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Over the last few years, the evolution of restora-tive materials has taken an important step.1The introduction of zirconia and pressedceramics has provided a new perspective on thetooth-supported prosthesis.2,3 However, the pre-dictability of zirconia materials when used for im-plant-supported prostheses is still undetermined.This article aims to analyze when these new mate-rials can be predictably implemented in implant-supported restorations.

ZIRCONIA IN IMPLANT-SUPPORTED RESTORATIONSBased on clinical experience, there is no doubtthat zirconia is a viable material for restoring natu-ral abutments. But what about implant-supportedabutments? The differences between implantabutments and natural abutments are obvious.However, in recent years it has been attempted toconvert implant-supported abutments into tooth-like abutments.4,5 In so doing, ceramic materialshave been applied to the attachments, thereby ap-proaching the color and emergence profile of anatural abutment.

Zirconia has been used to produce direct implantabutments, thus taking advantage of the materialsfracture resistance. However, what clinical evidencedo we have that this is a viable solution? Directloading of an implant with a zirconia structure doesnot guarantee durability. On the other hand, materi-als such as gold-palladium, iridium, or titanium are

1Barcelona, Spain.2Private Practice, Barcelona, Spain.3Private Practice, Valencia, Spain.4Sabadell, Spain.

Correspondence to: Mr August Bruguera, C/ Vilamari,56 local 1, Barcelona 08015, Spain. E-mail:[email protected]

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NEW MATERIALS IN IMPLANTOLOGY

Augusto Bruguera, CDT1

Erika Tllez, DDS2

Albert Vericat, DDS3

Javier Moreno, CDT4

Xavi Balmes, CDT1

98-108_BRUGUERA_ABA:129_SHOR_v5 1/16/09 1:26 PM Page 98

2009 BY QUINTESSENCE PUBLISHING CO, INC. PRINTING OF THIS DOCUMENT IS RESTRICTED TO PERSONAL USE ONLY. NO PART OF THIS ARTICLE MAY BE REPRODUCED OR TRANSMITTED IN ANY FORM WITHOUT WRITTEN PERMISSION FROM THE PUBLISHER.

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well documented to provide durability.4 Therefore,until clinical evidence is available to the contrary, it isnecessary to attach a transepithelial connector ele-ment between the implant and zirconia. This will en-sure that the restoration will not harm the implant. Itis important to remember that when a high-strengthmaterial is used to load a material of lesser strength,a superficial distortion will occur in the weaker mate-rial. This means that if a load is applied to an im-plant (which has a lesser flexural resistance) with azirconia superstructure (which has a greater flexuralresistance), the implant will always suffer the distor-tion. Figure 1 shows the use of a zirconium abut-ment with a titanium connector (Biomet 3i, PalmBeach Gardens, Florida, USA) to restore a central in-cisor. This type of abutment allows for the use of ce-ramic, which is an effective material for restoring ananterior tooth (Figs 2a and 2b). On the other hand,the ceramic walls of the abutment allow for loadingwith a pressed ceramic crown and cementing withadhesive cement.

ZIRCONIA IN LONG-SPANRESTORATIONSAlthough small anterior restorations still representan esthetic challenge, technically speaking suchrestorations are not greatly complex. When con-fronted with the challenge of an implant-sup-ported rehabilitation with a metallic superstructure,maintaining passive fit after firing the ceramic willalways be a challenge. In the authors experience,this often leads to the need for adjustments. Onesolution to this problem is the cemented prosthe-sis. However, when fabricating long-span restora-tions, screw-retained prostheses are often pre-ferred due to their ease of removal andmodification. In this sense, zirconia is a reliable ma-terial because the expansion and contraction thatoccurs while in the oven is linear. Therefore, ifgood passive fit is achieved prior to firing, it willnot be altered by the glazing process.

Fig 1 Abutment with a titanium connector and zirconiasuperstructure.

Figs 2a and 2b Ceramic is placed on the abutment(e.max Ceram, Ivoclar Vivadent).

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CASE REPORTThe patient presented with periodontal problemsincluding the loss of more than two-thirds of thebone support. For this reason, it was practical toperform the extractions and immediately place andload six implants at the same surgical appointment.Once the implants had osseointegrated, the finalimpression was made to fabricate the diagnosticwaxup and provisional restorations, with the goal ofobtaining a proper emergence profile (Fig 3). Thediagnostic waxup is always more useful when it canbe tried in the patients mouth, because while func-tion is easily evaluated using an articulator, it is

often difficult to evaluate esthetics without observ-ing the impact of the waxup within the facial ex-pressions of the patient (Fig 4). The objective of thetry-in is to locate the incisal contours as they relateto the lips. Thanks to the waxup, any modificationscan be carried out quickly and easily.

Initially, the intention was to obtain a secondprovisional restoration from the diagnostic waxup.6,7

However, because this provisional would have tobe removed repeatedly from the patients mouth tomake modifications and mold the emergence pro-file, it was decided to sacrifice esthetics and use an-gled abutments (Fig 5), despite being unable toobtain proper incisal contours (Figs 6 and 7).

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Fig 5 Angled transepithelial attachments wereplaced to correct the facial emergence of the abut-ments.

Fig 6 Screw-retained provisional restoration.

Fig 7 The provisional restoration was placed eventhough the correct incisal contours had not been ob-tained.

Fig 4 Diagnostic waxup in the patients mouth.Fig 3 A final impression was made once the six im-plants had osseointegrated.

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Once the gingival contours are molded, thedefinitive framework can be fabricated. In thiscase, it was decided to use cemented restorationsin the anterior region and screw-retained restora-tions in the posterior region to better ensure anacceptable emergence profile.

For the preparation of the anterior abutments, apressed ceramic technique was used. Loading theabutment with pressed ceramic is not a novel con-cept; however, manufacturing these abutments frompressed ceramic is a new technique. Pressed ce-ramic does not have sufficient fractural resistance tobe used as an abutment; therefore, a metallic inter-nal structure is necessary. Pressed ceramic providesa tooth-colored restoration with translucency and

light refraction very similar to that of a natural tooth(Figs 8 and 9).8,9 Further, pressed ceramics fracturalresistance of 440 MPa and reduced costs make it amaterial that should be strongly considered.

To restore an anterior tooth with a pressed ce-ramic abutment, titanium or gold-palladium mustbe added to provide additional support. The abut-ment will have to be opacified as if it were goingto be baked (Fig 10a). One of the advantages ofpressed ceramic is the precision of the lost-waxtechnique. If care has been taken to produce aprovisional restoration with an emergence profilethat maintains healthy tissue, that same emer-gence profile should be replicated by the defini-tive abutment. To ensure the replication of the

8 9

Fig 8 Ceramic restorations must imitate the opales-cence and translucence of natural teeth.

Fig 9 The translucency and light reflection of e.maxPress (Ivoclar Vivadent) emulates those of the naturaltooth.



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emergence profile, a soft tissue cast must be fabri-cated with the provisional in place.

Once the opaque gold-palladium posts areplaced, the profile of the planned abutments mustbe checked. This way, all the technician will haveto do is correct the emergence profile and moldeach of the abutments with wax using the siliconematrix as a guide (Fig 10b). The provisionalrestorations and ring attachments in the posterior

region will mark the path of insertion. The place-ment of these gold rings is necessary to obtain agood passive fit while acting as a connector be-tween the implant and the restoration. When theprofile is well defined, the wax pattern is preparedfor replacement with pressed ceramic (Fig 11), inthis case with medium opacity e.max Press MO1(Ivoclar Vivadent, Schaan, Lichtenstein) (Fig 12).Once injected with ceramic, the fit is verified, acid

Fig 10a Gold-palladium abutment.

Fig 10b Waxup of the abutments after obtaining a proper emergence profile.

Fig 11 The wax pattern is prepared for replacement with pressed ceramic.

Fig 12 Ceramic abutment cover after pressing with e.max Press MO1.

10a 10b

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etching is carried out, and the adhesive cement isapplied (Multilink, Ivoclar Vivadent) (Figs 13 to 15).After the abutments have been cemented and thepath of insertion is identified, the abutment sur-faces can be polished (Figs 16 and 17).

With the abutments finished, the gold rings areattached to the two posterior implants (Figs 18and 19). The coping is then molded in compositeresin and processed in zirconia (Figs 20 to 23). This

way, the zirconia coping will already have the cav-ity needed to house the gold rings. Once the ce-ramic has been pressed, the gold rings can be ce-mented, ensuring an acceptable passive fit.

The ceramic is applied to the zirconia in a con-ventional manner based on standard shades (A1 toA2) (Fig 24). At this point, it is up to the ceramist tochoose which stains will be applied to achieve avital color.

Fig 13 The abutment was etched with hydrofluoricacid and silanated. Note that the screw was pro-tected with blue wax.

Fig 14 In a second stage, the pressed ceramic abut-ment cover was also etched and silanated.

Fig 15 The pressed ceramic cover was cementedover the metal structure.

Fig 16 Final abutments after being finished and polished, respecting the path of insertion.

Fig 17 The cast is ready for the fabrication of zirconia copings, which will be cemented in the an-terior region and screw retained in the posterior region.

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24

Figs 18 and 19 In the posteriorregion, a gold ring is used as aconnector between the implantand the zirconia coping.

Fig 20 The copings weremolded in composite resin andthen processed in zirconia.

Fig 21 Framework after pro-cessing in zirconia.

Fig 22 Zirconia frameworktry-in.

Fig 23 Repositioning the goldring, which will then be ce-mented in the coping.

Fig 24 Ceramic is convention-ally applied using standardshades (A1 to A2).

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One of the problems with metallic structures isthe lack of control of passive fit after the ceramichas been processed. Zirconia is much more stablein this regard, even though the better choice is stillto use a cemented prosthesis if a good passive fitis desired. For this reason, once the glazed ce-

ramic is ready, it should be cemented to the goldrings that were previously screwed into the twoposterior implants (Fig 25). At this stage (Fig 26),the site is ready to be torqued down and therestoration can be cemented in the patientsmouth (Figs 27 to 30).

Fig 25 The glazed ceramic structure is cemented to the screw-retained at-tachments at the posterior implants.

Fig 26 Passive fit is achieved once the attachments have been cemented.

Figs 27 to 30 Final result.

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CONCLUSIONSImplementation of new materials such as zirconiaand pressed ceramic in implantology has made itmuch easier to obtain satisfactory results. The factthat these materials are both highly esthetic andfunctional is a great advancement. Until recently,only metallic structures were available whenstrength was of primary concern; however, thesepromising new materials offer excellent outcomesand great patient satisfaction.

ACKNOWLEDGMENTSThe authors thank all of the patients that have trusted in usand all of the professionals that, with much effort, have madethis paper possible.

REFERENCES1. Rutten L, Rutten P. CrownBridge and Implants. Fuchstal:

Teamwork Media, 2006.2. Schunke S. The functional-esthetic complex: Considera-

tions based on clinical cases. Quintessence Dent Technol2008;31:135152.

3. Riva D, Pizzoni L. Zirconia implant fixed partial denture re-placing multiple missing teeth in the esthetic zone: Acase report and technical aspects. Quintessence DentTechnol 2008;31:163170.

4. Mitrani R, Phillips K, Escudero F. A simplified approach inthe fabrication of an implant-supported, full-mouth, fixedmetal-ceramic restoration. Pract Proced Aesthet Dent2004;16:125127.

5. Mitrani R, Vasilic M, Bruguera A. Fabrication of an im-plant-supported reconstruction utilizing CAD/CAM tech-nology. Pract Proced Aesthet Dent 2005;17:7178.

6. Grel G, Bichacho N. Permanent diagnostic provisionalrestorations for predictable results when redesigning thesmile. Pract Proced Aesthet Dent 2006;18:281286.

7. Gamborena I, Blatz MB. Current clinical and technical pro-tocols for single-tooth immediate implant procedures.Quintessence Dent Technol 2008;31:4960.

8. Kina S, Bruguera A. Invisible, Restauraes Estticas emCermica. So Palo: Editora Artes Mdicas, 2007.

9. Bruguera A. Shades: A World of Color. Fuchstal: Team-work Media, 2003.

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New Materials Inimplantology