Re- and Demineralization Characteristics of Enamel Depending on Baseline Mineral Loss and Lesion Depth in situ

2016 ◽  
Vol 50 (2) ◽  
pp. 141-150 ◽  
Author(s):  
Richard J. Wierichs ◽  
Julian Lausch ◽  
Hendrik Meyer-Lueckel ◽  
Marcella Esteves-Oliveira

Objectives: The aim of this double-blinded, randomized, cross-over in situ study was to evaluate the re- and demineralization characteristics of sound enamel as well as lowly and highly demineralized caries-like enamel lesions after the application of different fluoride compounds. Methods: In each of three experimental legs of 4 weeks, 21 participants wore intraoral mandibular appliances containing 4 bovine enamel specimens (2 lowly and 2 highly demineralized). Each specimen included one sound enamel and either one lowly demineralized (7 days, pH 4.95) or one highly demineralized (21 days, pH 4.95) lesion, and was positioned 1 mm below the acrylic under a plastic mesh. The three randomly allocated treatments (application only) included the following dentifrices: (1) 1,100 ppm F as NaF, (2) 1,100 ppm F as SnF2 and (3) 0 ppm F (fluoride-free) as negative control. Differences in integrated mineral loss (ΔΔZ) and lesion depth (ΔLD) were calculated between values before and after the in situ period using transversal microradiography. Results: Of the 21 participants, 6 did not complete the study and 2 were excluded due to protocol violation. Irrespectively of the treatment, higher baseline mineral loss and lesion depth led to a less pronounced change in mineral loss and lesion depth. Except for ΔΔZ of the dentifrice with 0 ppm F, sound surfaces showed significantly higher ΔΔZ and ΔLD values compared with lowly and highly demineralized lesions (p < 0.05, t test). Conclusion: Re- and demineralization characteristics of enamel depended directly on baseline mineral loss and lesion depth. Treatment groups should therefore be well balanced with respect to baseline mineral loss and lesion depth.

2018 ◽  
Vol 53 (3) ◽  
pp. 260-267 ◽  
Author(s):  
Marcelle Danelon ◽  
Luhana G. Garcia ◽  
Juliano P. Pessan ◽  
Amanda Passarinho ◽  
Emerson R. Camargo ◽  
...  

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.


2004 ◽  
Vol 83 (1) ◽  
pp. 71-75 ◽  
Author(s):  
A.F. Paes Leme ◽  
R. Dalcico ◽  
C.P.M. Tabchoury ◽  
A.A. Del Bel Cury ◽  
P.L. Rosalen ◽  
...  

Since the effect of the combination of methods of fluoride use on enamel demineralization and on plaque composition is not clearly established, this study examined the effect of the combination of acidulated phosphate fluoride (APF) application and F dentifrice on enamel demineralization and on plaque composition. In this crossover study, 16 volunteers, wearing a palatal appliance containing bovine enamel blocks, were subjected to 4 treatment groups: non-fluoridated dentifrice (PD), FD, APF+PD, and APF+FD. The APF was applied to the enamel before the 14-day experimental period. During the experimental period, test dentifrices were applied 3×/day, and a 20% sucrose solution was applied 4× and 8×/day by being dripped on the blocks. Although APF application was able either to increase F concentration in plaque or to reduce the % of mutans streptococci, its combination with F dentifrice use neither reduced enamel mineral loss nor changed any other measured plaque variable with respect to the FD group alone.


2014 ◽  
Vol 49 (1) ◽  
pp. 56-62 ◽  
Author(s):  
Hendrik Meyer-Lueckel ◽  
Richard J. Wierichs ◽  
Timo Schellwien ◽  
Sebastian Paris

The aim of this double-blind, randomized, cross-over in situ study was to compare the remineralizing effects induced by the application of casein phosphopeptide-stabilized amorphous calcium phosphate complexes (CPP-ACP)-containing cream (without fluoride) after the use of fluoride toothpaste with the prolonged use of fluoride toothpaste on enamel caries lesions in situ. During each of three experimental legs of 4 weeks, 13 participants wore intra-oral mandibular appliances with 8 pre-demineralized bovine enamel specimens in the vestibular flanges mimicking either ‘easily cleanable' or ‘proximal' surfaces (n = 312). The three randomly allocated treatments were as follows: (1) application of CPP-ACP-containing cream (GC Tooth Mouse, non-fluoride) after the use of fluoride toothpaste (1,400 ppm NaF; TM), (2) prolonged application of fluoride toothpaste (1,400 ppm NaF; positive control, PC) and (3) prolonged application of fluoride-free toothpaste (negative control, NC). Additionally, one of each of the two flanges was brushed twice daily with the respective toothpaste. The differences in integrated mineral loss as assessed by transversal microradiography were calculated between values before and after the in situ period. Changes in mineral loss were analysed for those pairs of subgroups differing in only one of the three factors (intervention, brushing and position). The PC treatment induced a significantly higher mineral gain compared with the TM and NC treatments. No significant differences between TM and NC for both positions were observed. In conclusion, the additional use of a CPP-ACP-containing cream seems to be less efficacious in remineralizing caries lesions than the prolonged application of fluoride toothpaste. © 2014 S. Karger AG, Basel


2006 ◽  
Vol 85 (7) ◽  
pp. 617-621 ◽  
Author(s):  
L.K.A. Rodrigues ◽  
M. Nobre dos Santos ◽  
J.D.B. Featherstone

Laser and fluoride treatments have been shown to inhibit enamel demineralization in the laboratory. However, the intra-oral effects of this association have not been tested. This study assessed in situ the effect of a Transversely Excited Atmospheric CO2 laser (λ = 9.6 μm) and the use of pressure fluoridated dentifrice on enamel demineralization. During two 14-day phases, 17 volunteers wore palatal appliances containing human enamel slabs assigned to treatment groups, as follows: (1) non-fluoride dentifrice, (2) CO2 laser irradiation plus non-fluoride dentifrice, (3) fluoride dentifrice, and (4) CO2 laser irradiation plus fluoride dentifrice. A 20% sucrose solution was dripped onto the slabs 8 times per day. The specimens treated with laser and/or fluoridated dentifrice presented a significantly lower mineral loss when compared with those from the non-fluoride dentifrice group. The results suggested that CO2 laser treatment of enamel inhibits demineralization in the human mouth, being more effective when associated with fluoride.


2016 ◽  
Vol 50 (6) ◽  
pp. 571-578 ◽  
Author(s):  
Eliana M. Takeshita ◽  
Marcelle Danelon ◽  
Luciene P. Castro ◽  
Robson F. Cunha ◽  
Alberto C. B. Delbem

Objective: To evaluate the effect of a low-fluoride (F) toothpaste supplemented with sodium trimetaphosphate (TMP) on enamel remineralization in situ. Design: Bovine enamel blocks were selected on the basis of their surface hardness (SH) after caries-like lesions had been induced, and randomly divided into 4 treatment groups, according to the toothpastes used: without F or TMP (placebo); 500 ppm F; 500 ppm F plus 1% TMP; and 1,100 ppm F. The study design was blinded and crossover and performed in 4 phases of 3 days each. Eleven subjects used palatal appliances containing 4 bovine enamel blocks which were treated 3 times per day during 1 min each time, with natural slurries of saliva and toothpaste formed in the oral cavity during toothbrushing. After each phase, the percentages of surface (%SHR) and subsurface hardness recovery (%ΔKHNR) were calculated. F, calcium (Ca), and phosphorus (Pi) contents in enamel were also determined. Data were analyzed by 1-way, repeated-measures ANOVA, followed by the Student-Newman-Keuls test (p < 0.05). Results: Toothpaste with 500 ppm F + TMP and 1,100 ppm F showed similar %SHR and %ΔKHNR as well as enamel F, Ca, and Pi concentrations. Conclusion: The addition of TMP to a low-fluoride toothpaste promoted a similar remineralizing capacity to that of a standard (1,100 ppm F) toothpaste in situ.


2011 ◽  
Vol 6 (3) ◽  
pp. 414-421 ◽  
Author(s):  
Carolina Steiner-Oliveira ◽  
Lidiany Rodrigues ◽  
Iriana Zanin ◽  
Carolina Carvalho ◽  
Regianne Kamiya ◽  
...  

AbstractThe complexity of the oral environment and ethical issues have prompted the development of an in vitro bacterial model to evaluate the effect of frequency of sucrose exposure on dentin caries formation, biofilm composition, and pH changes. In the experiment, dentin specimens (n=45) were randomly divided into four groups: control (C), negative control (0S), 3S (three sucrose baths), and 6S (six sucrose baths). The specimens then were inoculated with Streptococcus mutans and treated according to the protocol described below. Dentin demineralization and lesion depth were assessed by transverse microradiography. Extracellular polysaccharides that formed in the biofilm were analyzed and counts of microorganisms in the carious dentin were measured. After a 7-day period of growth, the biofilm pH was assessed before and after sucrose baths (n=5). The addition of sucrose led to dentin caries development regardless of the number of sucrose baths performed. The number of colony forming units (cfu) from the carious dentin did not differ among the treatment groups, though the extracellular polysaccharides from both 3S and 6S differed from 0S. The pH decreased immediately after the sucrose bath but increased again after 5 min. We demonstrate here that the in vitro microbial model for the study of dentin caries formation is reproducible and able to produce dentin caries, irrespective of the frequency of sucrose exposure.


2014 ◽  
Vol 15 (2) ◽  
pp. 195-201 ◽  
Author(s):  
Carlos Rocha Gomes Torres ◽  
Alessandra Bühler Borges ◽  
Carolina Anne Guimarães ◽  
Eduardo Bresciani ◽  
Carolina Judica Ramos ◽  
...  

ABSTRACT Aim This study evaluated the effect of adding calcium or fluoride to 35% hydrogen peroxide (HP) bleaching gel and the effect of human saliva on the microhardness of sound and demineralized enamel, using an in situ model. Materials and methods Cylindrical bovine enamel specimens (3 × 2 mm) were divided into two groups (n = 30): sound enamel (SE) and demineralized enamel (DE). Each group was divided into three subgroups, according to the bleaching gel: 35% HP; 35% HP + calcium; 35% HP + fluoride. After bleaching therapy, the specimens were fixed to intraoral devices worn by 10 volunteers for 7 days. Surface enamel microhardness (SMH) was measured before and after bleaching procedures, and after 1 and 7 days of saliva exposure. Data were analyzed by Repeated Measures ANOVA (5%). Results The variable time resulted in significant differences for SE and DE groups (p = 0.001). For SE, significantly lower SMH was detected for control at post-bleaching period in comparison to the baseline and after 7 days. For DE, the lowest mean values were obtained before bleaching, and the addition of calcium to the peroxide significantly increased enamel SMH. The exposure to human saliva resulted in increased SMH. Conclusion The addition of potential remineralizing agents into bleaching gels might play an important role in maintaining the microhardness of sound enamel and in inducing remineralization of artificially demineralized enamel right after bleaching, and the remineralizing action of human saliva might minimize the deleterious effects of bleaching gels on enamel. Clinical significance The incorporation of calcium into HP bleaching gel might be beneficial for the initial phases of the bleaching procedure. How to cite this article Borges AB, Guimarães CA, Bresciani E, Ramos CJ, Borges ALS, Torres CRG. Effect of Incorporation of Remineralizing Agents into Bleaching Gels on the Microhardness of Bovine Enamel in situ. J Contemp Dent Pract 2014;15(2):195-201.


2021 ◽  
Vol 62 (1) ◽  
pp. 22-32
Author(s):  
Eduardo Monteiro Toschi ◽  
Eliseu Aldrighi Münchow ◽  
Luísa Weber Mercado ◽  
Rafael Melara ◽  
Sandra Liana Henz

Tooth whitening can be performed at the dental office, at-home or upon the use of OTC (Over-the-Counter) products. Among the latter, there are whitening toothpastes that promise to bleach and to prevent tooth staining. Objectives: (1) to investigate the bleaching and abrasive potential of different whitening dentifrices to enamel; and (2) to evaluate the effect of Oral-B 3D White Perfection® (Oral-B) toothpaste in preventing staining. Materials and Methods: Bovine enamel samples were stained and brushed for 14 days with water (negative control) or with different products: Colgate Total 12® (control), Oral-B, Sensodyne Branqueador Extra Fresh® (Sensodyne), and Colgate Luminous White Advanced® (Colgate). Oral-B was also tested before and after staining. The samples were tested by their color (spectrophotometer) and surface roughness (profilometer). Color change (ΔDE00) was calculated using the CIEDE2000 color system. The data were analyzed using Kruskal-Wallis, SNK, and Mann-Whitney tests (ɑ=5%). Results: The negative control showed the lowest ΔE00 (p


2005 ◽  
Vol 94 (1) ◽  
pp. 44-50 ◽  
Author(s):  
Cecilia C. C. Ribeiro ◽  
Cínthia P. M. Tabchoury ◽  
Altair A. Del Bel Cury ◽  
Livia M. A. Tenuta ◽  
Pedro L. Rosalen ◽  
...  

Sincein vitroand animal studies suggest that the combination of starch with sucrose may be more cariogenic than sucrose alone, the study assessedin situthe effects of this association appliedin vitroon the acidogenicity, biochemical and microbiological composition of dental biofilm, as well as on enamel demineralization. During two phases of 14 d each, fifteen volunteers wore palatal appliances containing blocks of human deciduous enamel, which were extra-orally submitted to four groups of treatments: water (negative control, T1); 2 % starch (T2); 10 % sucrose (T3); and 2 % starch+10 % sucrose (T4). The solutions were dripped onto the blocks eight times per day. The biofilm formed on the blocks was analysed with regard to amylase activity, acidogenicity, and biochemical and microbiological composition. Demineralization was determined on enamel by cross-sectional microhardness. The greatest mineral loss was observed for the association starch+sucrose (P<0·05). Also, this association resulted in the highest lactobacillus count in the biofilm formed (P<0·05). In conclusion, the findings suggest that a small amount of added starch increases the cariogenic potential of sucrose.


2006 ◽  
Vol 85 (7) ◽  
pp. 612-616 ◽  
Author(s):  
A.T. Hara ◽  
M. Ando ◽  
C. González-Cabezas ◽  
J.A. Cury ◽  
M.C. Serra ◽  
...  

The acquired dental pellicle helps prevent erosion, but the protection level is unknown. This in situ study tested whether a two-hour pellicle protects against different erosive challenges by orange juice. Subjects wore palatal appliances loaded with either enamel or dentin specimens. Pellicle was allowed to form, or not (control), on the surfaces of the specimens intra-orally for 2 hrs before the erosive challenges of 0 (control), 10, 20, and 30 minutes’ duration. Specimens were randomly removed from the appliances after each challenge. Percentage of surface microhardness change (%SMC) was determined for the enamel specimens, and that of mineral loss and lesion depth for the dentin specimens. Enamel specimens with the pellicle showed a significantly lower %SMC, only after the 10-minute challenge. No protection was found for dentin. It was concluded that the acquired pellicle reduced dental erosion, but that this effect was limited to the less severe erosive challenge on enamel surfaces.


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