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Maintaining Esthetic Restorations inttie Periodontal Practice

Michael K. McGuire. DDS'Lynn Miller. RDH"

Esthetic dentistry comprises one of the most rapidly growing segments ofaur profession, and patients receiving tNs type of treatment are oftenmaintained on an aiternating schedule, improper maintenance care canquickiy destroy many of fhese restorations. This artide witi serve as aresource for dentai prafessionais who wish to offer these speciai patientscustomized maintenance care. (Int J Periodont Rest Dent 1996:16:231 -239.)

'Private Practioe, Houston, Texas, Assistant Clinical Professor.University of Texas Dental Branch, Houston, Texos; and AssistantCiinical Piofesso:, University of Texos Heaith Science Center DentalBronch, San Antonio, Te/as.

••lîegistered Dentoi Hygienist and Consultont, Austin, Texas.

Repiint Requests: Dr Michael K. MoGuire, 3400 South Gessner, No.102, Houston, Texas 77OÓ3.

Potients with esthetic restoro-tions have speciai maintenanceneeds that otten are not ad-dressed during routine perio-dontol supportive treatment.Absolute protection of cosmeticrestorations must be assuredduring maintenance visits, yetthe expiosion of new vorieties ofdentai materials renders thetosk of devising a oustomizedmointenance routine a time-consuming and compiex effort,even for the weii-informed den-tal professional. Nevertheless,the responsibility for maintainingthe esthetic restorotion falls oneoch member that enters intothe maintenance program—notonly on the restorotive dentist,but the potient ond periodontistas weil. Periodontai protessionaiswhose primory focus is thepreservotion of the supportingstructures of the teeth needwell-organized informationabout the latest esthetic dentalmoteriois and their mainte-nance requirements. It is ourintention that this orticie serveas that resource.

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Fig 1 indirect resin veneers wrapatound ti^e iooth to reinforce andiengthen the tooti^. The morgin that isparticularly vulnerable to maintenancecare will be found an the Incisai half ofthe lingual surface.

Esthetic restorative materialsand terms

A fhorough undersfanding offhe foiiowing materials andterms will assist the periodontaiprofessionol in devising a suc-cessfui maintenance program;

1. Resin: on organic poste,filled or unfiiied. Fiiled resinscontain giass or silica fillerparticles; unfiiied resins con-tain no fiiier particies andare used to bond porcelainand indirect veneers ond forfissure seaiants,

2, Composites: filled resins thctcon be chemically cured,light cured, or light acti-vated and chemicallycured (dual cure). The threetypes of composites arehybrids, micrcfiiis, and smallparticle composites, (Smailpartlcie composites are nolonger being used clinically,but may be found in existingrestorations,)

3. Hybrid composites: a mix ofmicrofill and macrofiii parti-cies suspended in resin thatcan be used in both poste-rior and anterior teeth,

4. Microfill composites; com-posites thot hove very finelyground silica for fiiier mafer-iol and may be polished tovery high iuster, but tend tobe brittie. They ore usuaiiyreserved for anterior feefh.

5. Bonding: physical or chemi-cai adherence of a restora-five materiai to enamei,dentin, or onother restora-tive material,

6. Direct resin veneers; com-posite material opplied tothe tooth's facial or buccalsurface. Direct veneers stainmore easily than indirectveneers, lose their onatomyfaster, ond have iessresiiience to thermocycling.

7. indirect resin veneers: com-posites fobricated from amodei at prepored teeth,then baked at high temper-

atures. They are more densethan direct veneers and thusless iikeiy to stain, indirectresin veneers can wraporound the incisci edge tocover one third of fhe iinguaisurface. They ore bondedwith resin cemenf (Fig 1).

8. Ceramics; compounds con-tdining o metai (one ormore) pius a nonmetal (usu-aiiy oxygen) which yield sta-ble substonces that arestrong, hard, brittle, ond inertconductors of thermal andelectric energy

9. Porceicin veneers; thinceramic moteriol bondedto facial or buccal surfacesof teeth.

Maintenance of estheticrestorations

A gênerai discussion of themaintenance of ceramic dndcomposite restorations will pre-cede a detoiied description ofsuggested sequentiol steps tobe used in routine cleaningand poiishing. The outhors havesummarized these steps in aflow chart (Fig 2).

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Maintenance of Ceramic and Resin Restorations

Always use curettes to débride the restoration.Polish 15 lo 30 seconds with porcelairî polishing paste when onlyporcelain ¡s exposed. Polish with aluminum oxide paste on resinrestorations or on porcelain restorations when resin cement orcementum is exposed.Carry paste interproximally with floss and polish.Rinse and inspect.

If there is no stain, go to step 5.

Light stain

îLight stain Light stain

Porcelain

A. Polish for 30 secondswith CéramisteUltracup (Shofu).

B. Polish for 30 secondswith Ultracup II.

C. Begin with UilraCéramiste M i di-pointsand graduate to Ultra il.Polish with each lor 30seconds.

D. Polish with porcelainpolishing paste.

Resin cement

A. Polish for 30 secondswith aiuminum oxidepaste.

B. Smooth with mediumcarbide blade mter-proximal angle (Profin).

C. Protectgingiva.Applycomposite whiteningagent. Polish for 30 to60 seconds.

Composite restorations

A. Polish occlusal withpear-shaped finisherfollowed by a rubberpolishing instrument.

B. Polish facial andiingual with a oup-shaped polishinginstrument.

C. Polish with aluminumoxide polishing pastefor 30 seconds.

Heavy stain on porcelain, composite restorations, and resin cement

A. Medium-grit aluminum oxide disk 10 to 15 seconds.B. Fine-grit aiuminum oxide disk 10 to 15 seconds.C. Extra fine aluminum oxide disk 10 to 15 seconds.D. Polish porcelain with porcelain polishing paste. Polish composite

restorations and resin cement with aluminum oxide polishing pasteand carry interproximally with floss.

Interproximal stain

Aluminum oxide finishing strips. Start with the finest grade and graduateto the next coarsest grade until stain is removed, then reyerse the pro-cess and graduate to the finest grade until the restoration is smooth.

5. Appiy sodium monofluorophosphate fluoride.

Fig 2

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Ceramic restorations

Ceramic restorations are themost susceptible to stain in twomain areas—the resin cementiine and areas on the restora-tion where the dentist wasrequired to "finish in the mouth,"For porceldin veneers, oniymeticulous homecdre and pro-fessionai maintenance will pre-vent staining. The exposed resincement at the margin wiii wearat a higher rate in ceromicinlays and onlays than in theporceiain, and will eventualiyiead to open margins that oisorequire meticulous mainte-nonce. Careful polishing is espe-cially important for cast ceram-ics such as Dicor (Dentspiy) thathave color appiied to the sur-face.

Composite restorations

Maintenonce success ot acomposite depends on its abil-ity to keep the marginai seaidetermined by the initiai adap-tation of the materiai to thecavity walls of the preparation.During the iife of the compos-ite, thermooycling and pluckingot filier particies resuit in voidsand tags in the materiai, whichiead to ploque build-up andsubsequent softening of thecomposite. The best mainte-nance regimen for compositesincludes polishing with aiu-minum oxide poiishing pasteevery 3 or 4 months,

Microfiii composites requirecareful treatment, The ciinicianmust first iocate the tooth-microtill margin to avoidscratching or ditching this area,In restorations of frocturedanterior teeth or diastema cio-sures in which only part of thetooth is microtlli composite, thewhole tooth shouid be treatedas though it were composite.The entire tooth should be pol-ished with aluminum oxide pol-ishing poste, or, for teeth withexcess stain, rubber poiishingcups or aiuminum oxide disks.

Posterior composites, chai-lenged further by masticatorystress, are at risk tor increasedsurface roughness. Annual poi-ishing with rubber aluminumoxide-impregnated polishingcups, discs, or points is recom-mended.

Diífereníiation of ceramics fromcomposite restorations

To differentiate o porceloinrestoration from composite orenamel, gentiy run an expiorerover the tooth's surface. Thecomposite restoration wiii teeisofter than enamel's hard sur-face. When an explorer glidesover a porcelain veneer, a"scratchy sensation," which isunlike composite or enamei,can be feit and heard, A porce-lain veneer's hardness mimicsenamei and is much harderthan the surface ot compositerestorations (Fig 3), Proper main-

tenance procedures dependon this differentiation, becauseporcelain is polished differentiythan composite material (Figs4a and 4b).

Ciinioai tip. Label the chartwith a "Poroeiain Veneer" or"Composite Veneer" olert.

Routine oieaning and poiisi^ingofceramio and compositerestorations

Ciinioai tip. Use at least 2-powermagnification for routine cieon-ing and poiishing. Porceloin ondresin cements can develop tinycracks that are difficult to seewithout magnification. In addi-tioh, magnification helps theclinician detect the margins ofthese restorations,

1, Débride with curettes,which offer the tactiie sensi-tivity necessary for the ciini-cian to clean porcelain andcomposite restorations with-out scratching the material(Fig 5), Hand sealers andsonic or uitrasonic scdierscan scratch the glaze ofporcelain and composites,'Ciinicai tip. When porceloinhos become roughenedthrough occlusal wear, pol-ish with an Ultracup il(Shofu) for 15 to 30 secondsprior to moving on to Step2.

2. Poiish porcelain veneerswith porcelain polishingpaste, unless resin cement

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Fig 3 me central incisor is o microtiliindirect veneer: the lateral is a porce-ioin veneer. Tootile sensitivity is neces-sary to distinguish one from the other.This differentiation is essentiot in propermaintenance care.

Fig 4a Froctured maxiilary centrai ondlaterai incisors

Fig 4b Same teeth as in Fig 4a follow-ing restoration with microfili composites.Note how difficult it is to identity therestoration and how quici

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Removing stain

Removing light stain onporoelain

This technique is to be usedwhen the parcelain, not theresin cement, is stoined. Por-celain rubber poiishing instru-ments, slightly harder thancomposite rubber poiishinginstruments, come in threegrades. The two finest are usedin this prooedure.

1. For faciol or linguoi surfaces,start with the rubber pciish-ing instruments (CéramisteUltracup) which are espe-cially helpful for marginswith light stain. Use the cupon a dry tooth for 30 sec-onds. Carefuily inspect thetooth visuaily and with onexplorer for stain ond rough-ness.

2. Polish with the Uitrocup li for30 seconds,

3, For lingual, incisai, or oc-clusal surfaces, sfart wifh theCéramiste Uitra Midi-points(Shofu), Begin with the Ultraûhd graduate up to theUltra II. Polish with each for30 seconds.Clinicoi tip. Always use light,uhiform strokes with rubberpolishing instruments. Toomuch pressure can over-heat the restoration and thetooth.

4, Appiy the porceiain polish-ing paste and polish thor-oughly for 30 seconds with a

rubber cup, If strips or diskswent interproximally, carrythe paste in those areaswith fioss.

5. Dry the tooth and carefullyinspect the restoration. Youare finished if there is nostain.

Removing light stain on resincement

Stain on the resin cement sur-rounding the porceiain veneercan be removed by compositewhitening agents and interprox-imai polishing angies (Profin,Weismann Technology) (Fig 8).

1, Thoroughiy cieon the entirearea with a rubber cup andaluminum oxide polishingpaste.

2. Remove composite tagsand smooth with a mediumcarbide blade on the Pro-fin instrument. Check forsmoothness with an explorer(some of the stoin may beleft). Rinse thoroughly

3, Protect the gingivo with agingivai protectont (Brite-Smile), Apply compositewhitening agent (AoceiAdvantage, Brite-Smile) witha cotton tip appiicotor.Polish with rubber cup for 30to 60 seconds. Rinse thor-oughiy

4. Polish resin cement withaluminum oxide polishingpaste.

Removing light stain on com-posite restorations

The following maintenance pro-cedures are used it there is stainon the margins or line anglesafter polishing with aluminumoxide poiishing paste. Com-posite rubber poiishing instru-ments inoarporate aluminumoxide into a soft rubber and oreavailabie in o voriety of shapeseasily adaptable to every sur-face. These save an extra step(compared to the disks) be-cause they come in only twogrits: finishers and poiishers. Thefinishers remove surface irregu-iarities, tags, and light stoin. Thepaiishers ieove the restorationas smooth os possibie.

1. A pointed or pear-shopedfinisher shouid be used forccciusGl surfoces and em-brosures. Next the polishingpoint is used to leave therestoration as smooth as pos-sible. Use G iight, uniformstroke. Too much pressurecan overheat the restorotionand the tooth. Rinse thor-oughiy Carefully examinethe tooth to ensure a smoothsurface that is free of stain.

2. For facial surfaces, use thecup-shaped instrument.Cups con also be used ohthe iinguai surfaces of pos-terior teeth,

3. Poiish again for 30 secondswith aluminum oxide poiish-ing poste and floss interprox-imaiiy. Rinse weii with woter.

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Removal of medium stain

Medium stain or roughness canbe removed from the interprox-imal aspects of porcelain re-storations, on composite restor-ations, and on resin cementwith aluminum oxide polishingstrips. Carefully insert the piasticmiddie portion of the strip(which is not abrasive) into theembrasure so the contact isnot opened. Start with thefinest grade. If this does nofremove fhe stoin, groduateto the next coarsest grade.Continue this process until thestain is removed. Then gradu-ate back to the finest grade toieave the restoration as smoothas possible. The coarsest gradeof the strip shouid not be usedfor stain removai as it Cdn openthe contact or embrasure.

Removai of heavy stain

This technique is often usedwhen porcelain and compositerestoratians and resin cementare stained and ddmagedfrom previous use af an air-abrasive polisher, a sonic oruitrasonic seaier, or a coarsepolishing paste.

Heavy stain found outsidefhe proximal areas, includingembrasures, can be removedwifh aiuminum axide disi

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Fig JOCieff) Note the pitted sur^ce ofthe microÊI veneer k>itawing the use otan air-powdei abrasive instrument.

Fig 11 (right) The scratched andabraded surface of the microtill com-posite was caused by a hord tooth-brush with baking soda and hydrogenperoxide.

Figs J2a Note the inflomed periodon-tium associated wltt) the resin veneers.Plaque causes the margins of therestoration to break down further, andthis in turn irritates the periodontium.

Fig 12b Periodontium returns to healthafter the removai of the veneers andinstitution of proper homeoare procé-dures.

Fig 12c Same area as in Figs 12a and¡2b after placement of properiy ccn-tcured poroeiain veneers.

improper mainferiance ofparcelain and compositerestarations

The following common mainte-nance procedures can jeopar-dize the initial smooth surfaceof o restoration:

1, Coarse polishing poste mayroughen, scratch, ond dullthe surface glaze of porce-loin ond composites,-'

2, Sonic or ultrasonic sealerscan scrotcii the surfoceand "pluck" eut filler parti-cles ot o composite,^ Theycan also remove significant

amounts of resin oementand break the bond of theveneer to the tooth.Air-powdor abrasive instru-ments can scratch and pitthe surfoce of compositerestorations (Fig 10) andeven remove port of thecomposite material.'' Theycan break the resin bond ofporceiain veneers and resultin pitting, stoining, ond iossof luster.5A hard toothbrush andabrosive toothposte mayabrade composites (Fig11),"

5. Never use acidulated phos-phate fiuoride; it can etchthe veneer ond resin,^increase the surface rough-ness, and reduce surfaceluster The result Vî iil occeier-ate pitting and staining.^''

Home care fallowing parcelainand composite restoratiotis

Composite resins and the resincement around porceiainrestorations can be damagedby piaque cr by an abrasivetoothbrush and toothpaste,ieading to softening, pitting, and

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scratching of the restoration.Accelerated staining, increasedplaque retehtion. and marginaileakage wiii resuit (Figs 12a to12o),

A conscientious regimen ofdaily fiossing and plaque con-trol with a soft toothbrush is onecessary part of home care.

Antimicrobial rinses

Though antimicrobiai rinseshave become a popular ad-junct for treating periodontaldiseases, two side effects war-rant carefui consideration. First,most rinses contain high con-centrations of alcohoi, whichcan sotten bonding and leadto further piaque retention,staining, and microleokage,Second, some rinses are inher-ently staining. Both risi