PubMed Health⌕ Search

Biomedical subjects

J J Warren

Publications and source records attributed to J J Warren.

At least 19 recordsLinked to original sources
PubMed2005

Primary tooth fluorosis in 5-year-old schoolchildren in Ireland.

AIM: This was to determine the prevalence of primary tooth fluorosis in the dentitions of 5-year-old schoolchildren. A subsidiary aim was to investigate whether an association existed between the presence of primary tooth fluorosis, fluoridation status, infant feeding practices or the oral hygiene practices of the child. STUDY DESIGN: A cross-sectional and stratified by fluoridation status study. METHODS: Fluorosis was recorded using a modification of the Tooth Surface Index of Fluorosis (TSIF). Demographic data, information on infant feeding practices and oral hygiene practices were collected via a parental questionnaire. STATISTICS: Stepwise logistic regression analysis. RESULTS: Fluorosis prevalence in the fluoridated group (n=208) was 32%; 29.3% (n=61) had a modified TSIF score of 1; 2.4% (n=5) had a modified TSIF score of 2; and 1% (n=1) had a modified TSIF score of 5. In the non-fluoridated group (n=86) one child had a modified TSIF score of 1. Primary tooth prevalence of fluorosis in the entire sample (n=294) was 23%. Factors that were associated with primary tooth fluorosis were: fluoridation status (p= 0.0003, 95% CI = 5-281) and the age at which toothbrushing with toothpaste commenced (p = 0.016, 95% C.I. 1.1 - 3.8). No association with infant feeding practices was identified. CONCLUSION: The overall prevalence of primary tooth fluorosis was 23%. Lifetime residence in a fluoridated area and commencement of toothbrushing with toothpaste between 12 and 18 months of age were associated with primary tooth fluorosis. No association with infant feeding practices was identified.

Bottle Feeding↗
PubMed2004

The timing of subsequent treatment for teeth restored with large amalgams and crowns: factors related to the need for subsequent treatment.

Crowns and large amalgams protect structurally compromised teeth to various degrees in different situations. The aim of this investigation was to evaluate the survival of teeth with these two types of restorations and the factors associated with better outcomes. Retrospective administrative and chart data were used. Survival was defined and modeled as: (1) receipt of no treatment and (2) receipt of no catastrophic treatment over five- and 10-year periods. Analyses included: Kaplan-Meier survival curves, Log-Rank tests, and Cox proportional hazards regression modeling. Crowns survived longer with no treatment and with no catastrophic treatment; however, mandibular large amalgams were least likely to have survived with no treatment, and maxillary large amalgams were least likely to have survived with no catastrophic treatment. Having no adjacent teeth also decreased survival. Crowns survived longer than large amalgams, but factors such as arch type and the presence of adjacent teeth contributed to the survival of large amalgams.

Bicuspid↗
PubMed2002

An evaluation of the usefulness of two terminology models for integrating nursing diagnosis concepts into SNOMED Clinical Terms.

OBJECTIVES: We evaluated the usefulness of two models for integrating nursing diagnosis concepts into SNOMED Clinical Terms (CT). METHODS: First, we dissected nursing diagnosis term phrases from two source terminologies (North American Nursing Diagnosis Association Taxonomy 1 (NANDA) and Omaha System) into the semantic categories of the European Committee for Standardization (CEN) categorical structure and ISO reference terminology model (RTM). Second, we critically analyzed the similarities between the semantic links in the CEN and ISO models and the semantic links used to formally define diagnostic concepts in SNOMED CT. RESULTS: Our findings demonstrated that focus, bearer/subject of information, and judgment were present in 100% of the NANDA and Omaha term phrases. The Omaha term phrases contained no additional descriptors beyond those considered mandatory in the CEN and ISO models. The comparison among the semantic links showed that SNOMED CT currently contains all but one of the semantic links needed to model the two source terminologies for integration. In conclusion, our findings support the potential utility of the CEN and ISO models for integrating nursing diagnostic concepts into SNOMED CT.

Classification↗
PubMed2001

A maximum likelihood method for determining D(a)(PQ) and R for sets of dipolar coupling data.

The algorithms available today that use dipolar coupling data for macromolecular structure determination require the independent determination of two parameters, D(a)(PQ) and R. Methods exist for obtaining these parameters when the set of dipolar couplings available is large and the orientations of the interatomic vectors on which they report is isotropically distributed. These methods are less satisfactory when the set is small and anisotropic. Described here is a maximum likelihood method that extracts accurate values for D(a)(PQ) and R from small, anisotropic data sets. Also demonstrated is a procedure for estimating the errors associated with the values of D(a)(PQ) and R obtained and for incorporating these errors into refinement protocols.

Algorithms↗
PubMed2001

Application of dipolar coupling data to the refinement of the solution structure of the sarcin-ricin loop RNA.

Residual dipolar couplings can provide the long-range information that most NMR solution structures lack. The use of such data in protein structure determinations is now fairly routine, but even though these data should be much more useful for nucleic acids, their application to nucleic acid structure determination is still in its infancy. Here we present a method for producing accurate, dipolar-refined structures of nucleic acids that is more efficient than those used previously, and apply it to E73, a 29 nucleotide RNA that includes the sarcin-ricin loop from rat 28S rRNA. The results enable us to address the differences between the crystal structure of E73 and the solution structure proposed for it previously.

Animals↗
PubMed2001

Evaluation of nonrinse conditioning solution and a compomer as an alternative method of bonding orthodontic bracket.

Damage to the enamel surface during bonding and debonding of orthodontic brackets is a clinical concern. Alternative bonding methods that minimize enamel surface damage while maintaining a clinically useful bond strength are an aim of current research. The purpose of this study was to compare the effects of using two enamel conditioners and adhesives on the shear bond strength and bracket failure location. Forty freshly extracted human molars were pumiced and randomly divided into two groups of 20 teeth. Metal orthodontic brackets were bonded to the enamel surface by one of two protocols: 37% phosphoric acid with a composite adhesive (Transbond XT) or a nonrinse conditioner with a compomer adhesive (Dyract flow). The teeth were mounted in phenolic rings and stored in deionized water at 37 degrees C for 24 hours. A Zwick Universal Testing Machine was used to determine shear bond strengths in MegaPascals. The residual adhesive on the enamel surface was evaluated using the Adhesive Remnant Index. Student t-test and chi2-test were used to compare the two groups. Significance was predetermined at P < or = .05. The results of the t-tests indicated that there were significant differences between the two adhesive systems (t = 11.18 and P = .001) with the nonrinse conditioner/compomer system having lower shear bond strength (X = 1.7 +/- 0.9 MPa) than the phosphoric acid/composite adhesive (X = 10.4 +/- 2.8 MPa). The results of the Chi Square test evaluating the residual adhesives on the enamel surfaces also revealed significant differences between the two groups (chi2 = 7.62, P = .022). In conclusion, a nonrinse conditioner used with a compomer adhesive had significantly lower shear bond strength than a phosphoric acid/composite adhesive system.

Acid Etching, Dental↗
PubMed2001

Effect of using a new cyanoacrylate adhesive on the shear bond strength of orthodontic brackets.

During bonding of orthodontic brackets to enamel, conventional adhesive systems use three different agents: an enamel conditioner, a primer solution, and an adhesive resin. A unique characteristic of some new bonding systems is that they need neither a priming agent nor a curing light to bond brackets. Such an approach should be more cost-effective for the clinician and indirectly also for the patient. The purpose of this study was to determine the effects of using a cyanoacrylate adhesive on the shear bond strength of orthodontic brackets and on the bracket/adhesive failure mode. The brackets were bonded to extracted human teeth according to one of two protocols. Group 1: Teeth were etched with 37% phosphoric acid. After applying the primer, the brackets were bonded with Transbond XT (3M Unitek, Monrovia, Calif) and were light-cured for 20 seconds. Group 2: Teeth were etched with 35% phosphoric acid. The brackets were then bonded with Smartbond (Gestenco International, Göthenburg, Sweden). The present in vitro findings indicated that the use of the cyanoacrylate adhesive to bond orthodontic brackets to the enamel surface did not result in a significantly different (P = .24) shear bond force (mean = 5.8 +/- 2.4 MPa) as compared to the control group (mean = 5.2 +/- 2.9 MPa). The comparison of the Adhesive Remnant Index scores indicated that there was significantly (P = .006) less residual adhesive remaining on the tooth with the cyanoacrylate than on the tooth with the conventional adhesive system. In conclusion, the new adhesive has the potential to be used to bond orthodontic brackets while reducing the total bonding time.

Acid Etching, Dental↗
PubMed2001

A prospective study of antibiotic use and associated infections in young children.

This study examines antibiotic usage and associated infections in infants and young children in Iowa. Longitudinal data were collected using a cohort recruited at birth from eight hospitals in eastern Iowa. Parents of recruited children were mailed questionnaires at 6 weeks, and 3, 6, 9, 12, 16, and 20 months of age. The cumulative incidence of antibiotic use and associated infections was determined using Kaplan-Meier survival analysis. There were data on 1,368 children. Antibiotic use was common in our cohort and increased with age. Beginning at age 3 months, approximately 50% of the cohort was exposed to an antibiotic during each reporting period. Otitis media was the most common indication and was responsible for 67.3% of antibiotic use. Children were most frequently treated with amoxicillin, followed by the cephalosporins and sulphonamides. By 12 and 20 months of age 79.0% and 92.5% of the children, respectively, had been treated with at least one course of antibiotics. Children received antibiotics for a median of 43 days by 20 months of age. Males were more likely to experience any antibiotic exposure than females (hazard ratio = 1.18) and showed a trend for more days of use (P = 0.052). There was a small but significant variation in antibiotic usage in the different recruitment communities (P = 0.02).

Anti-Bacterial Agents↗
PubMed2001

Comparison of dental arch measurements in the primary dentition between contemporary and historic samples.

The purpose of this study was to investigate secular changes that may have occurred in dental arch dimensions by comparing a sample of contemporary North American white children (born between 1992 and 1995) in the primary dentition to those children found in an earlier study of North American white children (born between 1946 and 1948). The sample of contemporary children has been followed prospectively since birth and was assessed at 4(1/2) to 5 years of age. Data for the historic sample were obtained from 5-year-old children who were enrolled in the Iowa Growth Study. The 2 samples were similar in terms of geographic location, racial and ethnic backgrounds, and socioeconomic status. To further enhance the comparison and to match the 2 groups, the 2 samples were restricted to white children with a normal overjet (<4 mm) and normal anteroposterior molar relationship, no anterior open bite, and no crossbite. In addition, individuals were excluded if any permanent teeth were erupted. Measurements of maxillary and mandibular arch lengths and intercanine and intermolar arch widths were made, with measurements of overjet and overbite. The results indicated that maxillary and mandibular arch lengths in both sexes were significantly shorter in the contemporary sample; all arch widths were significantly smaller in contemporary boys, but not in girls. These findings suggest that average arch dimensions may be smaller in contemporary children than in past generations. Further research is needed to determine whether smaller arch dimensions are associated with more crowding in the primary, mixed, and permanent dentitions.

Case-Control Studies↗
PubMed2001

Effect of a self-etch primer/adhesive on the shear bond strength of orthodontic brackets.

Conventional adhesive systems use 3 different agents (an enamel conditioner, a primer solution, and an adhesive resin) during the bonding of orthodontic brackets to enamel. A unique characteristic of some new bonding systems in operative dentistry is that they combine the conditioning and priming agents into a single product. Combining conditioning and priming saves time and should be more cost-effective to the clinician and, indirectly, to the patient. The purpose of this study was to determine the effects of the use of a self-etch primer on the shear bond strength of orthodontic brackets and on the bracket/adhesive failure mode. Brackets were bonded to extracted human teeth according to 1 of 2 protocols. In the control group, teeth were etched with 37% phosphoric acid. After the sealant was applied, the brackets were bonded with Transbond XT (3M Unitek, Monrovia, Calif) and light cured for 20 seconds. In the experimental group, a self-etch acidic primer (ESPE Dental AG, Seefeld, Germany) was placed on the enamel for 15 seconds and gently evaporated with air, as suggested by the manufacturer. The brackets were then bonded with Transbond XT as in the first group. The present in vitro findings indicate that the use of a self-etch primer to bond orthodontic brackets to the enamel surface resulted in a significantly (P = .004) lower, but clinically acceptable, shear bond force (mean, 7.1 +/- 4.4 MPa) as compared with the control group (mean, 10.4 +/- 2.8 MPa). The comparison of the adhesive remnant index scores indicated that there was significantly (P = .006) more residual adhesive remaining on the teeth that were treated with the new self-etch primer than on those teeth that were bonded with the use of the conventional adhesive system.

Acid Etching, Dental↗
PubMed2001

Inadequate nutrient intakes are common and are associated with low diet variety in rural, community-dwelling elderly.

Poor dietary habits and inadequate nutrient intakes are of concern in the elderly. The nutritional characteristics of those who survive to become the oldest are not well defined. Our goal was to describe dietary habits, nutrient intakes and nutritional risk of community-dwelling, rural Iowans, 79 y of age and older. Subjects were interviewed (n = 420) using a standardized format on one occasion in their homes and instructed to complete 3-d diet records (n = 261) after the in-home interview. Standardized interviews assessed demographic information, cognitive function and dietary habits (Nutrition Screening Initiative Checklist). Adequate nutrient intake was defined as consumption of the nutrient's estimated average requirement, 67% adequate intake or 67% recommended dietary allowance. Mean age was 85.2 y, 57% lived alone and 58% were widowed. Subjects completing 3-d diet records were younger, more cognitively intact and less likely to be at nutritional risk than subjects not completing diet records. The percentage of subjects with inadequate intakes of selected nutrients was 75% for folate, 83% for vitamin D and 63% for calcium. Eighty percent of subjects reported inadequate intakes of four or more nutrients. Diet variety was positively associated with the number of nutrients consumed at adequate intakes (r = 0.498), total energy (r = 0.522) and dietary fiber (r = 0.421). Our results suggest that rural, community-dwelling old have inadequate intakes of several nutrients. Recommendations to increase diet variety and consume a nutrient supplement may be necessary for elderly people to achieve adequate nutrient intakes.

Aged↗
PubMed2001

Patterns of fluoride intake from birth to 36 months.

OBJECTIVES: Dental fluorosis prevalence has increased in the United States, Canada, and other nations due to the widespread availability of fluoride in many forms, with fluoride ingestion during the first three years of life appearing most critical in fluorosis etiology. With few contemporary studies of fluoride ingestion in this age group, the purpose of this paper is to describe patterns of estimated fluoride ingestion from birth to 36 months of age from water, dentifrice, and dietary fluoride supplements and combined. METHODS: Repeated responses to separate series of questions about water intake, use of fluoride dentifrice, and use of fluoride supplements were collected by questionnaire as part of the longitudinal Iowa Fluoride Study and used to estimate fluoride intake. Estimated intake is reported by source and combined at different ages. Effects of subject age and other covariates on fluoride intake were assessed using regression methods appropriate for the analysis of correlated data. RESULTS: For most children, water fluoride intake was the predominant source, especially through age 12 months. Combined daily fluoride intake increased through 9 months, was lower at 12 and 16 months, and increased again thereafter. Mean intake per unit body weight (bw) was about 0.075 mg F/kg bw through 3 months of age, 0.06 mg F/kg bw at 6 and 9 months, 0.035 mg F/kg bw at 12 and 16 months, and 0.043 mg F/kg bw from 20-36 months. Depending on the threshold chosen (e.g., 0.05 or 0.07 mg F/kg bw), variable percentages of the children exceeded the levels, with percentages greatest during the first 9 months. Regression analyses showed fluoride intake (mg F/kg bw) from 1.5-9 months to decrease with increasing child's age, mother's age, and mother's education, with a complex three-way interaction among these factors. From 12-20 months, fluoride intake increased with increasing child age and decreased with increasing mother's age. No statistically significant relationships were found for fluoride intake from 24-36 months. CONCLUSIONS: There is considerable variation in fluoride intake across ages and among individuals. Longitudinal studies may be necessary to fully understand the relationships between fluoride ingestion over time and development of fluorosis.

Adult↗
PubMed2001

Prevalence of dental fluorosis in the primary dentition.

OBJECTIVES: This paper presents data on the prevalence of primary tooth fluorosis among children residing in Iowa, and the relationships between fluorosis prevalence and selected measures of fluoride exposures. METHODS: Children in the study cohort were followed prospectively during the first year of life. This study assessed their home water fluoride concentrations and use of fluoride dentifrice or dietary fluoride supplements. A total of 637 children (320 females and 317 males) were examined for fluorosis using a modification of the TSIF index at age 4 1/2 to 5 years, with 90.4 percent having intact primary dentitions. RESULTS: 74 children (11.6%) had fluorosis present on one or more of their primary teeth, and 71 children (11.1%) had two or more teeth affected. Nearly all fluorosis was mild, with the primary second molar teeth most commonly affected. Fluorosis was significantly associated with higher water fluoride concentration, but not with the use of dentifrice or fluoride supplements. CONCLUSIONS: The results of this study show that primary tooth fluorosis is relatively uncommon, but is most frequently seen on the posterior teeth, particularly the primary second molars, which form at later stages of development. This finding suggests that primary tooth fluorosis is mostly a postnatal phenomenon, and is associated with higher water fluoride levels.

Cariostatic Agents↗
PubMed2001

Effects of oral habits' duration on dental characteristics in the primary dentition.

BACKGROUND: Studies dating to the 1870s have demonstrated that long-term nonnutritive sucking habits may lead to occlusal abnormalities, including open bite and posterior crossbite. However, little is known as to whether habits of shorter durations have lasting effects. METHODS: The authors collected longitudinal data on nonnutritive sucking among children through a series of questionnaires regularly completed by parents. Researchers examined the children at ages 4 to 5 years and obtained study models. The models were measured for dental arch parameters (including arch width, arch length and arch depth) and assessed for overjet, overbite and posterior crossbite. The authors compared the dental arch and occlusal conditions among groups of children with nonnutritive sucking habits of different durations. RESULTS: Children with nonnutritive sucking habits that continued to 48 months of age or beyond demonstrated many significant differences from children with habits of shorter durations: narrower maxillary arch widths, greater overjet and greater prevalence of open bite and posterior crossbite. In addition, compared with those who ceased their habit by 12 months of age, those with habits at 36 months of age had significantly greater mandibular canine arch widths, maxillary canine arch depths and overjet, while those with habits at 24 months and 36 months had significantly smaller palatal depths. Prevalence of anterior open bite, posterior crossbite and excessive overjet (> 4 millimeters) increased with duration of habits. CONCLUSIONS: While continuous nonnutritive sucking habits of 48 months or longer produced the greatest changes in dental arch and occlusal characteristics, children with shorter sucking durations also had detectable differences from those with minimal habit durations. CLINICAL IMPLICATIONS: It may be prudent to revisit suggestions that sucking habits continued to as late as 5 to 8 years of age are of little concern.

Analysis of Variance↗
PubMed2001

Physical activity and bone measures in young children: the Iowa bone development study.

OBJECTIVES: Physical activity has a beneficial effect on bone development in circumpubertal children, although its effect on younger children is uncertain. In this cross-sectional study, we examined associations between physical activity and bone measures in 368 preschool children (mean age: 5.2 years, range: 4-6 years). DESIGN: Physical activity was measured using 4-day accelerometry readings, parental report of children's usual physical activity, and parental report of children's hours of daily television viewing. Total body and site-specific bone mineral content and area bone mineral density (BMD) were measured by dual energy radiograph absorptiometry. RESULTS: After adjustment for age and body size, accelerometry measures of physical activity and parental report of usual physical activity were consistently and positively associated with bone mineral content and BMD in both boys and girls (r = 0.15-0.28). Television viewing was inversely associated with hip BMD in girls (r = -0.15). The proportion of variance in bone measures explained by physical activity in linear regression models ranged from r(2) = 1.5% to 9.0%. In all of these models except total body BMD, at least 1 and often several of the physical activity variables entered as independent predictors. Activity variables most likely to enter the regression models were vigorous physical activity (as determined by accelerometry) and parental ranking of child's usual physical activity. CONCLUSIONS: Findings indicate that there are statistically significant and, perhaps important, associations between physical activity and bone measures during early childhood, well ahead of the onset of peak bone mass. This would suggest that intervention strategies to increase physical activity in young children could contribute to optimal bone development.

Absorptiometry, Photon↗
PubMed2000

Infant oral health and oral habits.

Many oral diseases and conditions, including dental caries (cavities) and malocclusions, have their origins early in life. Prudent anticipatory guidance by the medical and dental professions can help prevent many of the more common oral health problems. This article provides information on the rationale for early dental examination and instructions for pediatric and family practitioners in scheduling and conducting an early oral intervention appointment. In addition, feeding practices, non-nutritive sucking, mouth breathing, and bruxing are discussed, including their effects on orofacial growth and development.

Dental Care for Children↗
PubMed2000

Comparison of three salivary flow rate assessment methods in an elderly population.

Measuring salivary flow rates among the frail elderly is a challenge. The currently used spit collection method requires levels of time and cooperation that often may exclude the frail elderly who are at high risk for salivary compromise. A measurement method that is not only valid and reliable, but also feasible and acceptable is needed for use in population studies of compromised adults. This study compared two salivary flow rate assessment methods using a suction machine against the currently accepted spit collection method in an elderly population aged 75 and older. Three methods of flow rate (g/min) assessment were compared at three time periods among 16 elders (mean age 86.6 years). Flow rates using the 2-min open suction method compared well with the 10-min spit method (r=0.778) but the 2-min closed suction method did not (r=0.158). Reliability evaluation of the open suction method and the spit method was assessed using a test/retest with a 1-week interval. Both methods demonstrated good comparable reliability (spit method r=0.566, P=0.01); open suction method, (r= 0.861, P<0.01). Based on a short survey questionnaire about the three methods, 11 of the 16 elderly subjects preferred the use of the suction machine to the spit method. These results indicate that the 2-min open suction method technique is a valid and reliable means of measuring salivary flow. The lower level of patient cooperation needed, the shorter time period required, and this preliminary report of its acceptability support the use of this method in future population studies of frail elders.

Aged↗