Deborah V Dawson

University of Iowa, Iowa City, Iowa, United States

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Publications (153)173.07 Total impact

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    ABSTRACT: Background: Recent studies point to the clinical utility of using peri-implant sulcular fluid (PISF) as a valuable diagnostic aid for monitoring peri-implant tissue health. The objectives of this study were to determine the levels of key biomarkers in PISF in periodontal maintenance participants and compare them to their corresponding levels in gingival crevicular fluid (GCF) obtained from the same participants. Methods: PISF and GCF were collected from an implant and a contralateral natural tooth, after the clinical examination of 73 participants. The levels of interleukin (IL)-1α, IL-1β, IL-6, IL-8, IL-10, IL-12, IL-17A, tumor necrosis factor (TNF)-α, C-reactive protein (CRP), osteoprotegerin (OPG), leptin, and adiponectin were determined using multiplex proteomic immunoassays. The correlation of biomarker concentrations between GCF versus PISF, within GCF or PISF, and with several covariates (age, brushing frequency, days since professional cleaning, probing depth and plaque index) were also determined. Results: Significantly higher levels of IL-17A (p=0.02) and TNF-α (p=0.03) were noted in PISF, when compared to their levels in GCF. Significant positive correlations were noted between the concentrations of cytokines in PISF versus their levels in GCF. Among the covariates, significant positive correlation was noted between mean probing depths around implants and levels of IL-1β (p<0.05) and IL-8 levels (p<0.05) in PISF. Conclusions: The results of this study point to the differential expression of specific biomarkers in GCF versus their levels in PISF in periodontal maintenance patients, which is critical information prior to establishing PISF as a diagnostic fluid to monitor peri-implant health.
    Journal of periodontology. 09/2014;
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    ABSTRACT: Objectives: The purpose of this study was to demonstrate the effectiveness of the stepwise excavation procedure (SWP) for the treatment of deep carious lesions performed at The University of Iowa College of Dentistry (UICD) between 2004-2012 in patients from 18 to 65 years of age. Methods: A retrospective analysis was done using recorded data of patients who had SWP in any of their teeth between 2004-2012 using the Electronic Health Record- Axium at the UICD. The primary outcome denoting successful treatment was tooth survival, defined as a SWP treated tooth which was re-evaluated/re-entered, did not result in an outcome of root canal treatment or extraction, and for which a final direct/indirect restorative material was placed. Restorative outcomes were assessed after the re-evaluation/re-entry of vital teeth treated by SWP. Descriptive statistics were generated, to estimate the proportions of successful outcomes. The association between treatment outcomes and factors such as age, gender, provider, number of miles traveled to the UICD, size of restoration, tooth arch position, and tooth type were also evaluated. Results: Our preliminary data showed that the number of SWP performed at the UICD between 2004-2012 was 1985 (1326 subjects). Within the 18 months interval after the SWP was performed, the number of teeth re-evaluated/re-entered was 767 (38.6%), and 1218 (61.4%) were not re-entered/re-evaluated. Of the re-evaluated procedures 599 had a final direct/indirect restorative material placed (~78%). Additional analyses evaluated the association of clinical outcomes and survival rates of stepwise excavation completed treatments with demographic characteristics and tooth characteristics. Conclusions: These preliminary results provide significant information regarding the outcomes of SWPs completed at the UICD from 2004 to 2012. Additional investigation is needed to determine the reasons for the high percentage of procedures with no re-evaluation/re-entry follow-up.
    IADR General Session and Exhibition 2014; 06/2014
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    ABSTRACT: Alveolar ridge preservation strategies are indicated to minimize the loss of ridge volume that typically follows tooth extraction. The aim of this systematic review was to determine the effect that socket filling with a bone grafting material has on the prevention of postextraction alveolar ridge volume loss as compared with tooth extraction alone in nonmolar teeth. Five electronic databases were searched to identify randomized clinical trials that fulfilled the eligibility criteria. Literature screening and article selection were conducted by 3 independent reviewers, while data extraction was performed by 2 independent reviewers. Outcome measures were mean horizontal ridge changes (buccolingual) and vertical ridge changes (midbuccal, midlingual, mesial, and distal). The influence of several variables of interest (i.e., flap elevation, membrane usage, and type of bone substitute employed) on the outcomes of ridge preservation therapy was explored via subgroup analyses. We found that alveolar ridge preservation is effective in limiting physiologic ridge reduction as compared with tooth extraction alone. The clinical magnitude of the effect was 1.89 mm (95% confidence interval [CI]: 1.41, 2.36; p < .001) in terms of buccolingual width, 2.07 mm (95% CI: 1.03, 3.12; p < .001) for midbuccal height, 1.18 mm (95% CI: 0.17, 2.19; p = .022) for midlingual height, 0.48 mm (95% CI: 0.18, 0.79; p = .002) for mesial height, and 0.24 mm (95% CI: -0.05, 0.53; p = .102) for distal height changes. Subgroup analyses revealed that flap elevation, the usage of a membrane, and the application of a xenograft or an allograft are associated with superior outcomes, particularly on midbuccal and midlingual height preservation.
    Journal of dental research. 06/2014;
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    ABSTRACT: Objective: Severe early childhood caries (SECC) is a debilitating form of tooth decay and is prevalent among lower socio-economic groups. Streptococcus mutans (SM) and Streptococcus sobrinus (SS) are major etiologic agents in SECC. SS is less common than SM but is more closely associated with high caries activity. Numerous SS and SM were isolated from plaques from a cohort of mother/child diads from a Northern Plains Indian Tribe. We aim to compare caries among individuals with SM only, SS only, both SM and SS and those without any mutans streptococci (MS). Method: Plaque samples were collected every 4 months for 3 years from 244 mother/child pairs from the birth of the child. Plaques from a subset (40-50 diads) were cultured on selective agar to isolate SM and SS colonies (PCR verified) to determine the presence of these species in plaque at each time point. Dental exams given concurrently with plaque sampling have provided caries data. Result: Roughly 30-35% of all isolated MS colonies are SS. About 60% or children and 72% of mothers harbor both SM and SS. Pending final analysis, the presence of both SM and SS in the plaque, of either mothers or children, appeared to associate with higher levels of tooth decay compared to individuals harboring only SM, SS or no MS. Conclusion: While plaque is a highly complex microbial community and caries is a multifactorial process, the presence of SS in this community could play a vital role in SECC that is rampant in this population. Analysis to explore the effect of SM and SS on the overall plaque community and their role in the development of caries in members of this population is underway. Analyses of the relationship among SM and SS and plaque are underway.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: The production of chemokines, cytokines, and biological mediators in peri-implant crevicular fluid (PICF) may differ from that in gingival crevicular fluid (GCF). Any differences among these anatomical locations may be used as biomarkers of periodontal and peri-implant health or early detection of periodontitis and peri-implantitis. Objectives: The objective was to determine the production and concentration of 13 biomarkers of inflammation in the PICF and GCF in an adult population enrolled in a regular maintenance program. Methods: PICF and GCF were collected from 45 females and 28 males (mean age, 59.95 with a standard deviation of 14.23; minimum age, 20; maximum age 86; and median age, 60). Concentrations of 13 biomarkers were determined with magnetic bead immunoassays (Millipore, Billerica, MA USA) in the Luminex 100 IS (Austin, TX) using Milliplex Analyst v5.1 (Millipore). Descriptive statistics, including sample size, mean, standard deviation, minimum, 25th percentile, median, 75th percentile and maximum, were computed for all biomarker outcomes (expressed as the median of the replicates). Differences of each outcome for the two sites within subject (i.e., the measurement at the implant site – the measurement at the control/tooth site) were calculated. Sign tests were performed to see if there was a difference in biomarker levels around dental implants vs. those around the natural tooth. Results: Levels of IL-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, IL-12, CRP, RANKL, osteoprotegerin, and adiponectin were all detected and concentrations did not differ significantly between the implant and control tooth sites. The data provided evidence at the 0.05 level for higher levels at the implant site than the control/tooth site for IL-17 (p=0.0225) and TNF-α (p=0.0319). Conclusion: Levels of IL-17 and TNF-α were higher at the implant site than at the control/tooth site, and may be contributing factors in the pathogenesis of peri-implantitis.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: Objective: Dental caries is the most common chronic disease of childhood. While children of all races and socioeconomic statuses get caries, they are highly prevalent in children from low socioeconomic statuses, specifically American Indian and Alaskan Native (AI/AN) children. We are currently conducting a large scale examination of SM transmission from mother to child in a Northern Plains Tribal Community. One component of this study is to determine total counts of Streptococcus mutans(SM) and Lactobacilli(LB) in plaque samples of mothers in the study cohort at baseline and compare these to total bacterial counts to determine the degree to which SM and LB dominate plaque flora. In addition, we are investigating the correlation between the above variables and caries status for each mother. Method: Plaque samples were spiral plated onto MSKB, Rogosa, and blood agar to determine SM, LB, and total oral bacterial counts respectively. Counts were determined using standard spiral plating methodology. The Wilcoxon rank-sum test was used to detect the difference in above variables between subjects with and without decay, while the Spearman rank correlation was conducted to evaluate the relationship between the variables. Result: Out of 214 mothers examined, 193 showed decay and 21 had no decay. Albeit weak, significant correlations were found between both DMFS and DSurf (total number of untreated decayed surfaces) and the following variables: SM levels, percent SM to total flora, LB levels, percent LB to total flora and the percent of the sum of SM and LB to total flora (p<0.05 in each instance). Also, the data revealed that mothers with decay had significantly greater LB than those without decay. Conclusion: According to this baseline data, we have determined that the relative high levels of SM and LB compared to the total flora correlate significantly with caries experiences in this population. Further analysis is continuing.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: Objectives: Streptococcus mutans (SM) is a primary microbiological agent of dental caries, a very prevalent chronic disease of childhood. Children from populations with lower socioeconomic status, particularly Hispanic, African-American, and American Indian, display a significantly higher incidence of caries. Our current study is focusing on transmission of SM genotypes from mother (or other designated primary caregiver) to child in an American Indian population. We are reporting here on the genotypic diversity and transmission of SM in 40 family groups (mother/child or mother/child/caregiver) from a Northern Plains Tribe. We are focusing on SM profiles of babies from birth to 16 months of age. Methods: Whole mouth plaque samples were collected from mother/child pairs and designated primary caregivers every 4 months. Samples were spiral plated onto selective and non-selective agars to obtain total flora, lactobacillus, and SM counts. SM isolates were identified by sugar fermentation profiles and genotyped with AP-PCR using OPA2 primer. Gels were analyzed and dendograms generated using GelCompar®IIv6.5. Results: Individual subjects display a range of 0-4 SM genotypes. Family groups show a range of 0-6 SM genotypes. In our data set, 62.5% of the children (25/40) have established SM colonization by 16 months. Of these children, 44% share at least 1 genotype with the mother and/or caregiver. In 8 of the 13 families with a designated primary caregiver, the mother and caregiver share at least one SM genotype. Conclusions: Our data show that there is homology of some SM genotypes in mother/child pairs and mother/child/caregiver groups. There are some genotypes observed in children that are not shared with mothers and/or primary caregivers and some shared within and across families. We continue the analyses of our data set focusing on SM genotype profiles and transmission in this population.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: Objective: Early childhood caries (ECC) is rampant among American Indian children, but there has been relatively little study of this problem. This paper reports on the prevalence of caries at the person, tooth and tooth surface level for a group of American Indian children at age 36 months. Method: Pregnant women from a Northern Plains Tribal community were recruited to participate in a longitudinal study of ECC and risk factors. Standardized dental examinations were completed on children and questionnaires were completed by mothers at baseline and when children were 4, 8, 12, 16, 22, 28 and 36 months of age. The exams were surface-specific for frank decay, and the presence of non-cavitated “white spot” lesions was recorded at the subject level. Result: The sample size was 232 mother-child pairs, and for the 36 month examinations, the mean age of the children was 35.4 months. As reported previously (IADR 2013), frank caries prevalence at 22 months was 49.6%. By 36 months of age, frank caries prevalence was 80.1%, with an additional 14.7% having only non-cavitated lesions. The maxillary incisors were most commonly affected, with individual maxillary incisor prevalence ranging from 44.8% to 53.0%. The mandibular molars were also commonly affected, with the range of individual mandibular molar caries prevalence ranging from 34.1% to 44.4%. In total, 10.9% of all erupted surfaces were affected by frank decay. The mean dmfs was 9.62, and of the total dmfs, nearly 62% was decayed, 31% was missing, and only 7% was filled. Conclusion: By the age of 36 months, dental caries is nearly universal in this population of American Indian children. Future analyses of these data will assess bacterial, behavioral, dietary and demographic variables as risk factors for ECC in this population.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: Objective: The aims of this study were to describe deciduous tooth eruption in an American Indian population, to compare patterns of eruption by gender and to contrast them with other populations. Method: A group of 239 mother-child dyads participated in a longitudinal oral health project conducted on the reservation of a Northern Plains tribe. Dental examinations were performed at baseline (approximately one month of age (±30 days) and target ages of 4, 8, 12, 16, 22, 28, and 36 months. Descriptive statistics, 95% confidence intervals and graphics were used to describe tooth eruption patterns, which addressed the number of erupted teeth, time to eruption, and the number of erupted surfaces. Findings were compared for males and females, and with published data from other populations. Result: There was no evidence of gender differences in the numbers of erupted teeth present over the longitudinal course (p>0.05). The mean number of erupted teeth at approximately 4, 8, 12, 16, 22, 28, and 36 months of age was 0.30, 3.68, 7.80, 12.49, 16.20, 18.93, and 19.95, respectively. Overall, there was an impression of early tooth eruption: natal teeth occurred in 4 of 239 children (1.67%); 16% had teeth present by age four months; 88% had teeth present by age 8 months. Observed patterns suggested that, on average, these children had more teeth present at age 12 months, and shorter times to eruption, than several other non-American Indian populations. Conclusion: Tooth eruption patterns in this Native American sample suggest a possible contributing factor to high levels of decay in deciduous teeth of Native American children: earlier eruption implies that teeth have longer exposure to risk of caries and thus greater potential for decay. These findings could have practical implications for childhood oral health care and parental oral health education in this American Indian community.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: Objective: Previous studies have shown that American Indian and Alaskan Native (AI/AN) children have a high incidence of decay at a young age. Few studies have assessed causative factors. The purpose of this paper is to assess the relationship between antibiotic exposure and oral flora of very young children from a Northern Plains Tribal Community. Method: The parent study was conducted to study ECC in a Northern Plains Tribal community, and focused on the transmission of cariogenic bacteria from mother to child. Mothers with newborns were recruited into the study between June 2009 and June 2010, resulting in 239 mother-child pairs enrolled. Follow-up visits were completed when the child was 4, 8, 12, 16, 22, 30, and 36 months (+30 days). At each visit, plaque samples were collected from the mother and child and S. mutans counts were obtained via selective media. All antibiotic records were obtained from Indian Health Service medical records and entered into a Microsoft Excel spreadsheet and combined with existing oral flora data for each child. This paper reports on oral flora at 16 months of age and previous antibiotic exposure. Result: Bacterial count and antibiotic data were available for 81 subjects at 16 month time point and were included in the analysis. The subjects had an average of 3.7 antibiotic episodes; 80% of the children had antibiotic exposure. Of these subjects, 25 of them had no S. mutans. No significant correlation between the number of antibiotic episodes from birth to 16 months and S. mutans levels was found (p=0.2806). Also, there was no significant correlation between the total number of days of antibiotic usage and S. mutans levels (p=0.9422). Conclusion: Our early findings suggest that antibiotics do not have a significant effect on S. mutans bacterial levels in these very high-risk children.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: Objective: To explore the relative utility of cross-sectional fluoride intake measures and Area-Under-the-Curve (AUC) measures of fluoride intake based upon longitudinal follow-up as predictors of dental fluorosis in the early permanent dentition, motivated by the lack of universal availability of longitudinal measures. Method: Multiple measures of fluoride intake were available for participants in the Iowa Fluoride Study, a cohort study of children recruited perinatally: intakes based upon dietary report at 6, 12, 24, 36 and 48 months of age (cross-sectional) and AUCs reflecting intake from birth until 12, 24, 36 and 48 months (longitudinal). All measures were available for 237 of 544 children participating in an associated study of genetic and environmental determinants of dental fluorosis. Quantitative definitions of dental fluorosis were based upon the number of affected teeth or zones based upon the Fluorosis Risk Index (FRI). Spearman correlational analyses were used to assess which fluoride intake measurements had the strongest correlations with fluorosis phenotypes; performance of competing predictors was assessed using the method of Dunn and Clark (1969). Result: Most fluoride intake variables were strongly correlated among themselves. Among cross sectional measures of fluoride intake, the strongest correlations with fluorosis outcomes were for fluoride intake at 36 months (r=0.22-0.27; all p<0.001); among longitudinal measures, it was AUC from birth to 48 months (r=0.24-0.31; all p<0.0002). There was no evidence that these intake measures differed significantly in predictive ability. Conclusion: These results suggest that cross-sectional fluoride intake measures may reasonably be used when longitudinal measures are not available. Similarly, if the stringent completeness criteria of AUC measures create significant missing data, substitution of cross-sectional measures results in increased sample size and greater statistical power. We recommend the use of the cross-sectional measurement at 36 months as a substitute for the AUC measures.
    AADR Annual Meeting & Exhibition 2014; 03/2014
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    ABSTRACT: OBJECTIVES: This is a 36 month birth-cohort study examining rampant early childhood caries (ECC) among American Indian children from a Northern Plains Tribal community. Regular oral exams, plaque samples, and caregiver interview questionnaires serve as a rich analytical source for ECC investigation. This paper reports on the prevalence of caries, as well as dmfs and its composition over the 36 month time course. METHODS: A total of 239 mother-child dyads participated in a longitudinal study of early childhood caries (ECC) and risk factors. Surface-specific exams for frank decay and non-cavitated white spot lesions occurred at baseline (approximately one month of age (±30 days) and target ages of 4, 8, 12, 16, 22, 28, and 36 months. RESULTS: Decay was first seen in seven teeth (6 maxillary incisors and 1 mandibular incisor) from five children at 8 months. The progression of caries prevalence was: 2.1% (N = 233, 8 mos), 14.9% (N = 235, 12mos), 31.8% (N = 233, 16 mos), 49.6% (N = 234, 22 mos), 69.2% (N = 227, 28 mos), and 80.2% (N = 232, 36 mos). Mean dmfs and its composition (D=decayed, M=missing, F=filled) were: 0.03 (8 mos: 100%
    AADR 2014; 03/2014
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    ABSTRACT: Dental implant abutments are fundamental prosthetic components within dentistry that require optimal biocompatibility. The primary aim of this cross-sectional study was to preliminarily assess differences in the pro-inflammatory cytokine and bone metabolism mediator protein expression in the peri-implant crevicular fluid (PICF) adjacent to transmucosal abutments. Abutments were fabricated from either titanium or zirconia in patients previously receiving single-tooth implant therapy. All subjects sampled in this study had an identical implant system and implant-abutment connection. Participants (n = 46) had an average time of clinical function for 22 months (6.2-72.8 months, ±SD 17 months) and received a clinical and radiographic examination of the implant site at the time of PICF sampling using a paper strip-based sampling technique. Cytokine, chemokine, and bone metabolism mediator quantities (picograms/30 s) were determined using a commercial 22-multiplexed fluorescent bead-based immunoassay instrument. A total of 19 pro-inflammatory cytokines and seven bone metabolism mediators were evaluated. Multivariable analyses provided no evidence of a group (titanium or zirconia), gender, or age effect with regard to the expression of pro-inflammatory mediators evaluated. Significant (P = 0.022) differences were observed for the bone mediator leptin, with titanium abutments demonstrating significantly elevated levels in comparison with zirconia. Osteopontin demonstrated a significant (P = 0.0044) correlation with age of the subjects. No significant differences in pro-inflammatory cytokine or bone metabolism mediator profiles were observed biochemically, with the exception of leptin, for the abutment biomaterials of titanium or zirconia The molecular PICF findings support the observed clinical biocompatibility of both titanium and zirconia abutments.
    Clinical Oral Implants Research 01/2014; · 3.43 Impact Factor
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    ABSTRACT: Purpose: Currently, research is lacking regarding the use of spill-proof beverage containers (SPBCs). The purpose of this study was to assess the relationship between daytime SPBCs use for sugared beverages, caries, socioeconomic status, and other covariates in high-caries risk 12- to 49-month-old children attending a Women, Infants and Children (WIC) program. Methods: Data were analyzed using baseline information from 415 Iowa WIC-enrolled children who participated in a psychoeducational study. Mothers completed a series of detailed questionnaires regarding their SES and their child's beverage consumption. Dental examinations using d1d2.3 (noncavitated and cavitated carious lesions) criteria were completed for the children. Bivariate relationships for consumption of any sugared beverage using SPBCs were assessed and followed by multivariable modeling using logistic regression (alpha=0.05). Results: Only 18 children (four percent) reported using SPBCs for any sugared beverage during the night versus 290 (70 percent) during the day. Daytime consumption of sugared beverages from SPBCs was less likely to be reported in older children (P.001) and Caucasians (P=.001). Conclusions: Iowa WIC children primarily consume sugared beverages using spill-proof beverage containers during the day; children who were younger and Hispanic or Caucasian were more likely to use SPBCs to consume sugared beverages.
    Pediatric dentistry 01/2014; 36(3). · 0.56 Impact Factor
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    ABSTRACT: Gene therapy using non-viral vectors that are safe and efficient in transfecting target cells is an effective approach to overcome the shortcomings of protein delivery of growth factors. The objective of this study was to develop and test a non-viral gene delivery system for bone regeneration utilizing a collagen scaffold to deliver polyethylenimine (PEI)-plasmid DNA (pDNA) [encoding platelet derived growth factor-B (PDGF-B)] complexes. The PEI-pPDGF-B complexes were fabricated at amine (N) to phosphate (P) ratio of 10 and characterized for size, surface charge, and in vitro cytotoxicity and transfection efficacy in human bone marrow stromal cells (BMSCs). The influence of the complex-loaded collagen scaffold on cellular attachment and recruitment was evaluated in vitro using microscopy techniques. The in vivo regenerative capacity of the gene delivery system was assessed in 5 mm diameter critical-sized calvarial defects in Fisher 344 rats. The complexes were ∼100 nm in size with a positive surface charge. Complexes prepared at an N/P ratio of 10 displayed low cytotoxicity as assessed by a cell viability assay. Confocal microscopy revealed significant proliferation of BMSCs on complex-loaded collagen scaffolds compared to empty scaffolds. In vivo studies showed significantly higher new bone volume/total volume (BV/TV) % in calvarial defects treated with the complex-activated scaffolds following 4 weeks of implantation (14- and 44-fold higher) when compared to empty defects or empty scaffolds, respectively. Together, these findings suggest that non-viral PDGF-B gene-activated scaffolds are effective for bone regeneration and are an attractive gene delivery system with significant potential for clinical translation.
    Biomaterials 10/2013; · 8.31 Impact Factor
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    ABSTRACT: Lauric acid (C12:0) and sapienic acid (C16:1Δ6) derived from human sebaceous triglycerides are potent antimicrobials found at the human skin surface. Long-chain bases (sphingosine, dihydrosphingosine and 6-hydroxysphingosine) are also potent and broad-acting antimicrobials normally present at the skin surface. These antimicrobials are generated through the action of ceramidases on ceramides from the stratum corneum. These natural antimicrobials are thought to be part of the innate immune system of the skin. Exogenously providing these lipids to the skin may provide a new therapeutic option, or could potentially provide prophylaxis in people at risk of infection. This article is part of a Special Issue entitled The Important Role of Lipids in the Epidermis and their Role in the Formation and Maintenance of the Cutaneous Barrier.
    Biochimica et Biophysica Acta 08/2013; · 4.66 Impact Factor
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    ABSTRACT: Oral mucosal and salivary lipids exhibit potent antimicrobial activity for a variety of Gram-positive and Gram-negative bacteria; however, little is known about their spectrum of antimicrobial activity or mechanisms of action against oral bacteria. In this study, we examine the activity of two fatty acids and three sphingoid bases against Porphyromonas gingivalis, an important colonizer of the oral cavity implicated in periodontitis. Minimal inhibitory concentrations, minimal bactericidal concentrations, and kill kinetics revealed variable, but potent, activity of oral mucosal and salivary lipids against P. gingivalis, indicating that lipid structure may be an important determinant in lipid mechanisms of activity against bacteria, although specific components of bacterial membranes are also likely important. Electron micrographs showed ultrastructural damage induced by sapienic acid and phytosphingosine and confirmed disruption of the bacterial plasma membrane. This information, coupled with the association of treatment lipids with P. gingivalis lipids revealed via thin layer chromatography, suggests that the plasma membrane is a likely target of lipid antibacterial activity. Utilizing a combination of two-dimensional in-gel electrophoresis and Western blot followed by mass spectroscopy and N-terminus degradation sequencing we also show that treatment with sapienic acid induces upregulation of a set of proteins comprising a unique P. gingivalis stress response, including proteins important in fatty acid biosynthesis, metabolism and energy production, protein processing, cell adhesion and virulence. Prophylactic or therapeutic lipid treatments may be beneficial for intervention of infection by supplementing the natural immune function of endogenous lipids on mucosal surfaces.International Journal of Oral Science (2013) 5, doi:10.1038/ijos.2013.28; published online 19 July 2013.
    International Journal of Oral Science 07/2013; · 2.72 Impact Factor
  • Dentomaxillofacial Radiology 07/2013; · 1.27 Impact Factor
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    ABSTRACT: Class III malocclusion is characterized by a composite of dentoskeletal patterns that lead to the forward positioning of the mandibular teeth in relation to the maxillary teeth and a concave profile. Environmental and genetic factors are associated with this condition, which affects 1% of the population in the United States and imposes significant esthetic and functional burdens on affected persons. The purpose of this study was to capture the phenotypic variation in a large sample of white adults with Class III malocclusion using multivariate reduction methods. Sixty-three lateral cephalometric variables were measured from the pretreatment records of 292 white subjects with Class II malocclusion (126 male, 166 female; ages, 16-57 years). Principal component analysis and cluster analysis were used to capture the phenotypic variation and identify the most homogeneous groups of subjects to reduce genetic heterogeneity. Principal component analysis resulted in 6 principal components that accounted for 81.2% of the variation. The first 3 components represented variation in mandibular horizontal and vertical positions, maxillary horizontal position, and mandibular incisor angulation. The cluster model identified 5 distinct subphenotypes of Class III malocclusion. A spectrum of phenotypic definitions was obtained replicating results of previous studies and supporting the validity of these phenotypic measures in future research of the genetic and environmental etiologies of Class III malocclusion.
    American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 07/2013; 144(1):32-42. · 1.33 Impact Factor
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    ABSTRACT: Objectives: The prevalence and severity of dental caries is very high among young American Indian children, yet little is known about caries risk factors in this population or why some of these children remain caries free. The purpose of this paper is to report preliminary assessment of risk factors for caries in a group of 22-month-old American Indian children. Methods: Expectant mothers from a Northern Plains Tribal community were recruited to participate in an ongoing longitudinal study of risk factors for caries in their children. Risk factor data was collected by questionnaire at baseline and when children were 4, 8, 12, 16 and 22 months of age. Risk factor data included demographic, dietary, bacteriological and maternal factors. One of four trained examiners assessed caries in children at these same ages and in mothers at baseline. For these exams, surface-specific caries data were collected and the presence of pre-cavitated “white spot” lesions was recorded at the subject level. This paper reports on demographic and maternal factors associated with children’s caries at 22 months. Results: The sample size was 234 mother-child pairs, with mean ages of 23.75 years for mothers at baseline and 21.2 months for children. Caries prevalence was 49.6%, while an additional 24.8% had white spot lesions only. Caries was significantly (p<0.05) associated with higher numbers of teeth erupted at previous exams and mothers’ baseline DMFT. In addition, caries prevalence was 100% for children whose mothers did not attend high school declining to 33% among children of college graduates (p=0.004). Child sex and ethnicity, household size and family income were not associated with caries. Conclusions: Dental caries prevalence is very high among this group of American Indian children, with earlier tooth eruption, higher maternal caries experience and lower maternal education levels associated with children’s caries.
    IADR/AADR/CADR General Session and Exhibition 2013; 03/2013

Publication Stats

1k Citations
173.07 Total Impact Points

Institutions

  • 2002–2014
    • University of Iowa
      • • College of Dentistry
      • • Dows Institute for Dental Research
      • • Department of Periodontics
      • • Department of Preventive and Community Dentistry
      • • Department of Orthodontics
      • • Department of Operative Dentistry
      Iowa City, Iowa, United States
  • 2010
    • Loma Linda University
      Loma Linda, California, United States
  • 2008
    • CUNY Graduate Center
      New York City, New York, United States
  • 1994–2008
    • Duke University Medical Center
      • • Division of Medical Genetics
      • • Department of Pediatrics
      • • Department of Immunology
      Durham, NC, United States
  • 2005
    • Virginia Commonwealth University
      • School of Dentistry
      Richmond, VA, United States
    • Chulalongkorn University
      • Department of Community Dentistry
      Bangkok, Bangkok, Thailand
  • 2004
    • King's College London
      Londinium, England, United Kingdom
    • University of Michigan
      • Department of Cariology, Restorative Sciences and Endodontics
      Ann Arbor, MI, United States
  • 1995–2001
    • Case Western Reserve University
      • • MetroHealth Medical Center
      • • Department of Epidemiology and Biostatistics
      Cleveland, OH, United States