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Esthetic dentistry is associated most oftenwith anterior restorative dental care. Es-thetic dentistry describes the effortsmade to restore teeth or prostheses with-out drawing attention to those changes.Esthetic dentistry also may enhance one’sappearance by improving contours ofteeth and gingival architecture or by pro-viding a brighter and more noticeablelook. Removable partial dentures(RPDs) are one aspect of esthetic restora-tive dental care that often is neglected.Due to the emphasis placed on estheticdentistry in the media and the advancesmade in this area during the past 15years, patients have come to demandprostheses that not only are comfortablebut also are less noticeable or more natu-ral in appearance. Many of the materials,techniques, and designs that may en-hance esthetics often are not taught to un-dergraduate dental students.1,2 Most den-tal schools are reducing the curriculumhours devoted to the clinical teaching ofremovable prosthodontics at a time whenthe need for RPDs is increasing.3

Implant dentistry may be used to re-place RPDs for some patients; however,financial, anatomic, psychological, ormedical considerations still require den-tists to understand how to create a treat-ment plan, design, and treat patients forremovable prostheses. Fabricating in-conspicuous implant restorations in theesthetic zone is challenging and often canbe performed more satisfactorily by uti-lizing RPDs. RPDs also offer a less com-plicated, less expensive, and time-savingalternative to implant treatment.

This article describes the estheticzone, how it should be evaluated, and

how it relates to the six partially edentu-lous dental categories that determineRPD treatment options.

The esthetic zoneThe term esthetic zone is used here to de-scribe the teeth and gingiva as they areobserved when a patient emits a heartylaugh; this laugh should be described,drawn in the treatment plan, or displayedin a photograph. This practice will allowdentists to avoid including unwarranteddisplays of clasps and other metal com-ponents in the treatment plan (Fig. 1).According to Preston, the esthetic zone iswherever the patient thinks it is.4 Eventhough the patient may not display metalwhile laughing, he or she still may believethat it can be observed. Dentists shouldalways communicate to patients whenmetal is to be used on the facial surfacesof teeth, even when the metal will not bevisible in the esthetic zone. Patientsshould have the opportunity to select al-ternative designs.

In 1984, Tjan et al demonstrated that87% of all patients had what was referredto as the average smile, in which the cervi-cal to incisal length of all maxillary ante-rior teeth was displayed to either the firstor second premolar.5 In light of this find-ing, dentists must be vigilant to eliminateclasps, metal proximal plates, spaces, orany obstruction in the esthetic zone forthe majority of individuals in their prac-tice. In that same study, 4.0% of the pa-tients displayed all of their maxillary an-terior and posterior teeth and theirattached gingiva. These patients are themost difficult to satisfy since all frame-work components and acrylic resin

flanges will be visible (Fig. 2). Dentistsmust pay attention to flange design (thatis, contours) in such cases; custom colorcharacterization also may be necessaryfor optimal esthetics. Finally, the studynoted that 6.0% of all patients displayedonly the maxillary anterior teeth from ca-nine to canine when smiling and may dis-play only part of those teeth and no at-tached gingiva (Fig. 3). Dentists can offerthese patients a wide array of RPD designconcepts that do not compromise the es-thetic zone.

Mandibular anterior teeth must be ob-served and described in the treatmentplan.6 Most patients display only 50% ofthe mandibular anterior teeth and 50% orless of the buccal surfaces of the premo-lars in the esthetic zone, while all occlusalsurfaces of the premolars usually are visu-alized. Dentists can conceal distractingRPD components in these patients butplanning is more complicated for the

Esthetic removable partial dentures Stephen Ancowitz, DDS, FACP

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This article provides information regarding the many ways that removable partial den-tures (RPDs) may be used to solve restorative problems in the esthetic zone without

displaying metal components or conspicuous acrylic resin flanges. The esthetic zone isdefined and described, as are methods for recording it. Six dental categories are

presented that assist the dentist in choosing a variety of RPD design concepts that maybe used to avoid metal display while still satisfying basic principles of RPDs. New

materials that may be utilized for optimal esthetics are presented and techniques forcontouring acrylic resin bases and tinting denture bases are described.

Received: March 4, 2004 Accepted: April 19, 2004

Fig. 1. A patient’s esthetic zone. Note thevisible clasps.

Fig. 2. A patient whose maxillary teeth andattached gingiva are visible upon smiling.

Fig. 3. A patient showing 50% of the anteri-or teeth from canine to canine.

DARTTwo hours of CDE credit

454 General Dentistry www.agd.org

many patients who don’t fall into this cat-egory. Patients display more mandibularteeth and gingiva as they age.7

Categories of partial edentulismThis article is divided into six categoriesof partial edentulism that are used to de-termine RPD treatment options.

Esthetic zone is not a concern and no need exists for abutmentretainersMost prosthodontists agree that a less-complicated approach to RPD treatmentis best.8 Any conventional claspingarrangement can be used, provided abut-ment teeth are not restored and the es-thetic zone does not display an RPD’scomponents. The patient must be in-formed that clasps will be placed on thefacial surfaces of teeth. These clasps willnot be visible when the patient smiles oremits a hearty laugh; however, they maybe visible if the lips are displaced forcibly.The patient should consent to this priorto treatment rather than after a frame-work has been constructed.

Infrabulge clasps are the most estheticof the conventional retentive clasps, of-fering dentists the best opportunity forplacing metal in less-conspicuous loca-tions.9 The foot of the infrabulge claspoften can be reduced for optimal place-ment. Ideally, these clasps should be

placed in the gingival third of a tooth andthe approach arm should not traversesoft tissue undercuts.

Wrought wire and cast circumferen-tial clasps are alternative designs for sur-veyed casts and appropriately recon-toured abutment teeth. The approacharm of these clasps should emanate fromthe middle third of an abutment toothand the retentive tip of the clasp shouldbe in the gingival third of the abutmenttooth. The proximal section of circum-ferential clasps should not emanate fromthe occlusal third of the tooth.10

When tooth-supported RPDs are pos-sible, a posterior anterior rotational pathRPD also should be considered. ThisRPD will allow conservation of toothstructure on posterior abutments whileavoiding facial and lingual clasps that canirritate the tongue and facial attachedgingival tissues (Fig. 4). The rotationalpath RPD design will be described in de-tail later in this article.

Esthetic zone is a concern and noneed exists for abutment retainersWhen the facial surfaces of abutmentteeth are visible in the esthetic zone, den-tists should consider other locations forretentive and/or bracing clasps. It is im-portant to distinguish between bracingand reciprocating clasps as part of aclasping assembly.11 Reciprocating aforce from a retentive clasp cannot be at-

tained practically without milling a castrestoration. Bracing is a term used to de-scribe what has been known convention-ally as a reciprocating clasp. The bracingclasp is used to prevent horizontal move-ment after the clasping assembly is seatedcompletely. Together with the retentiveclasp and rest of a clasping assembly, thebracing clasp satisfies a basic principle ofclasp design by encircling the abutmenttooth by more than 180 degrees.12

Using lingual retention to hide a re-tentive clasp often is an excellent option.If the abutment tooth has the appropriatecontour, a lingual undercut can be uti-lized for the retentive clasp that is not vis-ible. To satisfy the basic principle of en-circlement, bracing can be utilized on thedistofacial aspect of the abutmentteeth—together with rests, minor con-nectors, and tooth contacts (Fig. 5 and6)—without the unsightly display of abuccal clasp arm.13 The lingual retentionoption can be utilized for tooth-support-ed and tooth-and-tissue-supported res-torations.

When abutment tooth contours arefavorable, the posterior anterior rotation-al path RPD can be designed for lingualretention of the conventional clasping as-sembly (Fig. 7).

A Saddle-Lock RPD (Boos DentalLaboratories, Minneapolis, MN; 800.333.2667) avoids visible clasps by utilizinga distal facial undercut and a mesial rest.

Fig. 4. A PA rotational path of insertion RPD. Fig. 5. Framework with bracing componenton disto-facial of abutment teeth.

Fig. 6. A patient with lingual retention.

Fig. 7. A PA rotational path RPD with lingual retention.

Fig. 8. Saddle-Lock RPD with retainer armbeneath the proximal plate.

Fig. 9. Saddle-Lock RPD retainer beneaththe proximal plate in disto-facial undercut.

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This design is particularly suited fortooth-supported situations. One shouldbe cautious when using it for tooth-and-tissue-supported partial dentures, as thisdesign makes it difficult to establish guid-ing planes on abutment teeth and it maycompromise retention and stability of theprosthesis (Fig. 8 and 9).

The Rotational Path of Insertion con-cept is one of the most appropriate de-signs for this category.14,15 By rotating anRPD into position, dentists can avoid us-ing the standard number of clasps thatnormally are required. It must be re-membered that this design concept isused primarily for tooth-supportedRPDs, although there are a variety of waysto utilize this concept: posterior anterior(PA), anterior posterior (AP), and lateralpaths of placement. The first letter indi-cates the initial path of placement (utiliz-ing a rigid proximal component); the sec-ond letter indicates the segment of theprosthesis after rotation has occurred.This segment has a conventional claspingsystem.

The AP design used in Kennedy ClassIV situations (that is, partially edentulousspaces that cross the midline) is the mostpopular rotational path design. This de-sign eliminates clasps on the facial sur-faces of anterior teeth. Conventionalclasping can be utilized on both maxil-lary and mandibular posterior teeth that

are out of the esthetic zone (Fig. 10 and11). The author has used this concept toreplace first premolars and all maxillaryanterior teeth successfully.

When a limited space (for example,two central incisors) must be replaced,dentists should use a dental surveyor toensure that rests and rigid proximalplates are not prevented from seating onnatural teeth during the initial path ofplacement. Additional modificationspaces also may be replaced using thisconcept but the design is more complexand proper blockout procedures must beperformed to avoid interferences whenrotation occurs around abutment teeth(Fig. 12).

Although it is not always considered, aKennedy Class III with a modificationspace on the other side of the arch (bilat-eral tooth-supported partially edentulousspaces) is another method for utilizingthe AP rotational path RPD, precludingthe need for a visible clasp on a first orsecond premolar. A distal undercut onpremolars is used for the initial path ofplacement and the RPD is rotated with aconventional clasping system on the mo-lars (Fig. 13 and 14).

Conceptually, the lateral path of RPDinsertion is not different from the AP, ex-cept that a Kennedy Class III partiallyedentulous space (that is, one that doesnot cross the midline) is replaced with a

rotational path RPD that is rotated in amore diagonal direction. When conven-tional clasping is utilized, the initial pathis located more anteriorly and the con-tralateral side is rotated and positionedmore posteriorly (Fig. 15 and 16).

Flexite (Dentsply International, York,PA, 800.877.0020) is a translucent mate-rial that can be used to avoid metal dis-play; it also can be attached to metalframeworks, resulting in cross-arch stabi-lization and clasp encirclement. In recentyears, the author has experienced excel-lent clinical success using this materialwith cast frameworks (Fig. 17–19). Dueto Flexite’s lack of tensile strength, it mustbe designed with greater vertical heightand thickness than metal, which resultsin broader coverage of the abutmenttooth. The author designs Flexite claspsfrom the height of contour of the abut-ment tooth to the tooth gingival junction;most are 3.0–4.0 mm high and 1.5 mm

Fig. 10. An AP rotational path RPD designedto replace teeth No. 7–10.

Fig. 11. A patient wearing the AP rotationalpath RPD seen in Figure 10.

Fig. 12. An AP rotational RPD path withmodification spaces.

Fig. 13. Initial path of insertion on distal offirst premolar, left side.

Fig. 14. Initial path of insertion on distal offirst premolar, right side.

Fig. 15. Lateral path of insertion frameworkwith diagonal rotation.

Fig. 16. Lateral path of insertion RPD re-placing teeth No. 6 and 7.

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thick. Flexite is a relatively new materialand there is concern regarding its claspstrength and stability in the mouth overtime; as a result, this design would be thelast choice for achieving an optimal es-thetic result in this category.

Esthetic zone is a concern and theneed exists for abutment retainersAll of the above concepts can be utilizedwhen metal ceramic crowns are neededto restore abutment teeth in tooth-sup-ported situations. This section focuseson tooth-and-tissue-supported RPDs.Precision attachments are needed for thissituation to avoid clasps in the estheticzone. While there are numerous preci-sion attachments on the market, it wouldbe desirable for a dental practice to limitthe available attachments to two or three.Limiting the available choices will reducethe number of necessary componentsand result in greater efficiency and re-duced cost.

As stated previously, most prostho-dontists agree that a less-complicated ap-proach to RPD treatment is best. Howev-er, dentists must be prepared to placeprecision attachments on unrestoredabutment teeth when the esthetic de-mand is high. In these situations, the au-thor prefers to use extracoronal attach-ments, which are easier to fabricate and

more amenable to repair than intracoro-nal attachments. Extracoronal attach-ments also minimize tooth reduction andsatisfy stress-releasing or stress-directionprinciples that are required for tooth-and-tissue-supported RPDs (Fig. 20).16

Based on experience, the author prefersthe ASC-52 anterior protect system(Medesco Attachment/Implant Company,Laguna Hills, CA; 800.633.3726) and theERA-RV attachment (Sterngold Attach-ments, Attleboro, MA; 800.243.8942).17

The ASC-52 attachment is a universaljoint resilient extracoronal attachment,containing an iridium platinum receptaclethat is cast with the abutment crown (Fig.21). The receptacle is resistant to wear andavoids food retention due to its open de-sign. The ASC-52 is a spring-loaded dow-el that can be replaced easily. As a univer-sal joint, this attachment is unique becauseit does not require parallelism to function,it does not torque the abutment teeth, andit can be used with a single abutment sup-port when good cross-arch stability isachieved.18

One major advantage the ASC-52 sys-tem offers is the accuracy between the at-tachment and the metal ceramic crownthat is maintained during the processingof the acrylic resin. A brass processingdowel is used during the investing process(in place of the attachment ferrule) to se-

cure the relationship between the attach-ment and the crown. This brass dowelprevents damage during divesting by al-lowing the laboratory technician to re-move the metal ceramic crowns from themaster cast prior to investing; it also main-tains the exact relationship of the RPDframework and the crown (Fig. 22). De-livery of the RPD is accomplished withoutdifficulty and the need to correct an ill-fit-ting attachment with an auto-cured resinpick-up at delivery is reduced.

The ERA attachment has a plastic re-ceptacle that is connected to the wax-upfor the metal ceramic crown. For the ERAattachment to fit accurately into the recep-tacle, an excellent casting process is re-quired. Because the receptacle is madefrom the same metal as the crown, a met-al of sufficient hardness must be used tolimit wear. The manufacturer recom-mends a Vickers hardness of 200 and aminimum of 85,000 psi ultimate tensilestrength. Dentists must be aware of thismetal requirement and communicate thisto the technician, although metal recepta-cles will wear as a result of the plastic at-tachment regardless of the metal that isused.

Sterngold provides ERA attachmentsin a variety of sizes. The increased cir-cumference provides more retention inthe receptacle attached to the abutment

Fig. 17. Flexite clasp for tooth No. 6 at-tached to metal framework.

Fig. 18. Full-face view of Flexite clasp ontooth No. 6.

Fig. 19. A patient with a Flexite clasp displaying her esthetic zone.

Fig. 20. Stress release using the ASC-52 at-tachment is demonstrated.

Fig. 21. A platinum iridium receptacle isplaced into wax-up of abutment crown.

Fig. 22. Waxed-up cast prior to investing,with abutments and castings removed andbrass dowel replacing ASC-52 attachment.

September-October 2004 457

tooth, which compensates for metal wear.The increased circumference of these at-tachments is color-coded for ease of se-lection. Sterngold also recommendspicking up this attachment in the mouthwith an auto-cured acrylic resin duringthe delivery of the RPD by making a win-dow through the lingual flange of theacrylic resin base (Fig. 23).

An alternative technique involvesplacing an analog in the impression byusing a black processing male (Fig. 24).This technique makes it possible for thelaboratory to connect the attachmentduring the processing of the acrylic resinbase rather than forcing the dentist to doso at chairside. It is critical that this ana-log is positioned properly into the im-pression; positioning the analog inaccu-rately, coupled with the resiliency of theimpression material, could result in anunsuccessful seating of the prosthesis atdelivery.19 If seating is unsuccessful, themisplaced attachment must be removedand picked up in the mouth as describedpreviously. Despite these concerns, thisattachment is relatively easy to fabricate,repair, and maintain when used properly.

Height concerns and impression pro-cedures are general considerations com-mon to both attachments. Accurate diag-nostic mountings are essential whenprecision attachments are used. Thespace between the proximal gingiva andthe opposing tooth is critical for the useof these attachments; this distance can bemeasured using diagnostic casts (Fig. 25).The ASC-52 requires a minimum verticalheight of 5.5–6.0 mm, while the ERA re-quires 4.50 mm (slightly more if a 0.3 mmmetal housing is used).

The author has found the Turbyfilltechnique to be useful for making im-pressions utilizing the ASC-52 and theERA.19 This technique involves pickingup the abutment crowns from the mouth

and making them an integral part of themaster cast. The RPD framework ismade from this cast to attain a high de-gree of accuracy when relating the RPDframework to these crowns. The authorprefers making a one-piece border mold-ed impression of the teeth and the eden-tulous areas, utilizing a custom tray witha polyvinyl siloxane or polyether impres-sion material. In the mandible, bordermolding the alveololingual sulcus is par-ticularly important to ensure more accu-rate placement of the inferior section of alingual bar or plate. Border molding isnot necessary for areas where a metalcomponent or acrylic resin flange willnot be present. To avoid locking the trayin the mouth, it is important to block outthe gingival embrasures of any naturalteeth prior to making the impression.Impressions made in this manner pre-clude the use of an altered cast procedureand are equally accurate.20

Esthetic zone is not a concernand loss of a critical abutmenttooth existsThe upper lip becomes longer with age,making it possible to use more of thetooth surface without displaying clasps.7,21

Another esthetically satisfactory methodcan be utilized when one cannot observethe gingival 20% of the existing teeth and

the patient is missing a canine or anothertooth critical for adequate stability or re-tention. This method involves the Swing-Lock RPD (Swing-Lock, Dallas, TX;214.361.8263), which is not often thoughtof as an esthetic RPD design. The Swing-Lock makes it possible to locate retentiveterminals on abutment teeth that are morecervical than can be accomplished ordi-narily using conventional clasping mecha-nisms.21 Generally, 6.0–8.0 mm of at-tached gingival space is necessary forplacing a labial bar. High labial frenum at-tachments could interfere with the labialbar placement and are a concern when us-ing this design concept; a frenectomy orfree gingival graft sometimes is required toplace the frenum in a more apical posi-tion.22,23 Based on the author’s experience,the free gingival graft produces a morepredictable and stable result than thefrenectomy.

The Swing-Lock prosthesis does notneed retention for every existing tooth;two or three vertical clasp tips or lugs issufficient for retention. If one or two teethdisplay the entire facial surface from cervi-cal to incisal, a clasp can be eliminatedhere and another tooth that allows formore inconspicuous placement may beutilized. It also is possible to place clasptips at the line angles of teeth rather thanin the center of a tooth (Fig. 26 and 27). In

Fig. 23. Window made in acrylic resinflange prior to picking up the attachment.

Fig. 24. ERA analogs placed into abutmentcrown impressions prior to pouring stone.

Fig. 25. The available space between oppos-ing teeth and planned precision attachmentabutment tooth gingiva is measured.

Fig. 26. A Swing-Lock prosthesis demon-strates retention on selected teeth and at aline angle of tooth No. 8.

Fig. 27. The patient in Figure 26, demon-strating clasp tips placed out of the estheticzone.

458 General Dentistry www.agd.org

the author’s opinion, the Swing-Lock par-tial denture is one of the most underuti-lized and beneficial designs for RPDs.

Esthetic zone is a concern and lossof a critical abutment tooth existsThis category does not allow the use ofconventional RPD designs. Extracoronalprecision attachments can be used onmaxillary Kennedy Class IV situationsusing premolars as abutments (Fig. 28and 29). Caution is necessary when pre-cision attachments are used on anteriorteeth to avoid overcontouring abutmentcrowns and interfering with the opposingocclusion. In these situations, the authorhas had success using Flexite clasps andFlexite major connectors with full palatalcoverage (Fig. 30 and 31). Making palatalplate major connectors with Flexite ma-terial seems to provide adequate stiffness.

Another way to treat patients in thiscategory involves using implants for se-lective replacement of these lost, critical-

ly needed abutment teeth. Implants canbe used as abutments to assist in retain-ing a prosthesis. A variety of stud attach-ments are available as abutments for im-plants capable of retaining one or moresections of the RPD. The author has hadexcellent clinical success using the LocatorImplant Attachment System (Zest An-chors, Inc., Escondido, CA; 800.262.2310).While conventional clasping would not beplaced in the esthetic zone, it may be uti-lized in other areas of the arch (Fig. 32and 33).

Utilizing RPDs for esthetic purposesbecomes very difficult when patientshave four or fewer teeth remaining in anarch. It is difficult to develop acrylic resinflanges adjacent to natural teeth withoutcreating unattractive spaces and shadows.Metal proximal plates often are visible inthe esthetic zone. The retention and sta-bility of an RPD prosthesis also may becompromised. When this situation oc-curs, overdenture prostheses should be

considered for areas where the dentist hastotal control of the placement of teethand denture base flanges.24 For themandible, it would be beneficial to con-sider stud or bar attachments to enhanceretention and stability for the overden-ture prosthesis.

Esthetic zone is a concern andflange design is importantWhen treatment planning for a patientwho falls into the small (4%) category ofpatients who display all of their anteriorteeth and attached gingiva, it is necessaryto pay attention to the denture flanges ofRPD prostheses. It must be understoodthat acrylic resin flanges of RPDs are usedto replace missing bone. The flanges ofmany RPDs are overcontoured in relationto the adjacent teeth and alveolar sup-port. In the esthetic zone, natural teethoften require replacement with tooth-supported prostheses.

Alveolar defects vary from person toperson. When adjacent natural teeth arepresent, the supporting alveolar structureshould be used as a guide for blendingacrylic resin to develop the edentuloussoft tissue. Inaccurate placement of toothgingival junctions of the artificial teethrelative to the natural teeth leads to thick,bulky denture flanges that replace hardand soft tissue apically and proximally, re-sulting in readily visible esthetic compro-mises. Occasionally, it is possible to re-place the artificial tooth with little or no

Fig. 29. A patient wearing the attachmentfrom Figure 28.

Fig. 30. Flexite prosthesis with full palatalcoverage and Flexite clasp on tooth No. 8.

Fig. 31. A patient wearing the Flexite pros-thesis from Fig. 30.

Fig. 32. Locator stud attachments placed onteeth No. 12 and 15 for RPD retention.

Fig. 33. RPD with plastic locator attach-ments.

Fig. 34. Artificial teeth with minimal inter-proximal tissue replacement between theteeth.

Fig. 35. A patient wearing the RPD fromFigure 34.

Fig. 28. An ASC-52 precision attachment uti-lizing teeth No. 6 and 13 as abutments.

September-October 2004 459

denture flange (Fig. 34 and 35). Theproximal and apical flanges of acrylicresin on tooth-supported RPDs should beknife-edged rather than rounded. Thisedging will prevent shadows and allow thecolor of the soft tissue to blend and evenshow through in these critical areas. Italso is important to control the proximalcontours of teeth in these circumstances,since bell-shaped teeth with proximal gin-gival undercuts will create a dark spacebetween the adjacent artificial tooth andthe flange of the prosthesis.4 Proper use ofa dental surveyor is important for over-coming these esthetic concerns.

Tinting or characterization tech-niques are critically important for pa-tients whose attached gingival tissueshave melanin pigmentation or colorationthat does not match the available colorsof acrylic resin. However meticulous thedesign and fabrication, all could be lost ifdenture base tinting is disregarded, espe-cially for the 4% of patients who show allof their natural teeth and attached tissue.

Characterization of acrylic resins is asimple technique that involves gently sift-ing colored powder and liquid into thedenture mold prior to processing theacrylic resin (Fig. 36 and 37). Acrylicresin is available in a variety of colors,which can be used individually or mixedto arrive at a desired color (Kay-Dental,Kansas City, MO; 816.842.2817). Photosof these patients may be given to a dental

technician who is familiar with this tech-nique; the patient also may go to the den-tal laboratory during the processing ofthe acrylic resin base.

SummaryThe esthetic zone should be evaluated aspart of the clinical findings. The dentistshould photograph, diagram, or describethe esthetic zone in writing for reference.Thorough esthetic evaluation will servethe dentist through all fabrication proce-dures and help to avoid costly mistakes.RPD designs, new materials, adjunctivetechniques to help characterize denturebases, and implants that can replace miss-ing critical abutment teeth mean that den-tists no longer have to invade the estheticzone with unsightly RPD components.

DisclaimerThe opinions expressed in this article rep-resent the sole views of the author. Theauthor has no commercial interest in anyof the manufacturers listed in this article.

Author informationDr. Ancowitz is the program director,prosthodontic residency program, WestLos Angeles Veterans AdministrationMedical Center, and an assistant clinicalprofessor, Department of Prosthodon-tics, UCLA School of Dentistry. He alsois a continuing education faculty mem-ber for postgraduate programs in Esthet-ic Dentistry at the State University ofNew York at Buffalo, the University ofMinnesota in St. Paul, the University ofCalifornia at San Francisco, and the Uni-versity of Florida at Gainesville.

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20. Leupold RJ, Flinton RJ, Pfeifer DL. Com-parison of vertical movement occurringduring loading of distal-extension remov-able partial denture bases made by threeimpression techniques. J Prosthet Dent1992;68:290-293.

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To order reprints of this article,contact Donna Bushore at 866.879.9144, ext. 156or dbushore@fostereprints.com.

Fig. 36. An acrylic resin monomer placedon polymer in lower half of denture flask.

Fig. 37. An example of denture base tintingapical to teeth No. 8 and 9.