Biomedical subjects

S McHugh

Publications and source records attributed to S McHugh.

At least 19 recordsLinked to original sources

PubMed2006

The behaviour, social status and number of teeth extracted in children under general anaesthesia: a referral centre revisited.

OBJECTIVE: To report on the changing profile of children attending for Dental General Anaesthetic extractions (DGA) at the same centre in 1998 and again in 2004 compared to 1991. DESIGN: Prospective clinical. SETTING: Glasgow Dental Hospital DGA service during August 1999 and August/September 2004. SUBJECTS AND METHOD: Children presenting for DGA extractions. Data recorded: age, gender, number of teeth extracted and level of behaviour using the Frankl scale. RESULTS: In 1999: 190 children (97 boys) mean age five years. In 2004: 106 children (55 boys) mean age five years. There was a significant increase in the mean number of teeth extracted (p < 0.001), 4.2 (1-16) and 7.8 (1-17) in 1999 and 2004 respectively, compared to 3.7 in 1991. Twenty-six per cent of children had between six and 16 teeth extracted in 1999 compared to 74% in 2004. Significantly fewer children demonstrated "definitely positive" behaviour compared to 1991. Children were in the poorest socioeconomic groups, reflecting the geographic area. CONCLUSION: Over half of the children were aged five years and under. Fewer highly co-operative children were treated. More teeth were extracted per child, suggesting that there should be greater opportunities to carry out restorations, not just extractions under general anaesthesia.

Age Factors↗

PubMed2006

No to chlorhexidine.

Explore the source record for details and available documents.

Anti-Infective Agents, Local↗

PubMed2006

Magnitude and reproducibility of forces generated by clinicians during laceback placement.

OBJECTIVE: To determine the magnitude and reproducibility of forces generated by clinicians during laceback placement using a force-measuring typodont. SETTING: An in vitro investigation. MATERIALS AND METHODS: An in vitro typodont model was developed, which incorporated strain gauges attached to a personal computer to allow measurement of the force generated on application of lacebacks. Ten operators were instructed to place lacebacks five times, on two separate occasions (T1 and T2). Inter-operator and intra-operator forces produced at T1 and T2 were compared. MAIN OUTCOME MEASURES: Forces generated by laceback placement. RESULTS: The forces generated by clinicians ranged from 0 to 11.1 N. There were significant differences in the mean forces generated by the different operators (P < 0.001), with differences between time points not being consistent across all operators (P < 0.001). Some operators were more consistent than others in the forces generated. CONCLUSION: In vitro, there was a large inter-operator variation in the forces produced during laceback placement. With the in vitro model used in this study, few operators applied similar forces when placing lacebacks on two separate occasions.

Analysis of Variance↗

PubMed2005

A study of visual and blood contamination on reprocessed endodontic files from general dental practice.

OBJECTIVE: This study examined methods used for reprocessing endodontic instruments in general dental practice and determined the degree of residual visual contamination and blood contamination on 250 reprocessed files collected from 25 general dental practices. MATERIALS AND METHODS: A questionnaire was administered to 25 general dental practitioners to obtain information on the re-processing of used endodontic files. Ten files which had been used and reprocessed were also collected from each practice. These were examined visually under a dissecting light microscope for residual contamination and then tested for blood deposits using the Kastle-Meyer test. RESULTS: Nineteen of the 25 practices used stainless steel hand files. No practitioners used endodontic files as single use devices. Ninety-two per cent of the practitioners discarded and replaced files when they were bent or damaged. Several decontamination methods were reported. The two combinations employed most frequently were manual cleaning and autoclaving or manual cleaning, followed by ultrasonic cleaning and autoclaving. Of the 250 files, 75% showed some degree of visual contamination and seven percent tested positive for residual blood. Blood contaminated files were significantly more heavily contaminated when examined visually. Large variations were found in residual contamination of files collected from practices using the same methods of decontamination. CONCLUSIONS: While all practitioners re-used endodontic files, the variations in decontamination methods reported indicate a lack of clarity on best practice. This study demonstrates that endodontic files are not reliably decontaminated by methods currently employed in dental practice.

Blood↗

PubMed2005

Propagation of avalanches in Mn12-acetate: magnetic deflagration.

Local time-resolved measurements of fast reversal of the magnetization of single crystals of Mn12-acetate indicate that the magnetization avalanche spreads as a narrow interface that propagates through the crystal at a constant velocity that is roughly 2 orders of magnitude smaller than the speed of sound. We argue that this phenomenon is closely analogous to the propagation of a flame front (deflagration) through a flammable chemical substance.

Journal Article↗

PubMed2005

UK dentists' attitudes and behaviour towards Atraumatic Restorative Treatment for primary teeth.

BACKGROUND: Atraumatic Restorative Treatment (ART) was introduced a decade ago as a minimal intervention treatment for caries in unindustrialised countries, but UK general dental practitioners (GDPs) may also be using this technique. OBJECTIVE: This study aimed to determine the materials and techniques used by a group of UK GDPs to treat caries in primary teeth. METHOD: A questionnaire, designed to determine GDPs' use of materials and techniques in the restoration of caries in primary teeth, was distributed to 600 GDPs in Scotland and England, with an explanatory letter and reply-paid envelope. The questionnaire included colour illustrations of two carious cavities in primary molar teeth and a request that respondents draw the cavity outline that they would use on the illustrations. The cavity outlines were assessed independently by two examiners. All other data were collated and analysed. RESULTS: 390 usable replies were received, a response rate of 65%. Of the respondents, 99% treated child patients and 42% of respondents were aware of ART. For treatment of a small Class II cavity, 37% drew a cavity outline without extension beyond removal of caries and a majority suggested use of an adhesive material (51% glass ionomer, 13% compomer). For cavity preparation, 47% of respondents used a drill, 10% an excavator and 41% used both. For treatment of a large occluso-lingual cavity, again most used an adhesive technique (44% glass ionomer, 12% compomer) for its restoration, while 50% used a drill, 7% an excavator and 42% used both for cavity preparation. CONCLUSION: Most respondents used adhesive materials for restoration of caries in primary molars, but, despite 42% of respondents stating that they were aware of the treatment, "true" ART was adopted by fewer than 10% of respondents.

Attitude of Health Personnel↗

PubMed2005

Residual protein levels on reprocessed dental instruments.

Reduction of the initial bioburden on instruments, prior to sterilization, is believed to reduce transmission risks of iatrogenic Creutzfeldt-Jakob disease. Endodontic files are used in the preparation of root canals and are likely to have close contact and become contaminated with neural material from branches of the maxillary and mandibular cranial nerves. This study examined methods used by 22 dental practices to clean endodontic files, and scored visible debris and residual protein levels adhering to 220 dental endodontic files that had been used, cleaned, autoclaved and were deemed ready for re-use. Visible debris was scored after examination under a dissecting light microscope. Residual protein was quantified using a fluorescent assay based on reaction of proteins with o-phthaldialdehyde/N-acetyl cysteine. There was wide variation in the methods used by practices to clean endodontic files. The cleaning process varied from a wipe with an alcohol-impregnated cloth to hand scrubbing and/or use of an ultrasonic bath. Surface debris was visually detected on 98% of files. Residual protein was detected on all the files examined (median amount: 5.4 microg; range: 0.5-63.2 microg). These results demonstrate that the cleaning of some instruments reprocessed routinely in primary care is incomplete, and such instruments cannot be excluded as a potential source of cross-infection.

Acetylcysteine↗

PubMed2005

Bridging and dimensions of sella turcica in subjects treated by surgical-orthodontic means or orthodontics only.

The aim of the study was to compare the incidence of sella turcica bridging and sella turcica dimensions in 150 Caucasian subjects who had combined surgical-orthodontic correction of their malocclusion with a randomly selected group of 150 Caucasian subjects who were treated contemporaneously by orthodontic means only. Pretreatment lateral cephalometric radiographs were scanned and analyzed. A sella turcica bridge was identified as a continuous band of bony tissue extending from the anterior cranial fossa to the posterior cranial fossa. The dimensions of the sella turcica were measured. In the group treated by combined surgical-orthodontic means, the incidence of bridging was 16.7%, whereas it was 7.3% in the orthodontics-only group (P = .012). Significant increases in the mean surface area (P = .02) and mean perimeter of the sella turcica (P = .01) were found for the combined surgical-orthodontic group compared with the orthodontics-only group. The mean interclinoid distance was significantly smaller in the surgical-orthodontic group (P = .02). These findings appear to indicate the greater likelihood of sella turcica bridging and abnormal sella turcica dimensions in subjects treated by combined surgical-orthodontic means rather than by orthodontics only.

Cephalometry↗

PubMed2004

In vitro dentine permeability: the relative effect of a dentine bonding agent on crown preparations.

OBJECTIVE: The aim of this study was to determine whether a dentine bonding agent (DBA) had an effect in reducing fluid filtration under cemented provisional crowns. METHODS: Crown preparations on 34 premolars, randomly allocated to two equal-sized test and control groups, were assessed for dentine permeability by a fluid filtration technique. In the test group, prepared crowns were acid-etched and then treated with a DBA (Prime & Bond NT). In the control group, no such DBA was applied. Provisional crowns were cemented on both groups of teeth using non-eugenol zinc oxide cement. Fluid filtration rates were measured repeatedly after crown preparation, at cementation, 1 h, 1 day, 1 week and 3 weeks following crown cementation for both groups. Filtration rates were also measured after acid-etching and dentine bonding for the test group. RESULTS: There was insufficient evidence to suggest any statistically significant differences either between the two groups or, on average, across the five time points in each group in terms of the relative percentage of fluid filtration. CONCLUSION: The DBA used did not seal dentinal tubules any more than did the smear layer and provisional crowns luted with a non-eugenol ZnO cement.

Acid Etching, Dental↗

PubMed2004

A partially blinded randomised controlled trial of patient-maintained propofol sedation and operator controlled midazolam sedation in third molar extractions.

Patient-maintained sedation using propofol has recently been shown to be effective for dental surgery. We compared this new technique to the established technique of operator administered midazolam. The two groups were compared before, during and after sedation. The two primary outcomes were time until discharge and oxygen saturation. Vital signs, anxiety and psychomotor skills were also compared. State anxiety was reduced to a greater extent in the propofol group (mean difference 10 (SD 4) mm; p = 0.010. Propofol patients recovered quicker (mean difference 7 (SD 1.4) min; p = 0.001). Propofol patients had a smaller reduction in arterial oxygen saturation (mean difference 0.8 (SD 0.3)%; p = 0.030), and a reduced increase in heart rate (mean difference 9 (SD 2) beats.min(-1); p < 0.001). Both techniques were well tolerated and safe. Propofol sedation offered superior anxiolysis, quicker recovery, less amnesia and less depression of simple psychomotor function.

Adolescent↗

PubMed2004

The validation of self-reported smoking status by analysing cotinine levels in stimulated and unstimulated saliva, serum and urine.

OBJECTIVES: Cotinine, a nicotine metabolite, can be used to measure exposure to tobacco smoke. The aim of this study was to compare cotinine levels in different biological fluids collected from both smokers and non-smokers and to relate the findings to self-reported smoking status. Data were also collected concerning the acceptability of the differing methods of sample collection. MATERIAL AND METHOD: Patients recruited to the study were asked to provide samples of urine, blood and saliva (both stimulated and unstimulated). Data collected from patients by questionnaire included information on smoking behaviour such as daily number of cigarettes and environmental exposure to smoke. After the sample collection, patients were asked to rate the acceptability of each sampling method. Samples were analysed using enzyme immunoassay (EIA) kits. RESULTS: In total, 80 patients participated, with 49 being smokers and 31 being non-smokers. There was clear differentiation between smokers and non-smokers (P < 0.001) for all the different samples in terms of cotinine. A significant relationship was seen between cotinine and daily number of cigarettes for both salivas and urine (all P < 0.001) but not for serum. Participants found serum and urine collection methodologies 'very acceptable' (67 and 66%, respectively) whereas 9% found collection of stimulated saliva 'not at all acceptable'. CONCLUSION: Cotinine, whatever the collection method and analysed by EIA kits, shows good differentiation between smokers and non-smokers. Salivary samples have the advantage of being non-invasive, although collection methodology is important, as cotinine levels may vary.

Adolescent↗

PubMed2004

Direct restorative materials use in Australia in 2002.

BACKGROUND: This study aimed to determine the reasons for dentists' choice of materials, in particular amalgam and resin composite, in Australia. METHOD: A questionnaire was developed to elicit this information. The names and addresses of 1000 dentists in Australia were selected at random. The questionnaire was mailed to these dentists with an explanatory letter and reply-paid envelope. RESULTS: A total of 560 replies were received. Regarding choice of material, 99 per cent of respondents cited clinical indication as an influencing factor, although patients' aesthetic demands (99 per cent of respondents), patients' wish (96 per cent), patients' financial situation (82 per cent), and lecturers' suggestions (72 per cent) were also reported to influence respondents' choice of materials. Twelve per cent of respondents used composite 'always', 29 per cent 'often', 32 per cent 'sometimes', 23 per cent 'seldom' and 4 per cent 'never' in extensive load-bearing cavities in molar teeth. For composite restorations in posterior teeth, 84 per cent 'always', 'often' or 'sometimes' used the total etch technique, 84 per cent used a thick glass-ionomer layer and 36 per cent never used rubber dam. Fifty-nine per cent of respondents reported a decreased use of amalgam over the previous five years. Sixty-eight per cent of respondents agreed with the statement 'discontinuation of amalgam restricts a dentist's ability to adequately treat patients'. Seventy-five per cent considered that the growth in the use of composites increased the total cost of oral health care. CONCLUSIONS: Of the respondents from Australia 73 per cent place large composite restorations in molar teeth and their choice of material is influenced greatly by clinical indications, and patients' aesthetic demands.

Acid Etching, Dental↗

PubMed2004

Use of dental photography by general dental practitioners in Great Britain.

This study assesses, by means of a postal questionnaire, the numbers of general dental practitioners who use clinical photography, and the uses to which this is applied. The questionnaire was distributed to 1000 randomly selected GDPs in Great Britain. A response rate of 76% was achieved. Of the respondents, 36% used clinical photography, with 65% of those using an intra-oral 35 mm camera, 18% a digital camera and 12% an intra-oral digital video camera. Principal uses of clinical photography were patient instruction/motivation (72%), medico-legal reasons (68%), treatment planning (63%), and liaison with laboratory (43%).

Communication↗

PubMed2003

Teaching periodontal pocket charting to dental students: a comparison of computer assisted learning and traditional tutorials.

AIM: The aim of this study was to compare the effectiveness of a computer assisted learning (CAL) programme with that of traditional small group tutorials in teaching theoretical and practical aspects of periodontal pocket charting. METHOD: Sixty-one third year undergraduate dental students were randomized to either receive a tutorial or to work through the CAL programme. Students using the CAL programme completed questionnaires relating to previous computer experience and the ease of use of the programme. All students were assessed immediately after the intervention by means of a confidence log, a practical exercise and a further confidence log. They were assessed again three weeks later by means of a confidence log and a multiple-choice written test. RESULTS: There were very few significant differences between groups for any of the assessments used. However, subjective comments indicated that students occasionally felt disadvantaged if they had not received a tutorial. CONCLUSION: CAL and traditional teaching methods are equally effective in teaching periodontal pocket charting to undergraduate dental students.

Clinical Competence↗

PubMed2003

Amalgam and composite use in UK general dental practice in 2001.

OBJECTIVE: This study determined the reasons for dentists' choice of materials, in particular amalgam and resin composite, in Great Britain. METHOD: A questionnaire was developed to elicit this information. The names and addresses of 1,000 UK-based dentists were selected at random. The questionnaire was mailed to these dentists with an explanatory letter and reply-paid envelope. RESULTS: Six hundred and fifty four replies were received. Regarding choice of material, 100% of respondents cited clinical indication as the most influential factor, although patients' aesthetic demands (99%), patients' choice (95%) and patients' financial situation (92%) were also reported to influence respondents' choice. Thirty-five per cent of respondents used composite 'sometimes', 15% 'often', and 1% 'always' in extensive load-bearing cavities in molar teeth. For composite restorations in posterior teeth, 92% 'always', 'often' or 'sometimes' used the total etch technique and 53% never used rubber dam. Seventy per cent of respondents agreed with the statement 'discontinuation of amalgam restricts a dentist's ability to adequately treat patients'. Eighty-one per cent considered that the growth in the use of composites increased the total cost of oral healthcare. CONCLUSIONS: Forty nine per cent of the respondents from England and Wales seldom or never place large composite restorations in molar teeth. Their choice of material is influenced greatly by clinical indications, and patients' aesthetic demands.

Acid Etching, Dental↗

PubMed2003

Evaluation of an oral health scoring system by dentists in general dental practice.

UNLABELLED: An Oral Health Index (OHX) has been designed to provide a numerical measure of the overall state of a patient's oral health by means of a series of simple clinical examinations. This has been amended to produce the Oral Health Score (OHS). OBJECTIVE: To assess, by means of a questionnaire, the ease of use and understanding of the OHS by general dental practitioners. METHODS: 350 GDPs were asked to participate in the project, of whom 329 agreed. These dentists were given a lecture of 2 hours' duration on the OHS. The participating dentists were requested to use the OHS for a period of 1 year. At the end of this period, a questionnaire was delivered to them by post, with an explanatory letter and reply-paid envelope. RESULTS: Completed, usable questionnaires were received from 239 GDPs, a 77% response rate. Ninety three percent of respondents considered the OHS instructions to be satisfactory. The respondents' views on the criteria on which the OHS component assessments are based indicated that over 90% of respondents agreed with the criteria for caries, adequacy of restorations, periodontal assessment, mucosal assessment and assessment of dentures. A majority of respondents agreed that the OHS provided a valid representation of oral health. CONCLUSION: The results of the present study indicate that the OHS is considered to be an easy-to-use measure of a patient's oral health and that it provides a valid representation of a patient's oral health.

Dental Health Surveys↗

PubMed2003

High prevalence of non-albicans yeasts and detection of anti-fungal resistance in the oral flora of patients with advanced cancer.

Oral fungal infections frequently develop in individuals with advanced cancer. This study examined the oral mycological flora of 207 patients receiving palliative care for advanced malignant disease. Demographic details and a clinical history were documented from each participant. A tongue swab was collected and cultured on CHROMAgar Candida (CHROMAgar Paris, France). All yeasts were identified by germ tube test, API ID 32C profiles and, for Candida dubliniensis, by species-specific PCR. Susceptibility to fluconazole and itraconazole was determined by a broth microdilution assay according to the National Committee for Clinical Laboratory Standards (NCCLS). At time of sampling, 54 (26%) of the 207 subjects had clinical evidence of a fungal infection and yeasts were isolated from 139 (67%) individuals. In total, 194 yeasts were isolated, of which 95 (49%) were Candida albicans. There was a high prevalence of Candidia glabrata (47 isolates) of which 34 (72%) were resistant to both fluconazole and itraconazole. All nine isolates of C. dubliniensis recovered were susceptible to both azoles. No relationship was established between anti-fungal usage in the preceding three months and the presence of azole resistant yeasts. This study of patients with advanced cancer has demonstrated a high incidence of oral colonization with non-C. albicans yeasts, many of which had reduced susceptibility to fluconazole and itraconazole. The role of improved oral care regimes and novel anti-fungal drugs merits further attention, to reduce the occurrence of fungal infection in these patients.

Adult↗

PubMed2002

A cross sectional study of water quality from dental unit water lines in dental practices in the West of Scotland.

OBJECTIVE: To determine the microbiological quality of water from dental units in a general practice setting and current practice for disinfection of units. DESIGN: A cross-sectional study of the water quality from 40 dental units in 39 general practices and a questionnaire of the disinfection protocols used in those practices. SETTING: NHS practices in primarydental care. SUBJECTS: Thirty-nine general practices from the West of Scotland. METHODS: Water samples were collected on two separate occasions from dental units and analysed for microbiological quality by the total viable count (TVC) method. Water specimens were collected from the triple syringe, high speed outlet, cup filler and surgery tap. Each participating practitioner was asked to complete a questionnaire. Results Microbial contamination was highest from the high speed outlet followed by the triple syringe and cup filler. On average, the TVC counts from the high speed water lines at 37 degrees C and for the high speed lines, triple syringe and cup filler at 22 degrees C were significantly higher than that from the control tap water specimens. The study included units from 11 different manufacturers with ages ranging from under one year to over eight years. The age of the dental unit analysed did not appear to influence the level of microbial contamination. Five of the practices surveyed used disinfectants to clean the dental units but these had no significant effect on the microbiological quality of the water. The majority of dental units (25 out of 40) were never flushed with water between patients. A number of different non-sterile irrigants were used for surgical procedures. CONCLUSION: The microbiological quality of water from dental units in general dental practice is poor compared with that from drinking water sources. Suitable sterile irrigants should be used for surgical procedures in dental practice. Further work is required for pragmatic decontamination regimens of dental unit water lines in a general dental practice setting

Colony Count, Microbial↗