CAD/CAM-generated high-density polymer ...

Q U I N T E S S E N C E I N T E R N AT I O N A L

CAD/CAM-generated high-density polymer restorations for the pretreatment of complex cases: A case report Daniel Edelhoff, Prof Dr Med Dent, CDT1'MPSJBO#FVFS 1SJW%P[%S.FE%FOU2/ Josef Schweiger, CDT30MJWFS#SJY $%54/Michael Stimmelmayr, Dr Med Dent2/ Jan-Frederik Güth, Dr Med Dent2

Complex rehabilitations represent a particular challenge for the restorative team, especially if the vertical dimension of occlusion (VDO) needs to be reconstructed or redefined. The use of provisional acrylic or composite materials allows clinicians to evaluate the treatment objective over a certain period of time and therefore generates a high predictability of the definitive rehabilitation in terms of esthetics and function. CAD/CAM technology enables the use of prefabricated polymer materials, which are fabricated under industrial conditions to form a highly homogeneous structure compared with those of direct fabrication. This increases long-term stability, biocompatibility, and resistance to wear. Furthermore, they offer more suitable CAD/CAM processing characteristics and can be used in thinner thicknesses than ceramic restorative materials. Also, based on the improved long-term stability, the transfer into the definitive restoration can be divided into multiple treatment steps. This article presents different clinical cases with minimally invasive indications for CAD/CAM-fabricated temporary restorations for the pretreatment of complex cases. (Quintessence Int 2012;43:457–467)

Key words: CAD/CAM manufacturing, complex rehabilitations, esthetic evaluation, functional evaluation, high-density polymers, provisional restorations, vertical dimension of occlusion

CAD/CAM (computer-aided design/com-

objective. Therefore, it is an important com-

puter-assisted

ponent in a complex treatment strategy.

manufacturer)-fabricated

high-density polymer restorations have the

The use of provisional restorations rep-

potential to offer a noninvasive temporary

resents an essential stage in the course

diagnostic tool to reconstruct an adequate

of indirect restorative and interdisciplinary

vertical dimension of occlusion (VDO) in

treatment strategies. They are normally used

situations of severe tooth wear. An expe-

to protect the prepared tooth structure and

ditious approach offers the possibility to

pulp and stabilize the teeth. In addition, they

restore patients in a relatively short period

play an indispensable role in preserving or

of time with adhesively luted provisional

reestablishing masticatory function, phonet-

restorations, which represent the treatment

ics, and esthetic appearance. According to the fabrication technique, provisional resto-

1

Tenured Associate Professor, Department of Prosthodontics, Dental School of the Ludwig-Maximilians-University Munich,

2

3

Associate Professor, Department of Prosthodontics, Dental

nique), and indirect restorations. The recom-

School of the Ludwig-Maximilians-University Munich, Munich,

mended wear time of individual provisional

Germany.

restorations varies and depends on the dif-

Head of Laboratory, Department of Prosthodontics, Dental

ferences in material properties achieved by

School of the Ludwig-Maximilians-University Munich, Munich,

the various fabrication techniques. Generally,

Germany. 4

rations are divided into direct, indirect-direct (known as the eggshell or veneering tech-

Munich, Germany.

a wear time between 1 and 3 months is

CDT, Innovative Dental-Design, Wiesbaden, Germany.

Correspondence:

Prof

Dr

Med

Dent

Daniel

Edelhoff,

Department of Prosthodontics, Dental School of the LudwigMaximilians-University, Goethestrasse 70, 80336 Munich, Germany. Email: [email protected]

VOLUME 43 t /6.#&36 t +6/& 2012

recommended for provisional restorations fabricated with the direct technique, up to 6 months for the veneering technique, and up to 2 years for the indirect technique.

457

Q U I N T E S S E N C E I N T E R N AT I O N A L E d e l h o ff e t a l

Table 1

Overview of high-density polymers for CAD/CAM manufacturing

Trade Name

Manufacturer

Indication

Ambarino High-class

Creamed Creative Medizintechnik

Definitive single-tooth restorations and FDPs, telescopic protheses, tertiary structures, fully/partially anatomically milled restorations, milled emergence profiles, implant superstructures and abutments

BSU#MPD5FNQ

Merz Dental

Long-term provisionalization of crowns, partial crowns, and FDPs, immediate implant restorations

Artegral imCrown

Merz Dental

Long-term provisionalization of single crowns in the anterior region

CAD-Temp

Vita Zahnfabrik

Single- and multiunit, fully and partially long-term provisional restorations with up to 2 pontics

cara PMMA prov

Heraeus Kulzer

Tooth-colored PMMA for the CAD/CAM manufacturing of provisional crowns and fixed partial dentures

Cercon base PMMA

Degudent

Provisional crowns and multiunit FDP with up to 16 units (with one pontic between the abutment teeth) for a period of clinical service of up to 6 mo

Everest C-Temp

KaVo

Frameworks for provisional FDPs with veneering and with a span up to 60 mm

/FX0VUMJOF$"5

Anax Dent

Provisional single and FDP frameworks up to 2 pontics, for a period of clinical service of 3 to 12 months, relinable

Organic Composit

3 ,$"%$". Technologie

Approved for definitive restorations of up to 3 units

Paradigm MZ 100 (available only in the USA)

3M ESPE

Final inlays, onlays, veneers, and single crowns

Polycon ae

Straumann CAD/CAM

Long-term provisional restorations, crowns, and FDPs with 1 pontic in the anterior and posterior region

Telio CAD

Ivoclar Vivadent

Long-term provisional restorations, from single-tooth restorations up to 4-unit FDPs including restorations on implants

Zenotec Pro Fix

8JFMBOE%FOUBM

Long-term provisional restorations, fully anatomical crowns and FDPs up to two pontics in the anterior and posterior region

FDP, fixed dental prosthesis; CAD/CAM, computer-aided design/computer-assisted manufacture; bis-GMA, bisphenol glycidyl methacrylate; 1.." QPMZNFUIZMNFUIBDSZMBUF0.1 PSHBOJDNPEJGJFEQPMZNFS*1/ JOUFSQFOFUSBUFEOFUXPSLQPMZNFS.31 NJDSPGJMMFSSFJOGPSDFEQPMZBDSZMJD TEGDMA, triethylene glycol dimethacrylate.

Various polymer systems are suitable

Hence, for a prolonged period of clinical

for the fabrication of direct provisional res-

application, indirect provisional restorations

torations: Powder-liquid systems based on

are usually fabricated in the dental labora-

monomethacrylate (MMA) and polymethyl

tory. In particular, when used as long-term

methacrylate (PMMA), paste-paste systems

fixed dental prostheses (FDPs), they need a

based

metal alloy or glass fiber–reinforced frame-

on

difunctional

or

multifunctional

methacrylate (eg, bis-GMA [bisphenol glycidyl methacrylate], TEGDMA [triethylene gly-

work to increase their load capability. Currently,

many

manufacturers

offer

col dimethacrylate], and UDMA [urethane

high-density polymers based on highly

dimethacrylate]), and preformed light-curing

cross-linked PMMA acrylic resins or com-

composite restorations (eg, Protemp Crown,

posites for CAD/CAM manufacturing meth-

3M ESPE). Due to unfavorable conditions

ods (Table 1). Since they are manufactured

under which they are polymerized and fab-

in an industrial process, provisional res-

ricated, direct provisional restorations are

torations made of high-density polymer

prone to inhomogeneities, pores, and cracks,

exhibit qualities superior to those of direct

which may lead to premature discoloration,

restorations.3–5

bacterial ingress, and a significant decrease

treatment options such as an extended pre-

in long-term stability and biocompatibility.1,2

liminary treatment phase.

458

This offers numerous new

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Description

CAD/CAM system

Highly crosslinked polymer blends (bis-GMA, urethane methacrylate, butanediol dimethacrylate, 70.1 wt%, ceramic-type anorganic silicate glass fillers)

Micron 400 (Micron), M7 Dental (Datron), All systems with circular blank automation holder and corresponding templates

Ingot made of highly crosslinked, interpenetrated PMMA (or OMP networks)

Cerec (Sirona)

Semifinished blanks made of unfilled PMMA material with highly crosslinked NBDSPNPMFDVMBSTUSVDUVSF PS*1/T

Cerec (Sirona)

High-molecular, cross-linked acrylic polymer containing 14 wt%, microfillers PS.31

Cerec (Sirona), Everest (KaVo)

PMMA and crosslinked copolymers of the methacrylic acid

cara (Heraeus)

PMMA and crosslinked copolymers of the methacrylic acid

Cercon System (Degudent)

Glass fiber–reinforced high-density polymer as framework material

Everest (KaVo)

PMMA and copolymers of methacrylate, n-alkyl methacrylate, and pigments

0SHBOJDBM 3àCFMJOH,MBS

0QFO;FOP 8JFMBOE

1,4 butanediol dimethacrylate urethane dimethacrylate bis-GMA

0SHBOJDBM 3àCFMJOH,MBS

Polymer consisting of bis-GMA and TEGDMA matrix with 85 wt% zirconium oxide microfillers

Cerec 3 (Sirona), E4D (DVD)

1.."CBTFEBDSZMBUFSFTJOXJUI*1/

Straumann CAD/CAM

99.5% PMMA polymer

1SPDFSB /PCFM#JPDBSF

$FSFD 4JSPOB

Fiber-free, homogenous, methacrylate-based acrylomer

"MM;FOPUFD 8JFMBOE

Using these modifiable provisional res-

smile line. Further on, the provisional resto-

torations over an extended period of time,

ration plays an essential role in the commu-

the patient and restorative team can clini-

nication among the patient, clinician, and

cally evaluate the restorative blueprint with

dental technician during treatment. 6

regard to its esthetics, masticatory function, and phonetics.6 In situations in which a new VDO has to be defined using occlusal splints, it is a challenge to transfer the new VDO into a longterm provisionalization using a minimally

MINIMALLY INVASIVE AND NONINVASIVE OCCLUSAL ONLAYS

invasive or noninvasive method. Moreover, prolonged preliminary treatment phases are indispensable if extensive modifications of

In the future, the number of patients with

shape, shade, and position in the esthetic

severe loss of tooth structure will increase.

anterior region are implemented, because

One reason for this increase is a demo-

essential factors such as lip position and

graphic change, with older people making

dynamics cannot be sufficiently assessed

up an increasing proportion of the popula-

in the dental laboratory to determine the

tion. Due to heightened health awareness

VOLUME 43 t /6.#&36 t +6/& 2012

459


Fig 1 Case 1. Preoperative view. The esthetic appearance of the maxillary anterior region has been severely compromised by generalized defects caused by abrasive and erosive processes and traumatic injuries.

and improved dental care, people will main-

thin as 0.3 mm, their material properties

tain a healthy natural dentition for longer.7

seem to be favorable for these minimally

This means that natural teeth are exposed

invasive or noninvasive restorations such

to masticatory stresses for longer periods

as provisional veneers and onlays. These

of time, which leads to an increase in the

restorations can be manufactured consider-

functional wear of the natural dentition.8 The

ably thinner than the natural enamel layer,

physiologic wear occurring from frictional

which usually exhibits a thickness of more

contact between opposing teeth is called

than 1 mm. They can be placed using an

attrition. This continuous loss of tooth struc-

adhesive luting technique. Consequently,

ture may be accelerated by extrinsic factors

these measures help to save substantial

such as parafunctional stresses (malocclu-

amounts of tooth structure.

sion or bruxism) and chemical processes (acids).9 Such aggravating processes may prematurely lead to substantial esthetic and

CASE PRESENTATIONS

functional problems. Exogenic factors such as an increased consumption

of

acidic

beverages

and

Case 1

foods and endogenic factors such as buli-

A 29-year-old man requested treatment of

mia and gastroesophageal reflux represent

his extensive tooth defects. He reported

key factors causing erosion-induced loss of

increasing sensitivity to chemical and ther-

tooth structure in young patients. Increasing

mal stimuli and complained about the con-

numbers of young people, including chil-

siderable esthetic impairment created by

dren, are affected by this problem.10 In

the appearance of his teeth (Fig 1). After a

these cases, the attrition proceeds to the

review of the patient’s medical history and an

underlying dentin, and the wear processes

evaluation of the clinical findings, abrasive

might dramatically accelerate, which can

and erosive processes were identified as the

cause a substantial loss of the VDO. In

causative factors for the generalized loss of

the longer term, these changes will have

tooth structure. These processes were asso-

adverse effects on phonetics, masticatory

ciated with the patient’s grinding of teeth

function, esthetic appearance, and the neu-

during extreme sports activities and frequent

romuscular system of the patient.11 After the

consumption of acidic beverages. In addi-

causative factors of the wear have been

tion, sports-related traumatic incidents con-

redressed, restorative treatments should

tributed to the extensive defects. As a result

be initiated as soon as possible. Timely

of dental injuries, the proportions of the teeth

intervention is also advisable to ensure

had been severely affected (Figs 2 and 3).

that appropriate portions of enamel remain

The particular challenges of this com-

available for reliable adhesive cementation.

plex rehabilitation were reconstructing the

The reconstruction of the VDO often creates

VDO,

sufficient space to place thin-walled resto-

and esthetics, and satisfying the patient’s

rations. Since high-density polymer restora-

request for an immediate improvement of

tions can be fabricated in thicknesses as

the clinical situation.

460

establishing

appropriate

function

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Fig 2 Case 1. Preoperative view. The existing defects have also caused functional impairment due to the loss of anterior canine guidance.

Fig 3

Case 1. Initial findings. Severe loss of tooth structure, with functional and esthetic impairments.

Treatment planning. First, the lost tooth

1. Fabrication of an analytic wax-up for

structure should be replaced by high-den-

the reconstruction of a functionally and

sity polymer restorations in an additive

esthetically adequate tooth morphology

approach. The objective of this step was

and predefinition of the reconstructed

to achieve an immediate amelioration of

VDO.

the patient’s situation while sacrificing as

2. Intraoral esthetic evaluation of the wax-

little tooth structure as possible. For further

up with the help of a diagnostic template,

treatment planning, alginate impressions,

which was filled with a bis-GMA–based

a registration in centric relation, and an

direct provisional material and seated

arbitrary facebow registration were con-

on the isolated preexisting tooth struc-

ducted. Additionally, portrait photographs were taken to provide the dental technician information about the initial situation. 8JUI UIF QBUJFOUT JOQVU UIF SFTUPSBUJWF team decided to restore the severely dam-

ture (mock-up/esthetic try-in). 3. 3FQMBDFNFOUPGUIFJOTVGGJDJFOUGJMMJOHTGPMlowed by immediate dentin sealing (IDS) and slight beveling of the enamel areas in the maxillary anterior teeth (Fig 4).

aged dentition with noninvasive provisional

4. Transfer of the defined VDO into an

veneers and onlays made from high-den-

occlusal splint for a 12-week functional

sity PMMA and to bond these restorations

evaluation phase.

adhesively to the damaged tooth structure.

5. Precision impressions of both arches

To establish the reconstructed VDO, the

and bite registration according to the

treatment team decided on the following

successfully clinically proved occlusal

course of eight treatment steps:

splint position. For the transfer of the

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461


Fig 4 Case 1. Adhesive sealing. Adhesive sealing of the exposed dentin areas in the pulp region of the maxillary anterior region using a multistep adhesive and low- and high-viscosity composite.

Fig 5 Case 1. Transfer of VDO by separated splint. The occlusal splint was separated in half to transfer the reconstructed VDO. A corresponding bite registration was conducted related to each part of the splint, which was joined together again at the end of the session. Fig 6 Case 1. Provisional restorations after the milling process. Unfilled PMMA-based high-density polymer block (Telio CAD) with occlusal onlays immediately after the CAD/CAM milling process in an inLab MC XL milling unit.

reconstructed VDO, the occlusal splint

provisionals were designed identically

was halved, and a corresponding bite

to the shape of the digitized analytic wax-

registration was conducted related to

up. The provisional restorations were

each part of the splint. The splint would

CAD/CAM fabricated from PMMA-based

be joined together at the end of this ses-

high-density polymer blocks (Telio CAD,

sion (Fig 5).

Ivoclar Vivadent) (see Table 1) utilizing a

6. Digitization of the wax-up, design, and CAD/CAM fabrication. The veneer-shaped

462

three-axis milling unit (Cerec inLab MC XL system, Sirona) (Fig 6).

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Fig 7 Case 1. Conditioning of teeth. Conditioning of composite areas on the abutment teeth with an intraoral silicoating device (CoJet, 3M ESPE). A transparent template was placed over the neighboring structures to protect them during air abrasion, while the surfaces in need of conditioning remained uncovered.

Fig 8 Case 1. Maxilla before and after treatment. Pre- and postoperative occlusal view of the maxilla. The provisional high-density polymer restorations were placed with the adhesive technique.

7. Adhesive

placement.

For

the

inser-

nique (Fig 7). Figure 8 displays the intra-

light-curing

oral situation before and after placement.

resin cement (Variolink Veneer, Ivoclar

8. Clinical evaluation of the provisional res-

Vivadent) in the same shade of the try-

torations (at least for 12 months) with the

in paste was used. The inner surfaces

option of modification.

tion

of

the

provisionals,

of the restorations and the composite buildups on the maxillary anterior teeth

#Z HFOFSBUJOH BO FYUFOEFE QSPWJTJPOBM

XFSF TJMJDPBUFE 3PDBUFD 4PGU N

treatment phase with additive restorations, it

3M ESPE) (nozzle-to-surface distance,

was possible to evaluate the reconstruction

10 mm; pressure, 1 bar [14.5 psi]; air

of the VDO for at least 12 months without bio-

abrasion time per unit, 5 seconds), and

logic costs. This offers a high predictability of

a silane agent was applied. The tooth

the outcome of the extensive definitive resto-

structure was conditioned with a multi-

ration. The esthetic and functional require-

step dentin adhesive (Syntac Classic,

ments of the patient could be accomplished

Ivoclar Vivadent) using a total-etch tech-

in a brief treatment period of only 4 months

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463


Fig 9 Case 1. Placed provisional restorations. Palatal view after adhesive cementation of the provisional occlusal veneers and onlays. By increasing the VDO, the traumatic anterior contacts were eliminated, and the teeth were restored to their correct proportions.

Fig 10 Case 1. Placed provisional restorations. The anterior restorations exhibit a minimum thickness of only 0.3 mm and are not veneered. Nonetheless, they blend in with the surrounding dentition, ensuring a pleasing esthetic appearance.

Fig 11 Case 1. Clinical result. Reconstruction of the VDO by provisional restorations including dynamic occlusion with anterior and canine guidance.

using a virtually noninvasive approach. The

rations can be carried out, also segment by

outcome met with the complete satisfaction

segment. If necessary, the adhesively luted

of the patient (Figs 9 to 11).

temporary material may be used as build-

Further treatment and transfer of the pro-

ups in the subsequent preparation for the

visionals to lithium-disilicate-ceramic resto-

definitive restorations.

464

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Fig 12 Case 2. Initial situation. Missing mandibular first molar. The generalized destruction of the tooth structure has resulted in a loss of vertical dimension and functional impairment.

Fig 13 Case 2. Individual abutment. Situation after implantation and insertion of a CAD/CAM-manufactured zirconium dioxide ceramic abutment with a titanium component.

Case 2 #JPUFDIOPMPHJFT EJBNFUFS NN MFOHUI A 28-year-old man was referred with the

11 mm) was inserted in the region of the

request to have his severe tooth defects

missing mandibular right first molar with the

and edentulous gap in the region of the

help of an implant template created from

mandibular right first molar restored with

the analytic wax-up. After a 3-month heal-

tooth-colored restorations. Initial findings

ing phase, impressions of both arches were

revealed generalized defects caused by

taken using a polyether impression material

abrasive and erosive processes (Fig 12),

(Impregum/Permadyne blue, 3M ESPE).

which necessitated a reconstruction of the

Fabrication and insertion of provisional restorations. The implant was supplied

VDO. Treatment planning. After identification

with a zirconium dioxide ceramic abutment

and elimination of the reason for the erosive

(inCoris ZI meso, Sirona) using the Sirona

destruction and the evaluation of alternative

CAD/CAM system (inLab MC XL) with an

treatment options, the patient and restor-

adhesive titanium base (Camlog) (Fig 13).

ative treatment team agreed on replace-

The provisional implant crown and occlusal

ment of the missing mandibular right first

veneers and onlays were fabricated on

molar with a single-tooth implant and a

the basis of the analytic wax-up and CAD/

CAD/CAM-manufactured zirconium diox-

CAM manufactured (inLab MC XL) (Fig 14)

ide abutment. After the preliminary treat-

from a high-density PMMA material with

ment was complete, initial comprehensive

a low amount of fillers (CAD-Temp, Vita)

rehabilitation using provisional high-density

(see Table 1) in an entirely additive design.

polymer restorations would be carried out.

The single implant-supported crown was

prelimi-

cemented with temporary material (Kerr

analo-

Life, Kerr), whereas partial restorations were

gously to case 1. During this stage, an

permanently seated as described in case 1,

implant (ScrewLine Promote Plus, Camlog

using the adhesive technique (Fig 15).

Preliminary nary

treatment

treatment. was

The

conducted

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465


Fig 14 Case 2. Restoration after CAD/CAM. Provisional occlusal onlays and one single crown made of low-filler PMMA-based high-density polymer immediately after the CAD/CAM milling process.

Fig 15 Case 2. Provisional restorations after placement. Situation after the provisional insertion of the implant crown and adhesive cementation of the occlusal onlays. A functionally and esthetically pleasing reconstruction of the tooth structure was achieved with minimal biologic costs.

DISCUSSION

standardized conditions used in industrial fabrication processes allow the elimination of these shortcomings by using high-pres-

The specialized literature discusses various

sure polymerization. Over the years, the

strategies for the treatment of generalized

authors have gathered favorable experienc-

tooth defects caused by a combination of

es with CAD/CAM-fabricated, high-density

abrasive and erosive processes. These

PMMA or composite-based polymers for

approaches are based mainly on direct

the above described treatment strategy.13

composite resins, which are fabricated using

In in vitro studies, CAD/CAM-fabricated

a purely additive design and often allow a

ultrathin composite onlays demonstrated an

completely noninvasive treatment method.4

increased survival rate and higher fatigue

Although this conservative approach offers

resistance when compared with those made

some advantages, it involves direct treat-

of ceramic.14,15 Only insufficient clinical data

ment procedures that are time consum-

are available to prove the long-term reli-

ing for the patient and clinician alike. The

ability of this new type of restoration. In a

approach presented promotes an indirect

clinical study with traditionally fabricated

treatment strategy based on a close col-

composite full crowns, the authors saw

laboration with the dental technician. Since

some restrictions for the use as a definitive

essential steps are delegated to the dental

restoration due to a complication rate of

laboratory, the chair time for the patient can

more than 10% and increased plaque accu-

be significantly reduced. In addition, the

mulation.16 After 5 years of clinical service,

use of industrially prefabricated compo-

a probability of 88.5% survival was report-

nents in a CAD/CAM-based indirect manu-

ed. In a clinical trial comparing CAD/CAM-

facturing technique results in restorations

manufactured composite resin crowns with

that exhibit superior material qualities.12 The

CAD/CAM-manufactured

466

ceramic

single

VOLUME 43 t /6.#&36 t +6/& 2012


crowns after 3 years, significantly higher

3. Ireland MF, Dixon DI, Breeding LC, Ramp MH. In

cumulative survival and success rates were

vitro mechanical property comparison of four resins

found for the group of the ceramic restora-

used for fabrication of provisional fixed restorations.

17

tions.

Esthetics and wear resistance of the

composite resin crowns were inferior compared with those manufactured of ceramic. However, in a 3-year clinical trial of CAD/

J Prosthet Dent 1998;80:158–162. 4. Koksal T, Dikbas I, Kazaoglu E. Alternative restorative approach for treatment of patient with extremely worn dentition. N Y State Dent J 2009;75:52–55. 5. Schmidlin PR, Filli T, Imfeld C, Tepper S, Attin

CAM-generated adhesive inlays fabricated

T. Three-year evaluation of posterior vertical bite

either from composite or ceramic, no signifi-

reconstruction using direct resin composite—

cant differences relative to margin adaptation could be found between groups.18 For

PMMA-based

high-density

poly-

mer materials used for provisional ultrathin onlays and veneers, no scientific clinical data are available yet. Until the first positive results of clinical midterm trials, this new restorative approach has to be considered experimental.

A case series. Oper Dent 2009;34:102–108. 6. Magne P, Cascione D, Donovan TE. Immediate dentin sealing improves bond strength of indirect restorations. Prosthet Dent 2005;94:511–519. 7. Bartlett DW, Blunt L, Smith BGN. Measurement of tooth wear in patients with palatinal erosions. Br Dent J 1997;182:179–184. 8. Passos SP, Ozcan M, Vanderlei AD, Leite FP, Kimpara ET, Bottino MA. Bond strength durability of direct and indirect composite systems following surface conditioning for repair. J Adhes Dent 2007;9:443–447. 9. Hattab FN, Othman MY. Etiology and diagnosis of tooth wear: A literature review and presentation of

SUMMARY

selected cases. Int J Prosthodont 2000;13:101–107. 10. Rieder CE. The use of provisional restorations to develop and achieve esthetic expectations. Int J

8JUI

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PG

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manufactured, high-density polymer materials, high-quality provisional restorations became available. These provisionals help

Periodontontics Restorative Dent 1989;9:122–139. 11. Litonjua LA, Andreana S, Bush PJ, et al. Tooth wear: Attrition, erosion, and abrasion. Quintessence Int 2003; 34:435–446. 12. Schmidlin PR, Filli T, Imfeld C, Tepper S, Attin

gather valuable information for the fabri-

T. Three-year evaluation of posterior vertical bite

cation of the definitive restorations. They

reconstruction using direct resin composite—

therefore represent a key component in a

A case series. Oper Dent 2009;34:102–108.

complex treatment strategy. The possibility

13. Stumbaum M, Konec D, Schweiger J, Gernet W.

of modifying and fine-tuning the restorations

Reconstruction of the vertical jaw relation using

helps the dental team achieve an optimal definitive restoration with active involvement of the patient. Occlusal conditions and material thickness may be used as essential criteria for selecting the materials

CAD/CAM. Int J Comput Dent 2010;13:9–25. 14. Magne P, Schlichting LH, Maia HP, Baratieri LN. In vitro fatigue resistance of CAD/CAM composite resin and ceramic posterior occlusal veneers. J Prosthet Dent 2010;104:149–157. 15. Schlichting LH, Maia HP, Baratieri LN, Magne P.

for the definitive restoration. Combined with

Novel-design ultra-thin CAD/CAM composite resin

the possibility of implementing the definitive

and ceramic occlusal veneers for the treatment of

restoration in different stages, this treatment

severe dental erosion. J Prosthet Dent 2011;105:

alternative improves the predictability and reliability of complex rehabilitations.

217–226. 16. Lehmann F, Spiegl K, Eickemeyer G, Rammelsberg P. Adhesively luted, metal-free composite crowns after five years. J Adhes Dent 2009;11:493–498. 17. Vanoorbeek S, Vandamme K, Lijnen I, Naert I.

REFERENCES

Computer-aided designed/computer-assisted manufactured composite resin versus ceramic singletooth restorations: A 3-year clinical study. Int J Prosthodont 2010;23:223–230.

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18. Fasbinder DJ, Dennison JB, Heys DR, Lampe K. The clinical performance of CAD/CAM-generated composite inlays. J Am Dent Assoc 2005;136:1714–1723.

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