|Year : 2008 | Volume
| Issue : 2 | Page : 64-66
The effect of bonding agents on the microleakage of sealant following contamination with saliva
Nahid Askarizadeh, Negar Norouzi, Saeed Nemati
Department of Pediatric Dentistry, Dental School, Islamic Azad University, Tehran, Iran
Department of Pediatric Dentistry, Dental School, Islamic Azad University, No: 4, 10th Neyestan, Pasdaran Ave., Tehran
| 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
Keywords: Bonding agent, fissure sealant, microleakage, saliva contamination
|How to cite this article:|
Askarizadeh N, Norouzi N, Nemati S. The effect of bonding agents on the microleakage of sealant following contamination with saliva. J Indian Soc Pedod Prev Dent 2008;26:64-6
|How to cite this URL:|
Askarizadeh N, Norouzi N, Nemati S. The effect of bonding agents on the microleakage of sealant following contamination with saliva. J Indian Soc Pedod Prev Dent [serial online] 2008 [cited 2014 Mar 12];26:64-6. Available from: http://www.jisppd.com/text.asp?2008/26/2/64/41618
| Introduction|| |
In children aged 5-17, 56-70% of all dental lesions are occlusal caries.  Preventive capability of pit and fissure sealants are related to their ability to block the pit and fissures on the tooth surface. This will prevent penetration of fermentable carbohydrates which can be used by the bacteria remaining on the fissures and also prevent colonization by new bacteria. Bis-GMA is the base of most of the fissure sealants available in the market.  The long-term clinical success of fissure sealants is closely related to their proper handling.  A dry enamel surface is necessary to achieve good adhesion. It is not easy to apply rubber dam in children without anesthesia and, also, cotton-roll isolation requires four-handed dentistry; moreover, in these conditions, contamination during swallowing and tongue movement is still possible.  Microleakage is defined as the passage of bacteria, fluids, molecules, and ions between the teeth and the sealing material.  It is considered to be the main reason for caries, pulpitis, and necrosis.  Frield et al . reported that 49.4% of all restorations had to be replaced because of their marginal defect.  To promote the sealing capacity, new adhesive systems have been introduced  and it is claimed that the use of these materials is the best way to prevent microleakage.  Dentin bonding systems consist of bifunctional molecules: 1) A methacrylate group that bonds to the restorative resin by chemical interaction and 2) a functional group that is able to penetrate wet dentin surface.  The use of dentin bonding agents between the tooth and fissure sealant can be beneficial for reducing microleakage when there is contamination of the enamel. , Different results have been shown by studies, with some indicating no changes in retention and microleakage in spite of the use of bonding agents. , It is also reported that all adhesives may not be able to achieve sealing of margin restorations and thus prevent microleakage.  Because of these different findings, we examined the effect of a bonding agent on sealant microleakage in the presence of contamination with saliva; we wished to assess the usefulness of this technique for fissure sealant therapy and its potential for decreasing the caries rate in contaminated conditions.
| Materials and Methods|| |
Forty eight premolars with no caries, crack, or restoration, which were extracted for orthodontic purposes, were selected for this in vitro experimental study. After removing debris and applying prophylaxis with non-fluoridated paste, the teeth were disinfected with thymol 0.2% and then randomly assigned to two groups, with 24 teeth in each group. In group 1, sealant was placed without bonding and in group 2 bonding was placed before applying sealant. Teeth were etched (37% phosphoric acid gel) for 20 s, rinsed for 40 s, and then dried for 15 s with oil-free compressed air.  The principal examiner collected her own saliva and placed it on the etched enamel surface with the use of a syringe until a film covered the entire enamel surface. This was left undisturbed for 10 s and was then blotted with a small sponge, leaving a moist enamel surface. , After the above procedures, in group 1, fissure sealant (Kerr) was applied and cured for 40 s. In group 2, bonding (Single Bond; 3M) was used according to the manufacturer's instructions and cured for 20 s under fissure sealant. All specimens were thermocycled for 500 cycles between 5°C and 55°C, with a 30 s dwell time. Following thermocycling, the root apexes of the teeth were sealed with photo-cured glass inomer and the teeth were coated with two layers of nail polish, except for the restorations and a 1 mm rim of tooth structure around the restorations.  The samples were immersed in silver nitrate solution (50% by weight, pH ~6-7) and kept in complete darkness for 2 h. They were then thoroughly rinsed in tap water and immersed for 6 h in photographic developing solution under fluorescent light to facilitate reduction of silver ions to metallic sliver; the teeth were then again rinsed. , Next, the teeth were embedded in self-curing acrylic resin to prevent chipping of the material and the resin blocks were sectioned with a cutting machine, buccolingually and parallel to the long axis, into two fragments. After the above procedures, the length of dye penetration at the sealant/tooth interface was examined under a stereomicroscope with 40 x magnification. The criteria for the amount of dye microleakege was the level of maximum dye penetration.
Grading of microleakage was based on the following criteria: 
Grade 0 = No penetration
Grade 1 = Dye penetration more than zero to and up to one-thirds of the sealant/tooth interface
Grade 2 = Dye penetration extending from one-third to two-third of the length of the sealant/tooth interface
Grade 3 = Dye penetration more than two-thirds of the length of the sealant/tooth interface
The data were analyzed using the Mann-Whitney U test.
| Results|| |
In this experimental study, microleakage was observed to be less in group 2 [Table 1]. The difference between the two groups was statistically significant ( P < 0.001). Dye penetration and length of sealant/tooth interface in the two groups are shown in [Table 2] and [Table 3].
| Discussion|| |
In the presence of contamination with saliva, use of the bonding agent under the sealant reduced microleakage. In the control group (group 1), 100% of the teeth showed grade 3 microleakage, whereas in group 2, grade 1 microleakage was the most common (63%).
Lussi and Duangthip also showed that use of a bonding agent in situations where there is saliva contamination is beneficial for microleakage reduction and it can also increase sealant retention.  In that study, 5% methylene blue was used, whereas in our study the tracer used was silver nitrate, which provided more precise measurement of the microleakage. 
In another study, Feigal and Hebling assessed the effect of bonding as an intermediate layer on microleakage reduction on saliva contaminated enamel and they also showed that using bonding agent as an intermediate layer reduces microleakage on saliva-contaminated enamel.  In their research, microleakage was reported as the average of all fragments, whereas in our study the maximum amount was selected. With regard to microleakage assessment, our study was more precise as we studied both the length of dye penetration and also its grade, whereas Feigal and Hebling did not assess the in their study grades were not mentioned.
The result of present study is in agreement with Bodur et al .  In their study, teeth were thermocycled under 1000 cycles but in the present study 500 cycles were selected.
Feigal, Hitt and Splieth  believe that using bonding agent is useful to increase fissure sealant retention on teeth contaminated with saliva. Choi  and his colleagues reported similar findings form laboratory studies on bovine enamel that was contaminated with moisture.  These reports are also in agreement with the results of our study.
The results of the clinical study by Boksman et al . indicated that the use of bonding does not increase retention,  which is contrary to our findings. Boksman's research was performed in isolated environment but the present study was done under saliva-contaminated conditions.
In another research, Pinar et al . assessed the clinical performance of sealants with and without a bonding agent and showed that the placement of bonding under the fissure sealant did not affect the clinical success of the sealant.  The difference between the results of this study compared to us was due to a difference in the design set up of these two studies.
In a critical review article, De Munck et al . stated that all current adhesives appear to be incapable of sealing the restoration margins and thus preventing microleakage.  They had emphasized the need for further researches, in different settings, to elucidate the exact nature and behavior of bonding in the prevention of microleakage.
| Conclusion|| |
The findings of this study showed that the use of bonding agent under fissure sealants on saliva-contaminated teeth is beneficial for microleakage reduction. In situations in which control of saliva and isolation is impossible, the use of bonding for increasing the quality of fissure sealant therapy is useful.
| References|| |
|1.||Pardi A, Sindhoreti MA, Pereira AC, Ambrosano GM, Meneghim C. In vitro evaluation of microleakage of different materials used as pit and fissure sealants. Braz Dent J 2006;17:49-52 |
|2.||Moore K, Avery DR. Dental materials. In : McDonald, Avery, Dean. editors. Dentistry for the child and adolescent. 8 th ed. Mosby: 2004. p. 359. |
|3.||Barroso JM, Lessa FC, Palma Dibb RG, Torres CP, Pecora J, Borsatto MC. Shear bond strength of pit and fissure sealants to saliva contaminated and non contaminated enamel. J Dent Child 2005;72:95-9. |
|4.||Bodur H, Tulunoglu O, Uctasli M, Alacam A. The effect of bonding agents on the microleakage and bond strength of sealant in primary teeth. J Oral Rehabil 1999;26:436-41. |
|5.||Hidalgo AC, Lajarin L p, Lillo OC, Ballesta CG. Marginal microleakage of two fissure sealants: A Comparative study. J Dent Child 2003;70:24-8. |
|6.||Abidi A. Assessing the effect of laser palsi ND-YAG on Microleakage of Cl V composite restorations [dissertation]. Tehran: Shahid Beheshti University Dental School; 1999. p. 42. |
|7.||Kimiaie S. Assessing the effect of type of composite restorations on microleakage of CL II restorations [dissertation]. Tehran: Shahid Beheshti University Dental School; 2003. p. 56. |
|8.||Amaral CM, TakeoHara A, Pimenta LA, Rodrigues AL. Microleakage of hydrophilic adhesive systems in class V composite restorations. Am J Dent 2001;14:31-3. |
|9.||Perdigao J, Swift EJ. Fundementals, Concepts of enamel and dentin adhesion. In : Roberson TM, Hymann H, Swift EJ, editors. Sturdevant's art and science of operative dentistry. 4 th ed. Mosby: 2002. p. 238. |
|10.||Lussi A, Duangthip D. Microleakage and penetration ability of resin sealant versus bonding system when applied following contamination. Pediatr Dent 2003;25:505-11. |
|11.||Feigal R, Hebling J. Use of one-Bottle adhesive as an intermediate bonding layer to reduce sealant microleakage on Saliva-Contaminated enamel. Am J Dent 2000;13:187-91. |
|12.||Boksman L, McConnell RJ, Carson B, McCutcheon-Jones EF. 2-year clinical evalvation of two pit and fissure sealants placed with and without the use of a bonding agent. Quintessence Int 1993;24:131-3. [PUBMED] |
|13.||Pinar A, Sepet E, Aren G, Bolukbasi N, Ulukapi H, Turan N. Clinical performance of sealants with and without a bonding agent. Quintessence Int 2005;36:355-60. |
|14.||De Munck J, Vanlanduyt K, Peumans M, Poitevin A, Lambrechts P, Bream M, et al . A critical review of the durability of adhesion to tooth tissue: Method and results. J Dent Res 2005;84:118-32. |
|15.||Moeenian M. Comparing the microleakage between filtek composite and Helioseal F as a fissure sealant on premolars [dissertation]. Tehran: Islamic Azad University Dental School; 2006. p. 35. |
|16.||Cardoso P, Placido E, Francci C, Perdigao J. Microleakage of class V resin-based composite restorations using five simplified adhesive systems. Am J Dent 1999;12:291-4. |
|17.||Wieczkowski G Jr, Yu XY, Davis EL, Joynt RB. Microleakage in various dentin bonding agent-Composite resin systems. Oper Dent 1992;5:62-7. [PUBMED] |
|18.||Alani AH, Toh CG. Detection of microleakage around dental restorations: A review. Oper Dent 1997;22:173-85 [PUBMED] |
[Table 1], [Table 2], [Table 3]
|This article has been cited by|
|| Effect of blood contamination on microleakage of orthodontic bracket bonding materials
| ||Shi, Y.-T., Pin, Y., Shan, L.-H., Song, J.-S. |
| || Journal of Clinical Rehabilitative Tissue Engineering Research. 2009; 13(29): 5649-5652 |