- Email: [email protected]
Microleakage of Class V resin composite restorations placed with self-etching adhesives
Microleakage of Class V resin composite restorations placed with selfetching adhesives William W. Brackett, DDS, MSD,a Larry D. Haisch, DDS,b Megan G. Pearce, BA,c and Martha G. Brackett, DDS, MSDd Medical College of Georgia, Augusta, Ga, and University of Nebraska Medical Center, Lincoln, Neb Statement of problem. Although they are widely available, there is insufficient information about the capability of self-etching adhesives in sealing the margins of resin composite restorations. Purpose. The purpose of this study was to compare the in vitro microleakage of Class V resin composite restorations placed using a strong pH self-etching adhesive, an intermediate pH self-etching adhesive, and an adhesive with a separate etchant and primer. Material and methods. Class V resin composite restorations (n ⫽ 8) were placed in prepared cavities in extracted human third molars using 2 self-etching dentin adhesives, Prompt L-Pop (Strong pH) or One-Up Bond F (Intermediate pH), and an adhesive with a separate etchant and primer, ScotchBond Multi-Purpose. The restored teeth received 1000 thermal cycles between 5°C and 55°C water baths with a 1-minute dwell time and were subsequently subjected to a methylene blue dye challenge and sectioned. The sectioned specimens were scored as demonstrating none, slight, or severe leakage (n⫽16). Ranked data were analyzed using a 1-way analysis of variance at a 5% confidence level. Results. The only leakage observed was along gingival margins, with an incidence of 31% for Prompt L-Pop and One-Up Bond F, and 50% for ScotchBond Multi-Purpose. Conclusion. No significant differences in marginal leakage were found among the adhesives tested. (J Prosthet Dent 2004;91:42-5.)
CLINICAL IMPLICATIONS None of the adhesives evaluated in this in vitro study completely eliminated microleakage along dentin margins. The self-etching adhesives tested appear to be equal in marginal adaptation in Class V restorations to a product with a separate etchant, primer, and adhesive.
D
entin-adhesive resins were originally formulated with separate etchants, primers, and adhesives, but they have evolved such that in some products the adhesive and primer are combined, in others the etchant and primer are combined, whereas in some, all 3 are combined.1 The latter 2 categories are considered “self-etching,” but products in the last categories have been termed “self-etching adhesives.” Van Meerbeek et al1 have classified self-etching products as “strong, intermediate, or mild,” according to their pH, with a strong Presented in part at the annual meeting of the American Association for Dental Research, San Antonio, Texas, March, 2003. This study was supported by UNMC College of Dentistry Student Summer Research Fellowship FY03-05. a Associate Professor, Department of Oral Rehabilitation, Medical College of Georgia. b Associate Professor, Department of Adult Restorative Dentistry, University of Nebraska Medical Center. c Fourth-year Dental Student, College of Dentistry, University of Nebraska Medical Center. d Instructor, Department of Oral Rehabilitation, School of Dentistry, Medical College of Georgia. 42 THE JOURNAL OF PROSTHETIC DENTISTRY
material as having a pH of 1 or less and mild being approximately 2. Whether self-etching products are equivalent to earlier systems with separate etchants, also termed “totaletch” or “etch-and-rinse” systems, has not been established. Clinical data are limited but indicate the performance of self-etching primers and adhesives to be equivalent to earlier formulations in unprepared Class V composite restorations over 2 years.2 Laboratory data indicate the bond strength to dentin of most self-etching products to be equivalent to earlier products,3-5 whereas bond strength to enamel varies according to the study and the products evaluated, with most investigators reporting that self-etching products produce equal or lower enamel bond strengths than total-etch systems.6-9 The tendency to bond less strongly to enamel also appears in studies of laboratory microleakage, with most studies demonstrating self-etching products to be approximately equal along dentin margins to those with separate etchants but less effective along enamel margins.10-12 No clinical study to date has evaluated the VOLUME 91 NUMBER 1
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THE JOURNAL OF PROSTHETIC DENTISTRY
Table I. Technique used for each adhesive tested, pH Adhesive
ScotchBond Multi-Purpose Plus (SMP)
One-UP Bond F (OUB) Prompt L-Pop (PLP)
Technique
pH
Etch 15 seconds, 35% H3PO4, rinse Apply primer, air dry Apply adhesive, light polymerize Mix parts A and B Apply 20 seconds, light polymerize Mix using unit-dosed blister pack Apply with agitation, 15 seconds Air thin, light polymerize
1.0 (etchant)
enamel adhesion of self-etching products under challenging circumstances such as Class IV resin composite restorations. The reduced effectiveness in adhesion to enamel of some self-etching products has been attributed to the relative acidity of the resins with strong self-etchants producing a more effective enamel etch than mild products.1 The purpose of this study was to compare the in vitro microleakage of Class V resin composite restorations placed using 3 products not previously compared, a strong pH self-etching adhesive, an intermediate pH self-etching adhesive, and an adhesive with a separate etchant and primer.
MATERIAL AND METHODS Twelve freshly extracted human third molars were debrided and stored in a 1% thymol solution at room temperature. Within approximately 2 weeks of extraction, Class V preparations were cut into the facial and palatal surface of each with straight carbide fissure burs (no. 256; Brasseler USA, Savannah, Ga) at high speed, using air/water coolant. Preparations were centered on the cemento-enamel junction and were approximately 2 mm deep, 3 mm in height, and 5 mm in width. Maintaining 90-degree cavosurface angles at all preparation margins produced a slightly divergent preparation with no deliberate mechanical retention. Enamel margins received a 45-degree bevel, which encompassed approximately half of the enamel thickness. The estimated Cfactor, or ratio of bonded-to-unbonded surface area of a restoration, produced by this preparation design was 2.5.13 Prompt L-Pop (3M ESPE, St. Paul, Minn), a “strong” self-etching adhesive, and One-Up Bond F (Tokuyama Corp, Tokyo, Japan), an “intermediate” self-etching adhesive, were assigned at random for use in an equal number of restorations of the Class V preparations, along with an adhesive with a separate etchant and primer, ScotchBond Multi-Purpose (3M ESPE). All 3 were applied according to manufacturer’s instructions (Table I). Then restorations of each manufacturer’s respective hybrid composite, (Z 250; 3M ESPE or Palfique Estelite; Tokuyama Corp) were placed in a total of 3 equal increments. Polymerization was accomJANUARY 2004
1.2 0.8
plished with a 20-second exposure of each increment to a fast halogen light source (Elipar TriLight; 3M ESPE), the output of which was verified throughout the study, using the unit’s built-in radiometer, to be 800 mW/ cm2. The tip of the light source was placed as near to the composite as possible without touching the material. Immediately after polymerization, each restoration was contoured with finishing burs (ET9; Brasseler USA) operated at high speed using air/water coolant. All preparation, restoration, and finishing was performed by one author (MGP), simulating clinical instrumentation as nearly as possible. During the week subsequent to placement of the restorations, the teeth were stored in 37°C water. They were removed from storage once and subjected to 1000 thermal cycles between 5°C and 55°C water baths. It is estimated that this number of cycles would represent 2 years’ clinical service (Swartz, ML, personal communication, oral, 1982). Dwell time was 1 minute, with a 5-second transit time between baths. After thermocycling, the apices of the teeth were sealed with sticky wax (Kerr USA, Romulus, Mich) and all tooth surfaces except a 1-mm-wide zone around the margins of each restoration sealed with nail polish (Nail Enamel; Revlon Consumer Products Corp, New York, NY). To minimize dehydration of the restorations, the teeth were replaced in water as soon as the nail polish dried. The teeth were then immersed for 4 hours in a 10% solution of methylene blue dye, rinsed, dried, and invested in clear, autopolymerizing resin (Epoxide; Buehler, Ltd, Lake Bluff, Ill). Each of the 24 restorations was sectioned longitudinally through the center of the restoration with a slowspeed water-cooled diamond saw (Isomet; Buehler, Ltd). The width of the kerf removed by the saw blade was estimated to be 1 mm. This produced a total of 48 sites for evaluation, a sample size of 16 for each adhesive. Specimens were visually evaluated for dye penetration along both occlusal and gingival cavity walls, using a binocular microscope (Olympus America, Inc, Melville, NY) at original magnification ⫻20. Leakage reaching the axial wall was scored severe; leakage not reaching the axial wall was scored slight, 43
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BRACKETT ET AL
Table II. Frequency of microleakage scores, gingival walls, for three dentin adhesives (n⫽16) SMP*
No leakage Slight leakage Severe leakage
8 7 1
OUB*
11 5 0
PLP*
11 4 1
SMP, ScotchBond Multi-Purpose; OUB, One-Up Bond; PLP, Prompt L-Pop. *No significant difference between materials, leakage score rankings, 1-way ANOVA (P⬎.05).
whereas a score of none was assigned to sites exhibiting no leakage. Leakage scores for the entire study were ranked, with ties in the rankings assigned the average rank. Ranked leakage data for the 3 adhesives were compared using a 1-way analysis of variance (␣⫽.05).
RESULTS No leakage was observed along the resin composite/ enamel interface of any specimen, while leakage along gingival cavity walls was observed in 50% of the sections for the total etch adhesive and in 31% of the sections for the 2 self-etching adhesives. Statistical analysis of the data showed no significant difference among the 3 adhesives (P⫽.46). Different leakage scores were assigned on opposite sides of the saw kerf for 12 of the 24 restorations, but for none of the specimens were the scores of none and severe assigned to the same restoration. Complete results are presented in Tables II and III.
DISCUSSION Both of the self-etching products, Prompt L-Pop and One-Up Bond F, evaluated in this study have etchant, primer, and adhesive combined into a single component, allowing the resin restorative material to be placed more quickly than with other types of bonding agents. All self-etching products have the advantage of producing little discomfort when applied to unanesthetized but sensitive dentin, because rinsing and air drying are unnecessary.1 Limitations of both self-etching adhesives tested include the following: no capability for dual polymerization, which can be desirable for indirect adhesive restorations, and for Prompt L-Pop, difficulty in preventing the acid resin from splashing onto adjacent teeth or soft tissue during air-drying. Although most of the self-etching products evaluated in the literature appear to produce adhesion to dentin that is no worse than that of their total etch predecessors,3-5, 11,12 concerns remain about the ability of such products to adequately seal enamel margins, and to bond to enamel with sufficient strength to retain large composite restorations. The findings of this study suggest that self-etching adhesives with strong and intermediate-strength can adequately seal enamel margins for Class V situation, apparently having a pH that is acidic 44
Table III. One-Way ANOVA, dependent variable: leakage score rank Source
DF
Sum of Squares
Mean Squares
Treatment Error
2 45
228 6396
114 142
Total
47
6624
F
P
0.8
.46
enough to adequately etch enamel, which is consistent with the findings of Pashley and Tay7 and of Ibarra et al.6 Both of the self-etching adhesives evaluated in this study appear to be less effective along dentin margins than along enamel margins, which is also in accord with previous studies,10,11 although the combination of etchant with hydrophilic resins is promising, in that it ensures complete resin infiltration into the decalcified layer of dentin.1 The authors acknowledge that laboratory microleakage studies should be considered precursors to clinical studies. The design used in this study, in which the restorations have a relatively high C-factor and are subjected to thermal stresses, is likely to challenge the marginal integrity of restorations, but likely no more than clinical service. If the results are representative, considerable improvement of all classes of dentin-adhesive resin systems is still needed, but on the basis of this and prior studies,3-5,11,12 further clinical trials of Class V resin composite restorations placed with self-etching adhesives are indicated. Future clinical studies are needed to address whether adhesion to enamel is sufficient to retain large restorations which receive occlusal loading, such as Class IV resin composite restorations. Also, it should be determined whether the acidic resins are neutralized during or shortly after restoration, whether there are any pulpal effects resulting from use of selfetching products, and what pH produces the optimum balance between dentin and enamel adhesion.
CONCLUSION Within the limits of this study, no significant difference was observed in the in vitro microleakage of 2 self-etching dentin adhesives and of an adhesive with a separate etchant and primer in Class V resin composite restorations. REFERENCES 1. Van Meerbeek B, De Munck J, Yoshida Y, Inoue S, Vargas M, Vijay P, et al. Buonocore memorial lecture. Adhesion to enamel and dentin: current status and future challenges. Oper Dent 2003;28:215-35. 2. Gordan VV, Mjor IA, Vazquez O, Watson RE, Wilson N. Self-etching primer and resin-based restorative material: two-year clinical evaluation. J Esthet Restor Dent 2002;14:296-302. 3. Hannig M, Reinhardt KJ, Bott B. Composite-to-dentin bond strength, micromorphology of the bonded dentin interface of Class II composite resin restorations using self-etching primers. Oper Dent 2001;26:157-65.
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4. Bouillaguet S, Gysi P, Wataha JC, Ciucchi B, Cattani M, Godin C, et al. Bond strength of composite to dentin using conventional, one-step, and self-etching adhesive systems. J Dent 2001;29:55-61. 5. Inoue S, Vargas MA, Abe Y, Yoshida Y, Lambrechts P, Vanherle G, et al. Microtensile bond strength of eleven contemporary adhesives to dentin. J Adhes Dent 2001;3:237-45. 6. Ibarra G, Vargas MA, Armstrong SR, Cobb DS. Microtensile bond strength of self-etching adhesives to ground and unground enamel. J Adhes Dent 2002;4:115-24. 7. Pashley DH, Tay FR. Aggressiveness of contemporary self-etching adhesives. Part II: etching effects on unground enamel. Dent Mater 2001;17: 430-44. 8. Kanemura N, Sano H, Tagami J. Tensile bond strength to and SEM evaluation of ground and intact enamel surfaces. J Dent 1999;27:523-30. 9. Perdigao J, Geraldeli S. Bonding characteristics of self-etching adhesives to intact versus prepared enamel. J Esthet Restor Dent 2003;15:32-42. 10. Fabianelli A, Kugel G, Ferrari M. Efficacy of self-etching primer on sealing margins of Class II restorations. Am J Dent 2003;16:37-41. 11. Cardoso PE, Placido E, Francci CE, Perdigao J. Microleakage of Class V resin-based composite restorations using five simplified adhesive systems. Am J Dent 1999;12:291-4.
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THE JOURNAL OF PROSTHETIC DENTISTRY
12. Pradelle-Plasse N, Nechad S, Tavernier B, Colon P. Effect of dentin adhesives on the enamel-dentin/composite interfacial microleakage. Am J Dent 2001;14:344-8. 13. Feilzer AJ, De Gee AJ, Davidson CL. Setting stress in composite resin in relation to configuration of the restoration. J Dent Res 1987;66:1636-9. Reprint requests to: DR WILLIAM BRACKETT DEPARTMENT OF ORAL REHABILITATION SCHOOL OF DENTISTRY MEDICAL COLLEGE OF GEORGIA AUGUSTA, GEORGIA 30912-1260 FAX: (706) 721-8349 E-MAIL: [email protected] 0022-3913/$30.00 Copyright © 2004 by The Editorial Council of The Journal of Prosthetic Dentistry.
doi:10.1016/j.prosdent.2003.10.003
45
CLINICAL IMPLICATIONS None of the adhesives evaluated in this in vitro study completely eliminated microleakage along dentin margins. The self-etching adhesives tested appear to be equal in marginal adaptation in Class V restorations to a product with a separate etchant, primer, and adhesive.
D
entin-adhesive resins were originally formulated with separate etchants, primers, and adhesives, but they have evolved such that in some products the adhesive and primer are combined, in others the etchant and primer are combined, whereas in some, all 3 are combined.1 The latter 2 categories are considered “self-etching,” but products in the last categories have been termed “self-etching adhesives.” Van Meerbeek et al1 have classified self-etching products as “strong, intermediate, or mild,” according to their pH, with a strong Presented in part at the annual meeting of the American Association for Dental Research, San Antonio, Texas, March, 2003. This study was supported by UNMC College of Dentistry Student Summer Research Fellowship FY03-05. a Associate Professor, Department of Oral Rehabilitation, Medical College of Georgia. b Associate Professor, Department of Adult Restorative Dentistry, University of Nebraska Medical Center. c Fourth-year Dental Student, College of Dentistry, University of Nebraska Medical Center. d Instructor, Department of Oral Rehabilitation, School of Dentistry, Medical College of Georgia. 42 THE JOURNAL OF PROSTHETIC DENTISTRY
material as having a pH of 1 or less and mild being approximately 2. Whether self-etching products are equivalent to earlier systems with separate etchants, also termed “totaletch” or “etch-and-rinse” systems, has not been established. Clinical data are limited but indicate the performance of self-etching primers and adhesives to be equivalent to earlier formulations in unprepared Class V composite restorations over 2 years.2 Laboratory data indicate the bond strength to dentin of most self-etching products to be equivalent to earlier products,3-5 whereas bond strength to enamel varies according to the study and the products evaluated, with most investigators reporting that self-etching products produce equal or lower enamel bond strengths than total-etch systems.6-9 The tendency to bond less strongly to enamel also appears in studies of laboratory microleakage, with most studies demonstrating self-etching products to be approximately equal along dentin margins to those with separate etchants but less effective along enamel margins.10-12 No clinical study to date has evaluated the VOLUME 91 NUMBER 1
BRACKETT ET AL
THE JOURNAL OF PROSTHETIC DENTISTRY
Table I. Technique used for each adhesive tested, pH Adhesive
ScotchBond Multi-Purpose Plus (SMP)
One-UP Bond F (OUB) Prompt L-Pop (PLP)
Technique
pH
Etch 15 seconds, 35% H3PO4, rinse Apply primer, air dry Apply adhesive, light polymerize Mix parts A and B Apply 20 seconds, light polymerize Mix using unit-dosed blister pack Apply with agitation, 15 seconds Air thin, light polymerize
1.0 (etchant)
enamel adhesion of self-etching products under challenging circumstances such as Class IV resin composite restorations. The reduced effectiveness in adhesion to enamel of some self-etching products has been attributed to the relative acidity of the resins with strong self-etchants producing a more effective enamel etch than mild products.1 The purpose of this study was to compare the in vitro microleakage of Class V resin composite restorations placed using 3 products not previously compared, a strong pH self-etching adhesive, an intermediate pH self-etching adhesive, and an adhesive with a separate etchant and primer.
MATERIAL AND METHODS Twelve freshly extracted human third molars were debrided and stored in a 1% thymol solution at room temperature. Within approximately 2 weeks of extraction, Class V preparations were cut into the facial and palatal surface of each with straight carbide fissure burs (no. 256; Brasseler USA, Savannah, Ga) at high speed, using air/water coolant. Preparations were centered on the cemento-enamel junction and were approximately 2 mm deep, 3 mm in height, and 5 mm in width. Maintaining 90-degree cavosurface angles at all preparation margins produced a slightly divergent preparation with no deliberate mechanical retention. Enamel margins received a 45-degree bevel, which encompassed approximately half of the enamel thickness. The estimated Cfactor, or ratio of bonded-to-unbonded surface area of a restoration, produced by this preparation design was 2.5.13 Prompt L-Pop (3M ESPE, St. Paul, Minn), a “strong” self-etching adhesive, and One-Up Bond F (Tokuyama Corp, Tokyo, Japan), an “intermediate” self-etching adhesive, were assigned at random for use in an equal number of restorations of the Class V preparations, along with an adhesive with a separate etchant and primer, ScotchBond Multi-Purpose (3M ESPE). All 3 were applied according to manufacturer’s instructions (Table I). Then restorations of each manufacturer’s respective hybrid composite, (Z 250; 3M ESPE or Palfique Estelite; Tokuyama Corp) were placed in a total of 3 equal increments. Polymerization was accomJANUARY 2004
1.2 0.8
plished with a 20-second exposure of each increment to a fast halogen light source (Elipar TriLight; 3M ESPE), the output of which was verified throughout the study, using the unit’s built-in radiometer, to be 800 mW/ cm2. The tip of the light source was placed as near to the composite as possible without touching the material. Immediately after polymerization, each restoration was contoured with finishing burs (ET9; Brasseler USA) operated at high speed using air/water coolant. All preparation, restoration, and finishing was performed by one author (MGP), simulating clinical instrumentation as nearly as possible. During the week subsequent to placement of the restorations, the teeth were stored in 37°C water. They were removed from storage once and subjected to 1000 thermal cycles between 5°C and 55°C water baths. It is estimated that this number of cycles would represent 2 years’ clinical service (Swartz, ML, personal communication, oral, 1982). Dwell time was 1 minute, with a 5-second transit time between baths. After thermocycling, the apices of the teeth were sealed with sticky wax (Kerr USA, Romulus, Mich) and all tooth surfaces except a 1-mm-wide zone around the margins of each restoration sealed with nail polish (Nail Enamel; Revlon Consumer Products Corp, New York, NY). To minimize dehydration of the restorations, the teeth were replaced in water as soon as the nail polish dried. The teeth were then immersed for 4 hours in a 10% solution of methylene blue dye, rinsed, dried, and invested in clear, autopolymerizing resin (Epoxide; Buehler, Ltd, Lake Bluff, Ill). Each of the 24 restorations was sectioned longitudinally through the center of the restoration with a slowspeed water-cooled diamond saw (Isomet; Buehler, Ltd). The width of the kerf removed by the saw blade was estimated to be 1 mm. This produced a total of 48 sites for evaluation, a sample size of 16 for each adhesive. Specimens were visually evaluated for dye penetration along both occlusal and gingival cavity walls, using a binocular microscope (Olympus America, Inc, Melville, NY) at original magnification ⫻20. Leakage reaching the axial wall was scored severe; leakage not reaching the axial wall was scored slight, 43
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BRACKETT ET AL
Table II. Frequency of microleakage scores, gingival walls, for three dentin adhesives (n⫽16) SMP*
No leakage Slight leakage Severe leakage
8 7 1
OUB*
11 5 0
PLP*
11 4 1
SMP, ScotchBond Multi-Purpose; OUB, One-Up Bond; PLP, Prompt L-Pop. *No significant difference between materials, leakage score rankings, 1-way ANOVA (P⬎.05).
whereas a score of none was assigned to sites exhibiting no leakage. Leakage scores for the entire study were ranked, with ties in the rankings assigned the average rank. Ranked leakage data for the 3 adhesives were compared using a 1-way analysis of variance (␣⫽.05).
RESULTS No leakage was observed along the resin composite/ enamel interface of any specimen, while leakage along gingival cavity walls was observed in 50% of the sections for the total etch adhesive and in 31% of the sections for the 2 self-etching adhesives. Statistical analysis of the data showed no significant difference among the 3 adhesives (P⫽.46). Different leakage scores were assigned on opposite sides of the saw kerf for 12 of the 24 restorations, but for none of the specimens were the scores of none and severe assigned to the same restoration. Complete results are presented in Tables II and III.
DISCUSSION Both of the self-etching products, Prompt L-Pop and One-Up Bond F, evaluated in this study have etchant, primer, and adhesive combined into a single component, allowing the resin restorative material to be placed more quickly than with other types of bonding agents. All self-etching products have the advantage of producing little discomfort when applied to unanesthetized but sensitive dentin, because rinsing and air drying are unnecessary.1 Limitations of both self-etching adhesives tested include the following: no capability for dual polymerization, which can be desirable for indirect adhesive restorations, and for Prompt L-Pop, difficulty in preventing the acid resin from splashing onto adjacent teeth or soft tissue during air-drying. Although most of the self-etching products evaluated in the literature appear to produce adhesion to dentin that is no worse than that of their total etch predecessors,3-5, 11,12 concerns remain about the ability of such products to adequately seal enamel margins, and to bond to enamel with sufficient strength to retain large composite restorations. The findings of this study suggest that self-etching adhesives with strong and intermediate-strength can adequately seal enamel margins for Class V situation, apparently having a pH that is acidic 44
Table III. One-Way ANOVA, dependent variable: leakage score rank Source
DF
Sum of Squares
Mean Squares
Treatment Error
2 45
228 6396
114 142
Total
47
6624
F
P
0.8
.46
enough to adequately etch enamel, which is consistent with the findings of Pashley and Tay7 and of Ibarra et al.6 Both of the self-etching adhesives evaluated in this study appear to be less effective along dentin margins than along enamel margins, which is also in accord with previous studies,10,11 although the combination of etchant with hydrophilic resins is promising, in that it ensures complete resin infiltration into the decalcified layer of dentin.1 The authors acknowledge that laboratory microleakage studies should be considered precursors to clinical studies. The design used in this study, in which the restorations have a relatively high C-factor and are subjected to thermal stresses, is likely to challenge the marginal integrity of restorations, but likely no more than clinical service. If the results are representative, considerable improvement of all classes of dentin-adhesive resin systems is still needed, but on the basis of this and prior studies,3-5,11,12 further clinical trials of Class V resin composite restorations placed with self-etching adhesives are indicated. Future clinical studies are needed to address whether adhesion to enamel is sufficient to retain large restorations which receive occlusal loading, such as Class IV resin composite restorations. Also, it should be determined whether the acidic resins are neutralized during or shortly after restoration, whether there are any pulpal effects resulting from use of selfetching products, and what pH produces the optimum balance between dentin and enamel adhesion.
CONCLUSION Within the limits of this study, no significant difference was observed in the in vitro microleakage of 2 self-etching dentin adhesives and of an adhesive with a separate etchant and primer in Class V resin composite restorations. REFERENCES 1. Van Meerbeek B, De Munck J, Yoshida Y, Inoue S, Vargas M, Vijay P, et al. Buonocore memorial lecture. Adhesion to enamel and dentin: current status and future challenges. Oper Dent 2003;28:215-35. 2. Gordan VV, Mjor IA, Vazquez O, Watson RE, Wilson N. Self-etching primer and resin-based restorative material: two-year clinical evaluation. J Esthet Restor Dent 2002;14:296-302. 3. Hannig M, Reinhardt KJ, Bott B. Composite-to-dentin bond strength, micromorphology of the bonded dentin interface of Class II composite resin restorations using self-etching primers. Oper Dent 2001;26:157-65.
VOLUME 91 NUMBER 1
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4. Bouillaguet S, Gysi P, Wataha JC, Ciucchi B, Cattani M, Godin C, et al. Bond strength of composite to dentin using conventional, one-step, and self-etching adhesive systems. J Dent 2001;29:55-61. 5. Inoue S, Vargas MA, Abe Y, Yoshida Y, Lambrechts P, Vanherle G, et al. Microtensile bond strength of eleven contemporary adhesives to dentin. J Adhes Dent 2001;3:237-45. 6. Ibarra G, Vargas MA, Armstrong SR, Cobb DS. Microtensile bond strength of self-etching adhesives to ground and unground enamel. J Adhes Dent 2002;4:115-24. 7. Pashley DH, Tay FR. Aggressiveness of contemporary self-etching adhesives. Part II: etching effects on unground enamel. Dent Mater 2001;17: 430-44. 8. Kanemura N, Sano H, Tagami J. Tensile bond strength to and SEM evaluation of ground and intact enamel surfaces. J Dent 1999;27:523-30. 9. Perdigao J, Geraldeli S. Bonding characteristics of self-etching adhesives to intact versus prepared enamel. J Esthet Restor Dent 2003;15:32-42. 10. Fabianelli A, Kugel G, Ferrari M. Efficacy of self-etching primer on sealing margins of Class II restorations. Am J Dent 2003;16:37-41. 11. Cardoso PE, Placido E, Francci CE, Perdigao J. Microleakage of Class V resin-based composite restorations using five simplified adhesive systems. Am J Dent 1999;12:291-4.
JANUARY 2004
THE JOURNAL OF PROSTHETIC DENTISTRY
12. Pradelle-Plasse N, Nechad S, Tavernier B, Colon P. Effect of dentin adhesives on the enamel-dentin/composite interfacial microleakage. Am J Dent 2001;14:344-8. 13. Feilzer AJ, De Gee AJ, Davidson CL. Setting stress in composite resin in relation to configuration of the restoration. J Dent Res 1987;66:1636-9. Reprint requests to: DR WILLIAM BRACKETT DEPARTMENT OF ORAL REHABILITATION SCHOOL OF DENTISTRY MEDICAL COLLEGE OF GEORGIA AUGUSTA, GEORGIA 30912-1260 FAX: (706) 721-8349 E-MAIL: [email protected] 0022-3913/$30.00 Copyright © 2004 by The Editorial Council of The Journal of Prosthetic Dentistry.
doi:10.1016/j.prosdent.2003.10.003
45