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Dentin Bonding Systems: A Review of Current Products and Techniques
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D EN I BONDING SYSTEMS:
A REVIEW OF CURRENT PRODUCTS AND TECHNIQUES G LE N H. J O H N S O N , D.D .S., M .S ., L. V IR G IN IA P O W E L L , D .M .D ., G LE N N E. G O R D O N , D .D .S ., M .S.
Q here is m uch interest and activity in dentistry today with dentin bonding systems. Unlike bonding to enamel, which has enjoyed clinical success since first introduced by Buonocore in 1955,' effective adhesion to dentin has been m ore elusive since dentin is biologically active and is complex in composition and morphologic structure. Hum an dentin has the following general com position expressed in volum e percent: 45 percent inorganic content, 33 percent organic com pounds and the rem aining 22 percent is chiefly w ater.2To be successful, the dentin bonding systems m ust adhere and rem ain sealed in the presence of dentinal fluids, vital tissues and a porous, nonuniform substrate. In addition, a surface layer of debris called the sm ear layer m ust be removed or altered to achieve effective adhesion to dentin. Finally, the bond and seal of the d entin bonding system m ust be durable and capable of w ithstand ing the complex and changing chemical, therm al and mechanical stresses of the oral environment. Many products are available to dentists, w ith m ost systems undergoing continual change in efforts to improve clinical perform ance. A m anufacturer wishing to obtain the ADA seal of acceptance for a dentin (and enam el) bonding system m ust subm it evidence of biological safety and clinical effectiveness. For a product to be accorded 34
JADA, Vol. 122, July 1991
ABSTRACT
Many dentists are facing decisions regarding selection and use o f dentin bonding systems. This article presents information on existing products and provides guidance on their use based on laboratory and clinical evidence. full acceptance, the rate of failure of restorations cannot exceed 10 percent in either of two independent, three-year clinical trials.3Unfortunately, many products are released for use before clinical evaluations have been completed.4This report supplies the dental team with inform ation about current dentin bonding systems, discusses clinical perform ance and makes recom m endations about their use. PRODUCTS
At the time this report was prepared, there were 11 dentin bonding systems available to dentists in the United States, with several appearing recently. A description of each system is supplied in Table 1. Product inform ation was verified by each m anufacturer. Since terminology varies appreciably, nam es for each com ponent within a given system are those used by the m anu facturer. Chemical abbreviations are often used for complex organic
compounds. With nine of the 11 bonding systems, the sm ear layer and superficial dentin are first treated w ith one or more chemical agents (for example, etchant, cleanser, conditioner, prim er) to prepare the substrate to accept the composite bonding resin. The sm ear layer is completely removed and dentinal tubules are partially opened as a first step in the following systems: All-Bond (all etch), Clearfil Photo-Bond, Gluma, Mirage Bond, Restobond-3 and Tenure Solution. The agents used for this purpose are either nitric acid, phosphoric acid or ethylene diam ine tetra-acetic acid (EDTA). Other systems omit acid treatm ent of dentin as a separate procedure bu t contain an acid in another step (All-Bond [no etch], Scotchbond 2, Pertac, Syntac), which in effect removes or alters the sm ear layer.45 The next step in promoting adhesion to dentin is application of a bifunctional molecule(s)— m ost often referred to as a prim er. One functional group typically contains a hydrophilic com ponent to facilitate wetting and adhesion to dentin. The opposing end of the molecule contains a group th at will readily bond to the composite resin. In an analogous situation, the inorganic filler in composite resin is treated with a bifunctional compound called a “silanecoupler,” one end of which bonds to the filler and the other to the resin matrix. As noted, the prim er
and surface cleansing agent are occasionally combined. With some systems, the prim er also contains com pounds intended to prom ote a chemical bond to inorganic or organic com ponents of the dentin. It has been suggested th at the Gluma system achieves a covalent bond of HEMA to a collagen-glutaraldehyde complex.6 The nature of this bond has been further investigated and is dis cussed later. For the same reason, the Prisma Universal Bond-3 system has been form ulated to include 1% glutaraldehyde. Three systems (Clearfil Photo-Bond, Prism a Universal Bond-3 and X-R Bond) also contain phosphonated acrylic esters in the prim er which, according to the m anufacturers, prom ote ionic bonding to calcium ions in the dentin. The final step for all systems is the placem ent of a bonding resin which precedes the application of the composite resin. This step is variously referred to as sealer, resin, bonding resin or adhesive. An im portant and consistent com ponent in the bonding resin is a derivative of methylmethacrylate, which will bond covalently with a functional group on the prim er as well as to the composite resin. Many bonding resins also contain some of the constituents of the prim er (HEMA, PENTA, phosphonated resins) to further prom ote adhesion to dentin. The shelf-life of products stored at room tem perature ranges from 12 to 30 months (Table 1). Al though dentin bonding systems are often packaged with composite resins, m anufacturers were asked to supply the suggested retail price of th eir dentin bonding system as a separate purchase. The cost for a d entin bonding kit ranges from $45 to $150. P art of the difference in cost betw een products may depend on variation in the total
am ount of m aterial supplied in the adhesive kit. No attem pt was made to calculate the cost per milliliter since there are several compon ents in each kit and individual com ponents may be used at different rates. The m inim um total time required for placem ent of a typical Class V composite of each system is shown in Table 2. In addition, each step of the dentin bonding procedure up to placem ent of the composite resin is indicated w ithin the bar. The tim e for each step is shown in parentheses. Times of application range from a low of 30 seconds for Pertac to a high of 2.5 m inutes for Restobond-3. Pertac requires the fewest steps with three individual steps to as many as eight steps with Tenure Solution. Instructions for application of the dentin bonding system are supplied by each m anufacturer, but with varying details. Keep a copy of the m anufacturer’s instructions at each operatory or with each kit, and m aintain strict adherence to the instructions for optimal results. Refer to the telephone num bers given in Table 1 to obtain additional information. INDICATIONS
For cavity preparations completely surrounded by enamel, use either conventional enamel bonding resin or a dentin bonding system to attain an effective seal.7Time and cost considerations favor the enamel bonding resin for conserv ative preparations completely surrounded by enamel. For larger cavity preparations surrounded by enamel, use a dentin bonding system for bonding to both enam el and dentin, thereby increasing the potential for m aintaining a seal. Class II, III and IV preparations, which contain little or no enamel at the gingival margins, present an
increased risk for leakage and recurrent caries. The m ost conservative approach is to use a light-cured glass ionom er liner to cover the dentin.8However, results from clinical trials of posterior composite resins suggest th at dentin bonding systems are as effective as glass ionom er liners in m aintaining a seal, as evidenced by little postoperative sensitivity910 and by a relatively low incidence of recurrent caries.811 Currently, 10 posterior composite resin products have been accorded ADA proviGLOSSARY
BIS-GMA bisphenol glycidyl methacrylate BPDM biphenyl dim ethacrylate E D T A
ethylene diamine tetra-acetic acid HEMA hydroxyethyl methacrylate MDP m ethacrylozyloxydecyldihydrogenphosphate NPG N-phenylglycine NTG-GMA N -tolyglycine-glycidyl methacrylate PEG-DMA polyethylene glycol dimethacrylate PENTA phosphonated pentaacrylate ester PM DM pyrom ellitic acid diethyl methacrylate SAMA succinic acid and HEMA TEG-DMA triethylene glycol di methacrylate UDMA urethane dim ethacrylate
JADA, Vol. 122, July 1991 35
TABLE 1. DEMTIN BONDING SYSTEM DESCRIPTIONS SYSTEM/ MANUFACTURER
COMPONENTS
PRECAUTIONS
COST: (dentin bonding system only)
All-B ond/B isco Dental Products 1(800)247-3368
Clearfil Photo-B ond/ J. M orita USA, Inc. 1(800)752-9729
Gluma/Miles, Inc., Dental Products (219)291 -0661
Etchant— 10% phosphoric acid (AllEtch Technique) C onditioner— 20% SAMA in water Primers— (A) 2% NTG-GMA in ethanol and acetone (B) 16% BPDM in acetone Bonding Resin— BISGMA, UDMA, HEMA
Etchant-----40% phosphoric acid, colloidal silica Catalyst— BIS-GMA, 10-MDP, HEMA, camphoroquinone, benzoyl peroxide Universal— aromatic sodium sulfinate, tertiary aromatic amine in ethanol
Cleanser— 16% EDTA Primer— 35% HEMA, 5% glutaraldehyde in water Sealer— BIS-GMA resin
1. May require as many as five coats of primer 2. Shelf life= 24 months
1. 1:1 mix o f catalyst and universal must be fresh
3. Shelf life (not released by manufacturer)
1. Shelf life=30 months at least
$1 24
2. Sealing resin may require separate light curing
Conditioner— 4% NPG in 2.5% nitric acid in aqueous solution Adhesive— 10% PM DM in acetone
1. Conditioner cartridge requires careful handling to prevent air contam ¡nation 2. Adhesive must be allowed to evaporate 3. Refrigeration recommended 4. Shelf life=1 2 months
Pertac Universal Bond/ESPE-Premier Sales Corp. 1 (800)344-8235
(No conditioner or primer required) Adhesive— methacrylated carboxylic acid, hydrophilic and hydrophobic dimethacrylates, camphoroquinone, activator
1. Refrigeration recommended
JADA, Vol. 122, July 1991
$1 oo
2. Refrigeration required
M irage-B ond/ Mirage Dental Systems 1(800)359-7111
36
$1 49
2. Shelf life=12 months
$119
$45
SYSTEM/ MANUFACTURER
COMPONENTS
PRECAUTIONS
COST: (dentin bonding system only)
Prisma Universal Bond-3/C aulk/ Dentsply (302)422-4511
Primer— 30% HEMA + 6% PENTA in ethanol Adhesive— 5% PENTA, 55% urethane resin, 39% polymerizable monomers (TEGDMA, HEMA, etc.), <1 % glutaraldehyde, <1 % photoinitiators
1. Shelf life=1 2 months
Restobond-3 Lee Pharmaceuticals (81 8)442-31 41
C onditioner— 4% NPG in 2.5% nitric acid in aqueous solution Sealant— 10% PMDM in acetone Resin— (unfilled resinnot identified)
1. Sealant must be allowed to evaporate
S cotchbond 2/3M (61 2)733-2968
Primer— 2.5% maleic acid, 58.5% HEMA in water Adhesive— 62.5% BISGMA 37.5% HEMA, Photoinitiators
1. Adhesive m ust not be air-thinned to less than 75 nm 2. Refrigeration recommended 3. Shelf life (not released by manufacturer)
Syntac/I vociar North America, Inc. 1 (800)533-6825
Primer— 25% TEG-DMA + 4% maleic acid in acetone and water Adhesive—35% PEGDMA, 5% glutaraldehyde in w ater Resin— (Heliobond) 60% BIS-GMA, 40% TEG-DMA
1. Newly introduced to the U.S.
Tenure S olution/ Den-mat, Inc. 1(800)433-6628
X-R Bond/Kerr Manufacturing Co. 1(800)521 -2854
$91
$75
2. Refrigeration recommended 3. Shelf life=1 2 months
$1 30
$85
2. Cool storage recommended but not necessary 3. Shelf life=24 months
Conditioner—3.5% aluminum oxalate in 2.5% nitric acid in aqueous solution Bonding agent— (2 solutions) Soln A— 5% NTGGMA in acetone Soln B— 10% PMDM in acetone
1. Solutions A & B must be freshly mixed (1:1); allow to evaporate after applying
Primer— 3.75% phosphonated dim ethacrylate ester, 50% ethanol, 46% water, camphoroquinone Resin— 10% phosphonated dim ethacrylate ester, UDMA, aliphatic dim eth acrylate, camphoroquinone
1. Shelf life=24 months
$117
2. Shelf life=1 8 months
$55-$66
JADA, Vol. 122, July 1991 37
TA8LE1. TIME ÄND STEPS REQUIRED FDR USE BE EACH SYSTEM All-Bond (no etch) Conditioner (30); dry (5); primer (30); dry (5); bond resin (1 0); light cure (20)
. * UO s e c -
All-Bond (all etch) Etchant (15); rinse (15); dry (5); primer (30); dry (5); bond resin (1 0); light cure (20)
^ Sec‘
Clearfil Photo-Bond Etchant (15); rinse (30); dry (10); mix (10); apply (5); dry (5); light cure (1 5)
sec'
Gluma Cleanser (30); rinse (1 5); dry (5); primer (30); dry (10); sealer (10); air thin (5)
. — — 1U £> sec.
Mirage Bond Conditioner (30); dry (30); adhesive (10); evaporate (40); bond resin (10); air thin (5)
125
sec.
Pertac Universal Bond Apply (5); air thin (5); light cure (20)
Prisma Universal Bond 3 Primer (30); dry (10); adhesive (10); air thin (10); light cure (15)
75
se c.
Restobond-3 Conditioner (30); dry (30); sealer (10); evaporate (40); dry (10); bond resin (10); light cure (20)
150
Scotchbond 2 Primer (30); dry i-light ■j. cure (25) /nr,
(15); adhesive (10); dry (10);
J7u s e c .
Syntac Primer (1 5); air thin (5); adhesive (10); air thin (15); bond resin (15); light cure (20)
Tenure Solution Conditioner (1 5); rinse (30); dry (10); bond agent (1 0); evaporate (20); bond resin (10); air thin (5); light cure (20)
120
se c.
X-R Bond Primer (30); dry (10); light cure (10); bond resin (10); light cure (20)
O
30 sec.
60 sec.
N um bers in p aren th eses refer to seconds required for step.
38
JADA, Vol. 122, July 1991
qq
sec
90 sec.
120 sec.
150 sec.
s e c.
Figure 1. This scanning electron microscope photograph demonstrates a dentin surface which has been demineralized and subsequently treated with a primer. The sample has been fractured, allowing a three-dimensional view of the dentin surface and tubules. The intertubular dentin has been affected to a depth of approximately 1 micrometer or 0.001 millimeter. The marker = 5um. (A) Adhesive layer; (B) Demineralized layer infiltrated by resin; (C) Portion of resin tag. (Courtesy of Dr. Robert L. Erickson)
sional or full acceptance,12based on successful clinical trials in which at least two-thirds of the restorations m ust be Class II restorations and m any have been placed using dentin bonding systems. Careful placem ent of restorations and excellent patient oral hygiene may well have a more im portant role in the success of the Class II posterior composite restor ation th an the decision of what treatm ent to apply to the dentin. The Class V lesion, with little or no enamel available to supplem ent adhesion and seal of the restor ation, provides the ultim ate challenge to the dentin bonding system. The recom m endation is to use dentin bonding systems “on an
Figure 2. This fractured specimen shows a dentinbonding resin which has flowed evenly over and infiltrated into the primed surface. Resin extensions into the tubules can be seen but the tags are incomplete as portions were broken off during specimen fracture. The interlocking arrangement of the adhesive into primed intratubular and intertubular dentin provides the seal and retention of the dentin bonding system. The marker = 5i. m. (A) Demineralized and primed layer. (Courtesy of Dr. Robert L. Erickson)
experim ental basis” with prepar ation retention features common to a preparation for nonadhesive restorative materials.413 The new ADA acceptance guidelines for dentin and enamel bonding systems require place m ent of Class V restorations w ithout m echanical retentive features other than acid etching of enam el.3Rates of failure cannot exceed 5 percent after one year to be labeled ADA-provisionally acceptable and cannot be greater than 10 percent after three years for a system to be fully acceptable. No products have received the ADA seal under the new guide lines, but three products have received a seal for clinical trials
conducted under the original guidelines. In this case, acid etching of enam el was not perm itted to evaluate only the bond to dentin; however, allowable rates of failure were higher. Of the products listed in Table 1, only Scotchbond-2 has been aw arded the seal ADA-acceptable, w ith three-year failure rates near, but within the limit of 20 percent. Tenure Solution has been given the seal provisionally acceptable based on six-month results in which failure rates did not exceed 10 percent.12Until long term clinical success is dem on strated, dentin bonding systems for Class V applications should be used w ith caution and with an JADA, Vol. 122, July 1991
39
expectation of higher rates of failure in com parison to all glass ionom er or dental amalgam restorations.14'20 BOND MECHANISM
Studies of the nature of the bond to dentin attained by Scotchbond-2 and Gluma dentin bonding systems indicate th at the bond is principally micromechanical. The proposed m echanism, based on SEM analysis, is that hydrophilic m onom ers infiltrate into a surface zone of dem ineralized dentin to form an interlocking network after polymerization.5An independent study used spectroscopy to analyze the nature of the bond for the same two systems plus Tenure. The conclusions were consistent in th at no evidence of covalent bonding to dentin was evident for any of the systems.21 Many investigators have shown via SEM th at the current dentin bonding systems form resin tags into dentin tubules and are intim ately adapted to all dentinal surfaces to which they come into contact. Thus, even though the substrates differ, the principal m echanism for bonding to dentin is the same as for bonding to enamel. TECHNIQUE CONSIDERATIONS
Regarding preparation features, clinical success was not enhanced w hen a cervical retentive groove in dentin was used in conjunction with Class V preparations contain ing occlusal enamel.15It is generally recom m ended to bevel the enam el before etching; however, a clinical study of posterior composite restorations22 and laboratory study of Class V restorations23did not dem onstrate an advantage for beveling. Several studies have shown that low-viscosity (microfill) 40
JADA, Vol. 122, July 1991
composites have greater clinical success with Class V applications than do higher Dr. Gordon is viscosity hybrid assistant professor, composites.24'29It Department of Restorative has been Dentistry, SM-56, suggested that University of microfilled Washington, Seattle. composites are more successful because they can absorb more energy as the tooth bends in function; and may expand with w ater sorption to enhance retention. The recom m endation for use of microfilled composite resins is only for Class V applications, as hybrid composites perform well in other applications. Other factors which relate to a higher likelihood of loss of Class V restorations are stressful occlusion, increasing age of tooth and location on the m andibular arch.29 It is generally recommended to place composite resin into the cavity in increm ents to prevent bulk polymerization shrinkage. A recent thorough review of labora tory studies did not, however, dem onstrate an advantage for increm ental curing.30Finally, it is vitally im portant to attain excellent control of the operating field with the use of rubber dam and retraction to expose the gingival aspects of the lesion. The effectiveness of dentin bonding systems depends on m aintaining an uncontam inated substrate (dentin and enamel) while they are being placed; thus, effective field isolation is required for clinical success. SAFETY ISSUES
Since dentin is altered with the use of current dentin bonding systems, there are concerns about biological safety. The notion of acid
conditioning of dentin with dentinbonding systems is particularly troublesome, since dentists have long been adm onished to avoid etching dentin while etching enamel. Brannstrom 31cautioned against acid treatm ent of dentin, as tubules are opened, thereby increasing the risk of bacterial infection and pulpal sensitivity. In opposition, Fusayama32has long m aintained that an effective seal can be obtained by first etching dentin with phosphoric acid, followed by sealing with resin and composite. As noted earlier, most current dentin bonding systems contain mild acids which, in effect, etch dentin. Recent clinical studies evaluated the use of acid cleansers on dentin in combination with dentin bonding systems and reported no pulpal problems.11'33-37 Gluma, Scotchbond-2, and older versions of Tenure—each contain ing a different acid conditionerhave been available for use in the United States for several years. As an indirect m easure of acceptance, the Complaint Reporting Program directed by the ADA Council on Dental Materials, Instrum ents and Equipm ent has not received many complaints regarding the use of dentin bonding systems. Caution is advised until additional Dr. Poweil is research is com assistant professor, pleted on the Department of Restorative effects of direct Dentistry, SM-56, etching of University of Washington, Seattle. dentin with phosphoric acid,38especially since this option has only recently been made available commercially to U.S. dentists (All-bond [all etch] and Clearfil Photo-Bond).
Histopathological evaluations using prim ates and cytotoxicity tests in vitro generally confirm the biological safety of several of the chemicals used in the dentin bonding systems.3WSM1With a new test for cytotoxicity, researchers recently reported th at there was decreased cellular activity in the presence of HEMA and glutaraldehyde42and decreased DNA and protein synthesis in the presence of unpolym erized BIS-GMA and UDMA.43The reported incidence of pulpal sensitivity is low, but one study has docum ented some sensitivity w ith the use of a dentin bonding system.19 If signs and symptoms of pulpal sensitivity occur after use of a dentin bonding system, first suspect microleakage as the cause. Air and cold sensitivity are common complaints with leakage since these stimuli can cause fluid m ovem ent in dentinal tubules, thereby causing pain. Seal the suspected area and check with air and water. If sensitivity persists, replace the restoration with an alternate filling material. CONCLUSIONS
To enhance the clinical success of restorations using a dentin bonding system: ■» provide excellent field isolation and m aintain clean surfaces; *« carefully follow all of the m anufacturer’s directions; ■» use a protective liner for deep lesions; and «■* provide preparation retention features when there is little or no enamel available to supplem ent adhesion. The best advice for dental practitioners is to be vigilant when using these systems. Monitor the restorations at each recall for symptoms of sensitivity and signs of leakage. Finally, report problems to the ADA Council on
Dr. Johnson is chairman of the ADA Council on Dental Materials, Instruments and Equipment and is associate professor,
Dental Mater ials, Instru m ents and Equipment, as use of dental restorative m aterials among practitioners represents the ultim ate clinical test of products.
Department of Restorative Dentistry, SM-56, University of Washington, Seattle 98195. Address requests for reprints to Dr. Johnson.
Publications of nam es of products does n o t imply endorsem ent by the Am erican D ental Association.
1. B uonocore MG. A sim ple m ethod of in creasing the ad h esio n of acrylic filling m aterials to enam el surfaces. J D ent Res 1955; 34:849-53. 2. Ten Cate, AR. Oral histology: developm ent, stru ctu re a n d form ation. St. Louis: Mosby; 1989:157. 3. ADA Council o f Dental M aterials, In strum ents and Equipm ent. ADA Guidelines for Dentin and E nam el Adhesive M aterials. March, 1991. 4. Bowen RL, Eichm iller FC, M arjenhoff WA, Rupp NW. A dhesive bonding of com posites. J Am Coll D ent 1989; 56:10-3. 5. Erickson RL. M echanism and clinical im plications of bond form ation for tw o d e n tin bonding agents. Am J D ent 1989; 2:117-23. 6. M unksgaard EC, Asm ussen E. Bond s tren g th betw een d e n tin a n d restorative resins m ediated by m ixtures of HEMA a n d glutaraldehyde. J D ent Res 1984; 63:1087-9. 7. S parrius 0 , G rossm an ES. Marginal leakage of com posite resin resto ratio n s in com bination w ith dentinal and en am el bonding agents. J P ro sth et D ent 1989; 61:67884. 8. Leinfelder KF. Using com posite resin as a posterior restorative m aterial. JA D A 1991; 122 (3):65-70. 9. Jo h n so n GH, Gordon GE, Bales DJ. Postoperative sensitivity associated w ith posterior com posite and am algam restorations. O per D ent 1988; 13:66-73. 10. Duke ES, Robbins JW, Howell ML, Sum m itt JB. Clinical evaluation of a d en tin adhesive system in cervical abrasions. J D ent Res 1991; 70:395. 11. Shintani H, Satou N, Satou J. Clinical evaluation of two po sterio r com posite resin s retain ed w ith bonding agents. J P ro sth et D ent 1989; 62:627- 32. 12. Council of D ental M aterials, In strum ents and Equipm ent. Clinical pro d u cts in dentistry. Chicago: A m erican D ental Association, 1990. 13. V anherle G, Lam brechts P, Braem M. An evaluation of d ifferent adhesive restorations in cervical lesions. J Pro sth et D ent 1991; 65:341-7. 14. Bastos P, Teixeira L, L einfelder K. Three-year clinical evaluation o f Scotchbond-2 as a d entinal adhesive. J D ent Res 1991; 70:395. 15. Wiley PM, D ennison JB, G regory WA. Clinical evaluation o f a cervical reten tio n groove in dentin bonding. J D ent Res 1991; 70:395. 16. Duke ES, Robbins JW, Snyder DE. D entin adhesive evaluation fo r restoring cervical abrasions lesions. J D ent Res 1991; 70:457. 17. v an Dijken JW. T he effect of cavity p retreatm en t p ro ced u res on d e n tin bonding: a four-year evaluation. J P ro sth et D ent 1990; 64:148-52. 18. M ount GJ. Restorations of eroded areas. JADA 1990; 120:31-5. 19. Powell LV, Gordon GE, Jo h n so n GH. Sensitivity of restored Class V abrasio n /ero sio n lesions. JADA 1990; 121:694-6. 20. Tyas MJ, B urns GA, Byrne PF, C unningham PJ, Dobson BC, W iddop FT. Clinical evaluation of Scotchbond: three-year results. A ust D ent J 1989; 34:277-9. 21. Edler TL, Krikorian E, Thom pson VP. FTIR surface analysis of d e n tin and d e n tin bonding agents. J D ent Res 1991; 70:458. 22. Isenberg BP, L einfelder KF. Efficiency of beveling
p osterior com posite resin preparations. J E sth et D ent 1990; 2:70-3. 23. Litkowski L, Sw ierczewski M, Durkee M, S trassler H. Root surface m arginal m icroleakage o f th re e d e n tin bonding agents. J D ent Res 1989; 68:207. 24. Chohayeb AA, R upp NW. Com parison of m icroleakage of experim ental and selected com m ercially available bonding system . D ent M ater 1989; 5:241-3. 25. H ansen EK, A sm ussen E. M arginal adap tatio n of p osterior resins: effect o f dentin-bonding a g en t and hygroscopic expansion. D ent M ater 1989; 5:122-6. 26. Crim GA. Influence of bonding agents and com posites o n m icroleakage. J P ro sth et D ent 1989; 61:5714. 27. H eym ann HO, Stu rd ev an t JR, B runson WD, W ilder AD, Bayne SC, Sluder TB. Two-year clinical d en tin adhesive study: cervical lesions. J D ent Res 1989; 68:186. 28. Prati C, Nucci C. M arginal gap, m icroleakage a n d sh e ar bond stren g th of adhesive restorative system s. J D ent Res 1989; 68:996. 29. H eym ann HO, Stu rd ev an t JR, Bayne S, W ilder AD, Sluder TB, B runson WD. Exam ining tooth flexure effects on cervical restorations: a two-year clinical study. JADA 1991; 122(6):41-7. 30. Soderholm , K-JM. Correlation of in vivo a n d in vitro perform ance of adhesive restorative m aterials: a rep o rt of th e ASC MD156 task group on test m ethods for the ad h esio n of restorative m aterials. Dent M ater 1991; 7:74-83. 31. Brannstrom M. Infection b en eath com posite resin restorations: can it be avoided? O per D ent 1987; 12:158-63. 32. Fusayam a T. Factors a n d prevention of pulp irritatio n by adhesive com posite resin restorations. Q uintessence In t 1987; 18:633-41. 33. Q vist V, Stoltze K, Qvist J. H um an pulp reactions to resin resto ratio n s perform ed w ith different acid-etch restorative procedures. Acta Odontol Scand 1989; 47:25363. 34. Bowen RL, Rupp NW, Eichm iller FC, Stanley HR. Clinical biocom patibility of a n experim ental dentineenam el adhesive for com posites. In t D ent J 1989; 39:24752. 35. B losser RL, Rupp NW, Stanley HR, Bowen RL. Pulpal a n d m icro-organism responses to two experim ental dental bonding system s. D ent M ater 1989; 5:140-4. 36. W endt SL, L einfelder KF. Clinical evaluation of a com posite resin /b o n d in g system . J D ent Res 1989; 68:233. 37. G w innett AJ, K anca J. M icromorphological relationship betw een resin and d en tin in vivo a n d in vitro. J D ent Res 1991; 70:457. 38. Duke ES. Adhesion and tooth-colored restoratives. C u rren t O pinion D ent 1991; 1:163-71. 39. W aknine S, Gable P, Schulm an A. Physicom echanical, adhesion a n d cytotoxicity characterization of eleven com m ercial d en tin adhesives. J Dent. Res 1989; 68:375. 40. Thom as CA, Reel DC, Dam m DD, M itchell RJ, Crim GA. T h ree d e n tin bonding agents in hum ans. J D ent Res 1989; 68:868. 41. Pam eijer CH, Stanley HR. H istological reactions in prim ates to a d e n tin bonding agent. J D ent Res 1991; 70:384. 42. Hanks CT, Parsell JR, Straw n SE, W ataha JC. Cytotoxicity of d e n tin bonding ag en ts w ith m onolayer and dentin diffusion. J D ent Res 1991; 70:384. 43. Straw n SE, Nassiri MR, Hanks CT, Cam eron MJ, W ataha JC, Craig RG. Bis-GMA and UDMA effects on cell m etabolism and cell cycle. J D ent Res 1991; 70:384.
JADA, Vol. 122, July 1991 41
D EN I BONDING SYSTEMS:
A REVIEW OF CURRENT PRODUCTS AND TECHNIQUES G LE N H. J O H N S O N , D.D .S., M .S ., L. V IR G IN IA P O W E L L , D .M .D ., G LE N N E. G O R D O N , D .D .S ., M .S.
Q here is m uch interest and activity in dentistry today with dentin bonding systems. Unlike bonding to enamel, which has enjoyed clinical success since first introduced by Buonocore in 1955,' effective adhesion to dentin has been m ore elusive since dentin is biologically active and is complex in composition and morphologic structure. Hum an dentin has the following general com position expressed in volum e percent: 45 percent inorganic content, 33 percent organic com pounds and the rem aining 22 percent is chiefly w ater.2To be successful, the dentin bonding systems m ust adhere and rem ain sealed in the presence of dentinal fluids, vital tissues and a porous, nonuniform substrate. In addition, a surface layer of debris called the sm ear layer m ust be removed or altered to achieve effective adhesion to dentin. Finally, the bond and seal of the d entin bonding system m ust be durable and capable of w ithstand ing the complex and changing chemical, therm al and mechanical stresses of the oral environment. Many products are available to dentists, w ith m ost systems undergoing continual change in efforts to improve clinical perform ance. A m anufacturer wishing to obtain the ADA seal of acceptance for a dentin (and enam el) bonding system m ust subm it evidence of biological safety and clinical effectiveness. For a product to be accorded 34
JADA, Vol. 122, July 1991
ABSTRACT
Many dentists are facing decisions regarding selection and use o f dentin bonding systems. This article presents information on existing products and provides guidance on their use based on laboratory and clinical evidence. full acceptance, the rate of failure of restorations cannot exceed 10 percent in either of two independent, three-year clinical trials.3Unfortunately, many products are released for use before clinical evaluations have been completed.4This report supplies the dental team with inform ation about current dentin bonding systems, discusses clinical perform ance and makes recom m endations about their use. PRODUCTS
At the time this report was prepared, there were 11 dentin bonding systems available to dentists in the United States, with several appearing recently. A description of each system is supplied in Table 1. Product inform ation was verified by each m anufacturer. Since terminology varies appreciably, nam es for each com ponent within a given system are those used by the m anu facturer. Chemical abbreviations are often used for complex organic
compounds. With nine of the 11 bonding systems, the sm ear layer and superficial dentin are first treated w ith one or more chemical agents (for example, etchant, cleanser, conditioner, prim er) to prepare the substrate to accept the composite bonding resin. The sm ear layer is completely removed and dentinal tubules are partially opened as a first step in the following systems: All-Bond (all etch), Clearfil Photo-Bond, Gluma, Mirage Bond, Restobond-3 and Tenure Solution. The agents used for this purpose are either nitric acid, phosphoric acid or ethylene diam ine tetra-acetic acid (EDTA). Other systems omit acid treatm ent of dentin as a separate procedure bu t contain an acid in another step (All-Bond [no etch], Scotchbond 2, Pertac, Syntac), which in effect removes or alters the sm ear layer.45 The next step in promoting adhesion to dentin is application of a bifunctional molecule(s)— m ost often referred to as a prim er. One functional group typically contains a hydrophilic com ponent to facilitate wetting and adhesion to dentin. The opposing end of the molecule contains a group th at will readily bond to the composite resin. In an analogous situation, the inorganic filler in composite resin is treated with a bifunctional compound called a “silanecoupler,” one end of which bonds to the filler and the other to the resin matrix. As noted, the prim er
and surface cleansing agent are occasionally combined. With some systems, the prim er also contains com pounds intended to prom ote a chemical bond to inorganic or organic com ponents of the dentin. It has been suggested th at the Gluma system achieves a covalent bond of HEMA to a collagen-glutaraldehyde complex.6 The nature of this bond has been further investigated and is dis cussed later. For the same reason, the Prisma Universal Bond-3 system has been form ulated to include 1% glutaraldehyde. Three systems (Clearfil Photo-Bond, Prism a Universal Bond-3 and X-R Bond) also contain phosphonated acrylic esters in the prim er which, according to the m anufacturers, prom ote ionic bonding to calcium ions in the dentin. The final step for all systems is the placem ent of a bonding resin which precedes the application of the composite resin. This step is variously referred to as sealer, resin, bonding resin or adhesive. An im portant and consistent com ponent in the bonding resin is a derivative of methylmethacrylate, which will bond covalently with a functional group on the prim er as well as to the composite resin. Many bonding resins also contain some of the constituents of the prim er (HEMA, PENTA, phosphonated resins) to further prom ote adhesion to dentin. The shelf-life of products stored at room tem perature ranges from 12 to 30 months (Table 1). Al though dentin bonding systems are often packaged with composite resins, m anufacturers were asked to supply the suggested retail price of th eir dentin bonding system as a separate purchase. The cost for a d entin bonding kit ranges from $45 to $150. P art of the difference in cost betw een products may depend on variation in the total
am ount of m aterial supplied in the adhesive kit. No attem pt was made to calculate the cost per milliliter since there are several compon ents in each kit and individual com ponents may be used at different rates. The m inim um total time required for placem ent of a typical Class V composite of each system is shown in Table 2. In addition, each step of the dentin bonding procedure up to placem ent of the composite resin is indicated w ithin the bar. The tim e for each step is shown in parentheses. Times of application range from a low of 30 seconds for Pertac to a high of 2.5 m inutes for Restobond-3. Pertac requires the fewest steps with three individual steps to as many as eight steps with Tenure Solution. Instructions for application of the dentin bonding system are supplied by each m anufacturer, but with varying details. Keep a copy of the m anufacturer’s instructions at each operatory or with each kit, and m aintain strict adherence to the instructions for optimal results. Refer to the telephone num bers given in Table 1 to obtain additional information. INDICATIONS
For cavity preparations completely surrounded by enamel, use either conventional enamel bonding resin or a dentin bonding system to attain an effective seal.7Time and cost considerations favor the enamel bonding resin for conserv ative preparations completely surrounded by enamel. For larger cavity preparations surrounded by enamel, use a dentin bonding system for bonding to both enam el and dentin, thereby increasing the potential for m aintaining a seal. Class II, III and IV preparations, which contain little or no enamel at the gingival margins, present an
increased risk for leakage and recurrent caries. The m ost conservative approach is to use a light-cured glass ionom er liner to cover the dentin.8However, results from clinical trials of posterior composite resins suggest th at dentin bonding systems are as effective as glass ionom er liners in m aintaining a seal, as evidenced by little postoperative sensitivity910 and by a relatively low incidence of recurrent caries.811 Currently, 10 posterior composite resin products have been accorded ADA proviGLOSSARY
BIS-GMA bisphenol glycidyl methacrylate BPDM biphenyl dim ethacrylate E D T A
ethylene diamine tetra-acetic acid HEMA hydroxyethyl methacrylate MDP m ethacrylozyloxydecyldihydrogenphosphate NPG N-phenylglycine NTG-GMA N -tolyglycine-glycidyl methacrylate PEG-DMA polyethylene glycol dimethacrylate PENTA phosphonated pentaacrylate ester PM DM pyrom ellitic acid diethyl methacrylate SAMA succinic acid and HEMA TEG-DMA triethylene glycol di methacrylate UDMA urethane dim ethacrylate
JADA, Vol. 122, July 1991 35
TABLE 1. DEMTIN BONDING SYSTEM DESCRIPTIONS SYSTEM/ MANUFACTURER
COMPONENTS
PRECAUTIONS
COST: (dentin bonding system only)
All-B ond/B isco Dental Products 1(800)247-3368
Clearfil Photo-B ond/ J. M orita USA, Inc. 1(800)752-9729
Gluma/Miles, Inc., Dental Products (219)291 -0661
Etchant— 10% phosphoric acid (AllEtch Technique) C onditioner— 20% SAMA in water Primers— (A) 2% NTG-GMA in ethanol and acetone (B) 16% BPDM in acetone Bonding Resin— BISGMA, UDMA, HEMA
Etchant-----40% phosphoric acid, colloidal silica Catalyst— BIS-GMA, 10-MDP, HEMA, camphoroquinone, benzoyl peroxide Universal— aromatic sodium sulfinate, tertiary aromatic amine in ethanol
Cleanser— 16% EDTA Primer— 35% HEMA, 5% glutaraldehyde in water Sealer— BIS-GMA resin
1. May require as many as five coats of primer 2. Shelf life= 24 months
1. 1:1 mix o f catalyst and universal must be fresh
3. Shelf life (not released by manufacturer)
1. Shelf life=30 months at least
$1 24
2. Sealing resin may require separate light curing
Conditioner— 4% NPG in 2.5% nitric acid in aqueous solution Adhesive— 10% PM DM in acetone
1. Conditioner cartridge requires careful handling to prevent air contam ¡nation 2. Adhesive must be allowed to evaporate 3. Refrigeration recommended 4. Shelf life=1 2 months
Pertac Universal Bond/ESPE-Premier Sales Corp. 1 (800)344-8235
(No conditioner or primer required) Adhesive— methacrylated carboxylic acid, hydrophilic and hydrophobic dimethacrylates, camphoroquinone, activator
1. Refrigeration recommended
JADA, Vol. 122, July 1991
$1 oo
2. Refrigeration required
M irage-B ond/ Mirage Dental Systems 1(800)359-7111
36
$1 49
2. Shelf life=12 months
$119
$45
SYSTEM/ MANUFACTURER
COMPONENTS
PRECAUTIONS
COST: (dentin bonding system only)
Prisma Universal Bond-3/C aulk/ Dentsply (302)422-4511
Primer— 30% HEMA + 6% PENTA in ethanol Adhesive— 5% PENTA, 55% urethane resin, 39% polymerizable monomers (TEGDMA, HEMA, etc.), <1 % glutaraldehyde, <1 % photoinitiators
1. Shelf life=1 2 months
Restobond-3 Lee Pharmaceuticals (81 8)442-31 41
C onditioner— 4% NPG in 2.5% nitric acid in aqueous solution Sealant— 10% PMDM in acetone Resin— (unfilled resinnot identified)
1. Sealant must be allowed to evaporate
S cotchbond 2/3M (61 2)733-2968
Primer— 2.5% maleic acid, 58.5% HEMA in water Adhesive— 62.5% BISGMA 37.5% HEMA, Photoinitiators
1. Adhesive m ust not be air-thinned to less than 75 nm 2. Refrigeration recommended 3. Shelf life (not released by manufacturer)
Syntac/I vociar North America, Inc. 1 (800)533-6825
Primer— 25% TEG-DMA + 4% maleic acid in acetone and water Adhesive—35% PEGDMA, 5% glutaraldehyde in w ater Resin— (Heliobond) 60% BIS-GMA, 40% TEG-DMA
1. Newly introduced to the U.S.
Tenure S olution/ Den-mat, Inc. 1(800)433-6628
X-R Bond/Kerr Manufacturing Co. 1(800)521 -2854
$91
$75
2. Refrigeration recommended 3. Shelf life=1 2 months
$1 30
$85
2. Cool storage recommended but not necessary 3. Shelf life=24 months
Conditioner—3.5% aluminum oxalate in 2.5% nitric acid in aqueous solution Bonding agent— (2 solutions) Soln A— 5% NTGGMA in acetone Soln B— 10% PMDM in acetone
1. Solutions A & B must be freshly mixed (1:1); allow to evaporate after applying
Primer— 3.75% phosphonated dim ethacrylate ester, 50% ethanol, 46% water, camphoroquinone Resin— 10% phosphonated dim ethacrylate ester, UDMA, aliphatic dim eth acrylate, camphoroquinone
1. Shelf life=24 months
$117
2. Shelf life=1 8 months
$55-$66
JADA, Vol. 122, July 1991 37
TA8LE1. TIME ÄND STEPS REQUIRED FDR USE BE EACH SYSTEM All-Bond (no etch) Conditioner (30); dry (5); primer (30); dry (5); bond resin (1 0); light cure (20)
. * UO s e c -
All-Bond (all etch) Etchant (15); rinse (15); dry (5); primer (30); dry (5); bond resin (1 0); light cure (20)
^ Sec‘
Clearfil Photo-Bond Etchant (15); rinse (30); dry (10); mix (10); apply (5); dry (5); light cure (1 5)
sec'
Gluma Cleanser (30); rinse (1 5); dry (5); primer (30); dry (10); sealer (10); air thin (5)
. — — 1U £> sec.
Mirage Bond Conditioner (30); dry (30); adhesive (10); evaporate (40); bond resin (10); air thin (5)
125
sec.
Pertac Universal Bond Apply (5); air thin (5); light cure (20)
Prisma Universal Bond 3 Primer (30); dry (10); adhesive (10); air thin (10); light cure (15)
75
se c.
Restobond-3 Conditioner (30); dry (30); sealer (10); evaporate (40); dry (10); bond resin (10); light cure (20)
150
Scotchbond 2 Primer (30); dry i-light ■j. cure (25) /nr,
(15); adhesive (10); dry (10);
J7u s e c .
Syntac Primer (1 5); air thin (5); adhesive (10); air thin (15); bond resin (15); light cure (20)
Tenure Solution Conditioner (1 5); rinse (30); dry (10); bond agent (1 0); evaporate (20); bond resin (10); air thin (5); light cure (20)
120
se c.
X-R Bond Primer (30); dry (10); light cure (10); bond resin (10); light cure (20)
O
30 sec.
60 sec.
N um bers in p aren th eses refer to seconds required for step.
38
JADA, Vol. 122, July 1991
sec
90 sec.
120 sec.
150 sec.
s e c.
Figure 1. This scanning electron microscope photograph demonstrates a dentin surface which has been demineralized and subsequently treated with a primer. The sample has been fractured, allowing a three-dimensional view of the dentin surface and tubules. The intertubular dentin has been affected to a depth of approximately 1 micrometer or 0.001 millimeter. The marker = 5um. (A) Adhesive layer; (B) Demineralized layer infiltrated by resin; (C) Portion of resin tag. (Courtesy of Dr. Robert L. Erickson)
sional or full acceptance,12based on successful clinical trials in which at least two-thirds of the restorations m ust be Class II restorations and m any have been placed using dentin bonding systems. Careful placem ent of restorations and excellent patient oral hygiene may well have a more im portant role in the success of the Class II posterior composite restor ation th an the decision of what treatm ent to apply to the dentin. The Class V lesion, with little or no enamel available to supplem ent adhesion and seal of the restor ation, provides the ultim ate challenge to the dentin bonding system. The recom m endation is to use dentin bonding systems “on an
Figure 2. This fractured specimen shows a dentinbonding resin which has flowed evenly over and infiltrated into the primed surface. Resin extensions into the tubules can be seen but the tags are incomplete as portions were broken off during specimen fracture. The interlocking arrangement of the adhesive into primed intratubular and intertubular dentin provides the seal and retention of the dentin bonding system. The marker = 5i. m. (A) Demineralized and primed layer. (Courtesy of Dr. Robert L. Erickson)
experim ental basis” with prepar ation retention features common to a preparation for nonadhesive restorative materials.413 The new ADA acceptance guidelines for dentin and enamel bonding systems require place m ent of Class V restorations w ithout m echanical retentive features other than acid etching of enam el.3Rates of failure cannot exceed 5 percent after one year to be labeled ADA-provisionally acceptable and cannot be greater than 10 percent after three years for a system to be fully acceptable. No products have received the ADA seal under the new guide lines, but three products have received a seal for clinical trials
conducted under the original guidelines. In this case, acid etching of enam el was not perm itted to evaluate only the bond to dentin; however, allowable rates of failure were higher. Of the products listed in Table 1, only Scotchbond-2 has been aw arded the seal ADA-acceptable, w ith three-year failure rates near, but within the limit of 20 percent. Tenure Solution has been given the seal provisionally acceptable based on six-month results in which failure rates did not exceed 10 percent.12Until long term clinical success is dem on strated, dentin bonding systems for Class V applications should be used w ith caution and with an JADA, Vol. 122, July 1991
39
expectation of higher rates of failure in com parison to all glass ionom er or dental amalgam restorations.14'20 BOND MECHANISM
Studies of the nature of the bond to dentin attained by Scotchbond-2 and Gluma dentin bonding systems indicate th at the bond is principally micromechanical. The proposed m echanism, based on SEM analysis, is that hydrophilic m onom ers infiltrate into a surface zone of dem ineralized dentin to form an interlocking network after polymerization.5An independent study used spectroscopy to analyze the nature of the bond for the same two systems plus Tenure. The conclusions were consistent in th at no evidence of covalent bonding to dentin was evident for any of the systems.21 Many investigators have shown via SEM th at the current dentin bonding systems form resin tags into dentin tubules and are intim ately adapted to all dentinal surfaces to which they come into contact. Thus, even though the substrates differ, the principal m echanism for bonding to dentin is the same as for bonding to enamel. TECHNIQUE CONSIDERATIONS
Regarding preparation features, clinical success was not enhanced w hen a cervical retentive groove in dentin was used in conjunction with Class V preparations contain ing occlusal enamel.15It is generally recom m ended to bevel the enam el before etching; however, a clinical study of posterior composite restorations22 and laboratory study of Class V restorations23did not dem onstrate an advantage for beveling. Several studies have shown that low-viscosity (microfill) 40
JADA, Vol. 122, July 1991
composites have greater clinical success with Class V applications than do higher Dr. Gordon is viscosity hybrid assistant professor, composites.24'29It Department of Restorative has been Dentistry, SM-56, suggested that University of microfilled Washington, Seattle. composites are more successful because they can absorb more energy as the tooth bends in function; and may expand with w ater sorption to enhance retention. The recom m endation for use of microfilled composite resins is only for Class V applications, as hybrid composites perform well in other applications. Other factors which relate to a higher likelihood of loss of Class V restorations are stressful occlusion, increasing age of tooth and location on the m andibular arch.29 It is generally recommended to place composite resin into the cavity in increm ents to prevent bulk polymerization shrinkage. A recent thorough review of labora tory studies did not, however, dem onstrate an advantage for increm ental curing.30Finally, it is vitally im portant to attain excellent control of the operating field with the use of rubber dam and retraction to expose the gingival aspects of the lesion. The effectiveness of dentin bonding systems depends on m aintaining an uncontam inated substrate (dentin and enamel) while they are being placed; thus, effective field isolation is required for clinical success. SAFETY ISSUES
Since dentin is altered with the use of current dentin bonding systems, there are concerns about biological safety. The notion of acid
conditioning of dentin with dentinbonding systems is particularly troublesome, since dentists have long been adm onished to avoid etching dentin while etching enamel. Brannstrom 31cautioned against acid treatm ent of dentin, as tubules are opened, thereby increasing the risk of bacterial infection and pulpal sensitivity. In opposition, Fusayama32has long m aintained that an effective seal can be obtained by first etching dentin with phosphoric acid, followed by sealing with resin and composite. As noted earlier, most current dentin bonding systems contain mild acids which, in effect, etch dentin. Recent clinical studies evaluated the use of acid cleansers on dentin in combination with dentin bonding systems and reported no pulpal problems.11'33-37 Gluma, Scotchbond-2, and older versions of Tenure—each contain ing a different acid conditionerhave been available for use in the United States for several years. As an indirect m easure of acceptance, the Complaint Reporting Program directed by the ADA Council on Dental Materials, Instrum ents and Equipm ent has not received many complaints regarding the use of dentin bonding systems. Caution is advised until additional Dr. Poweil is research is com assistant professor, pleted on the Department of Restorative effects of direct Dentistry, SM-56, etching of University of Washington, Seattle. dentin with phosphoric acid,38especially since this option has only recently been made available commercially to U.S. dentists (All-bond [all etch] and Clearfil Photo-Bond).
Histopathological evaluations using prim ates and cytotoxicity tests in vitro generally confirm the biological safety of several of the chemicals used in the dentin bonding systems.3WSM1With a new test for cytotoxicity, researchers recently reported th at there was decreased cellular activity in the presence of HEMA and glutaraldehyde42and decreased DNA and protein synthesis in the presence of unpolym erized BIS-GMA and UDMA.43The reported incidence of pulpal sensitivity is low, but one study has docum ented some sensitivity w ith the use of a dentin bonding system.19 If signs and symptoms of pulpal sensitivity occur after use of a dentin bonding system, first suspect microleakage as the cause. Air and cold sensitivity are common complaints with leakage since these stimuli can cause fluid m ovem ent in dentinal tubules, thereby causing pain. Seal the suspected area and check with air and water. If sensitivity persists, replace the restoration with an alternate filling material. CONCLUSIONS
To enhance the clinical success of restorations using a dentin bonding system: ■» provide excellent field isolation and m aintain clean surfaces; *« carefully follow all of the m anufacturer’s directions; ■» use a protective liner for deep lesions; and «■* provide preparation retention features when there is little or no enamel available to supplem ent adhesion. The best advice for dental practitioners is to be vigilant when using these systems. Monitor the restorations at each recall for symptoms of sensitivity and signs of leakage. Finally, report problems to the ADA Council on
Dr. Johnson is chairman of the ADA Council on Dental Materials, Instruments and Equipment and is associate professor,
Dental Mater ials, Instru m ents and Equipment, as use of dental restorative m aterials among practitioners represents the ultim ate clinical test of products.
Department of Restorative Dentistry, SM-56, University of Washington, Seattle 98195. Address requests for reprints to Dr. Johnson.
Publications of nam es of products does n o t imply endorsem ent by the Am erican D ental Association.
1. B uonocore MG. A sim ple m ethod of in creasing the ad h esio n of acrylic filling m aterials to enam el surfaces. J D ent Res 1955; 34:849-53. 2. Ten Cate, AR. Oral histology: developm ent, stru ctu re a n d form ation. St. Louis: Mosby; 1989:157. 3. ADA Council o f Dental M aterials, In strum ents and Equipm ent. ADA Guidelines for Dentin and E nam el Adhesive M aterials. March, 1991. 4. Bowen RL, Eichm iller FC, M arjenhoff WA, Rupp NW. A dhesive bonding of com posites. J Am Coll D ent 1989; 56:10-3. 5. Erickson RL. M echanism and clinical im plications of bond form ation for tw o d e n tin bonding agents. Am J D ent 1989; 2:117-23. 6. M unksgaard EC, Asm ussen E. Bond s tren g th betw een d e n tin a n d restorative resins m ediated by m ixtures of HEMA a n d glutaraldehyde. J D ent Res 1984; 63:1087-9. 7. S parrius 0 , G rossm an ES. Marginal leakage of com posite resin resto ratio n s in com bination w ith dentinal and en am el bonding agents. J P ro sth et D ent 1989; 61:67884. 8. Leinfelder KF. Using com posite resin as a posterior restorative m aterial. JA D A 1991; 122 (3):65-70. 9. Jo h n so n GH, Gordon GE, Bales DJ. Postoperative sensitivity associated w ith posterior com posite and am algam restorations. O per D ent 1988; 13:66-73. 10. Duke ES, Robbins JW, Howell ML, Sum m itt JB. Clinical evaluation of a d en tin adhesive system in cervical abrasions. J D ent Res 1991; 70:395. 11. Shintani H, Satou N, Satou J. Clinical evaluation of two po sterio r com posite resin s retain ed w ith bonding agents. J P ro sth et D ent 1989; 62:627- 32. 12. Council of D ental M aterials, In strum ents and Equipm ent. Clinical pro d u cts in dentistry. Chicago: A m erican D ental Association, 1990. 13. V anherle G, Lam brechts P, Braem M. An evaluation of d ifferent adhesive restorations in cervical lesions. J Pro sth et D ent 1991; 65:341-7. 14. Bastos P, Teixeira L, L einfelder K. Three-year clinical evaluation o f Scotchbond-2 as a d entinal adhesive. J D ent Res 1991; 70:395. 15. Wiley PM, D ennison JB, G regory WA. Clinical evaluation o f a cervical reten tio n groove in dentin bonding. J D ent Res 1991; 70:395. 16. Duke ES, Robbins JW, Snyder DE. D entin adhesive evaluation fo r restoring cervical abrasions lesions. J D ent Res 1991; 70:457. 17. v an Dijken JW. T he effect of cavity p retreatm en t p ro ced u res on d e n tin bonding: a four-year evaluation. J P ro sth et D ent 1990; 64:148-52. 18. M ount GJ. Restorations of eroded areas. JADA 1990; 120:31-5. 19. Powell LV, Gordon GE, Jo h n so n GH. Sensitivity of restored Class V abrasio n /ero sio n lesions. JADA 1990; 121:694-6. 20. Tyas MJ, B urns GA, Byrne PF, C unningham PJ, Dobson BC, W iddop FT. Clinical evaluation of Scotchbond: three-year results. A ust D ent J 1989; 34:277-9. 21. Edler TL, Krikorian E, Thom pson VP. FTIR surface analysis of d e n tin and d e n tin bonding agents. J D ent Res 1991; 70:458. 22. Isenberg BP, L einfelder KF. Efficiency of beveling
p osterior com posite resin preparations. J E sth et D ent 1990; 2:70-3. 23. Litkowski L, Sw ierczewski M, Durkee M, S trassler H. Root surface m arginal m icroleakage o f th re e d e n tin bonding agents. J D ent Res 1989; 68:207. 24. Chohayeb AA, R upp NW. Com parison of m icroleakage of experim ental and selected com m ercially available bonding system . D ent M ater 1989; 5:241-3. 25. H ansen EK, A sm ussen E. M arginal adap tatio n of p osterior resins: effect o f dentin-bonding a g en t and hygroscopic expansion. D ent M ater 1989; 5:122-6. 26. Crim GA. Influence of bonding agents and com posites o n m icroleakage. J P ro sth et D ent 1989; 61:5714. 27. H eym ann HO, Stu rd ev an t JR, B runson WD, W ilder AD, Bayne SC, Sluder TB. Two-year clinical d en tin adhesive study: cervical lesions. J D ent Res 1989; 68:186. 28. Prati C, Nucci C. M arginal gap, m icroleakage a n d sh e ar bond stren g th of adhesive restorative system s. J D ent Res 1989; 68:996. 29. H eym ann HO, Stu rd ev an t JR, Bayne S, W ilder AD, Sluder TB, B runson WD. Exam ining tooth flexure effects on cervical restorations: a two-year clinical study. JADA 1991; 122(6):41-7. 30. Soderholm , K-JM. Correlation of in vivo a n d in vitro perform ance of adhesive restorative m aterials: a rep o rt of th e ASC MD156 task group on test m ethods for the ad h esio n of restorative m aterials. Dent M ater 1991; 7:74-83. 31. Brannstrom M. Infection b en eath com posite resin restorations: can it be avoided? O per D ent 1987; 12:158-63. 32. Fusayam a T. Factors a n d prevention of pulp irritatio n by adhesive com posite resin restorations. Q uintessence In t 1987; 18:633-41. 33. Q vist V, Stoltze K, Qvist J. H um an pulp reactions to resin resto ratio n s perform ed w ith different acid-etch restorative procedures. Acta Odontol Scand 1989; 47:25363. 34. Bowen RL, Rupp NW, Eichm iller FC, Stanley HR. Clinical biocom patibility of a n experim ental dentineenam el adhesive for com posites. In t D ent J 1989; 39:24752. 35. B losser RL, Rupp NW, Stanley HR, Bowen RL. Pulpal a n d m icro-organism responses to two experim ental dental bonding system s. D ent M ater 1989; 5:140-4. 36. W endt SL, L einfelder KF. Clinical evaluation of a com posite resin /b o n d in g system . J D ent Res 1989; 68:233. 37. G w innett AJ, K anca J. M icromorphological relationship betw een resin and d en tin in vivo a n d in vitro. J D ent Res 1991; 70:457. 38. Duke ES. Adhesion and tooth-colored restoratives. C u rren t O pinion D ent 1991; 1:163-71. 39. W aknine S, Gable P, Schulm an A. Physicom echanical, adhesion a n d cytotoxicity characterization of eleven com m ercial d en tin adhesives. J Dent. Res 1989; 68:375. 40. Thom as CA, Reel DC, Dam m DD, M itchell RJ, Crim GA. T h ree d e n tin bonding agents in hum ans. J D ent Res 1989; 68:868. 41. Pam eijer CH, Stanley HR. H istological reactions in prim ates to a d e n tin bonding agent. J D ent Res 1991; 70:384. 42. Hanks CT, Parsell JR, Straw n SE, W ataha JC. Cytotoxicity of d e n tin bonding ag en ts w ith m onolayer and dentin diffusion. J D ent Res 1991; 70:384. 43. Straw n SE, Nassiri MR, Hanks CT, Cam eron MJ, W ataha JC, Craig RG. Bis-GMA and UDMA effects on cell m etabolism and cell cycle. J D ent Res 1991; 70:384.
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