presents the contrasting clinical disease progression and findings in two dogs with aortic neoplasia, with a proposed pathogenesis of cardiac failure secondary to aortic neoplasia.

A national follow-up survey of UK graduates opinion of undergraduate oral surgery teaching

INTRODUCTION

A national follow-up survey was undertaken to determine whether dental graduates from 2009 perceived that their undergraduate oral surgery education had equipped them for general dental practice 4 years after graduating.

MATERIALS AND METHODS

Graduates from the same 13 United Kingdom dental schools who had taken part in the original survey were invited to take part in this follow-up online survey. Their contact details were identified via the general dental council register, social media and alumni groups.

RESULTS

In total, 161 responded (2009b) which represents 16% of the graduates of the original survey in 2009a. A similar percentage of these respondents perceived that the teaching in oral surgery had given them sufficient knowledge to undertake independent practice (83% and 79% in 2009a and 2009b, respectively). Most respondents (99% in both years) reported confidence in undertaking simple forceps exodontia. Confidence in surgical exodontia was poor in both surveys, but one area that appeared improved in the follow-up related to the sectioning of teeth (84% in 2009b compared with 49% in 2009a). Areas of weakness identified in 2009 were reported to be improved in the follow-up.

CONCLUSION

This follow-up survey supports the findings of the original survey. Future longitudinal studies would allow institutions to identify possible weaknesses in their curriculum and to track the career development of their graduates and facilitate robust data collection.

Comparison of the antigens associated with saline solution, potassium thiocyanate, and sodium salicylate extracts of Pasteurella haemolytica serotype 1

Pasteurella haemolytica antigenic extracts were made, using saline solution, potassium thiocyanate (KSCN), and sodium salicylate (SS) extraction procedures. Of the 3 techniques, saline solution extraction resulted in the lowest protein concentration and lowest ribonucleic acid-to-protein ratio. The extracts varied in protein:carbohydrate ratios, with the KSCN extract being highest and the saline solution extract the lowest. Each extract contained lipopolysaccharide, as determined by detectable quantities of 2-keto, 3-deoxyoctonate. The saline solution extract contained the fewest protein bands by sodium dodecyl sulfate-polyacrylamide-gel electrophoresis, but contained the highest molecular weight proteins. All 3 extracts were reasonably similar antigenically, as detected by immunoblotting. Many of the protein bands present in the KSCN or SS extracts did not seem to be antigenic. Each extract was subjected to chromatofocusing, and the greatest antigenic peak, for each extract, failed to bind to the exchanger. These highly antigenic peaks, designated as saline solution, KSCN, or SS antigens, were similarly high in carbohydrate content, had similar antigenic-profiles, and contained high molecular weight (greater than 200,000) antigenic material, most likely carbohydrate in nature, as detected by immunoblotting. Inoculation of mice with 1 of the 3 extracts or the saline solution antigen resulted in marked antibody responses; however, protection against intraperitoneal challenge exposure to P haemolytica was minimal.

Use of diagnostic imaging services in the Central Region by general practitioners

AIM

To record general practitioners use of diagnostic imaging facilities in areas with different levels of access.

METHOD

A random sample of general practitioners from three different areas kept a prospective record for one month of all patients referred to diagnostic imaging facilities, the outcomes of these investigations and the total number of patients seen.

RESULTS

Referrals for diagnostic imaging services were significantly different between the localities (p = 0.014). The area with the least restrictions on access and the highest referral rate showed the greatest variation between doctors. There was a significant difference (p = 0.047) between the localities for patients who could not be referred because of restricted access and the cost of the services. The majority (68%) of patients who were unable to access these services were referred to the hospital for admission, for an outpatient appointment or to the accident and emergency department. There was little difference between the localities in either the presence or absence of pathology, or in the proportion of patients where the diagnosis was changed as a result of the diagnostic imaging investigation.

CONCLUSION

Improved access to diagnostic imaging services for patients of general practitioners would result in better patient management and prevent unnecessary hospital referrals.

Evaluation of a behavioral audiometry simulator for teaching visual reinforcement audiometry

Eight audiology students with little or no visual reinforcement audiometry (VRA) experience each performed a VRA test on an infant. Four of the students received approximately 5 hours of behavioral audiometry simulator (BAS) training, and 1 week later, after the first VRA test, all eight students tested a second infant. Student performance was rated by three audiologists who were experienced in performing VRA with infants. The performance of the group that received BAS training improved significantly while the performance of the control group did not. Among the students who received BAS training, those who improved the most during stimulated testing also showed the greatest improvement in VRA with real infants.

Comparison of antigens of Pasteurella haemolytica serotype 1 grown in vitro and in vivo

To determine whether antigenic differences exist in Pasteurella haemolytica serotype 1 grown in different culture conditions, the bacteria was grown on solid enriched medium, in broth culture, and in tissue chambers subcutaneously implanted in the flanks of calves. The organisms obtained by each culture method were comparable with respect to encapsulation and lipopolysaccharide content. In the bacteria grown in vivo, several unique high molecular-mass (greater than 150 kDa) protein antigens were found by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and protein immunoblotting. Bacteria grown in vitro had higher concentrations of a 49- and a 26-kDa protein than the organisms grown in vivo. The concentration of several major proteins (30, 42, 55, 71, and 100 kDa) were similar among the organisms grown by the three cultural conditions. Although the high molecular-mass antigens were unique for the chamber-grown bacteria, they were recognized by serum from a calf that had been vaccinated with formalin-killed, solid medium-grown P haemolytica and were resistant to challenge exposure with the live organism. This recognition of antigens by serum from the P haemolytica-resistant calf that had been vaccinated with solid-medium-grown bacterium, indicates that the high molecular-mass antigens from chamber-grown P haemolytica may be precursors of or share antigenic determinants with other P haemolytica proteins and may not be important for consideration in vaccine formulation.

A qualitative study of general practitioner access to diagnostic imaging services in the Central Region

AIMS

To determine general practitioners' views about access to diagnostic imaging services in the Central Region, particularly for low-income patients, and the perceived impact of limited access on patient outcomes.

METHOD

A key general practitioner in each of 21 main geographical localities facilitated a discussion with a group of general practitioners using a pretested questionnaire. Each group tried to reach a consensus view and these responses were analysed to determine the common themes and ideas.

RESULTS

General practitioners identified difficulties and barriers to access for all common diagnostic imaging procedures throughout the Central Region. Cost was the main barrier to access. Limited access resulted in increased risk for patients, unnecessary use of outpatient facilities and wasted time for general practitioners. Up to 40% of patients with restricted access to diagnostic imaging services were referred to outpatient departments and up to 20% went without the service.

CONCLUSION

Many general practitioners in the Central Region do not have direct access to diagnostic imaging services except for patients who can afford private services. This is thought to generate significant additional costs and risks for patients. Improved access to these services would reduce hospital outpatient waiting times and provide a better service for patients.

Sequential development of antigens and toxins of Pasteurella haemolytica serotype 1 grown in cell culture medium

Pasteurella haemolytica was grown in nonsupplemented cell culture medium, or in medium supplemented with bovine serum albumin (BSA) for 24 hours. The production of leukotoxin (LKT) and endotoxin was sequentially evaluated, as were bacterial antigens associated with bacterial cell lysates and culture supernates. Supplementation of medium with BSA had no effect on bacterial growth curves; however, LKT activity was detected earlier and was greater in culture supernates from BSA-supplemented media than from nonsupplemented medium. Leukotoxin antigen (105 kDa) was detected in culture supernates, using a monoclonal antibody, immunoblot analysis, and densitometry. The relative concentrations of LKT antigen were proportional to LKT activity. Endotoxin activity was initially lowest in the culture supernates from nonsupplemented medium, but increased during the incubation period, whereas endotoxin activity in BSA-supplemented culture supernates decreased with time in culture. In culture supernates from nonsupplemented medium, the number of antigenic bands identified by immunoblot analysis with hyperimmune anti-P haemolytica and densitometry was greater than in culture supernates from supplemented media. In bacterial lysates, a 95-kDa antigen was the major antigen detected, using the anti-LKT monoclonal antibody. The concentration of that antigen varied among lysates from nonsupplemented medium and BSA-supplemented media. Using hyperimmune anti-P haemolytica serum, minor differences were seen in the relative quantities of lysate-associated antigens dependent on time in culture and medium used. Among the major antigens seen, differences were most apparent for 150-, 100-, and 87-kDa antigens, whereas differences were not obvious for 42- 40-, and 30-kDa antigens.(ABSTRACT TRUNCATED AT 250 WORDS)