Biomedical subjects

Karen Williams

Publications and source records attributed to Karen Williams.

32 records · Page 2Linked to original sources

PubMed2003

A plaque removal study comparing two advanced-design oscillating battery-powered toothbrushes.

OBJECTIVE: The objective of this study was to compare the plaque removal efficacy of two advanced-design battery-powered toothbrushes (Crest SpinBrush Pro and Oral-B CrossAction Power) following a single use. METHODOLOGY: This study was a randomized, controlled, examiner-blind, four-period crossover design, which examined plaque removal with the two toothbrushes following a single use by 40 subjects. Plaque was scored before and after brushing using the Turesky Modification of the Quigley-Hein Index. RESULTS: Average baseline plaque scores were 2.915 and 2.883 for the SpinBrush Pro and CrossAction Power toothbrush treatments, respectively. The SpinBrush Pro toothbrush delivered an adjusted (via analysis of covariance) mean difference between baseline and post-brushing plaque scores of 0.802, while the CrossAction Power toothbrush delivered an adjusted mean difference of 0.667. The SpinBrush Pro toothbrush, on average, had 20.2% greater plaque removal scores relative to the CrossAction Power toothbrush. These results were statistically significant (p < 0.001). The observed results on the buccal and lingual surfaces were consistent with the overall results, and were statistically significant. CONCLUSION: The results of this study support the conclusion that the SpinBrush Pro removes statistically significantly greater amounts of plaque over a one-minute brushing period compared to the CrossAction Power toothbrush.

Adult↗

PubMed2003

Early childhood caries in an urban health department: an exploratory study.

PURPOSE: The purpose of this investigation was to assess the prevalence of early childhood caries (ECC) as a function of various ECC case definitions, in a population of children ages one to five, attending a Women, Infants, and Children (WIC) or well-child clinic at an urban health department. Additionally, the study examines the association of sociodemographic factors, caregiver's oral health perceptions, resources, feeding and oral care behaviors, and prenatal and perinatal histories as risk factors for early childhood caries. METHOD: A convenience sample of 74 children ages one to five years and their parent(s) or guardian(s) enrolled in the WIC and Well Child Services Program at the Kansas City Health Department participated in this study. Caries experience and developmental enamel defects of children were assessed utilizing the deft and linear enamel hypoplasia (LEH) indices. Additionally, the children's parents of guardians were asked to complete a questionnaire to collect data on predisposing risk factors. RESULTS: The proportion of all children with evidence of Type I ECC was high (31.5%), with all ethnic minority groups having a large proportion with caries. Four of the predisposing risk factor variables were related (p < 0.05) to presence of ECC-child's age, gender, age at weaning, and frequency of sweet drinks. Child's age and age at weaning were related to a significant increase in risk for caries when these effects were adjusted by the effect of other risk factor variables. The odds of having caries were increased by 2.3 times (95%, CI 1.4, 3.9) for each increase in child's age by year, and by 2.8 times (95%, CI 1.5, 5.2) for each incremental increase in age category for the child at weaning. CONCLUSION: This investigation lends further support to the contention that quantifying the occurrence of ECC is likely dependent and complicated by diverse case definitions. Caregiver's perceptions of their child's oral health were generally accurate, thereby supporting proponents for educational and preventive strategies aimed at the parent/guardian.

Bottle Feeding↗

PubMed2002

How does time-dependent dental unit waterline flushing affect planktonic bacteria levels?

The purpose of this study was to evaluate how time-dependent waterline flushing affects the presence of biofilm in otherwise-untreated dental unit waterlines (DUWLs). Water samples were obtained from twelve highspeed handpiece DUWLs located in the undergraduate treatment clinic at the University of Missouri-Kansas City, School of Dentistry. Baseline water samples (50 cc) were collected prior to the start of continuous flushing. Additional 50 cc samples were collected after two-, three-, and four-minute flushing intervals from the baseline. The levels of planktonic bacteria in DUWLs were quantified by counting colony forming units (CFUs). In addition, segments of water tubing from each of the highspeed handpiece waterlines were examined by scanning electron microscopy, which confirmed the presence of a residual biofilm in the lumen of each dental unit waterline. A one-factor repeated measures ANOVA showed a statistically significant (p<0.01) reduction in CFUs at all intervals compared to baseline and between each successive time interval. Indeed, after four minutes of continuous flushing, all waterlines still harbored CFU levels that exceed current American Dental Association (ADA) recommendations. It was concluded that water flushing of DUWLs produced a statistically significant reduction in planktonic bacteria at each time interval compared to the baseline and between each successive time interval. However, the level of CFUs after four minutes of continuous water flushing still exceeds the current ADA recommendations for acceptable levels of microorganisms.

Analysis of Variance↗

PubMed2002

Plaque removal efficacy of a new experimental battery-powered toothbrush relative to two advanced-design manual toothbrushes.

The current study was designed to assess the plaque removal efficacy of a novel experimental powered toothbrush (Crest SpinBrush Pro) compared to two leading manual toothbrushes, the Oral-B CrossAction and the Colgate Navigator. In addition, this paper reports the results of two additional studies examining the relative plaque removal efficacy of the two control manual toothbrushes and a number of other manual toothbrushes. The comparative study was a randomized, controlled, examiner-blind, nine-period crossover design, conducted among 127 adult subjects over a two-month period, that examined plaque removal with a new battery-powered toothbrush and two advanced-design manual toothbrushes. During the course of this study, subjects brushed three times with the experimental powered toothbrush and three times with each control manual toothbrush. Study participation was on a voluntary basis following written informed consent of the subjects. Plaque was scored before and after brushing using the Turesky, et al. Modification of the Quigley-Hein Index. Average baseline plaque scores were 2.68 to 2.69 for the three treatment groups. The experimental toothbrush delivered an adjusted (via analysis of covariance) mean difference between baseline and post-brushing plaque scores (i.e., a plaque removal score) of 0.69, while the control toothbrushes delivered adjusted mean differences of 0.46 (Colgate Navigator) and 0.54 (Oral-B CrossAction). All group differences were statistically significant (p < 0.001). The experimental powered toothbrush group had, on average, 49% and 28% greater plaque removal scores than the Colgate Navigator and Oral-B CrossAction groups, respectively. In addition, the Oral-B CrossAction group had, on average, a 16% greater plaque removal score than the Colgate Navigator group. This result was also statistically significant (p < 0.001). Results on buccal and lingual surfaces also demonstrated statistically significantly (p < 0.001) greater plaque removal for the experimental battery-powered toothbrush relative to the control manual toothbrushes.

Adolescent↗

PubMed2002

The reduction of gingivitis using battery-powered toothbrushes over a one-month period.

This study measured the ability of two powered toothbrushes (Crest SpinBrush and Crest SpinBrush Pro) to reduce gingivitis relative to baseline levels over a one-month period. This study made use of a randomized, controlled, examiner-blind, parallel design. Subjects were examined for Löe-Silness GI scores at baseline and at one month. The primary efficacy variable was GI score change at one month from the baseline GI score. Within-group comparisons to baseline were performed using paired t-tests. Secondarily, treatment group differences were examined using an analysis of covariance model, with baseline as the covariate. Separate analyses were performed for Löe-Silness GI scores and for the number of gingival bleeding sites. All comparisons were two-sided and used the 0.05 level of significance. A total of 87 subjects completed the study. Of these, there were 57 females and 30 males, ranging in age from 18 to 70 years with a mean age of 33.1 years. Baseline GI scores were 0.487 and 0.449 for the Crest SpinBrush and Crest SpinBrush Pro, respectively, and were not statistically significantly different. Both brushes demonstrated highly statistically significant reductions in GI vs. baseline (all p < 0.001), and delivered an approximately 60% reduction in GI. Baseline bleeding site scores were 37.6 and 34.4 for the Crest SpinBrush and Crest SpinBrush Pro, respectively, and were not statistically significantly different. Both brushes demonstrated highly statistically significant reductions in bleeding vs. baseline (all p < 0.001), and delivered an approximately 60% reduction in bleeding sites. None of the ANCOVA comparisons between brush groups were statistically significant (all p > or = 0.354). Both the Crest SpinBrush Pro and Crest SpinBrush powered toothbrushes were highly effective at reducing gingivitis when used per manufacturer's instructions.

Adolescent↗

PubMed2002

Bathing aid options.

Explore the source record for details and available documents.

Activities of Daily Living↗

PubMedDate not supplied

Comparison of five antimicrobial regimens for treatment of mild to moderate inflammatory facial acne vulgaris in the community: randomised controlled trial.

BACKGROUND: We investigated the efficacy and cost-effectiveness of five antimicrobial regimens for mild to moderate facial acne and whether propionibacterial antibiotic resistance affects treatment response. METHODS: In this randomised, observer-masked trial, 649 community participants were allocated one of five antibacterial regimens. Primary outcomes were patients' self-assessed improvement and reduction in inflamed lesions at 18 weeks. Analyses were by intention to treat. FINDINGS: Moderate or greater improvement at 18 weeks was reported in 72 (55%) of 131 participants assigned oral oxytetracycline plus topical placebo, 70 (54%) of 130 assigned oral minocycline plus topical placebo, 78 (60%) of 130 assigned topical benzoyl peroxide plus oral placebo, 84 (66%) of 127 assigned topical erythromycin and benzoyl peroxide in a combined formulation plus oral placebo, and 82 (63%) of 131 assigned topical erythromycin and benzoyl peroxide separately plus oral placebo. Most improvement occurred in the first 6 weeks. Treatment differences for the proportion of people with at least moderate improvement were: minocycline versus oxytetracycline -1.2% (unadjusted 95% CI -13.3 to 10.9); combined erythromycin and benzoyl peroxide versus oxytetracycline 11.1% (-0.7 to 22.9) and versus minocycline 12.3% (0.4 to 24.2); erythromycin and benzoyl peroxide separately versus combined formulation -3.5% (-15.2 to 8.2); benzoyl peroxide versus oxytetracycline 5.0% (-7.0 to 17.0), versus minocycline 6.2% (-5.8 to 18.2), and versus combined formulation -6.1% (-17.9 to 5.7). Benzoyl peroxide was the most cost-effective treatment. Efficacy of both tetracyclines was reduced by pre-existing tetracycline resistance. INTERPRETATION: Topical benzoyl peroxide and benzoyl peroxide/erythromycin combinations are similar in efficacy to oral oxytetracycline and minocycline and are not affected by propionibacterial antibiotic resistance.

Acne Vulgaris↗

PubMedDate not supplied

Histomorphologic characterization of noncarious and caries-affected dentin/adhesive interfaces.

PURPOSE: The purpose of this study was to compare the dentin/adhesive interfacial characteristics when bonding to noncarious as well as caries-affected dentin. MATERIALS AND METHODS: Seven extracted, unerupted, third molars were sectioned into halves. Artificial caries was created on one-half of each tooth, leaving the other half as a control. Dentin surfaces were treated with UNO adhesive according to the manufacturer's instructions for the wet-bonding technique and under environmental conditions present in the oral cavity. Dentin/adhesive interface sections of each half-tooth were stained with Goldner's trichrome, a classic bone stain, and examined using light microscopy. The width of exposed collagen was measured directly from photomicrographs, and adhesive penetration was analyzed qualitatively. RESULTS: The degree and extent to which the adhesive encapsulated the demineralized dentin matrix were reflected in the color difference in the stained sections with the noncarious dentin sections showing a degree of collagen encapsulation superior to that of the caries-affected dentin sections. The overall mean widths of exposed collagen were significantly (p < or = .05) greater at the caries-affected dentin/adhesive interface, 8.6 (1.7) microm, as compared with those at the noncarious dentin/adhesive interface, 6.0 (1.5) microm. CONCLUSIONS: The morphologic characteristics of the caries-affected dentin/interface suggest an increase in the exposed collagen zone and a decrease in the quality of the adhesive infiltration when compared with noncarious dentin. The evidence suggests that dentin substrate characteristics have a significant effect on the dentin/adhesive interface structure.

Benzoates↗

PubMedDate not supplied

Marginal adaptation of Cerec 3 CAD/CAM composite crowns using two different finish line preparation designs.

PURPOSE: The purpose of this study was to compare marginal discrepancies of Cerec 3 CAD/CAM composite crowns, fabricated on human prepared teeth with two different finish line designs, chamfer and shoulder. MATERIALS AND METHODS: Sixteen human molar teeth were used to prepare full crowns. Eight teeth were prepared with a 1-mm-wide chamfer finish line and the other eight with a 1.2- to 1.5-mm circumferential shoulder. Cerec 3 crowns were fabricated from optical impressions using Paradigm MZ100 composite polymer. Marginal adaptation was evaluated in two ways: (1) using modified United States Public Health Service (USPHS) criteria to evaluate eight preselected sites on each crown margin, and (2) using scanning electron microscopy (SEM) to measure marginal gaps on all four axial walls with 15 measurements on each wall (60 measurements per crown). An evaluation of the number of acceptable crowns, determined by having all measured sites per tooth with margin gap size less than 100 microm, as a function of finish line design was also conducted. RESULTS: In both chamfer and shoulder groups, there were only two crowns (out of eight) with clinically acceptable ratings for all eight measurement sites according to USPHS criteria. Fisher's chi-square analysis showed that there was no statistically significant difference in marginal adaptability as a function of finish line design ( p>0.05). With SEM imaging, overall mean marginal gaps for the chamfer group were 65.9+/-38.7 microm (range 35.0 to 130.0 microm), and for the shoulder group were 46.0+/-9.2 microm (range 26.3 to 55.6 microm); this difference was not found to be statistically significant ( p>0.05). While crown assessment based on mean marginal discrepancy measurements indicated that both the chamfer and shoulder groups were considered clinically acceptable (<100 microm); crown acceptability based on all measurement sites being less than 100 mum indicated that in the chamfer and shoulder groups there were four and three acceptable crowns out of eight, respectively. The Fisher's chi-square test indicated no statistically significant difference between the groups ( p>0.05). An agreement rate of 81.2% was calculated between the two evaluation methods, modified USPHS criteria and SEM measurements. CONCLUSIONS: Based on mean marginal discrepancy measurements, the typical marginal assessment technique, Cerec 3 Paradigm MZ100 crown restorations appear to have acceptable marginal adaptability (mean discrepancies <100 microm). Thus, the evidence from this investigation would suggest that the finish line preparation design had no effect on marginal adaptation for Cerec 3 composite crowns.

Ceramics↗

PubMedDate not supplied

Does babbling sound native? Listener responses to vocalizations produced by Swedish and American 12- and 18-month-olds.

Previous studies of infants' babbling have reported contradictory results as to the extent and timing of discernible phonetic influences of the ambient language. In the present experiment, five experienced phoneticians were asked to listen for ambient language effects on vocalizations produced by American and Swedish 12- and 18-month-olds (with 8 children in each language and age group), and to motivate their decisions in terms of word or phonetic cue perception. Group results indicated that listeners did not perceive effects of ambient language on pure babbles for either of the two age groups, whereas a clear effect appeared in both age groups given a more liberal definition of babbling. This is taken to suggest that results of ambient language listening tests may depend crucially on judgments of vocalizations' word status. As compared to the group trends, listener responses to individual children's vocalizations did not indicate that a majority of either 12- or 18-monthers were sufficiently native-sounding to be reliably identified on the basis of ambient language. A closer analysis of listeners' use of phonetic cues indicated that one single phonetic property, the grave tonal word accent, was discerned by most listeners in vocalizations produced by the Swedish 18-monthers; this property was also discerned by one listener in vocalizations produced by Swedish 12-monthers. This result is consistent with the generally held belief in the primacy of tonal features in phonetic acquisition, and with experimental evidence indicating that Swedish mothers tend to enhance word accent contours in baby talk. In the final section of the paper, the results are discussed with a view to reconcile competing theories of babbling development, notably the 'babbling drift' and the 'independence' hypotheses.

Child Development↗

PubMedDate not supplied

Reducing foley catheter device days in an intensive care unit: using the evidence to change practice.

The prolonged use of indwelling urinary catheters can lead to many complications, the most prevalent being urinary tract infections. These hospital-acquired infections can increase hospital costs, length of stay, and mortality rates. Evidence-based guidelines for the prevention of urinary tract infections are compared and discussed. Minimizing indwelling urinary catheter use is well-recognized in the literature to reduce the risk of these infections. To decrease the incidence of catheter-associated urinary tract infections, the staff of a 22-bed, mixed medical, surgical, and trauma intensive care unit focused on reducing the number of foley catheter device days. A multidisciplinary team was convened to create an evidence-based plan. Staff nurses were engaged in the development and implementation of the plan. Criteria-based foley catheter guidelines, a decision-making algorithm, and a daily checklist were implemented that led to a significant reduction in foley catheter device days and a decrease in catheter-associated urinary tract infections.

Algorithms↗

PubMedDate not supplied

Effect of measurement site on the dimensional accuracy of die-forming materials and techniques.

To date, the comparisons of dimensional accuracy of various die materials has been investigated primarily by using a one-dimensional measurement on one die. However, a single measurement may not adequately represent the complex preparations that are encountered frequently in clinical dentistry. This investigation utilized a standardized model with two identical dies to measure die accuracy at four sites, using five different die-forming materials/techniques.

Analysis of Variance↗

PubMedDate not supplied

Inter-examiner reliability of physical assessment methods for assessing temporomandibular disorders.

The purpose of this study was to evaluate whether non-expert examiners could reliably use the physical assessment methods described in the Research Diagnostic Criteria for temporomandibular disorders (RDC/TMD). Screening examinations were performed on patients with self-reported TMD symptoms by two examiners using techniques specified in Axis I of RDC/TMD diagnostic criteria. Both examinations and diagnostic categorization were carried out independently and blindly; reliability of the examiners was tested with appropriate parametric and non-parametric techniques. Assignment of diagnostic categories based on examination data showed levels of reliability ranging from acceptable to good. Concordance for diagnostic signs was good for determining opening click, closing click, and coarse crepitus, while concordance for determining protrusive click and joint space pain categories was poor. Using the examination and diagnosis procedures specified in the RDC/TMD, conscientious nonexpert examiners can assign diagnostic labels to the major subcategories of TMD with a satisfactory level of reliability.

Arthralgia↗

PubMedDate not supplied

Survey of general dentists regarding posterior restorations, selection criteria, and associated clinical problems.

This survey was designed to provide insight concerning the materials that general dentists use for direct and indirect posterior restorations. A stratified random sample of dentists (n = 2,880) from the Academy of General Dentistry's membership list received a questionnaire that elicited information on the clinician's current use of amalgam, direct, and indirect composite materials; reasons for material selection; and reported complications with composite restorations. Data were analyzed using descriptive statistics as well as t-test, Mann-Whitney, and chi square for group comparisons. A total of 714 dentists (26.3%) responded. Direct composite was the material used most commonly for posterior intracoronal restorations. Dentists in amalgam-free practices (31.6%) were significantly more likely (p = 0.001) to use direct composite than dentists whose practices used amalgam. Both groups weighed clinical decision factors and ranked perceived complications differently. Dentists in amalgam-free practices were less likely (p = 0.001) to consider caries rate, patient demand, and moisture control as important clinical decision factors and were more likely to report never experiencing complications.

Bicuspid↗