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Biomedical subjects

David R Moles

Publications and source records attributed to David R Moles.

At least 19 recordsLinked to original sources
PubMed2007

Human herpesvirus 8 genoprevalence in populations at disparate risks of Kaposi's sarcoma.

The prevalence of human herpesvirus 8 (HHV-8) in populations at different risks of developing Kaposi's sarcoma (KS) was assessed using a protocol involving immunomagnetic fractionation of CD45+ blood cells prior to detection of the HHV-8 genome by nested PCR. Preliminary studies using blood of eight gay men infected by human immunodeficiency virus-1 (HIV-1) revealed that, for the detection of HHV-8 DNA derived from open reading frame (ORF) 26 of the HHV-8 genome, this protocol provided substantially higher rates (100%) compared to one involving red blood cell (RBC) lysis (0%) and to another requiring double density gradient centrifugation (DDGC) of leukocytes (13%). When the CD45+ fractionation protocol was applied to samples from 103 other HIV-1-infected patients (the vast majority of whom were gay men) and 100 blood donors, the ORF 26 DNA detection rates obtained were 37% and 8%, respectively. When DNA from the variable region 1 of ORF K1 was additionally amplified from samples of the blood donors, a detection rate of 9% was achieved. This rate was highly concordant with the ORF 26 DNA detection rate. Furthermore, the ORF K1 sequences were predominantly unique, assignable to genotypes A1, A4, and C3. When assays for anti-HHV-8 and anti-herpes simplex viruses (HSV) 1 and 2 were applied, significant concordances between HHV-8 DNA detection rates and those relating to anti-HHV-8 and to anti-HSV 1 and 2 were more frequently observed for HIV-1-infected patients than for blood donors. The higher-than-expected HHV-8 genoprevalence rate in blood donors requires further confirmation in view of its implications for post-transfusion HHV-8 transmission.

Acquired Immunodeficiency Syndrome↗
PubMed2006

A systematic review of measures of effectiveness in screening for oral cancer and precancer.

Nine databases were searched for studies reporting a range of measures on the effectiveness of screening for oral cancer and precancer in primary care. Of 1114 papers generated in a search of nine databases, full texts of 90 were scrutinised by two reviewers to ensure that they were concerned with oral cancer/precancer, reported an oral cancer screening programme/exercise and included at least one effectiveness outcome. Criteria for considering studies for the review covered types of studies, participants, interventions and outcome measures. The latter included measures of both end point and interim outcome and also process. Of 90 full text articles screened, examiners agreed on the inclusion of 28 (initial agreement -- kappa=0.60). The remaining 62 were excluded and the reasons recorded. The studies included showed substantial heterogeneity regarding objectives and study design, location and setting, numbers and characteristics of participants, screening personnel, methods of recruitment and types of data collected. Only one study, from the Indian sub-continent, reported a randomised controlled trial: interim results showed 14.9% of intervention subjects died after 3 years compared with 56.3% of non-intervention controls. The review overall produced no evidence in favour of or against the potential benefits associated with an oral cancer screening programme. It was concluded that there are insufficient available data to make an unequivocal determination as to the effectiveness of oral cancer screening programmes at the present time. However, a recent further report on the Indian study published after completion of the review, provides some evidence that screening for oral cancer may be effective, at least in developing countries with a high incidence of the disease.

Humans↗
PubMed2006

The effect of disinfection on irreversible hydrocolloid and type III gypsum casts.

Under standardised conditions, 80 impressions were made of a ruled stainless steel die (ISO Specification 1563) using irreversible hydrocolloid (alginate). The alginates were subsequently treated with 3 commercially available disinfectants, Perform-ID, ImpressiVand Dimenol and poured with type III gypsum. The alginates were evaluated for surface detail reproduction and the gypsum for surface detail reproduction and hardness. Disinfection with Perform ID significantly affected the surface detail reproduction of alginate while Dimenol and ImpressiV did not. Perform ID and Dimenol both significantly affect the hardness of poured type III gypsum casts while ImpressiV did not.

Alginates↗
PubMed2006

Influence of surface treatments on the shear bond strength of Panavia 21 to a Type III gold alloy.

Cylinders of Type III gold alloy were sandblasted with either: 50 micron Aluminium Oxide particles (Group 1); CoJet Sand (Group 2); the CoJet System - CoJet Sand followed by application of silane primer (Group 3). Shear testing was undertaken following apposition of Panavia 21 resin. Mean shear bond strengths (+/- standard deviation) were Group 1, 32.9 (+/-18.2) MPa; Group 2, 26.5 (+/-10.8) MPa and Group 3, 45.6 (+/- 25.8) MPa. There was no statistically difference between Group 1 and 2; and between group 1 and 3. However, there was a significant; difference between Group 2 and 3 p < 0.05). While the CoJet System achieved the highest mean shear bond strength it conveyed no statistical advantage over the traditional method of sandblasting with aluminium oxide.

Aluminum Oxide↗
PubMed2005

Type IV gypsum compatibility with five addition-reaction silicone impression materials.

STATEMENT OF PROBLEM: The compatibility of current addition-reaction silicone impression materials and Type IV gypsum products is not completely understood. PURPOSE: The purpose of this study was to compare surface detail reproduction between various combinations of contemporary addition-reaction silicone impression materials and Type IV gypsum products. MATERIAL AND METHODS: Under standardized conditions, 300 impressions were made of a ruled stainless steel die (ADA specification 19), using 5 addition-reaction silicones (Examix-NDS, Doric-ES Flo-Light, Panasil Contact Plus, Extrude Wash, and President Plus Jet). Fifteen impressions of each material were poured with each Type IV gypsum product (Silky-Rock, Fuji Rock, Suprastone, or Vel-Mix). Using x12 magnification, 2 independent examiners scored the reproducibility of a 20-microm line in both the impression and the resultant casts. Statistical analysis was performed using 2-way analysis of variance and post hoc Bonferroni testing (alpha = .05). RESULTS: All impression materials tested fully reproduced the 20-microm line. Different impression materials showed different compatibility with different Type IV gypsum products. Only 25% of the Type IV gypsum casts completely reproduced the resultant 20-microm line with fine margins, and 88% of the completely reproduced casts were made from Suprastone. CONCLUSION: Not all combinations of impression material and Type IV gypsum products used exhibited similar compatibility.

Analysis of Variance↗
PubMed2005

Susceptibilties of two Enterococcus faecalis phenotypes to root canal medications.

This study aimed to investigate and compare the efficacy of selected root canal irrigants and a medicament on a clinical isolate of Enterococcus faecalis grown as biofilm or planktonic suspension phenotype. A cell-dense pellet "presentation" prepared from planktonic phenotype was also tested. Each bacterial presentation was exposed to calcium hydroxide (pH 12.3), 0.2% chlorhexidine gluconate, 17% ethylene-diamine-tetra-acetic acid, 10% povidone iodine, or 3.0% sodium hypochlorite (NaOCl) for a range of time periods (1, 2, 4, 8, 15, 30, and 60 min). Phosphate buffered saline was used as a control agent. The difference in gradients of bacterial killing among the biofilm, planktonic suspension or pellet presentation was significant (p < 0.05) and dependent upon the test agent except in the case of NaOCl and calcium hydroxide where no difference could be detected. NaOCl was the most effective agent and achieved 100% kills for all presentations of E. faecalis after a 2 min contact time.

Biofilms↗
PubMed2005

A systematic review of professional mechanical plaque removal for prevention of periodontal diseases.

AIM: To investigate the effect of professional mechanical plaque removal (PMPR) on the prevention of periodontal diseases. METHODS: We searched for randomized controlled trials, controlled clinical trials and cohort studies from 1950 to October 2004. Screening and data abstraction were conducted independently and in duplicate. Critical appraisal of studies was based on objective criteria and evidence tables were constructed. RESULTS: From 2179 titles and abstracts, 132 full-text articles were screened and 32 studies were relevant. Evidence exists that PMPR in adults, particularly in combination with oral hygiene instruction (OHI), may be more effective than no treatment judged by surrogate measures. The evidence for a benefit of PMPR+OHI over OHI alone is less clear. The optimum frequency of PMPR has not been investigated although more frequent PMPR is associated with improved markers of health. The strength of evidence for these results ranges from weak to moderate due to risk of bias, inconsistent results, lack of appropriate statistics and small sample size. CONCLUSIONS: There appears to be little value in providing PMPR without OHI. In fact, repeated OHI might have a similar effect as PMPR. Some forms of PMPR might achieve greater patient satisfaction. There is little difference in beneficial or adverse effects of different methods of PMPR.

Adult↗
PubMed2005

Adjunctive benefits of systemic amoxicillin and metronidazole in non-surgical treatment of generalized aggressive periodontitis: a randomized placebo-controlled clinical trial.

BACKGROUND: The objective of this study was to assess the adjunctive clinical effect of the administration of systemic amoxicillin and metronidazole in the non-surgical treatment of generalized aggressive periodontitis (GAP). METHODS: Forty-one systemically healthy subjects with GAP were included in this 6-month double-blind, placebo-controlled, randomized clinical trial. Patients received a course of full-mouth non-surgical periodontal treatment delivered over a 24 h period using machine-driven and hand instruments. Test subjects received an adjunctive course of systemic antibiotic consisting of 500 mg amoxicillin and 500 mg metronidazole three times a day for 7 days. Clinical parameters were collected at baseline, and at 2 and 6 months post-treatment. RESULTS: In both the test and the placebo groups, all clinical parameters improved at 2 and 6 months. In deep pockets (> or =7 mm), the test treatment resulted in an additional 1.4 mm (95% confidence interval 0.8, 2.0 mm) in full-mouth probing pocket depth (PPD) reduction and 1 mm (0.7, 1.3 mm) of life cumulative attachment loss (LCAL) gain at 6 months. In moderate pockets (4-6 mm), the adjunctive benefit was smaller in magnitude: PPD reduction was 0.4 mm (0.1, 0.7 mm) and LCAL gain was 0.5 mm (0.2, 0.8 mm). In addition, the 6-month data showed LCAL gains > or =2 mm at 25% of sites in test patients compared with 16% in placebo (p=0.028). Similarly, PPD reductions of 2 mm or more were observed in 30% of sites in test and 21% of sites in placebo patients. Seventy-four percent of pockets with PPD > or =5 mm at baseline were 4 mm or shallower at 6 months in the test group. This compared with 54% in the placebo group (p=0.008). Disease progression at 6 months was observed at 1.5% of test and 3.3% of sites in test and placebo, respectively (p=0.072). CONCLUSIONS: These data indicate that a 7-day adjunctive course of systemic metronidazole and amoxicillin significantly improved the short-term clinical outcomes of full-mouth non-surgical periodontal debridement in subjects with GAP.

Adolescent↗
PubMed2005

Brightness (value) sequence for the Vita Lumin Classic shade guide reassessed.

The purpose of this study was to locate the 16 shade tabs from the Vita Lumin 'Classic' shade guide within the quantitative Luminosity, R, G and B scales (0-255 scales) using Photoshop software. A new value order arranged according to the Photoshop scale demonstrated a more linear relationship between the 16 shade tabs than the order given by the manufacturer. A Brightness Index representing the percentage difference in value between pairs of reordered shade tabs is suggested as a more realistic determinant of change in shade tab value.

Image Processing, Computer-Assisted↗
PubMed2004

A systematic review of test performance in screening for oral cancer and precancer.

Nine databases were searched for studies on test performance in screening for oral cancer and precancer in primary care. Of 481 papers, full texts of 47 were scrutinised by two reviewers. Only prospective investigations of population screening involving examination of the oral mucosa, with gold standard verification (examination by an expert of subjects screened positive and at least a proportion of negatives), were selected. Seven papers describing eight studies were finally included (kappa=0.83). The weighted pooled value of sensitivity, from random effects meta-analysis, was 0.848 (95% CI 0.730, 0.919). The corresponding value for specificity was 0.965 (95% CI 0.930, 0.982). Main sources of clinical heterogeneity occurred between large house-to-house case finding programmes from SE Asia, utilising primary health workers, and smaller studies from England and Japan. Meta-analysis regression showed no difference (P=0.99) in the generally high level of discriminatory ability of the test between these two groups.

Area Under Curve↗
PubMed2004

A comparison of yield in a non-systematic and a systematic review.

OBJECTIVES: To compare the results of a non-systematic (A) and a systematic review (B) of test performance in oral cancer and precancer screening in terms of literature coverage, and qualitative and quantitative information yield. METHOD: For A, two databases were searched using basic search terms. Review B followed published guidelines. Nine databases were searched using three complex facets. In both reviews, one reviewer made the initial selection of relevant studies and, in A, carried out full text screening. In B, two independent reviewers carried out full text screening and then conferred on a final list of studies for inclusion and meta-analysis. RESULTS: In search A, 60 papers, and in B, 481 papers, were retrieved. Thirty from A, and 47 from B were selected for full text screening. From A, six papers, and from B, eight papers (six selected by the first reviewer and eight by the second; kappa = 0.83), were designated for inclusion in meta-analysis. The six papers from A were common to all selections. Seven papers were finally included in B. Compared with the non-systematic review, meta-analysis in the systematic review reduced the 95% CI for sensitivity from 0.594, 0.912 (= 0.318) to 0.713, 0.919 (= 0.189) resulting from the inclusion of a larger number of verified cases. The 95% CI for specificity changed only from 0.941, 0.991 (= 0.050) to 0.930, 0.982 (= 0.052). DISCUSSION: Both reviews had the same exacting and specific inclusion criteria. The papers ultimately included in each were closely matched. Advantages of the systematic review were 1) it afforded a degree of confidence that the literature had been exhaustively and systematically searched, 2) the use of a formal data extraction process ensured that clinical heterogeneity among the studies and its consequences were thoroughly explored, 3) the increased number of verified cases included in the systematic review meta-analysis led to the pooled estimate for sensitivity having greater precision.

Confidence Intervals↗
PubMed2002

A retrospective comparison of outcome of root canal treatment using two different protocols.

OBJECTIVES: This retrospective study (1) compared the outcome of root canal treatment performed by an endodontist using 1 of 2 different protocols and (2) evaluated the influence of factors affecting outcome. STUDY DESIGN: A total of 200 teeth and 489 roots (Protocol A, 83 teeth/200 roots; Protocol B, 117 teeth/289 roots) treated nonsurgically with root canal 4 to 5 years previously were examined clinically and radiographically according to strict criteria. Generalized estimating equations were used to perform logistic regression to analyze data. RESULTS: The rate of complete healing for Protocol A (78%) was similar to that of Protocol B (76%). The pulpal status (odds ratio = 2.399, P =.040) and presence (odds ratio = 1.696, P = 0.015) and size (odds ratio = 0.823, P <.001) of periapical lesion were the only factors significantly affecting treatment outcome. CONCLUSION: The preoperative status of the pulp and the presence and extent of periapical periodontitis were important prognostic determinants of treatment outcome in this study.

Adult↗