Biomedical subjects

Graham J Roberts

Publications and source records attributed to Graham J Roberts.

11 recordsLinked to original sources

PubMed2006

The role for 'reminders' in dental traumatology: 4. The use of a computer database for recording dento-alveolar trauma in comparison to unstructured and structured paper-based methods.

The aims of this study were to investigate the effectiveness of a computer database (CD) developed for this study, a plain paper unstructured history (USH) and structured histories (SH) for the recording of important prognostic factors for simulated dento-alveolar trauma. Twelve vocational trainees, seven postgraduates in paediatric dentistry and 24 general dental practioners were randomly assigned to using USH, SH or CD. Each dentist visited a series of simulated trauma cases (with models, photos, radiographs and actors) and was asked to record important prognostic factors for each injury and make a diagnosis. There were a total of 243 dentist contacts with the trauma stations. The average percentage of important prognostic factors recorded per station was: USH 53%, SH 75.3% and CD 58.6%. SH was significantly better than the other two methods (P < 0.001, anova). Interestingly, those general dental practitioners (GDPs) who qualified prior to 1990 were significantly poorer at recording important prognostic information using CD. This effect was not obvious when using USH and SH. It was also seen that USH and SH were significantly better at helping clinicians reach a correct diagnosis as compared with CD (P < 0.001, chi-squared). A paper-based SH was the most effective method for collecting essential prognostic information for simulated trauma cases used in this study. At present, the introduction of our CD for recording of trauma is not justified without significant modification.

Chi-Square Distribution↗

PubMed2005

Oro-dental health in children with chronic renal failure and after renal transplantation: a clinical review.

As a consequence of chronic renal failure (CRF) and its treatment, a number of oro-dental changes occur that persist after the end-stage is reached. An early effect is enamel hypoplasia due to a defect of enamel development and mineralisation. This is usually reparable to a high aesthetic standard using dental composite filling material. Children with CRF have significantly less dental caries than healthy children due to the inhibitory effect of increased salivary urea levels. Grafted patients frequently develop gingival enlargement as a result of immunosuppression with cyclosporine A, which is further exacerbated by the additional use of antihypertensive calcium-blocking agents. Surgical reduction of gingival hyperplasia is effective and is required in approximately one third of adolescents. A very high standard of home care should be encouraged for all children with CRF in the form of thorough mechanical tooth cleaning and plaque inhibition through the use of an antibacterial mouthwash. In transplanted children presenting an increased risk of infection, antibiotic prophylaxis may be indicated for dental treatment procedures. The drug dosage should be adapted to the reduced renal function. Pediatric nephrologists should be aware that dental surgeons can make a considerable contribution to the general health and well-being of children with CRF. Thus, only oro-dental problems that are mainly encountered and treated by dental surgeons are reviewed.

Adolescent↗

PubMed2005

Statistical analyses of complex denaturing gradient gel electrophoresis profiles.

Studies using molecular techniques have demonstrated that a culture-based approach can severely underestimate the bacterial diversity in most environments. One of the molecular techniques that has been applied in microbial ecology is denaturing gradient gel electrophoresis (DGGE). The purpose of this study was to investigate differences in the microbiota of plaque, using a number of analysis techniques, from children without gingivitis (n = 30) and from those with gingivitis (n = 30). Extracted DNA from gingival margin plaque was subjected to PCR targeting the 16S rRNA gene using universal primers. DGGE profiles were analyzed in three ways. (i) Bacterial diversity was compared between cohorts by using the Shannon-Wiener index (also known as the Shannon-Weaver index). (ii) A hierarchical cluster analysis of the banding patterns was calculated and expressed as a dendrogram. (iii) Individual DGGE bands and their intensities for both cohorts were compared using a logistic regression analysis. The Shannon-Wiener indices demonstrated a greater bacterial diversity associated with no-gingivitis plaque (P = 0.009). Dendrograms demonstrated that seven clades associated with gingivitis and five clades associated with no gingivitis. The logistic regression demonstrated that one band was significantly associated with no gingivitis (P = 0.001), while two bands were significantly associated with gingivitis (P = 0.005 and P = 0.042). In conclusion, this study demonstrates that the development of gingivitis might be accompanied by a decrease in bacterial diversity. Furthermore, we have demonstrated that logistic regression is a good statistical method for analyzing and characterizing DGGE profiles.

Child↗

PubMed2004

Environmental influences on the trace element content of teeth--implications for disease and nutritional status.

The aim of this study was to compare the trace element content of children's primary teeth from Uganda and the UK. The Ugandan teeth were from children living in an area where endomyocardial fibrosis (EMF), a cardiac disease, is prevalent. The latter has been putatively linked to insufficient magnesium intake and excess cerium exposure. Primary teeth were collected from 21 Ugandan and 27 UK children. The crowns and roots of the teeth were separated and the former digested and analysed for several major and trace elements by inductively coupled plasma mass spectrometry (ICP-MS) and atomic emission spectrometry (ICP-AES). In addition, the enamel and dentine of eight UK and seven Ugandan primary teeth were isolated via density separation and analysed as above. The data were assessed using non-parametric statistical tests. The Ugandan teeth contained significantly (P < 0.05) greater concentrations of strontium, barium, cerium, lanthanum, praseodymium and significantly less zinc than the UK teeth. No significant difference in the concentrations of aluminium, calcium, copper, magnesium, lead and uranium were found. Analysis of enamel and dentine demonstrated that the former was enriched with several elements including cerium. It is concluded, that the environment, influences the trace element content of primary teeth and this may be useful for monitoring nutritional status. With respect to a geochemical cause for EMF, there is no positive evidence that EMF in Uganda is associated with reduced magnesium and increased cerium uptake in primary teeth. This does not, however, exclude cerium from playing a role in the aetiology of EMF.

Adolescent↗

PubMed2004

Prevalence of periodontal pathogens in dental plaque of children.

Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, and Tannerella forsythensis have been implicated as the main etiological agents of periodontal disease. The purpose of this work was to estimate the prevalence of these organisms in plaque from children without gingivitis (group 1; n = 65) and from those with gingivitis (group 2; n = 53). Extracted DNA from plaque was subjected to two rounds of PCR targeting the 16S rRNA gene using both universal primers and species-specific primers. The results were as follows: group 1, P. gingivalis, 49%; A. actinomycetemcomitans, 55%; and T. forsythensis, 65%; group 2, P. gingivalis, 47%; A. actinomycetemcomitans, 59%; and T. forsythensis, 45%. T. forsythensis was detected more frequently in children with no gingivitis than in those with gingivitis (P = 0.03). There was no significant difference between the two groups with respect to the presence of P. gingivalis or A. actinomycetemcomitans in either group (P > 0.05). Logistic regression analysis revealed that the odds of a patient having gingivitis were 2.3 times greater in the absence of T. forsythensis. In conclusion, the results of this study have shown that the three pathogens can be detected in the dental plaque of healthy children and of those with gingivitis and that T. forsythensis is associated with dental plaque at sites with no gingivitis.

Aggregatibacter actinomycetemcomitans↗

PubMed2004

Oral health of children with juvenile idiopathic arthritis.

OBJECTIVE: s. To estimate dental disease indices and temporomandibular joint (TMJ) dysfunction in children with juvenile idiopathic arthritis (JIA). METHODS: Indices were recorded for dental caries, bacterial dental plaque, gingival inflammation, and TMJ dysfunction in children with JIA and matched controls. RESULTS: There was no significant difference in dental caries experience or the mean plaque score between children with JIA and controls. The mean gingivitis score for the permanent teeth only was significantly greater in the JIA children compared with the controls (p = 0.02). There was a significantly greater proportion of children with JIA with signs of both left and right TMJ dysfunction (p = 0.05, p = 0.02) and symptoms (p = 0.0001, p = 0.0001) compared with controls. CONCLUSION: The low caries rate was attributed to the fact that children with JIA had received preventive dental care from an early age combined with sugar free medication.

Arthritis, Juvenile↗

PubMed2002

Oral health in children with chronic renal failure.

Seventy children with chronic renal failure (CRF) aged 4-13.6 years were recruited from the Renal Unit of the Great Ormond Street Hospital for Children. Indices were recorded for dental caries, dental plaque, gingival inflammation, gingival enlargement, and enamel defects. Salivary urea, buffering capacity, and the oral streptococcal flora were determined for 25 of the children. A significantly greater proportion of the CRF children was caries free, 40% compared with 8.5% of the controls. The mean plaque score was significantly greater in the CRF group for both the primary 12.7 (16) and permanent dentition 22.0 (18.2) compared with the controls, 5.3 (7.6) and 15.5 (13.3), respectively. Eight CRF children had gingival enlargement. Enamel defects affecting the permanent teeth were observed in 57% of the CRF children compared with 33% of the controls. The buffering capacity was significantly greater in the CRF group, pH 6.4 (0.5) compared with the controls pH 5.6 (0.8). The mean salivary urea level (mmol/l) was significantly greater in the CRF children, 11.6 (5.9) compared with 3.6 (1.4) for the controls. The isolation frequency of Streptococcus mutans was significantly greater from controls compared with the CRF children ( P=0.002). An integrated dental service needs to be developed with emphasis on tooth brushing to prevent gingival hyperplasia and periodontal disease after puberty.

Adolescent↗

PubMed2002

A sampling and analytical methodology for dental trace element analysis.

The role of trace elements in human health and environmental pollution has developed into an extensive field of research. This study describes a sampling and analytical strategy to determine the trace element content of primary (deciduous) teeth and to assess their use in environmental health and nutrition studies. Exfoliated and extracted primary teeth were collected from 21 Ugandan and 27 UK children. The crown and root of the teeth were separated and the former digested and analysed for several elements by inductively coupled plasma mass spectrometry. The influence of country, tooth type, age and gender were statistically investigated in addition to within-person variation. A principal components analysis (PCA) was used to treat the data in a multivariate fashion and facilitated the moderation of outliers. The results demonstrated that country of origin has an important influence on the elemental composition of teeth and that tooth type should be controlled in these types of studies. Given such a restriction, the age and gender of the donor should have no effect and do not need to be controlled. In addition, where country of domicile, age and gender were controlled, the concentrations of most elements within a single tooth type were representative of an individual and therefore may be indicative of health status.

Child↗

PubMed2002

The relationship between odontogenic bacteraemia and orthodontic treatment procedures.

The purpose of this research was to estimate the prevalence and intensity of bacteraemia associated with orthodontic treatment procedures. The four procedures investigated were: an upper alginate impression, separator placement, band placement, and adjustment of an archwire on a fixed appliance. Eighty-one children undergoing general anaesthesia (GA) for dento-alveolar surgery related to their orthodontic treatment were randomly allocated to the impression or separator group. A further 61 children, receiving treatment in the Outpatient Department, were included and randomly allocated to the banding or archwire adjustment groups. A cannula was inserted into either the left or right antecubital fossa using an aseptic technique. A baseline 6 ml sample of blood was taken before treatment and a second 6 ml sample was taken 30 seconds after the procedure. There was no significant difference in the number of positive blood cultures between baseline (nine, 23 per cent), and following an upper alginate impression (twelve, 31 per cent); between baseline (twelve, 27 per cent), and placement of a separator (fifteen, 36 per cent); between baseline (nine, 36 per cent), and fitting or placement of a band (eleven, 44 per cent); or between baseline (twelve, 33 per cent), and archwire adjustment (seven, 19.4 per cent). For the separator group only the mean total number of aerobic and anaerobic bacteria combined, isolated from the blood samples (cfu of bacteria per ml of blood), was significantly greater following the placement of a separator (2.2, SD 9.1), compared with baseline (0.9, SD 0.2; P < 0.02). This investigation demonstrates that the only orthodontic treatment procedure that causes a significant bacteraemia is the placement of a separator.

Adolescent↗

PubMed2002

Comparison of lysis filtration and an automated blood culture system (BACTEC) for detection, quantification, and identification of odontogenic bacteremia in children.

Lysis filtration (LyF) was compared with BACTEC PAEDS PLUS in estimating the prevalence of, and sensitivity for, detection of odontogenic bacteremia. Both real bacteremia and simulated bacteremia (seeded blood or saline samples) were assessed to determine the validity of LyF in estimating bacteremia. The simulated bacteremia was also used to assess the reliability of LyF to estimate intensity of bacteremia in CFU per milliliter of blood. Reference organisms were used to assess the abilities of LyF and BACTEC to isolate known oral streptococci. There was no difference in the number of CFU per milliliter of seeded saline, seeded blood, and drop cultures of the organisms plated directly onto agar. Blood cell volume had a negligible effect on the yield of organisms for simulated bacteremia. When LyF and BACTEC were compared, the time to detection of bacteremia was always significantly shorter for BACTEC. For aerobic cultures, these times were 43.7 and 9.6 h, respectively (P < 0.01). For anaerobic cultures, these times were 45.1 and 9.9 h, respectively (P < 0.01). These differences occurred as well for bacteremia following the extraction of a single tooth, with LyF and BACTEC aerobic cultures taking 78 and 30.5 h, respectively (P < 0.0001). For anaerobic cultures, the times were 90.8 and 45 h, respectively (P < 0.0004). A preextraction bacteremia was detected on 2.1% of occasions with BACTEC compared to 31% of occasions with LyF (P < 0.05) The use of LyF was an effective and reliable means of estimating the intensity of pre- and postextraction bacteremia. The values were 3.6 and 5.9 CFU/ml, respectively (P < 0.4729), and the difference was not statistically significant. In summary, BACTEC is quicker than LyF, but less sensitive. LyF provides additional important information in estimating the intensity of bacteremia.

Adolescent↗

PubMed2002

Advances in paediatric dentistry.

The problems facing paediatric dentists have not changed over the years, management of caries and orodental trauma still takes up the greatest proportion of their time. What has changed are the treatments available and in this paper some of the more interesting recent developments in this field are summarised.

Behavior Therapy↗