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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Cephalometric variability among siblings

Marcks, Katharine Luskin 24 June 2019 (has links)
OBJECTIVE: To determine whether multiple siblings in a family resemble one another in terms of their craniofacial characteristics.  METHODS: This pilot study was conducted retrospectively using the Forsyth Twin sample. 32 families were included, each with at least 4 siblings who had lateral cephalometric radiographs taken after skeletal maturity was documented, for a total of 142 subjects. Headfilms were digitized and skeletal landmarks located to allow measurement of 6 parameters indicating sagittal jaw relationships and vertical status.  Dixon’s Q test was applied to identify any outliers in a family for a given parameter. Manhattan distance quantified similarity among siblings per parameter. Scatter plots visually displayed subject’s measure relative to the mean and standard deviation of each parameter to assess clinical relevance.  RESULTS: 11 families (34.4%) had no outliers on any of the 6 parameters, 13 families (40.6%) had outliers on only 1 parameter, and 8 families (25%) had outliers on at least 2 parameters. Our analyses identified 29 individuals with at least one outlying measure (20.4%). Of those, only 2 individuals (1.4%) were significantly different from their siblings for more than 1 measurement.  Although the majority of the families did not demonstrate a statistical outlier for any given measurement, the ranges were clinically relevant as they might lead to differing orthodontic treatment plans. CONCLUSIONS: Although families are generally not statistically dissimilar in their craniofacial characteristics as measured on cephalometric radiographs, measurements from siblings cannot be used to predict the measurements of another sibling in a clinically meaningful way.
112

Silicon, calcium and phosphate effect on human dental pulp cell cultures

Alsenan, Jomana F. 30 June 2019 (has links)
This study was designed to investigate the odontogenic effects of Silicon, Calcium and Phosphorous on human dental pulp cells (hDPCs). hDPCs derived from extracted pristine teeth were cultured in growth media with supplements of Si 25ppm, Si 25ppm+Ca 8.3ppm, Si 25ppm+Ca 8.3ppm+P 4.16ppm, Si 50ppm, Si 50ppm+Ca 16.7ppm, Si 50ppm+Ca 16.7ppm+P 8.3ppm and media without additional supplement as control, for the time intervals of 16 hours, 7, 12, and 21 days. Also, HDPCs were cultured in growth media with supplements of inorganic phosphate (Pi) in 0 ppm, 2 ppm, 4 ppm, 5 ppm, 8 ppm, for the time intervals of 16 hours, 7, 14, and 21 days. Cell proliferation rates were measured by the optical density of crystal violet dye stained cells. ALP activity was measured by fluorometric assay. Expression of Dentin Sialoprotein (DSP) was measured by ELISA. Mineralization of cultures was measured by Alizarin Red staining. Culture with 50ppm supplemental Si at day 21 yield significantly higher levels of ALP activity, DSP expression and mineralization (P<0.05) compared to the control group and other supplemented groups. Cultures with 2, 4, 5 and 8 ppm supplemental Pi yield significantly higher levels of ALP activity (P<0.05) compared to the control group at day 7. Cultures with 5 ppm Pi supplement showed significantly higher levels of DSP expression (P<0.05) compared to the control group and the other groups at day 7. Cultures with Si 25ppm+Ca 8.3ppm supplemental and Si 50ppm+Ca 16.7ppm supplemental displayed significantly higher cell proliferation rates compared to the control group at day 12 and at day 21 (P<0.05). Cultures with 2, 4 and 5 ppm supplemental Pi displayed significantly higher cell proliferation rates compared to the control group at day14 (P<0.05) and at day 21 (P<0.05). Supplemental silicon in concentration of 50 ppm could significantly induce differentiation and mineralization of normal human dental pulp cells. Calcium has a synergetic effect in up-regulating the proliferation rates. Supplemental Pi in concentration of 5 ppm could significantly induce proliferation and odontogenesis of hDPCs. This is the first report to demonstrate Si, Ca and P induced odontogenesis of hDPCs cultures. / 2021-06-30T00:00:00Z
113

The relation between sleep disturbance and the size of the upper airway in children usint the acoustic pharyngometer/rhinometer

Alsadiq, Salam Ahmad 22 July 2019 (has links)
OBJECTIVE: The objective of this study is to evaluate the relation between the size of the upper airway using the Acoustic Pharyngometry/Rhinometry and the sleep disorders in children. Methods: Children between the ages 3-18 years with or without sleep disturbance who attended the Pediatric dental clinic and Orthodontic clinic at Henry M. Goldman School of Dental Medicine were evaluated to participate in the study. Based on BEARS questionnaires (sleep disturbance screening tool for pediatric patients) the participants were then divided to either the control or the case group. PSQ (pediatric sleep questionnaires) were used to evaluate the sleep pattern of the participating subjects. Subjects were then examined using the Eccovision Acoustic Pharyngometry (AP) and Acoustic Rhinometry (AR) (Hood Laboratories, Pembroke, MA) to obtain the airways measurements. RESULTS: Regression analysis of the Acoustic Pharyngometry measurements showed statistical significant differences in the Pharyngometry Minimum cross sectional area (PMCSA) between children with sleep disturbance and children without sleep disturbance after adjusting for gender, race and age (p=0.01). The analysis of the Rhinometry volume (RV) showed statistical significant results between children with sleep disturbance and children without sleep disturbance after adjusting for gender, race and age (p<0.05). Regression analysis of air resistance (RAR) showed statistical significant difference between children with sleep disturbance and children without sleep disturbance when controlling for gender, race and age (p=0.03). CONCLUSIONS: RV and PMCSA were significantly lower in children with sleep disorder breathing (SDB) compared to children without SDB. / 2021-07-22T00:00:00Z
114

The role of WDR72 in amelogenesis

Husein, Dina R. 05 August 2019 (has links)
Amelogenesis undergoes two stages; first a secretory stage followed by a maturation stage. During maturation, ameloblasts secrete kallikrein-4 (KLK4) enamel protease responsible for extra-cellular matrix degradation leading to ions deposition and enamel mineralization. Amelogenesis Imperfecta (AI) is a rare genetic disease affecting dental enamel formation. Patients with AI suffer from dental and esthetic problems. AI due to WDR72 mutations have weak and soft enamel phenotype similar to the phenotype seen with KLK4 mutations. The aims of this study were to investigate the stage at which WDR72 is expressed during amelogenesis and to investigate whether WDR72 has an effect on the extra-cellular location of KLK4. Immunohistochemistry with anti-WDR72 antibody was performed on WDR72 wild-type and knock-out rat molars to investigate the expression of WDR72 during secretory and maturation stages of amelogenesis. Mouse ameloblast-like cells were used to co-transfect WDR72 and KLK4 to examine the effects of WDR72 on KLK4 extra-cellular location. Our immunohistochemical staining data demonstrated that WDR72 was detected in the wild type ameloblasts during the maturation stage of amelogenesis. Our data also showed that the extracellular location of KLK4 was increased when WDR72 was co-transfected. In conclusion, our results demonstrated that WDR72 is highly expressed in ameloblasts at the maturation stage and that WDR72 is necessary for KLK4 extracellular location. / 2021-08-05T00:00:00Z
115

Investigation of new regenerative endodontic therapies utilizing in vitro and non-human primate models

Raymond, Richard 01 July 2011 (has links)
July 2011 "A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry."
116

Healos® versus Regenaform® in guided bone regeneration : a case series with histology and computed tomography

Lorenz, Brock 01 January 2013 (has links)
"A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry." Objective: To compare the differences in new bone formation between Regenaform® (control) and a new material Healos® (test) when used with GBR (guided bone regeneration). Background: Subsequent to loss of teeth, supporting alveolar bone is predictably lost, comprising optimal dental implant placement. GBR is a procedure that augments deficient bone in preparation for a dental implant. Methods: Subjects in need of a dental implant but with insufficient bone were recruited to participate in the study. The control group received GBR with Regenaform® grafting material and the experimental group received GBR with Healos® grafting material. Implant placement into the GBR sites was performed six months after GBR surgery. Bone regeneration was assessed by comparison of pre- and post-operative cone-beam CT scans (CBCT) and dental stone models. At the time of implant placement, bone cores that would normally be discarded were obtained from four control group sites and four experimental sites and were analyzed histologically. Results: Comparison of CBCTs showed the horizontal bone augmentation obtained with GBR using Healos® graft material is much less compared to GBR using Regenaform® (1.57 mm versus 2.81 mm). All Healos® sites exhibited delayed short-term healing with excessive erythema, edema and suppuration. Histologic analysis shows that Healos® heals with similar vital bone and similar marrow and fibrous tissue compared to Regenaform®. Conclusion: The use of Healos® grafting material for use in GBR cannot be recommended when more predictable grafting materials such as Regenaform® are available.
117

Comparison of methods to remove fit-disclosing residue on the retention of cast ceramo-metal crowns

Brincefield, Ada 01 March 2011 (has links)
March 2011 A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry.
118

Comparison of leakage among different screw-access sealing materials for temporary implant-supported screw-retained crowns

Roman, Katherine 01 January 2014 (has links)
A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry.
119

Microtensile bond strength of composite resin to sound dentin following application of chemical collagen crosslinkers

Dutra, Kenya 01 January 2015 (has links)
A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry.
120

Effect of 35% sodium ascorbate on microtensile bond strength of composite resin immediately after bleaching

Ismail, Eman 01 January 2015 (has links)
Background: Sodium ascorbate has been recently tested to reverse the temporary weakening of composite bonding when its application is done immidiately after bleaching. This study compared the microtensile bond strength of immediate and delayed bonding of composite after bleaching, with and without the application of 35% sodium ascorbate. Objective: to assess the effect of 35% sodium ascorbate (SA) (Sigma-Aldrich Co.) on microtensile bond strength of dentin immediately after bleaching with 35% hydrogen peroxide (Pola Office/SDI). Methods: Twenty-five sound human 3rd molars were collected in order to obtain one hundred twenty five specimens. Teeth were randomly divided into five groups: Grp1 (bleaching + immediate restoration), Grp2 (bleaching + delayed restoration), Grp3 (bleaching + SA + immediate restoration), Grp4 (bleaching + SA + delayed restoration), Grp5 (Control-no treatment). After bleaching, but prior to restoration, Grps 2 & 4 were stored for 1 week in deionized water at 37°C. All samples were restored using Optibond Solo Plus (Kerr) and Filtek Supreme Ultra (3M/ESPE) following manufacturers' instructions. Teeth were sectioned into 1x1 mm bars, obtaining around 10 bars from each tooth. Microtensile bond strength was measured with a universal testing machine (Instron, model 8841) at a crosshead speed of 0.5 mm/min. Results: Descriptive statistics revealed that Grp1 (positive control) showed significant reduction in microtensile bond strength (34.17 ± 10.78). Grp5 (negative control)(45.83 ± 19.32), Grp2 (standard of care)(45.36± 16.57), Grp3 (45.06 ± 20.91) and Grp4 (44.73 ± 16.85) showed statistically similar microtensile bond strength. One-way ANOVA was used to determine if differences were evident between the five groups. Microtensile bond strength differed significantly across the five groups (F (4, 1073.81) = 3.54, p = .007) Tukey's post-hoc comparisons of the five groups showed significant differences between Grp 1 and all other groups 2,3,4 and 5. Conclusion: Microtensile bond strength was improved significantly after the application of 35% sodium ascorbate when restored with resin composite immediately after bleaching. Grants: This study was funded by NSU, Health Profession Division.

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