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Clinical assessment of two types of adhesive (fifth & sixth generation) on fissure sealant of saliva contaminated enamel
Karami Nogourani M.,Khadem Abbakhshani P.,Jadidi Z.,Amirpoor G.
Journal of Dental Medicine , 2009,
Abstract: "nBackground and Aim: Since the clinical studies conducted to explore the effect of bonding agents on the success of fissure sealant are limited in number, the present study was conducted to compare the effects of two bonding agents on the success of fissure sealant of the saliva- contaminated teeth. "nMaterials and Methods: In this study, 63 teeth of 35 students aged 6-8 with healthy and newly-erupted upper jaw molar teeth, were selected and divided into two groups. In one group, single-bond and In the other, SE bond were used. As the teeth were newly erupted and the distopalatal area being in contact with the gingival sulcus and this fact that, this area was impossible to isolate, the distal sulcus of the contaminated teeth and the mesial area capable of adequate isolation were assumed isolated. For each group, after etching, the teeth on one side were treated with a sealant and the teeth on the other side were first bonded and then treated with the sealant. Hence, four groups were formed: bonded/isolated, bonded/contaminated, controlled/isolated and controlled/contaminated for any bonding agent. The results of the treatment were assessed in terms of the success and failure and then analyzed using Mc Nemar, and Chi-square tests and Cochran. "nResults: The results of the study indicated that:1. Saliva contamination caused a significant increase in sealant failures(p<0.05).2. Use of the two bonding agents significantly increased the success of the sealant(p<0.05).3. Use of the two bonding agents significantly increased the success of the fissure sealant on the saliva-contaminated teeth, even more than when the teeth had been isolated and with only fissure sealant(p<0.05). 4. For the contaminated enamel, the results of SE bond were better than those of the single bond (p<0.05). However, in isolated condition the results of using single bond were better (p<0.05). "nConclusion: The results of the study supported the use of these two bonding agents in the treatment of fissure sealants under both isolated and contaminated conditions. Further, more SE bond seemed to be less sensitive to saliva contamination.
Bond strength of a pit-and-fissure sealant associated to etch-and-rinse and self-etching adhesive systems to saliva-contaminated enamel: individual vs. simultaneous light curing
Gomes-Silva, Jaciara Miranda;Torres, Carolina Paes;Contente, Marta Maria Martins Giamatei;Oliveira, Maria Angélica Hueb de Menezes;Palma-Dibb, Regina Guenka;Borsatto, Maria Cristina;
Brazilian Dental Journal , 2008, DOI: 10.1590/S0103-64402008000400010
Abstract: this study evaluated in vitro the shear bond strength (sbs) of a resin-based pit-and-fissure sealant [fluroshield (f), dentsply/caulk] associated with either an etch-and-rinse [adper single bond 2 (sb), 3m/espe] or a self-etching adhesive system [clearfil s3 bond (s3), kuraray co., ltd.] to saliva-contaminated enamel, comparing two curing protocols: individual light curing of the adhesive system and the sealant or simultaneous curing of both materials. mesial and distal enamel surfaces from 45 sound third molars were randomly assigned to 6 groups (n=15), according to the bonding technique: i - f was applied to 37% phosphoric acid etched enamel. the other groups were contaminated with fresh human saliva (0.01 ml; 10 s) after acid etching: ii - sb and f were light cured separately; iii - sb and f were light cured together; iv - s3 and f were light cured separately; v - s3 and f were light cured simultaneously; vi - f was applied to saliva-contaminated, acid-etched enamel without an intermediate bonding agent layer. sbs was tested to failure in a universal testing machine at 0.5 mm/min. data were analyzed by one-way anova and fisher's test (α=0.05).the debonded specimens were examined with a stereomicroscope to assess the failure modes. three representative specimens from each group were observed under scanning electron microscopy for a qualitative analysis. mean sbs in mpa were: i-12.28 (±4.29); ii-8.57 (±3.19); iii-7.97 (±2.16); iv-12.56 (±3.11); v-11.45 (±3.77); and vi-7.47 (±1.99). in conclusion, individual or simultaneous curing of the intermediate bonding agent layer and the resin sealant did not seem to affect bond strength to saliva-contaminated enamel. s3/f presented significantly higher sbs than the that of the groups treated with sb etch-and-rinse adhesive system and similar sbs to that of the control group, in which the sealant was applied under ideal dry, noncontaminated conditions.
The impact of occlusal morphology on fissure sealant penetration  [PDF]
Petrovi? Bojan,Markovi? Dejan,Blagojevi? Du?ka
Stomatolo?ki Glasnik Srbije , 2006, DOI: 10.2298/sgs0602087p
Abstract: Introduction: In contemporary preventive dentistry there are numerous experimental in vitro and clinical studies on the growing number of materials for sealing pits and fissures. Aim: the aim of this study was to evaluate the impact of occlusal tooth morphology on penetrating abilities of two types of fissure sealants and measure the unfilled space at the bottom of occlusal groove using scanning electron microscopy (SEM). Materials and methods: The sample consisted of 10 freshly extraced intact premolars and 10 molars randomly divided into 4 groups. In group I (5 premolars), and group II (5 molars) glass ionomer Fuji VII was used as fissure sealant, while in groups III (5 premolars) and IV (5 molars) resin-based sealant (Helioseal-F) was used. Six sections of each tooth were prepared for SEM. Sealant penetration was observed at 30x magnification and the unfilled space at the bottom of the groove at 500x. Sealant penetration in relation to the absolute depth of occlusal grooves was recorded and the unfilled space beneath the sealant was expressed through its greatest diameter. Results were statistically analyzed using χ2 test. Results: There was no statistically significant difference in penetration ability and the unfilled space between tested materials or teeth groups. The average depth of penetration for glass ionomer was 83% and for resin-based sealant 81% of fissure depth. Mean diameters of the unfilled space beneath the sealants were 95 μm (glass ionomer) and 93 μm (resin-based sealant). Shallower penetration of both sealing materials was observed in deep pits and fissures with greater diameter of unfilled space (p<0.05). Conclusion: Based on results of the present study it can be concluded that penetration of contemporary fissure sealants largely depends on occlusal tooth anatomy.
The effect of bonding agents on the microleakage of sealant following contamination with saliva  [cached]
Askarizadeh Nahid,Norouzi Negar,Nemati Saeed
Journal of the Indian Society of Pedodontics and Preventive Dentistry , 2008,
Abstract: Aims : An issue of concern in dentistry is the inadequacy of adhesion and proper sealing following restoration of a tooth, which can lead to marginal leakage. The aim of this study was to evaluate the effect of a bonding agent on the microleakage of a sealant material following contamination with saliva. Materials and Methods : In this experimental research, 48 sound premolars were divided into two groups. The first group received sealant without bonding and the other group was given sealant with bonding. After prophylaxis, the occlusal surfaces were etched with 37% phosphoric acid gel and the teeth were then placed in fresh human saliva for l0 s. Following this, in the first group fissure sealant (Kerr) was applied directly and cured; for the second group sealant was placed and cured after bonding (Single Bond; 3M). All samples were thermocycled (500 cycles; between 5°C and 55°C; dwell time of 30 s). Silver nitrate was used as the leakage tracer. The teeth were sectioned. Microleakage evaluation was made by stereomicroscope at 40x magnification and the results were evaluated with the Mann-Whitney U test. Results : In the group that received sealant without bonding extensive microleakage was seen; placement of sealant with bonding significantly reduced microleakage. Conclusion : In the presence of contamination with saliva, use of bonding under the fissure sealant can reduce microleakage
Effect of Artificial Saliva on the Apatite Structure of Eroded Enamel  [PDF]
Xiaojie Wang,Boriana Mihailova,Arndt Klocke,Stefanie Heidrich,Ulrich Bismayer
International Journal of Spectroscopy , 2011, DOI: 10.1155/2011/236496
Abstract: Citric acid-induced changes in the structure of the mineral component of enamel stored in artificial saliva were studied by attenuated total reflectance infrared spectroscopy as well as complementary electron probe microanalysis and scanning electron microscopy. The results indicate that the application of artificial saliva for several hours (the minimum time period proved is 4?h) leads to slight, partial recovering of the local structure of eroded enamel apatite. However, artificial saliva surrounding cannot stop the process of loosening and breaking of P–O–Ca atomic linkages in enamel subjected to multiple citric acid treatments. Irreversible changes in the atomic bonding within 700?nm thick enamel surface layer are observed after three times exposure for 1?min to aqueous solution of citric acid having a pH value of 2.23, with a 24-hour interval between the individual treatments. The additional treatment with basic fluoride-containing solutions (1.0% NaF) did not demonstrate a protective effect on the enamel apatite structure per se. 1. Introduction Acidic foods or beverages tend to cause tooth erosion, a chemical dissolution of surface hard tissues resulting from a tooth exposure to a variety of acids [1, 2]. Salivary flow plays an important role in minimizing enamel erosion by acid attack [2, 3]. To elucidate how saliva counteracts erosive demineralization, several characteristics of enamel, for example, hardness, surface morphology, mineral loss, and lesion depth, have been investigated [4–7]. It is speculated that saliva buffering capacity, content of calcium and phosphate groups, pellicle acquired on tooth surface and so forth, can act either solely or in combination to inhibit the tooth erosive procedures [8–10]. In vitro and in vivo studies proved that natural saliva and its synthetic substitutes reduce enamel mineral loss [4, 5], enhance enamel rehardening [7, 11], and decrease erosive lesion depth [4, 5]. Sodium fluoride solutions have been aimed at minimizing erosive processes. Recently, it has been reported that the in vitro application of NaF solutions on enamel reduces the acidic-induced mineral loss [12, 13]. Hughes et al. [14] also found that fluoride application in acidic solutions or as a pretreatment reduced enamel erosion although the benefit observed was small and probably not clinically relevant. Hove et al. [15, 16] came to a similar conclusion when investigating enamel exposed to HCl (simulating a gastric reflux situation); while the in vitro study demonstrated a reduction of etching depth by 25% due to a protective effect of
Effect of Enamel Bonding Agents on Pit and Fissure Sealant Retention in An Isolated Situation  [PDF]
Z. Jaberi Ansari,SM. Hashemi
Journal of Dentistry of Tehran University of Medical Sciences , 2008,
Abstract: Objective: The aim of this study was to evaluate the efficacy of enamel bonding agents on pit and fissure sealant retention in a well-isolated situation.Materials and Methods: Thirty-two patients (6-9 years old, all males) with four fully erupted permanent first molars were selected. Their occlusal, buccal, and lingual fissures were sealed according to a split-mouth design using concise light curing white sealant (3M) for the control group and Heliobond (Vivadent) plus sealant for the study group. The retention of sealants was carefully inspected after one year and the data were analyzed by chi-square test.Results: The percentages of complete retention in the study and control groups were 73.2, and 71.4, respectively. Chi-square test revealed no significant difference between these groups (P>0.05)Conclusion: In a dry and isolated situation, application of enamel bonding agent has no significant effect on fissure sealant retention.
Effect of saliva contamination and re-etching time on the shear bond strength of a pit and fissure sealant
Correr, Gisele Maria;Caldo-Teixeira, Angela S.;Alonso, Roberta Caroline Bruschi;Puppin-Rontani, Regina Maria;Sinhoreti, Mário Alexandre Coelho;Correr-Sobrinho, Louren?o;
Journal of Applied Oral Science , 2004, DOI: 10.1590/S1678-77572004000300007
Abstract: the aim of this study was to evaluate the effect of saliva contamination (sct) and re-etching time (ret) on the shear bond strength (sbs) of the fluroshield sealant. forty-five extracted third molars were sectioned and flattened until reach an enamel surface area. then, all samples were etched for 30 sec with 35% phosphoric acid and then they were distributed into 9 groups (n=10) according to sct and ret (seconds), respectively: g1- control (no sct and no ret); g2- 30s and 0s; g3- 60s and 0s; g4-30s and 2s; g5- 30s and 5s; g6- 30s and 15s; g7-60s and 2s; g8- 60s and 5s; g9- 60s and 15s. the sealant was applied according to the manufacturer's instructions. the samples were stored in distilled water at 37oc for 72h and subjected to the sbs test. the results indicated that there was no statistically significant difference between the groups (p>0.05). however, it could be noticed that: 1- the longer the sct, the lower the sbs values; 2 - the longer the ret, the higher the sbs values. it could be concluded that there was a tendency to the shortest sct (30s) associated to the longest ret (5 and 15s) to reach similar sbs values for the control group.
Effect of Saliva Contamination on Microleakage of a Fissure Selant with or without Bonding Agent
AA Soleimani,Z Bahrololumi,M Kabudan,M Mousavi Nasab
Journal of Shahid Sadoughi University of Medical Sciences , 2012,
Abstract: Introduction: Contamination of etched enamel to saliva before placement of sealant prevents the appropriate bonding and results in microleakage. Using bondings is effective for decreasing the microleakage. This experimental study aimed to evaluate the effect of bonding agent on microleakage of a fissure sealant before or after contamination to saliva. Methods: In this experimental study 40 sound premolar teeth were randomly divided into four groups. The prophylaxis was done and the teeth were etched with 37% phosphoric acid gel, then they were washed and dried. In the first group, Seal-Rite fissure sealant and Dentastic (Pulpdent, USA) without saliva contamination, and in the second group sealant with bonding agent after saliva contamination for 10s, were applied and cured for 40s. In the third group, fissure sealant without bonding agent or saliva contamination, and in the fourth group fissure sealant without bonding application was applied after contamination with saliva and then was cured. After thermocycling, the teeth were placed in 50% silver nitrate for 2 hours. The buccolingual sections were applied and microleakage evaluation was made by stereomicroscope at 4X magnifications and results were evaluated with mann-whiteny test. Results: The fissure sealant group without bonding agent showed the most microleakage after contamination to saliva and use of sealant with bonding agent significantly showed decrease of microleakage. Conclusion: Use of bonding agent under fissure sealant in saliva-contamination status is beneficial for decreasing microleakage.
Effect of Unfilled Resin Sealant Surface Coating on the Marginal Leakage of Two Cervical Restorations Viz Light Curing Nanoglass Ionomer and Nanoceramic Composite-An In vitro Stereomicroscopic Dye Penetration Study
S.M. Sharath Chandra,B.K. Raghavendra Rao,Nandan Rao K
Al Ameen Journal of Medical Sciences , 2011,
Abstract: The purpose of this study is to compare the marginal leakage of two aesthetic cervical restorative materials viz the newly introduced light cured nano glass ionomer cement and nano ceramic composites, and also to evaluate the effect of unfilled resin sealant coating on marginal leakage of these aesthetic restorations. Thirty freshly extracted human upper premolars were used for the study. Class V cavities were prepared on the buccal and lingual surface of each tooth, with occlusal margin in enamel and cervical margin in cementum. The teeth were randomly divided into two groups of fifteen teeth each. Cavities of group 1 were restored with nano composite and group 2 were restored with light curing nano glass ionomer cement, following manufacturer’s instructions. After rinsing and drying one thin coat of unfilled resin sealant was applied only on to the surface of lingual restoration and were light polymerized for 15 seconds. The procedures for dye penetration using Methylene Blue were followed and examined under stereomicroscope for evaluation. The data collected were analyzed statistically using Mann-Whitney U test. Nanocomposite recorded less microleakage than nanoglass ionomer cement at occlusal and cervical margins. Results showed that cervical margin had significantly more microleakage than occlusal margin. Palatal surfaces, which were coated with resin sealant showed significantly less dye penetration in comparison with buccal surfaces in both groups. Though the coating of unfilled resin sealant did not completely eliminated microleakage, unfilled resin sealant was definitely effective in reducing microleakage of the esthetic restorations, especially on the gingival margin of the class V restorations.
Retention and penetration of a conventional resin-based sealant and a photochromatic flowable composite resin placed on occlusal pits and fissures  [cached]
Aguilar F,Drubi-Filho B,Casemiro L,Watanabe M.G.C
Journal of the Indian Society of Pedodontics and Preventive Dentistry , 2007,
Abstract: This study compares the retention and penetration of a conventional resin-based sealant (Fluroshield) and a photochromatic flowable composite resin (Tetric Flow Chroma) placed on occlusal pits and fissures and submitted to thermal or chemical cycling regimens. Penetration assessment - ten premolars were sealed with each material, isolated (except for the sealed surface) and immersed in 0.2% Rhodamine B. The teeth were serially sectioned in a mesiodistal direction. The images of the sections were digitized and analyzed (ImageLab). The distance between the most superficial and the deepest points on the occlusal central groove was calculated to determine the groove′s total depth. The length of the central groove filled with the sealant was divided by its total depth to obtain the percentage of sealing of the occlusal groove. Retention assessment - 30 premolars were sealed, their occlusal surfaces were photographed and the area occupied by the sealing materials was demarcated (ImageLab). The teeth were submitted to different treatments: thermocycled, stored in artificial saliva and immersed in acetic acid and saliva (10 cycles/day protocol for 30 days). New photographs were taken to assess the final area occupied by the materials. The difference between the final and initial area was calculated to obtain the material loss. The data was analyzed (two-way anova and Tukey′s test P < 0.05). Both materials presented similar penetration of the occlusal central groove. After thermal and chemical cycling, the materials did not differ with respect to retention, except for immersion in acetic acid. In this case, Tetric Flow Chroma presented greater retention than Fluoroshield.
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