Acidulated Phosphate Fluoride Gel Research Articles

Re-Mineralization Capability of Two Natural Nano-Plant Extracts on Early Enamel Caries using Diode Laser

Background: To investigate diode laser application and two natural nano-plant extracts effect on the re-mineralization and surface micro-hardness of early enamel carious lesions. Materials and Methods: Eighty enamel specimens were selected and prepared then divided into eight groups (10 specimens per group), according to diode laser irradiation, two nano-plant extracts (garlic and clove nano-plant extracts) and acidulated phosphate fluoride (APF) gel, that were applied to demineralized enamel surfaces as follows; Group A; garlic nano-plant extract, Group B; clove nano-plant extract, Group C; application of APF gel, Group D; garlic nano-plant extract + diode laser, Group E; clove nano-plant extract + diode laser, Group F; application of APF gel + diode laser, Group G; diode laser, Group H; early enamel caries (control). Specimens were examined for their content of Ca, P, and F ions and their surface Vickers micro-hardness. The tests used for the statistical analysis were one-way ANOVA followed by Tukey's (honestly significant difference) post hoc tests. Results: No statistically significant difference was detected between the tested groups for Ca and P content, while Group A recording the highest mean value. Group C recorded the highest F ion content values, while G and H groups recorded the least values. Group F recorded the highest significant micro-hardness values, while Group H recorded the least values. Conclusions: Garlic and clove nano-plant extracts may present a promising enamel re-mineralizing agents. Combination of both nano-extracts with diode laser application had a positive influence on enamel chemistry and micro-hardness.

Fluoride Formed on Enamel by Fluoride Varnish or Gel Application: A Randomized Controlled Clinical Trial

Although fluoride varnish (FV) and acidulated phosphate fluoride gel (APF-gel) are considered clinically effective to reduce caries, in vitro studies have shown that FV reacts slowly with enamel because most NaF present in the formulation is not solubilized in the FV. Therefore, we conducted a clinical study to evaluate if the time that FV remains on dental surfaces could overcome its slower chemical reactivity when compared with APF-gel. Sixty-eight volunteers were randomly allocated into 4 groups: negative control (Control, no treatment), APF-gel application (1.23% F applied for 4 min), and FV application (Duraphat®, 2.26% F) for 4 h (FV-4h) or 24 h (FV-24 h). To evaluate fluoride formed and retained on enamel, acid biopsies were made on the buccal surfaces of the maxillary central incisors before, at the end of the application of fluoride products (immediately after gel application, or after 4 or 24 h of varnish application), and after 7 and 28 days. Fluoride concentration in dental biofilm was also analyzed before and up to 28 days after initial application. The data were analyzed by 2-way ANOVA, considering treatment and time as factors. The APF-gel and FV-24h groups formed greater fluoride concentration on enamel than the FV-4h and the control group at the end of application (p = 0.0001), with no difference from each other (p = 0.99). The groups did not differ regarding fluoride in biofilm fluid (p = 0.73) and solids (p = 0.40). In conclusion, FV needs to remain in contact with the teeth for prolonged times (>4 h) to reach the same reactivity obtained by a 4-min application of APF-gel.

Biomineralization induced by chitosan and collagen-based materials with fluoride for dentin coverage: Chemical and morphological analysis.

The prevention and treatment of erosive tooth wear are becoming increasingly important due to its increasing prevalence. The use of natural solutions to modify dental surfaces has become an area of research. Organic materials such as chitosan and hydrolyzed collagen may be a promising option to treat dentin. This in vitro study aimed to evaluate the influence of chitosan or hydrolyzed collagen, alone or combined with acidulated phosphate fluoride (APF) gel, on the composition and morphology of dentin after erosion. Bovine dentin samples were prepared (n= 84) and treated with artificial saliva (AS, negative control); APF gel (F, positive control); chitosan solution (Chi); hydrolyzed collagen solution (Col); fluoride/chitosan composition (F_Chi); and fluoride/hydrolyzed collagen composition (F_Col). Erosive cycles (six cycles of immersion in orange juice for 1min, followed by immersion in AS for 1 hr) were performed. The materials were characterized by their morphology, composition, and particle size distribution. Micro-energy dispersive X-ray fluorescence spectroscopy and scanning electron were used to evaluate the dentin's inorganic chemical composition and morphology. The F_Col and F groups had a reduction in calcium loss by 17 and 26%, respectively (p<.001). Both of these groups still had a covering layer of agglomerates at the dentin surface after the erosive cycles. The fluoridated chitosan or collagen solutions improved the dentin resistance to erosion as a novel hybrid-fluoride-based material approach to provide surface protection from erosion.

Effect of Er:YAG Laser Irradiation and Acidulated Phosphate Fluoride Therapy on Re-Mineralization of White Spot Lesions.

Statement of the Problem: Studies on the efficacy of erbium laser for enhancement of enamel resistance to acid attacks and its effects on fluoride uptake by the enamel are limited.Purpose: This study sought to assess and compare the effects of erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation and application of acidulated phosphate fluoride (APF) gel (alone and in combination) on remineralization of artificial white spot lesions (WSLs).Materials and Method: This in vitro, experimental study evaluated 90 buccal and lingual slabs of extracted human premolars. The specimens underwent pH cycling to induce WSLs. They were then randomly divided into 6 groups of caries-free positive control (c+), negative control with WSLs (ws), 1.23% APF gel applied on the enamel (F), Er:YAG laser irradiation (80 mJ, 10 Hz, and 8 J/cm2) of enamel (L), APF gel application followed by laser irradiation (FL), and laser irradiation followed by fluoride gel application (LF). The fluoride ion content of specimens was measured before and after the intervention using a potentiometer. Data were analyzed by ANOVA (p< 0.05).Results: APF gel application before/after laser irradiation maximally increased the fluoride uptake by the enamel (p= 0.000). Application of APF gel in group F and laser irradiation in group L increased fluoride uptake by the enamel, compared with groups 1 and 2 (p= 0.000). Laser- treated (L) and APF-treated (F) groups had no significant difference in this respect (p= 0.945). Maximum fluoride concentration was noted in combined laser and fluoride groups (FL=332.07ppm and LF=341.27ppm) with no significant difference between the two (p= 1.000).Conclusion: Er:YAG laser irradiation changes the chemical composition of enamel and probably promote its remineralization, especially when combined with APF gel application, which highlights its cariostatic potential.

Cytotoxicity, genotoxicity, and cellular metal accumulation caused by professionally applied fluoride products in patients with fixed orthodontic appliances: A randomized clinical trial

Corrosion of metal orthodontic appliances caused by professional fluoride products has been recently concerned. Therefore, the objective of this study was to evaluate the cytotoxic and genotoxic effect of these products on buccal mucosal cells from patients wearing fixed orthodontic appliances. A total of 44 patients, aged 12 to 35 years, who began orthodontic treatment with fixed appliances were included in this single-center, prospective, randomized clinical trial. Patients were randomly allocated into 4 parallel groups according to the type of professional fluoride treatment applied after placing the appliances: acidulated phosphate fluoride gel (APF); neutral fluoride gel (NGel); fluoride varnish (FVa); and without fluoride treatment (control). Buccal cells were collected before treatment (T1) and 3 months after appliance placement (T2). The cells were assayed for cell viability and underwent Papanicolaou staining. Cells with micronuclei and degenerative nuclear alterations were scored using a light microscope. Cell metal content was quantified by inductively coupled plasma-mass spectrometry. The data were analyzed with the Kruskal-Wallis test. The intracellular nickel content in the APF group significantly increased (P < 0.05), whereas that of the control, NGel, and FVa groups did not. The changes in chromium concentration in all groups were not significantly different compared with control. Use of APF resulted in a significantly higher decrease in cell viability and increase in morphologic signs of cell death compared with control (P < 0.05). The change in frequency of micronucleated cells was not significantly different from that in the control group. Applying APF gel on fixed orthodontic appliances increased the cell metal content and decreased cell viability; however, genotoxic effects were absent. FVa and NGel are suggested as the products of choice to use during orthodontic treatment.

Assessment of the preventive effects of Nd:YAG laser associated with fluoride on enamel caries using optical coherence tomography and FTIR spectroscopy

ObjectiveThis in vitro study characterized and monitored, by Optical Coherence Tomography (OCT) and Fourier Transformed Infrared Spectroscopy (FTIR), the effects of the association of acidulated phosphate fluoride gel (APF-gel) and Nd:YAG (neodymiun:yttrium-aluminum-garnet) laser, as sequencial treatments, in the prevention of incipient enamel caries lesions.Methods120 human enamel samples were randomized into 3 groups (n = 40): APF-gel (1.23% F-, 4 min.); Laser+APF (Nd:YAG laser irradiation—0.6W, 84.9J/cm2, 10Hz, followed by APF-gel); and APF+Laser (APF-gel followed by laser irradiation). The samples were subjected to a 15-day pH-cycling, evaluated by OCT (quantification of optical attenuation coefficient–OAC) and FTIR (analysis of carbonate and phosphate content) before treatments, after treatments, and on the 5th, 10th and 15th days of pH-cycling. The statistical analysis was performed (α = 5%).ResultsThe Optical Attenuation Coefficient (OAC) assessed by OCT increases with the progression of demineralization, and the Laser+APF presented the highest values of OAC in 10th and 15th days of pH-cycling. Nd:YAG decreased the carbonate content after treatment regardless of the application order of the APF-gel, while APF-gel did not interfere in the composition of enamel. The carbonate content was also changed in the first 5 days of the pH-cycling in all groups.ConclusionNd:YAG laser irradiation before or after the application of APF-gel did not influence the appearance of incipient caries lesions, showing no synergistic effect. Regardless of the application order of the APF-gel, laser irradiation reduces the carbonate content of the enamel, which also changes during the demineralization process. However, irradiation before the application of APF-gel increased the speed of progression of the lesions, which positively impacts public health as it can prevent caries disease, even in high risk individuals. OCT and FTIR are suitable for assessing this effect.

Exposure to the oral environment enhances the corrosion of metal orthodontic appliances caused by fluoride-containing products: Cytotoxicity, metal ion release, and surface roughness

This study aimed to evaluate the metal ion release, cytotoxicity, and surface roughness of clinically used metal orthodontic appliances after immersion in different fluoride product solutions compared with those of new appliances. Used fixed appliances were debonded from 36 patients after their treatment was done. New appliances were as-received. Each used and new group comprised 36 sets of 20 brackets and 4 tubes that were divided into 3 groups by archwire type; stainless steel, nickel-titanium, and beta-titanium. The samples in each group were divided into 3 subgroups and immersed in solutions of fluoride toothpaste, 1.23% acidulated phosphate fluoride, or artificial saliva without fluoride as a control group. The immersion times were estimated from the recommended time for using each fluoride product for 3months. The samples were then immersed in Dulbecco's Modified Eagle's Medium for 7days. The cytotoxicity test was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay using primary gingival fibroblasts. Chromium, nickel, and iron ion release were detected using inductively coupled plasma mass spectroscopy. The surface roughness of the brackets and wires was measured by a scanning electron microscope and a noncontact optical 3-dimensional surface characterization and roughness measuring device. The data were analyzed using the paired t test and 2-way analysis of variance. Used brackets demonstrated a significantly higher ion release, surface roughness, and cytotoxicity than the new brackets. Acidulated phosphate fluoride significantly increased the ion release and surface roughness; however, it significantly decreased cell viability, especially in the titanium molybdenum subgroup. Used brackets were significantly prone to further corrosion. Acidulated phosphate fluoride gel should not be used in orthodontic patients with fixed metal appliances.

Comparison of the Fluoride Release of Silver Diamine Fluoride, Fluoride Varnish, Acidulated Phosphate Fluoride Gel on Extracted Teeth over Various Time Intervals in Artificial Saliva

Silver Diamine Fluoride (SDF) has been documented to effectively arrest dental caries and reduce dental hypersensitivity. SDF promotes remineralization and harden the carious lesion. SDF increases fluoride concentration in saliva and increase the bioavailability of fluoride in saliva. After SDF application, fluoride ion promotes remineralization and silver ion is available for antimicrobial action.&#x0D; Aim: The study aims to determine and compare the amount of fluoride released from various fluoride releasing materials in artificial saliva after 24 hours, 7th day and 14th day of the study.&#x0D; Materials and Methods: 96 premolars free of any caries, fractures, or any other defects were sterilized in 10% formalin for 2 weeks. Then they were rinsed in tap water to remove any fixative from its surface and then stored in deionised distilled water for a period of 30 days prior to testing. Tooth samples were divided into four groups- Group 1: 38% SDF, Group 2: 1.23% APF gel, Group 3: Fluoride varnish and Group 4: Control. All the teeth specimens were blot dried and subjected to their respective material. Fluoride release was analysed using a Fluoride ion-selective electrode after 24 hours, 7days and 14 days of suspension in artificial saliva.&#x0D; Results: Mann-Whitney U Test for inter-group comparison was used for statistical evaluation. 24 Hours fluoride release: The maximum amount of fluoride was released from Fluoride Varnish followed by SDF then APF Gel and least by artificial saliva alone (control) (p&lt;0.001). 7th Day fluoride release: The maximum amount of fluoride was released from SDF followed by Fluoride Varnish then APF Gel and least by artificial saliva alone (control) (p&lt;0.001). 14th Day fluoride release: The maximum amount of fluoride was released from Fluoride Varnish followed by SDF then APF Gel and least by artificial saliva alone (control) (p&lt;0.001).

THE EFFECT OF SURFACE COATING AGENT ON THE SURFACE ROUGHNESS OF RESTORATIVE MATERIALS EXPOSED TO ACIDULATED PHOSPHATE FLUORIDE

Aim: The aim of the study was to assess the surface roughness of six different restorative materials when they were covered with surface coating agent prior to 1.23% acidulated phosphate fluoride gel application. Materials and methods: Six restorative materials (Fuji IX, Amalgomer CR, Dyract XP, Beautifil II, ACTIVA, Filtek Z250) were used in this study. 28 specimens were prepared from each material and randomly divided into 4 groups (n=7) according to surface treatment regimens. Group C: control, no application, Group F: only acidulated phosphate fluoride gel application, Group S: only surface coating agent application, Group SF: surface coating agent prior to the acidulated phosphate fluoride gel application. The surface roughness values for all specimens were measured using profilometer. The results were statistically analyzed using analysis of variance (ANOVA), Newman Keuls and Tukey’s tests (p<0.05). Results: There were no statistically significant differences in surface roughness between group C and F for all analyzed materials, except for Amalgomer CR (p>0.05). The group C of Amalgomer CR showed higher surface roughness values than that of the group F (p=0.001). Group S produced significantly smoother surfaces than the group C for all restorative materials, except Dyract XP (p=0.001). Conclusion: 1.23% acidulated phosphate fluoride gel application did not promote a significant increase on the surface roughness of restorative materials whether or not surface coated. However, surface coating was found to produce smoother surfaces. Keywords: Fluoride gel, Glass ionomer cement, Surface roughness ASİDÜLE FOSFAT FLUORİD UYGULANAN RESTORATİF MATERYALLERİN YÜZEY PÜRÜZLÜLÜĞÜNE YÜZEY ÖRTÜCÜ AJANININ ETKİSİ ÖZ: Amaç: Bu çalışmanın amacı, %1,23 asidüle fosfat fluorid jel uygulamasından önce yüzey örtücü ajanı ile kaplanan altı farklı restoratif materyalin yüzey pürüzlülüğünün değerlendirilmesidir. Gereç ve yöntem: Çalışmada altı restoratif materyal (Fuji IX, Amalgomer CR, Dyract XP, Beautifil II, ACTIVA, Filtek Z250) kullanıldı. Her bir materyalden 28 örnek hazırlandı ve yüzeye yapılan uygulamalara göre rastgele 4 gruba ayrıldı (n=7). Grup K: kontrol, herhangi bir uygulama yapılmadı, Grup F: sadece asidüle fosfat fluorid jel uygulandı, Grup S: sadece yüzey örtücü ajan uygulandı, Grup SF: asidüle fosfat fluorid jel uygulanmadan önce yüzey örtücü ajan uygulandı. Tüm örneklerin yüzey pürüzlülüğü değerleri profilometre ile belirlendi. Sonuçların analizi varyans analizi (ANOVA), Newman Keuls ve Tukey testi ile yapıldı (p<0.05). Bulgular: Amalgomer CR dışındaki materyallerde, grup K ve grup F arasında yüzey pürüzülülüğü açısından istatistiksel olarak anlamlı farklılık görülmemiştir (p>0,05). Amalgomer CR’nin K grubu, F grubuna göre daha yüksek yüzey pürüzülülük değeri vermiştir (p=0,001). Dyract XP dışındaki tüm restoratif materyallerde grup S, grup K’ya göre anlamlı derecede daha pürüzsüz yüzey değeri göstermiştir (p=0,001). Sonuç: %1,23 asidüle fosfat fluorid jel uygulaması, yüzey örtücü uygulanmış ve uygulanmamış restoratif materyallerin yüzey pürüzlüğünde önemli bir artış sağlamamıştır. Ancak, yüzey örtücü uygulaması, materyallerin yüzey pürüzlülüğünü azaltmıştır. Anahtar kelimeler: Fluorid jel, Cam iyonomer siman, Yüzey pürüzlülüğü

The effects of combining erbium, chromium: Yttrium-scandium-gallium-garnet laser irradiation with fluoride application in controlling the progression of enamel erosion

ObjectiveIncreasing enamel resistance to acid may be useful for preventing cavitation and could reduce changes in the enamel’s microhardness. Topical fluoride application and laser irradiation promote acid resistance of dental substrates. The aim of the study was to assess the efficacy of erbium, chromium: yttrium-scandium-gallium-garnet laser irradiation in combination with fluoride application to control enamel erosion. DesignSixty human premolar specimens were prepared (N = 60) and were randomly assigned to 5 groups, twelve specimens in each group (n = 12/group) according to surface treatment. The groups were as follows: group 1 (C): control with no treatment; group 2 (F): application of 1.23% acidulated phosphate fluoride gel alone; group 3 (L): laser irradiation alone; group 4 (F+L): acidulated phosphate fluoride gel followed by laser irradiation; group 5 (L+F): laser irradiation followed by acidulated phosphate fluoride gel. All the specimens were eroded 10 min in citric acid. Baseline measurements were performed using a Vickers microhardness tester before surface treatment. Subsequently, all specimens were subjected to a 60 min erosion-remineralization cycle for five days followed by measurements of the final surface microhardness. Statistical comparisons were performed by a one-way analysis of variance and Tukey’s post hoc analysis. ResultsThe control, laser, and fluoride + laser groups showed a statistically significant decrease in microhardness values between baseline and post-erosion measurements (P < 0.05), indicating that these treatments could not prevent erosion progression. However, the fluoride and laser + fluoride groups showed a significant increase in microhardness values compared to baseline. ConclusionsOur results suggest that compared to that of the control group, acidulated phosphate fluoride application as well as laser irradiation prior to fluoride application increased enamel surface microhardness and prevented the progression of enamel erosion.

Verification of antibacterial activity to enamel surfaces of new type of surface coating

Abstract Objective Prevention is difficult to decrease dental caries only via the partial application of fluoride. The GC Co. has developed a coating material adhesive containing fluoride and zinc. It is thought that this zinc has an effect which prevents dental caries. The aim of this study was to evaluate the influence of the Caredyne Shield® (CS) on biofilm generation by S. mutans, as compared to an acidulated phosphate fluoride (APF) gel. Materials and methods We performed the comparative study of the biofilm inhibitory effect which used the enamel of bovine teeth. Specimens were separated into a control group, an APF gel group, and a CS group. Biofilms were generated by adherent S. mutans. We observed the antibacterial weigh by the creation state of Biofilms. Results Significant difference was observed in the number of bacterial colonies formed after 24 h, the number of bacterial colonies formed from detached S. mutans from the CS-treated experimental group were fewer in number than in the other group (p Conclusion We showed in this study the efficacy of CS in controlling the formation of biofilm. From such a result, we conclude that CS is a novel anticaries agent.

Efficacy of 1.23% acidulated phosphate fluoride gel on non-cavitated enamel lesions: a randomized clinical trial

A randomized controlled parallel clinical trial was conducted to evaluate the efficacy of the association of 1.23% topical professional acidulated phosphate fluoride (APF) gel with oral hygiene and dietary instructions on the arrest of active non-cavitated lesions in permanent, mixed, and temporary dentition in children between 3 and 12 years of age. Ninety-eight caries-active children were randomly divided into two groups: a fluoride gel group (n = 49) and a non-fluoridated gel group (n = 49). Each group received up to eight weekly applications of gel, weekly professional toothbrushing with oral hygiene instructions and dietary counselling. Caries lesions were assessed qualitatively through visual-tactile criteria performed in three stages: initial, intermediate, and final. Regression models were applied to identify risk indicators for caries control. Between-group comparison regarding the time taken to arrest the lesions was performed using Chi-squared and Fisher's exact tests. Seventeen children did not receive the allocated intervention, and one was lost to follow-up (n = 80). There was no difference between the control and placebo groups regarding the time to the arrest of the lesion (p >.05). The treatments showed similar results without significant statistical difference (p = 0.33; 95%CI: 0.32-1.48). No adverse effects were observed. It can be concluded that no additional effect of the association of 1.23% APF gel with oral hygiene using fluoride dentifrice and dietary instructions on the arrest of active non-cavitated lesions could be established. We can also confirm the importance of toothbrushing frequency and, consequently, the visible plaque reduction in the control of caries activity. RBR-37V5S3.

The color improvement of postdebonding white spot lesions after fluoride and casein phosphopeptide- amorphous calcium phosphate application.

White spots are common side effects of orthodontic treatment, and their presence after debonding appears unesthetic. This study aimed to quantify and compare the visual improvement in postdebonding white spot lesions following fluoride and casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) application. The sample included 42 upper premolars extracted for orthodontic reasons. Universal premolar brackets were bonded to the facial surfaces of the teeth that were exposed to a demineralization solution to create artificial white spot lesions, after which the brackets were debonded. The specimens were randomly allocated to three treatment groups (n = 14, each): acidulated phosphate fluoride (APF) gel application group; CPP–ACP paste application group; and control group. pH cycling was conducted to all groups for 14 days. Quantitative measurements were carried out using a spectrophotometer at the following times: before and after the white spot lesions artificially formed and after treating them. All groups showed significant differences in color change before and after treatment. However, there was no significant difference in the color improvement between the APF gel and CPP–ACP paste application groups. Although CPP–ACP application improved the color of the white spot lesions, it did not differ significantly from that of fluoride application.

The effect of Remin Pro on the microhardness of initial enamel lesions in primary teeth

Remineralization is currently considered a treatment option for many clinicians. The present study was conducted to compare the effect of three remineralizing agents on microhardness of initial caries lesions in primary teeth. In this in vitro study, 96 enamel samples were prepared. Microhardness was first measured for all the samples using the Vickers microhardness test. After developing the initial caries lesions, the microhardness of all the demineralized samples was measured, and the samples were then divided into four groups (n = 24). Casein phosphopeptide-amorphous calcium phosphate in Group 1, Remin Pro in Group 2, and acidulated phosphate fluoride gel in Group 3 were placed on the samples for 4 min. The control group received no treatments. The microhardness of the samples was measured again following a pH cycle of 5 days. The data were analyzed by ANOVA and the post hoc test at the significance level of P < 0.05. The mean microhardness reduced significantly in all the groups following the development of initial caries lesions and after the pH cycle of 3 days (P < 0.001). After the remineralization and pH cycle of 5 days, the mean microhardness was significantly lower in the control group compared to the other three groups (P < 0.001) and had increased in the three treated groups. The microhardness recovery rate also increased in the treated groups compared to the control group, but no significant differences were observed between the three groups themselves (P > 0.05). Remin Pro can be used as an effective substance for preventing tooth caries in children.

The effect of fluoride gel on tensile properties, surface morphology and chemical composition of two types of orthodontic wires (an in-vitro study).

OBJECTIVE:Stainless steel and nickel-titanium wires are commonly used in fixed orthodontic appliances. Orthodontists often prescribe fluoride gel to avoid demineralization of teeth. This study investigated the effect of acidulated phosphate fluoride gel on the tensile properties, surface morphology and surface chemical composition of stainless steel and nickel-titanium wires.METHODS:Forty samples of stainless steel and nickel-titanium wires were examined, twenty for each type. Each wire type was divided into four subgroups. The first subgroup was not immersed in fluoride gel and considered as control, while the other three subgroups were immersed in 10 mL of fluoride gel for different periods of time. Then, the wires were removed from the gel, rinsed in a distilled water and left to dry. The ultimate tensile force of each wire was measured using a tensile testing machine. Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) were used to examine the control and 24 h immersed subgroups.RESULTS:One-way analysis of variance ANOVA showed that there were no significant differences in the ultimate tensile forces between control and fluoride-treated subgroups (P = 0.172 for SS wires and P = 0.672 for NiTi wires). However, changes in the surface morphology and elemental composition of wires were shown by the SEM and EDX.CONCLUSIONS:Although immersion of stainless steel and nickel-titanium wires in the fluoride gel did not affect their tensile properties, however, surface deterioration was evident. So, further investigations are recommended to study the effect of these changes on the oral health of patients.

Evaluation of shear bond strength of brackets bonded to fluoride-treated enamel surfaces: An in vitro study

Enamel decalcification is a well-recognized problem associated with orthodontic treatment with fixed multibanded appliances. Several methods have been proposed to minimize the incidence and severity of white spot decalcification around brackets. The present study is concerned with the evaluation of the effect of different topical fluoride gels, applied before and after etching on the shear bond strength of directly bonded orthodontic brackets. The sample consisted of (70) human upper first premolars distributed to (7) groups: group A served as a control; groups B1, C1, andDl received, for (4) minutes prior to etching, a topical application of neutral sodium fluoride gel (1.1%), sodium monofluorophosphate gel (1.2%), and acidulated phosphate fluoride gel (1.23%) respectively. Groups B2, C2, and D2, on the other hand, were treated, for (4) minutes after etching, with topical application of neutral sodium fluoride gel (1.1%), sodium monofluorophosphate fluoride gel (1.2%), and acidulated phosphate fluoride gel (1.23%) respectively. The brackets were loaded under shear to failure using Universal Compression Machine Apparatus. The shear strengths were recorded in Megapascals. The results of the present study showed that the application of fluoride gels for (4) minutes before and after etching did not alter the shear bond strengths of directly bonded orthodontic brackets, when compared with the control group, for all groups except for group D2 in which the topical application of acidulated phosphate fluoride gel for (4) minutes after etching has resulted in a significant reduction in shear bond strength and severity of white spot decalcification around brackets.

Caries-preventive effect of topical APF gel with three different frequencies of application in 9-11 years old school children in Ninevah

This is the first study carried out in Iraq that aimed at evaluating the effect on dental caries of Acidulated Phosphate Fluoride (APF) gel applied topically with different frequencies (once per year vs. twice per year vs. four times a year). A sample of (235) school children [116 (49.36%) males and 119 (50.64%) females) initially in the fourth grade (aged 9-11 years) were collected from (4) primary schools in Mosul city Centre. The children were allocated randomly to (3) experimental groups and one control group. The first group received (0.49%) APF gel four times a year for (4) minutes. The second group received (0.4%) APF gel once per year for (4) minutes; whereas the third group received (0.4%) APF gel twice per year for (4) minutes. Two examinations were done using DMFT and DMIFS indices: one before fluoride application and the other after one year. The results showed a reduction in dental caries (with respect to DMFT index, and in comparison with the control group) of (112.8%) for the first group,(35.9%) for the second group, and (80.4%) regarding the third group. With respect to DMFS index, and in comparison with the control group, the reduction in dental caries was (97.3%),(32.8%), and (72.6%), respectively. The best benefit from using topically applied APF gel was, therefore, achieved from applying (0.4%) gel four times a year for (4) minutes.

Does fluoride reduce the mineral loss of gamma‐irradiated primary teeth?—In vitro study

AbstractBackgroundGamma radiation turns the primary enamel more susceptible to demineralization.AimTo investigate if the fluoride dentifrice combined with acidulated phosphate fluoride gel (APF‐gel) inhibits the progression of mineral loss of gamma‐irradiated primary enamel.DesignSpecimens of demineralized primary enamel were randomized into eight groups (n = 13): Non‐irradiated + Non‐fluoride dentifrice (G1); Non‐irradiated + Fluoridated dentifrice (G2); Non‐irradiated + APF‐gel + Non‐fluoridated dentifrice (G3); Non‐irradiated + APF‐gel + Fluoridated dentifrice (G4); Irradiated + Non‐fluoridated dentifrice (G5); Irradiated + Fluoridated dentifrice (G6); Irradiated + APF‐gel + Non‐fluoridated dentifrice (G7); and Irradiated + APF‐gel + Fluoridated dentifrice (G8). Specimens of irradiated groups were submitted to 3060 cGy radiation dose. After APF‐gel treatment, specimens were submitted to a pH cycling, with the respective dentifrice exposure, twice daily. The microhardness and polarized light microscopy analyses were performed to quantitatively and qualitatively assess the enamel mineral loss, respectively. Quantitative data of mineral loss were compared using the two‐way ANOVA, followed by the Tukey test.ResultsFluoride dentifrice alone, APF‐gel application alone, and their combination were not effective in inhibiting mineral loss of irradiated primary enamel.ConclusionThe combination of fluoride dentifrice and APF‐gel was not effective in inhibiting the progression of mineral loss of gamma‐irradiated primary teeth.

Time-dependent effects after enamel fluoride application on an acid etching system in orthodontic bracket bonding.

This study investigated the effectiveness of acid etching and bond strength in an orthodontic bonding system in accordance with various time periods after 1.23% acidulated phosphate fluoride (APF) gel applications. APF gel was applied on the enamel surface of bovine teeth, which were assigned to group F0. The tooth specimens were then immersed in distilled water for 1 (F1), 7 (F7), 14 (F14), 21 (F21) and 28 (F28) days. A group without fluoride pretreatment was a control group. All groups were etched with 35% phosphoric acid and evaluated using a surface hardness tester and scanning electron microscope (SEM). A shear bond strength (SBS) test was performed using a universal testing machine, and the bond failure modes were also examined. After the 1.23% APF gel treatment, the hardness of the acid-etched enamel surface decreased as the immersion period increased. SEM images of the test groups showed etched patterns similar to control group as the immersion period increased. The SBS increased with increasing immersion period, whereas group F21 was not significantly different from the control group. Relatively high adhesive remnant index scores were identified as the ageing period increased. The present study indicated that in order to obtain suitable bond strength, it is recommended to use an acid etching-based bonding system for the fixation of orthodontic appliances on the enamel surface 21days after the use of APF gel. Fluoride pre-treatment interferes with the acid etching effects on enamel, causing a reduction in the bond strength with orthodontic brackets.

Fluoride Release and Recharge Properties of Several Fluoride-Containing Restorative Materials

The aim of the study is to compare the fluoride release and recharge properties of glass ionomer cements and ‘alkasite’.&lt;br/&gt;Specimens of two glass ionomer cements (Fuji Ⅸ GP and Riva Self Cure), ‘alkasite’ restorative material (Cention N) and composite resin (Filtek&lt;sup&gt;TM&lt;/sup&gt; Z350XT) were prepared. The fluoride release of each specimen was measured for 28 days. Thereafter, 1.23% acidulated phosphate fluoride (APF) gel was applied to experimental groups. No treatment was performed on control groups. The fluoride release was measured for additional 7 days to evaluate the fluoride recharge properties of each materials.&lt;br/&gt;The fluoride release was highest in Riva Self Cure, followed by Fuji Ⅸ GP, Cention N (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Fluoride release of Cention N was measured to be approximately 49% of Fuji Ⅸ GP’s. After the application of 1.23% APF gel, increases in fluoride release were observed in Riva Self Cure, Fuji Ⅸ GP and Cention N (&lt;i&gt;p&lt;/i&gt; &lt; 0.05). Fluoride recharge was observed in Cention N as well as in glass ionomer cements. Further studies are required to evaluate the anti-cariogenic properties of Cention N at clinical conditions.