The Effect of Study Design on in situ Treatment of Carious Enamel Lesions

1992 ◽  
Vol 71 (3_suppl) ◽  
pp. 814-818 ◽  
Author(s):  
P.G. Vernon ◽  
S.J. Raven ◽  
R.J. Gilbert ◽  
T.A. Parr ◽  
K.A. Dundon
Keyword(s):  
Mineral Content ◽  
Included Study ◽  
Caries Experience ◽  
Length Frequency ◽  
Fluoride Toothpaste ◽  
Human Enamel ◽  
Mineral Levels ◽  
Adult Volunteers ◽  
Mineral Changes

The aim of this exploratory study was to investigate the influence of several factors on changes in the mineral content of carious enamel lesions treated in situ. The study involved 36 adult volunteers who used either a non-fluoride toothpaste or one of two fluoride toothpastes (1000 or 1500 ppm F). Human enamel specimens were prepared and attached to partial dentures as described previously (Schäfer, 1989) and treated in situ for between three and six weeks. The mineral content of lesions was determined by microradiography and computerized densitometry. The factors investigated in this study included study length, frequency of treatment, trial design, patient compliance, patient diet, and previous caries experience of the patient. The effects observed were small, relative to that of the treatment, and not statistically significant (p > 0.05). However, the trends in the data were all as would be intuitively predicted. Study duration correlated positively with observed lesion mineral content. Lesions worn by panelists using a fluoride toothpaste for six weeks contained greater levels of mineral with respect to placebo than did those in panelists on a three-week study. The residual variations in the three phases of the study were found to be similar, suggesting that there is no advantage in these studies having a cross-over design. Brushing frequency also correlated positively with observed lesion mineral content, with panelists brushing three times per day with a fluoridated dentifrice having lesions with greater levels of mineral, with respect to placebo, than those brushing twice per day. Overall, no clear relationship between reported diet and changes in lesion mineral levels was apparent. However, increased frequency of sugar intake was associated with lower levels of mineral in lesions. No correlation was seen in this study between lifelong caries experience of panelists (DMFT) and observed mineral changes during the test period.

Demineralization and Remineralization Evaluation Techniques

1992 ◽  
Vol 71 (3_suppl) ◽  
pp. 924-928 ◽  
Author(s):  
J. Arends ◽  
J.J. ten Bosch
Keyword(s):  
Light Scattering ◽  
Mineral Content ◽  
Polarized Light ◽  
Cross Sectional ◽  
Main Emphasis ◽  
Measuring Techniques ◽  
Mineral Loss ◽  
Mineral Changes

This paper compares the experimental techniques utilized to assess the de- or remineralization of enamel or dentin in intra-oral studies. In in situ studies, it is important for one to know how much mineral has been lost or gained, and where the loss or gain occurred. The main emphasis in this paper is on techniques suitable for direct or indirect mineral quantification. The measuring techniques considered are microradiography, iodine absorptiometry, various microhardness tests, polarized light, light-scattering, iodide permeability, and wet chemical analysis. The various techniques are compared concerning suitability for the determination of mineral content in vol% (or wt%), mineral changes in vol% μm (or kg.m–2), and mineral distributions. Furthermore, sample preparation, the importance of protein penetration, nominal mineral loss range, the estimated mineral loss threshold, and the applicability to dentin are compared and considered. It is concluded that, although more than ten techniques are available for the measurement of changes after de- or remineralization in situ, transverse microradiography is the most practical technique for the direct and quantitative measurement of mineral content, mineral changes, and mineral distributions. Cross-sectional microhardness testing and light-scattering are also practical indirect techniques for quantitative mineral loss (or gain) determinations in intra-oral studies.

Matrix and Mineral Changes in Developing Enamel

1979 ◽  
Vol 58 (2_suppl) ◽  
pp. 871-882 ◽  
Author(s):  
C. Robinson ◽  
H.D. Briggs ◽  
P.J. Atkinson ◽  
J.A. Weatherell
Keyword(s):  
Mineral Content ◽  
Inorganic Ions ◽  
Organic Matrix ◽  
Small Samples ◽  
Enamel Organ ◽  
Enamel Matrix ◽  
Subsequent Loss ◽  
Matrix Components ◽  
Significant Concentration ◽  
Mineral Changes

An investigation of the changes taking place in the enamel and the enamel organ during enamel development has been carried out by analyzing small samples of tissue dissected from developing incisors of rat and bovine incisors. Observations showed that the synthesis of the enamel matrix and its subsequent loss were associated chiefly with a change in the major matrix components. This consisted of a selective loss of amelogenin components prior to secondary mineralization. Before this loss, some increase in the proportion of smaller molecular weight components suggested the possibility of limited breakdown. Even at the earliest stages examined, significant concentration of mineral ions was present. This increased steeply after most of the organic matrix had been removed. The Ca/P ratio of this mineral was constant throughout development. The concentration of minor inorganic ions (F, Mg and CO3) decreased as the tissue developed and a tendency was observed for certain ions (F, 32PO4) to penetrate and concentrate in the enamel, apparently as a consequence of the lost matrix being replaced by water, just prior to the steep increase in mineral content of the tissue.

scholarly journals Biofilm three-dimensional architecture influences in situ pH distribution pattern on the human enamel surface

2017 ◽  
Vol 9 (2) ◽  
pp. 74-79 ◽  
Author(s):  
Jin Xiao ◽  
Anderson T Hara ◽  
Dongyeop Kim ◽  
Domenick T Zero ◽  
Hyun Koo ◽  
...  
Keyword(s):  
Distribution Pattern ◽  
Three Dimensional ◽  
Enamel Surface ◽  
Ph Distribution ◽  
Human Enamel

scholarly journals Composition of dental plaque formed in the presence of sucrose and after its interruption

2003 ◽  
Vol 14 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Jaime Aparecido Cury ◽  
Aline Soler Marques ◽  
Cíntia Pereira Machado Tabchoury ◽  
Altair Antoninha Del Bel Cury
Keyword(s):  
Crossover Study ◽  
Dental Plaque ◽  
Sucrose Solution ◽  
Inorganic Phosphorus ◽  
Deionized Water ◽  
The Other ◽  
Low Concentration ◽  
Human Enamel ◽  
Two Stages

Since dental plaque reservoirs of fluoride (F), calcium (Ca) and inorganic phosphorus (Pi) are susceptible to decreases in pH, this in situ crossover study was conducted to test the hypothesis that the low concentration of these ions in plaque, formed in the presence of sucrose, could be attributed merely to the fermentation of this sugar. Eleven volunteers wore palatal appliances containing 6 human enamel blocks during two stages. In each stage, the treatments were either 20% sucrose solution or distilled deionized water, which were dripped onto the blocks 8 times a day. After 28 days, in each stage, the dental plaque formed on two blocks was collected, the treatment was inverted and after a further 24 and 48 h, the biofilm formed was collected from the other blocks. The concentration of acid-soluble F, Ca and Pi, and the concentration of insoluble polysaccharide (IP) were determined in the dental plaque. Statistically lower concentrations of F, Ca and Pi, and a higher concentration of IP were found in the 28-day biofilm formed in the presence of sucrose than in its absence; after the treatment inversion the change in F, Ca and Pi was not statistically significant, but the IP concentration changed significantly. The hypothesis was rejected because change in concentration of F, Ca and Pi is not due to fermentation of the sucrose.

The Effect of Lesion Characteristic on Remineralization and Model Sensitivity

1992 ◽  
Vol 71 (3_suppl) ◽  
pp. 811-813 ◽  
Author(s):  
F. Schäfer ◽  
S.J. Raven ◽  
T.A. Parr
Keyword(s):  
Real Life ◽  
High Sensitivity ◽  
Lesion Size ◽  
Experimental Conditions ◽  
Treatment Groups ◽  
Human Enamel ◽  
Enamel Sample ◽  
Two Factors ◽  
Treatment Bias

A major criterion for assessing the value of any experimental model in scientific research is the degree of correspondence between its results and data from the real-life process it is designed to model. Intra-oral models aimed at predicting the anti-caries efficacy of toothpastes or other topical treatments should therefore be calibrated against treatments proven to be effective in a caries clinical trial. For this to be achieved, it is necessary that a model with high sensitivity be designed, while at the same time retaining relevance to the process to be modeled. This means that the effects of the various experimental conditions and parameters of the model on its performance must be understood. The purpose of this paper was to assess the influence of two specific factors on the performance of an in situ enamel remineralization model, which is based on human enamel slabs attached to partial dentures. The two factors are initial lesion severity and origin of enamel sample. The results indicated that initial lesion size affected whether net remineralization or net demineralization occurred during in situ treatment. Samples with an initial range of from 1500 to 2500 (ΔZ) tended more toward demineralization than did samples with ΔZ > 3500. This means that treatment groups must be well-balanced with respect to initial lesion size. Differences in initial demineralization severity between different tooth locations must also be considered so that systematic treatment bias can be avoided. The solution used in the model discussed here is based on a balanced experimental design, which allows this effect to be taken into account in the data analysis.

Enamel Demineralization in situ with Various Frequencies of Carbohydrate Consumption with and without Fluoride Toothpaste

2001 ◽  
Vol 80 (8) ◽  
pp. 1721-1724 ◽  
Author(s):  
M.S. Duggal ◽  
K.J. Toumba ◽  
B.T. Amaechi ◽  
M.B. Kowash ◽  
S.M. Higham
Keyword(s):  
Carbohydrate Consumption ◽  
Fluoride Toothpaste ◽  
Enamel Demineralization

Effect of Fluoride Toothpaste Containing Nano-Sized Sodium Hexametaphosphate on Enamel Remineralization: An in situ Study

2018 ◽  
Vol 53 (3) ◽  
pp. 260-267 ◽  
Author(s):  
Marcelle Danelon ◽  
Luhana G. Garcia ◽  
Juliano P. Pessan ◽  
Amanda Passarinho ◽  
Emerson R. Camargo ◽  
...  
Keyword(s):  
Surface Hardness ◽  
Sodium Hexametaphosphate ◽  
Treatment Groups ◽  
Fluoride Toothpaste ◽  
Integrated Recovery ◽  
Phase Surface ◽  
Double Blinded ◽  
Bovine Enamel ◽  
Caries Lesions

Objective: To evaluate the remineralizing potential of a conventional toothpaste (1,100 ppm F) supplemented with nano-sized sodium hexametaphosphate (HMPnano) in artificial caries lesions in situ. Design: This double-blinded crossed study was performed in 4 phases of 3 days each. Twelve subjects used palatal appliances containing 4 bovine enamel blocks with artificial caries lesions. Volunteers were randomly assigned into the following treatment groups: no F/HMP/HMPnano (Placebo); 1,100 ppm F (1100F); 1100F plus 0.5% micrometric HMP (1100F/HMP) and 1100F plus 0.5% nano-sized HMP (1100F/HMPnano). Volunteers were instructed to brush their natural teeth with the palatal appliances in the mouth for 1 min (3 times/day), so that blocks were treated with natural slurries of toothpastes. After each phase, surface hardness post-remineralization (SH2), integrated recovery of subsurface hardness (ΔIHR), integrated mineral recovery (ΔIMR) and enamel F concentration were determined. Data were submitted to analysis of variance and Student-Newman-Keuls’ test (p < 0.001). Results: Enamel surface became 42% harder when treated with 1100F/HMPnano in comparison with 1100F (p < 0.001). Treatment with 1100F/HMP and 1100F/HMPnano promoted an increase of ∼23 and ∼87%, respectively, in ΔIHR when compared to 1100F (p < 0.001). In addition, ΔIMR for the 1100F/HMPnano was ∼75 and ∼33% higher when compared to 1100F and 1100F/HMP respectively (p < 0.001). Enamel F uptake was similar among all groups except for the placebo (p < 0.001). Conclusion: The addition of 0.5% HMPnano to a conventional fluoride toothpaste was able to promote an additional remineralizing effect of artificial caries lesions.

Effects of soy and bovine milk beverages on enamel mineral content in a randomized, double-blind in situ clinical study

2019 ◽  
Vol 88 ◽  
pp. 103160 ◽  
Author(s):  
Peiyan Shen ◽  
Glenn D. Walker ◽  
Yi Yuan ◽  
Coralie Reynolds ◽  
David P. Stanton ◽  
...  
Keyword(s):  
Clinical Study ◽  
Mineral Content ◽  
Bovine Milk ◽  
Double Blind

Impact of Reducing Water Fluoride on Dental Caries and Fluorosis

2020 ◽  
pp. 002203452097877
Author(s):  
P. James ◽  
M. Harding ◽  
T. Beecher ◽  
D. Browne ◽  
M. Cronin ◽  
...  
Keyword(s):  
Primary Teeth ◽  
Fluoride Concentration ◽  
Permanent Teeth ◽  
Caries Experience ◽  
Caries Prevalence ◽  
Fluoride Toothpaste ◽  
Significant Difference ◽  
Policy Measures ◽  
The Difference ◽  
Water Fluoride

Guidance intended to reduce fluoride toothpaste ingestion in early childhood was introduced in Ireland in 2002. In 2007, water fluoride concentration was adjusted from 0.8–1.0 to 0.6–0.8 ppm. The objective of this study was to determine the difference in caries and fluorosis levels following introduction of these 2 policy measures. A before-and-after study compared caries and fluorosis in random samples of 8-y-olds in Dublin ( n = 707) and Cork-Kerry ( n = 1148) in 2017 with 8-y-olds in Dublin ( n = 679) and Cork-Kerry ( n = 565) in 2002. Dentinal caries experience (primary teeth, d3vcmft(cde)) and fluorosis (permanent teeth, Dean’s index of very mild or higher) were clinically measured. Lifetime exposure to community water fluoridation (CWF) was classified as “full CWF”/“no CWF.” Effect of examination year on caries prevalence and severity and fluorosis prevalence was assessed using multivariate regression adjusting for other explanatory variables. There was little change in commencement of fluoride toothpaste use at ≤24 mo following introduction of toothbrushing guidance. Among children with full CWF, there was no statistically significant difference in caries prevalence or severity between 2017 and 2002. In 2017, caries prevalence was 55% in Dublin (full CWF) and 56% in Cork-Kerry (full CWF), and mean d3vcmft(cde) among children with caries was 3.4 and 3.7, respectively. Caries severity was less in 2017 (mean 4.2) than 2002 (mean 4.9) among children with no CWF ( P = 0.039). The difference in caries severity between children with full CWF and no CWF was less in 2017 than in 2002 (interaction P = 0.013), suggesting a reduced benefit for CWF in 2017. In 2017, fluorosis prevalence was 18% in Dublin (full CWF) and 12% in Cork-Kerry (full CWF). Fluorosis was predominantly “very mild” with no statistically significant difference between 2017 and 2002. CWF at 0.6 to 0.8 ppm is an effective caries-preventive measure. Results suggested low uptake of toothbrushing guidance, a reduced caries-preventive effect for CWF in primary teeth, and no reduction in fluorosis following introduction of the policy measures.

scholarly journals Viability of using enamel and dentin from bovine origin as a substitute for human counterparts in an intraoral erosion model

2010 ◽  
Vol 21 (4) ◽  
pp. 332-336 ◽  
Author(s):  
Cecilia Pedroso Turssi ◽  
Danielle Furtado Messias ◽  
Silmara Milori Corona ◽  
Mônica Campos Serra
Keyword(s):  
Mineral Water ◽  
Real Life ◽  
Dental Erosion ◽  
Human Enamel ◽  
Erosion Models ◽  
Human Counterpart ◽  
Real Life Situation ◽  
Root Dentin ◽  
Bovine Enamel

This study ascertained whether under dental erosion models that closely mimics the real-life situation enamel and root dentin from bovine origin would be reliable substitutes for human counterparts. Through a 2x2 crossover design, in a first trial, 14 volunteers wore a palatal device containing slabs of bovine and human enamel. Half of the participants ingested (4x daily, for 10 days) orange juice first, crossing over to mineral water, while the remainder received the reverse sequence. In a second trial, volunteers wore devices with slabs of bovine and human root dentin. Except for the duration of each intraoral phase, which lasted 2 rather 10 days, the experiment with root dentin run exactly as for enamel. Dental substrates were analyzed for surface microhardness. Two-way ANOVAs (α=0.05) indicated no difference between the microhardness values recorded for human and bovine enamel (p=0.1350), but bovine root dentin had lower microhardness compared to its human counterpart (p=0.0432). While bovine enamel can reliably substitute its human counterpart in in situ dental erosion models, bovine root dentin does not seem to be a viable alternative to the corresponding human tissue.

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