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Biomedical subjects

W F Vann

Publications and source records attributed to W F Vann.

107 records · Page 6Linked to original sources
PubMedDate not supplied

The K1 capsular polysaccharide of Escherichia coli.

Epidemiologic, immunologic, and genetic evidence indicate that the K1 capsular polysaccharide confers invasiveness to Escherichia coli. The capsule, an alpha-2----8-linked homopolymer of sialic acid (NeuNAc), provides the bacterium with a physical antiphagocytic barrier. Structural similarities between K1 and human tissue components suggest that immune tolerance may also be a factor in pathogenesis of K1 disease. The molecular and genetic events involved in the synthesis and export of the K1 polysaccharide were examined. The cloned K1 genes encode at least 12 proteins involved in capsule biosynthesis. These genes appear to be coordinately regulated and functionally clustered. One cluster is associated with the synthesis and activation of NeuNAc and includes the gene encoding CMP-NeuNAc synthetase. This enzyme catalyzes the activation of NeuNAc to CMP-NeuNAc. A second region, encoding five proteins, is associated with translocation of polysaccharide to the bacterial surface. The K1 polysaccharide is a poor immunogen in humans, and an understanding of the key reactions involved in K1 synthesis may help in providing an alternative to anticapsular immunity.

Animals↗
PubMedDate not supplied

Early childhood caries: analysis of psychosocial and biological factors in a high-risk population.

The influences that link social factors and caries development are not well understood, although mediation by stress has been suggested. The association between caregiver stress and early childhood caries (ECC), in particular, remains unclear. The purpose of this study was to examine the relationships between parenting stress and ECC while controlling for behavioral and biological factors in a high-risk population. One hundred and fifty healthy children aged 18-36 months were examined in a cross-sectional study design. Parental interviews were conducted to obtain demographic, oral health behavior and parenting stress data. Clinical data included parent and child bacterial measures, fingernail fluoride analyses, caries prevalence and presence of child enamel hypoplasia. Bivariate analyses revealed that parenting stress predicted caries. Multivariate analyses demonstrated that a combination of psychosocial, behavioral, temporal and biological variables predicted ECC outcomes. Total parenting stress did not contribute independently to the best prediction model. Our findings suggest the need for the development of a multidimensional stress model that considers the parent-child dyad to elucidate further the link between psychosocial factors and ECC.

Adult↗
PubMedDate not supplied

Children's utilization of dental care in the NC Medicaid program.

PURPOSE: To characterize the patterns of dental care in the North Carolina (NC) Medicaid Program for three- and eight-year-old children who began dental treatment in the 1985-86 and 1990-91 groups. We also compared the children's patterns of care by provider (general dentists versus pediatric dentists). METHODS: Our extensive data set included claims, enrollment, and provider data. Children were assigned to one of five categories or patterns of care as follows: complete care, general anesthesia care, sporadic care, emergency only care, and no care. Statistical comparisons of the variables age, cohort year, and provider groups were made. RESULTS: The use of Medicaid dental services by both age groups was severely limited in both yearly cohorts. Pediatric dentists tended to provide more complete and less sporadic care for both age groups and both yearly cohorts. CONCLUSIONS: Financing dental care through Medicaid results in very low levels of complete care among enrollees, and any plan that limits referral to pediatric dentists might adversely affect the number of enrollees who receive complete care.

Age Factors↗
PubMedDate not supplied

A cost analysis of treating pediatric dental patients using general anesthesia versus conscious sedation.

PURPOSE: The purpose of this pilot study is to report a cost comparison of general anesthesia (GA) versus oral conscious sedation (CS) for the treatment of pediatric dental patients. METHODS: The study sample included 22 children whose parents/guardian selected GA care for their child. Selection criteria limited inclusion to healthy children (ASA I) ages 24-60 m.o. The subjects acted as their own comparison group to an estimation CS model. Models were developed to assess societal costs for treatment under GA and CS. Treatment rendered was equalized using the dental Relative Based Value Units Scale (RBVU). RESULTS: Ordinary Least Squares Regression analysis techniques showed the association of RBVU to the total societal costs of GA and CS to be significant (P < 0.01) with an adjusted R2 of .64 and .78 respectively. When regression lines were plotted, the intersection represented RBVU level at which societal costs of GA and CS were the same. CONCLUSION: Under the conditions of this pilot study, it is concluded that CS costs exceed GA costs at a RBVU level of 66.4, which would equate to more than three CS appointments.

Anesthesia, Dental↗
PubMedDate not supplied

The physiological effects of supplemental oxygen versus nitrous oxide/oxygen during conscious sedation of pediatric dental patients.

PURPOSE: This study was performed to compare the effects of nitrous oxide/oxygen (N2O/O2) versus oxygen (O2) as adjuncts to an oral narcotic regimen for pediatric conscious sedation. METHODS: Using a randomized double-blind crossover design, 19 children (mean age 41 +/- 8.6 months) were sedated with chloral hydrate (50 mg/kg), meperidine (1.5 mg/kg) and hydroxyzine pamoate (25 mg) for two appointments. Patients were assigned randomly to receive 100% O2 at one visit and 50% N2O/O2 at the other. Physiologic parameters were measured in five-minute intervals, including respiratory rate, pulse rate (PR), oxyhemoglobin saturation (SpO2) and end-tidal carbon dioxide. Data analyses focused on true desaturations and apnea, level of sedation and sedation outcomes. RESULTS: There were no differences in PR, SpO2 and risk of desaturation between the inhalation agents. The level of sedation was deeper and the sedation outcomes were better in the N2O/O2 group. CONCLUSION: N2O/O2 deepened the sedation while improving its success with minimal alteration in physiologic parameters.

Anesthesia, Dental↗
PubMedDate not supplied

Conscious sedation of pediatric dental patients: an investigation of chloral hydrate, hydroxyzine pamoate, and meperidine vs. chloral hydrate and hydroxyzine pamoate.

This study evaluated two oral sedative regimens for the conscious sedation of pediatric dental patients (mean age 37.0 months) unmanageable by traditional behavior management techniques. Regimen A included chloral hydrate (Noctec--E.R. Squibb and Sons, Princeton, NJ) at 50 mg/kg with 25 mg hydroxyzine pamoate (Vistaril--Pfizer Laboratories, New York, NY), plus meperidine (Demerol--Winthrop-Breon, New York, NY) at 1.5 mg/kg. Regimen B included chloral hydrate at 50 mg/kg with 25 mg hydroxyzine pamoate. In a crossover research design, 10 patients were assigned randomly to receive one regimen, to be followed by the alternative regimen during the second appointment. The primary purpose of this study was to determine if meperidine would improve patient behavior, and increase the prevalence of respiratory compromise. A secondary purpose of the study was to develop an objective method to assess behavior during the conscious sedation of pediatric dental patients. Results revealed that the addition of oral meperidine to chloral hydrate and hydroxyzine pamoate resulted in improved behavior (P less than 0.01) during local anesthetic injection, rubber dam delivery, and the operative dental procedure. There was no increase in the prevalence of respiratory compromise with the addition of meperidine.

Anesthesia, Dental↗
PubMedDate not supplied

Time required for placement of composite versus amalgam restorations.

This study was designed to develop an indirect method for measuring the time required for restoration placement; and to compare the operator time required for placement of amalgam and composite resins in posterior teeth in children. Forty children, aged seven to nine years old, were selected to participate. Either amalgam or an experimental resin was used to restore the primary and permanent molars. All restorations and sealants were completed under the rubber dam. Each restorative appointment was videotaped with a color video camera mounted on the ceiling. Ninety-six restorative procedures were reviewed and evaluated for the amount of time necessary to accomplish them. The Class I permanent molar composite restoration required 35 percent more insertion and finishing time than did the amalgam.

Bicuspid↗
PubMedDate not supplied

Distribution of primary tooth caries in first-grade children from two nonfluoridated US communities.

In a prospective longitudinal study, 1099 first grade children from Aiken, South Carolina, and 1086 children from Portland, Maine, were examined annually for 3 years. Caries prevalence and dmfs incidence were determined. The mean dmfs in Portland children was 2.9. In Aiken, white children had a mean dmfs of 8.4, and black children had a mean dmfs of 10.2. The mean 3-year primary tooth caries increment was 1.5 surfaces in the Portland cohort 3.3 surfaces in the Aiken white cohort and 2.8 surfaces in the Aiken black cohort. These increments were divided evenly between interproximal and fissure surfaces. Twenty percent of the children in Portland had 75% of the caries; in Aiken, 20% of the children had 60% of the caries. This distribution suggests a high-risk group that could be targeted for aggressive caries prevention efforts if risk factors can be identified.

Child↗
PubMedDate not supplied

Pediatric dentists' participation in the North Carolina Medicaid program.

Data on Medicaid participation by dentists in North Carolina were obtained from the North Carolina Division of Medical Assistance and through a survey of pediatric dentists. As a group, pediatric dentists were the most active participants in the North Carolina Medicaid program during the 1990-91 state fiscal year and provided a disproportionate share of treatment for Medicaid-eligible children. Seventy-five per cent of the pediatric dentists limit their Medicaid participation. Top reasons given for limiting access for new Medicaid patients included low reimbursement rates, broken or canceled appointments, and need for prior authorization of Medicaid treatment plans. This paper explores several critical issues regarding access to dental care for children served by the Medicaid program in North Carolina.

Chi-Square Distribution↗
PubMedDate not supplied

A comparison of conventional versus electronic monitoring of sedated pediatric dental patients.

The first purpose of this study was to compare traditional monitoring methods to electronic instruments for monitoring physiologic parameters during conscious sedation of pediatric dental patients. Traditional methods included careful visual assessment of skin color, airway patency and chest movements, and auscultation of breath and heart sounds using a precordial stethoscope; electronic instruments included the capnograph and pulse oximeter. The second purpose of the study was to examine the potential of the capnograph to provide more advanced warning than the pulse oximeter for respiratory compromise. Thirty-nine children (mean age 39 months) received an oral sedative regimen of chloral hydrate, hydroxyzine pamoate, and meperidine and all were supplemented with 100% oxygen via nasal cannula throughout their sedations. One investigator used traditional monitoring and the other used electronic--both monitored simultaneously while being shielded (blinded) from each other. Electronic monitoring yielded a false alert rate of 88% compared with 73% for traditional monitoring. Ten confirmed episodes of respiratory compromise were identified electronically and only three were identified by traditional monitoring. All of the 10 confirmed respiratory compromise episodes were detected by capnography; none were detected by oximetry. During these 39 pediatric sedations using a narcotic drug regimen and 100% oxygen supplementation, there were no true desaturations.

Anesthesia, Dental↗
PubMedDate not supplied

Pediatric and general dentists' participation in the North Carolina Medicaid program: trends from 1986 to 1992.

The purpose of this study was to report trends in dentists' participation in the North Carolina Medicaid program. Medicaid claims files for dental users younger than age 21 were analyzed for seven fiscal years (FY) from 1986 to 1992. Over the study period, the number of pediatric dentists filing any Medicaid claims remained constant but the number of participating general dentists decreased slightly. Intensity of participation, as measured by mean annual reimbursement and mean number of children treated per dentist, increased from FY 89 to 92 for both provider groups. The mean value of services provided for each dental users also increased slightly during the same period. The data revealed over time pediatric dentists treated a larger proportion of the youngest Medicaid dental users.

Child↗
PubMedDate not supplied

The effect of supplemental oxygen on apnea and oxygen saturation during pediatric conscious sedation.

PURPOSE: This study compared the effect of supplemental oxygen (O2) on pediatric patients' apnea status and oxyhemoglobin saturation during: 1) conscious sedation for dental procedures and 2) the recovery period following sedation. METHODS: Fourteen child patients (mean age 42 months) sedated with 50 mg/Kg chloral hydrate, 25 mg hydroxyzine pamoate, and 1.5 mg/Kg meperidine were treated for two separate appointments. The patients received supplemental O2 via nasal cannulae at random at one of the two appointments. Following the operative period, all patients were monitored sitting upright for an additional 15 min. RESULTS: Intraoperative results showed that the risk of apnea was 39% (11/28), with apneic events distributed equally between O2 and non-O2 supplemented sedations. The overall risk of desaturation was 29% (8/28). Mean SpO2 was always elevated with O2 supplementation and the mean difference in O2 versus non-O2 was statistically significant. The risk of apnea in the postoperative period was 7% (1/14) for both the non-O2 and O2-supplemented patients. The risk of desaturation in the postoperative period was 11% (3/28) with one desaturation in a non-O2 and two desaturations in O2-supplemented patients. CONCLUSION: We conclude that intraoperative O2 supplementation prevents desaturations even in the presence of apnea during pediatric conscious sedation.

Adjuvants, Anesthesia↗