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Preventive effect of an iron varnish on bovine enamel erosion in vitro

KATO, Melissa Thiemi; ITALIANI, Flavia de Moraes; ARAUJO, Juliana Julianelli de; GARCIA, Marina Duarte; SALES-PERES, Silvia Helena de Carvalho; BUZALAF, Marilia Afonso Rabelo
Fonte: ELSEVIER SCI LTD Publicador: ELSEVIER SCI LTD
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
26.81%
Objective: The aim of this study was to evaluate, in vitro, the effect of an experimental varnish containing iron on the dissolution of bovine enamel by carbonated beverage. Methods: Eighty specimens were randomly allocated to four groups (n = 20 per group), according to the following treatments: Fe varnish (FeV, 10 mmoL/L Fe), F varnish (FV, 2.71% F), placebo varnish (PV) and control (not treated, NT). The varnishes were applied in a thin layer and removed after 6 h. Then, the samples were submitted to six cycles, alternating re- and demineralisation (only 1 day). Demineralisation was performed with the beverage Coca-Cola (R) (10 min, 30 mL/block) and remineralisation with artificial saliva for I h. In order to determine the amount of enamel dissolved, the wear was analysed by profilometry. Data were analysed by ANOVA and Tukey`s test (p < 0.05). Results: The mean wear (+/- S.E.) was significantly lesser for the FeV (0.451 +/- 0.018 mu m) when compared to the other treatments. The FV caused significantly less wear (0.554 +/- 0.022 mu m) when compared to PV (0.991 +/- 0.039 mu m) and NT (1.014 +/- 0.033), which did not significantly differ from each other. Conclusions: The results suggest that the iron varnish can interfere with the dissolution of dental enamel in the presence of acidic beverages. (C) 2008 Elsevier Ltd. All rights reserved.

MEPE expression in osteocytes during orthodontic tooth movement

Gluhak-Heinrich, J.; Pavlin, D.; Yang, W.; MacDougall, M.; Harris, S.E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
26.32%
MEPE and DMP1 may play a role in mineralisation and demineralisation within the osteocyte microenvironment. Our earlier studies showed that DMP1 is mechanically responsive [Gluhak-Heinrich J, Ye L, Bonewald LF, Feng JQ, MacDougall M, Harris SE, et al. Mechanical loading stimulates dentin matrix protein 1 (DMP1) in osteocytes in vivo. J Bone Min Res 2003;18(5):807–17].

Differential Nuclear and Mitochondrial DNA Preservation in Post-Mortem Teeth with Implications for Forensic and Ancient DNA Studies

Higgins, Denice; Rohrlach, Adam B.; Kaidonis, John; Townsend, Grant; Austin, Jeremy J.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 19/05/2015 EN
Relevância na Pesquisa
16.5%
Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements. However, little is known about the post-mortem kinetics of DNA degradation and whether the rate of degradation varies between nuclear and mitochondrial DNA or across different skeletal tissues. This knowledge, along with information regarding ante-mortem DNA distribution within skeletal elements, would inform sampling protocols facilitating development of improved extraction processes. Here we present a combined genetic and histological examination of DNA content and rates of DNA degradation in the different tooth tissues of 150 human molars over short-medium post-mortem intervals. DNA was extracted from coronal dentine, root dentine, cementum and pulp of 114 teeth via a silica column method and the remaining 36 teeth were examined histologically. Real time quantification assays based on two nuclear DNA fragments (67 bp and 156 bp) and one mitochondrial DNA fragment (77 bp) showed nuclear and mitochondrial DNA degraded exponentially...

Antibacterialagentsin composite restorationsfor the prevention of dentalcaries

Cenci, Tatiana Pereira; Cenci, Maximiliano S??rgio; Fedorowicz, Zbys; Marchesan, Melissa A
Fonte: Cochrane Collaboration Publicador: Cochrane Collaboration
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
16.5%
Dental caries is a multifactorial disease in which the fermentation of food sugars by bacteria from the bio???lm (dental plaque) leads to localised demineralisation of tooth surfaces, which may ultimately result in cavity formation. Resin composites are widely used in dentistry to restore teeth. These restorations can fail for a number of reasons, such as secondary caries, excessive wear, marginal degradation, tooth sensitivity, pulpal death, and restorative material fracture. Caries adjacent to restorations is one of the main causes for restoration replacement. The presence of antibacterials in both the ???lling material and the bonding systems would theoretically be able to affect the initiation and progression of caries adjacent to restorations. Objectives To assess the effects of antibacterial agents incorporated into composite restorations for the prevention of dental caries. Search methods We searched the following databases in February 2009: theCochraneOralHealthGroup???sTrialsRegister;theCochraneCentralRegister ofControlledTrials(CENTRAL)(TheCochraneLibrary2009,Issue1);MEDLINEviaOVID(1950toFebruary2009)without???lter; and EMBASE via OVID (1980 to February 2009) without ???lter. Selection criteria Randomised controlled clinical trials(RCTs) comparing resin composite restorations containing antibacterial agentswithnon-antibacterial containing composite restorations. Data collection and analysis Two review authors conducted screening of studies in duplicate and independently...

Studies on dental erosion: An in vitro model of root surface erosion

White, I.; McIntyre, J.; Logan, R.
Fonte: Australian Dental Assn Inc Publicador: Australian Dental Assn Inc
Tipo: Artigo de Revista Científica
Publicado em //2001 EN
Relevância na Pesquisa
26.91%
Most research on dental erosion has focused on erosion in enamel. However, the increasing retention of teeth into old age has increased the potential for root surface erosion. The nature and kinetics of root surface erosion have not yet been adequately explored. The objective of this project was to develop an in vitro model of root surface erosion in order to investigate the polarised light microscopy of controlled erosion and the histology and rate of demineralisation of this process in root cementum/dentine. The results demonstrate a process quite different in outcome from that in enamel erosion. Erosion results in loss of volume of enamel. However, it leaves a root surface softened though with little volume loss so long as the demineralised collagen remains hydrated. The polarised light histology was similar to that seen in root surface caries. The rate of erosive demineralisation of tooth roots by selected acids was investigated, with differing rates of demineralisation similar to that seen in enamel erosion observed. The process of erosion showed evidence of significant diffusion control.; I. White, J. McIntyre and R. Logan; The document attached has been archived with permission from the Australian Dental Association (8th Jan 2008). An external link to the publisher’s copy is included.

Corticotomy enhanced orthodontics.

Jong, Mun Jing
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2012
Relevância na Pesquisa
26.78%
The main aims of this study were to evaluate the effect of both a flap and corticotomy procedure on orthodontic tooth movement in rats and to compare the bone changes against a control group. Furthermore, the study aimed to introduce a new design for an appliance, which would allow buccal tooth movement in a rat model. Male Sprague-Dawley rats (n=36) aged 6-8 weeks were obtained from Laboratory Animal Services (Adelaide University) with ethics approval from The University of Adelaide Animal Ethics Committee (Project number: M-2009-172). There were 3 control groups, each with 6 rats: nil intervention; flap surgery; corticotomy procedure. These formed the baseline comparison to the experimental groups: tooth movement only; flap surgery and tooth movement; and corticotomy with tooth movement; 4 rats were excluded due to anaesthetic death or appliance failure but were replaced with ethics approval from The University of Adelaide Animal Ethics Committee (Project number: M-2009-172B) such that 6 rats remained in each group. [table omitted] The timeline for the experiment was 7 days with a Calcein bone label injection at 3 days prior to appliance insertion, an Alizarin Red bone label injection at 5 days after appliance insertion, and sacrifice at 7 days after appliance insertion. Throughout the experimental period...

'Mineral maintenance' of dental structures in caries and erosive tooth wear: an holistic model

Kaidonis, J.; Ranjitkar, S.; Townsend, G.
Fonte: University of Adelaide Press; Australia Publicador: University of Adelaide Press; Australia
Tipo: Parte de Livro
Publicado em //2012 EN
Relevância na Pesquisa
26.32%
it is argued that dental structures within the oral environment have evolved with an ability to resist dissolution when exposed to acidic conditions, and to promote remineralisation after damage has occured. It is hypothesised that dietry acids acted as one of the selected forces in the evolution of the oral environment. It appears that a balance was achieved in hunter-gatherer populations, with the composition and action of saliva, and associated oral biofilms, evolving to protec the teeth against dietry acids. However, in the relatively short period of time since the development of farming and especially with the adoption of modern cultural practices, changes in diet have overwhelmed the oral environment, creating an imbalance. In general, the vast increase in consumption of acidic foods and drinks has decreased the protective mechanisms of saliva. Similarly, the increased consumption of sugar has changed the ecology of oral biofilms, leading to and maintaining a lower oral pH. A combination of these factors has tipped the balance towards demineralisation and icreased the risk of oral diseases, such as dental caries and erosive wear, that are prevalent in many of today's societies.; John Kaidonis, Sarbin Ranjitkar and Grant Townsend

Differential nuclear and mitochondrial DNA preservation in post-mortem teeth with implications for forensic and ancient DNA studies

Higgins, D.; Rohrlach, A.B.; Kaidonis, J.; Townsend, G.; Austin, J.J.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
Relevância na Pesquisa
16.5%
Major advances in genetic analysis of skeletal remains have been made over the last decade, primarily due to improvements in post-DNA-extraction techniques. Despite this, a key challenge for DNA analysis of skeletal remains is the limited yield of DNA recovered from these poorly preserved samples. Enhanced DNA recovery by improved sampling and extraction techniques would allow further advancements. However, little is known about the post-mortem kinetics of DNA degradation and whether the rate of degradation varies between nuclear and mitochondrial DNA or across different skeletal tissues. This knowledge, along with information regarding ante-mortem DNA distribution within skeletal elements, would inform sampling protocols facilitating development of improved extraction processes. Here we present a combined genetic and histological examination of DNA content and rates of DNA degradation in the different tooth tissues of 150 human molars over short-medium post-mortem intervals. DNA was extracted from coronal dentine, root dentine, cementum and pulp of 114 teeth via a silica column method and the remaining 36 teeth were examined histologically. Real time quantification assays based on two nuclear DNA fragments (67 bp and 156 bp) and one mitochondrial DNA fragment (77 bp) showed nuclear and mitochondrial DNA degraded exponentially...

Do educational methods affect students’ ability to remove artificial carious dentine? A randomised controlled trial

Rosa, Q. F.; Barcelos, T. M.; Kaizer, M. R.; Montagner, A. F.; Sarkis-Onofre, Rafael; Masotti, Alexandre Severo; Jardim, Patricia dos Santos; Cenci, Tatiana Pereira; Oliveira, Elenara Ferreira de; Cenci, Maximiliano Sérgio
Fonte: European Journal of Dental Education Publicador: European Journal of Dental Education
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.59%
This trial aimed to evaluate the influence of two educational methods on students’ ability to remove artificial carious dentine. Traditional lecture and lecture plus a live demonstration of artificial carious tissue removal were compared in a blind two parallel-group design. Twenty-six students were randomly divided into two groups, and their skills were evaluated according to the following criteria: time spent on the dentine excavation procedure (in min), students’ perceived confidence in conducting the procedure(graded assessed on a scale from 0 to 10), and the outcome of artificial carious tissue removal, evaluated by measuring the residual dyed artificial carious dentine layer(in lm). Statistical analyses were carried out using a t-test to compare the students’confidence and time spent on the procedure, and a two-way ANOVA was used to compare residual artificial decayed dentine with educational methods and tooth region (incisal, medium, and cervical thirds) as factors. There were no differences between the methods regarding excavation time (P = 0.898) and students’ confidence (P = 0.382). The residual artificial carious dentine results showed that the educational method (P < 0.001) and cavity region (P < 0.001) were statistically significant...