retentive systems for implant-borne hybrid dentures
TRANSCRIPT
P R O S T H E T I C S
Retentive systems for implant-borne hybrid dentures
DEN
TAL
IMPL
AN
T SY
STEM
Disclaimer of liabilityThe ITI dental implant is part of an overall concept andmay only be used in conjunction with the associatedoriginal components and instruments according to InstitutStraumann AG’s instructions and recommendations.
Use of products made by third parties in conjunction withthe ITI® DENTAL IMPLANT SYSTEM will void any warrantyor other obligation, express or implied, of Straumann.
Instructions as to application of our products take placeverbally, in writing, by electronic media or in hands-ontrainings corresponding to state of the art at the time ofintroduction of the product.The user of ITI products has the duty to determine whetheror not any product is suitable for the particular patientand circumstances. Straumann disclaims any liability,express or implied, and shall have no responsibility forany direct, indirect, punitive or other damages, arisingout of or in connection with any errors in professionaljudgment or practice in the use or installation of ITIproducts. As a general rule, our products must be securedagainst aspiration when used intra-orally.
The user is also obliged to study the latest developments ofthe ITI® DENTAL IMPLANT SYSTEM and their applicationsregularly.
Please noteThe descriptions given are insufficient to allow immediateuse of the ITI® DENTAL IMPLANT SYSTEM. Guidance inthe handling of these instruments by a doctor experiencedin their use is strongly recommended.
ValidityUpon publication of this brochure, all previous versionsare superseded.
AvailabilityNot all products listed in this brochure are available inall countries.
DeliveryFederal law restricts these devices to sale by or on theorder of a dentist or a physician.
Units per packageUnless stated otherwise, there is one unit in each package.
DocumentationYou can obtain detailed instructions on the ITI® DENTALIMPLANT SYSTEM from your Straumann representative.
Copyright and trademarksStraumann documents may not be reprinted or published,in whole or part, without the written authorization ofInstitut Straumann AG. ITI® DENTAL IMPLANT SYSTEM,synOcta®, Octasystem® and ITI TE® are registeredtrademarks of Institut Straumann AG, Switzerland.
Description of the symbols on labels and instructionsfor use
Lot/batch number
Article number
Sterile by gamma irradiation
Nonsterile
Do not use on patients
Do not reuse
Refer to instructions for use
Use before expiry date
Colored warning labels
YELLOW ➡ CAUTION: In case of danger or unsafe handling, which might cause slight bodily injury or damage to property.
ORANGE ➡ WARNING: In case of danger which might cause severe bodily injury or death.
RED ➡ DANGER: In case of danger which may cause severe bodily injury or death, immediately.
Definition SLA: Sand-blasted, Large grit,Acid-etched
LOT
REF
RSTER I L E
IMPORTANT NOTES
STER I L E
Con
tent
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1
Instructions for dentists and dental technicians
Table of contents
■ Planning principles and recall appointments 2
Bar-borne restorations 3
■ Introduction 3
■ Fabrication of an implant-borne bar in the lower jaw using the 6synOcta® prosthetics system
■ Fabrication of cast and laser-welded bars 18
■ Fabrication of the final bar restoration with metal reinforcement 22
■ Modification of an existing full lower denture in an implant/ 24bar-borne hybrid denture
■ Relining of an implant-borne bar denture 26
Retentive anchors 29
■ Introduction 30
■ Fabrication of a new full lower denture with metal reinforcement 31and two gold matrices
■ Fabrication of a new full lower denture with metal reinforcement 36and two titanium matrices
■ Modification of an existing full lower denture in an 42implant-borne retentive anchor denture
■ Relining of an implant-borne retentive anchor denture 44
Magnets 49
■ Introduction 50
■ Fabrication of a full lower denture with two magnets 53
■ Modification of an existing full lower denture on an 58implant-borne magnet denture
■ Relining of an implant-borne magnetic denture 60
Plan
ning
2
Planning principlesImplant-borne full dentures requirethorough planning of the surgicaland technical procedures. Thenumber and positions of theimplants as well as the design ofthe denture and occlusion shouldtake account of the anatomical,functional and hygienic aspects.The static/dynamic conditionsgovern the selection of theretentive units (Besimo, 1993).
Magnet and bar retention systemsfor implant-borne lower hybriddentures subject the implantabutments to the lowest stress(Jäger and Wirz, 1993).
Recall appointmentsHybrid dentures with resilientretention units must be examinedat intervals of approximately 3 months to ensure harmfulexcursions of the denture areeliminated in their early stages(possible methods: relining,activating/replacing the matrix,checking the occlusion).
In cases of poor oral hygiene, thepatient should undergo thoroughscaling and polishing, as well asre-instruction and motivation tomaintain the necessary high levelof oral hygiene. If the patient is co-operative, the interval betweencheck-ups can be increased.
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IntroductionThe functions of a bar restoration:
■ Stabilisation and primarysplinting of implants
■ Countering the forces that woulddislodge the denture
■ Distribution of shear forces
■ Resilience compensation throughdegrees of freedom
Description/FunctioningMost common types of bar:
Dolder® bar (egg-shaped cross-section), normal and mini versions:The Dolder® bar is a retention unitallowing three degrees of freedom(translateral and rotary move-ments).
Dolder® bar attachment, “U”-shaped cross-section:The bar attachment is a rigidretentive unit with no rotationalfreedom.
Round bar:The round bar is a retention unitpermitting only one degree offreedom (translateral movements).
Bar-borne restorations
1 Dolder®
registered trademark from Prof. Eugen Dolder, former director,School of Dentistry, University of Zurich
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The following guidelines mustabsolutely be heeded whenfabricating implant-borne hybriddentures:
Freedom:“If riders are placed on more thanone bar segments, the denture isretained, but has no degree ofspace freedom regardless of thecross-section of the bar.” (Wirz, 1994)
”If a rider is placed on theanterior-most bar segment only, a round bar creates 1 degree ofspace freedom, an egg-shapedcross-section 3 degrees of freedomand a bar attachment (or milledbar) no freedom.” (Wirz, 1994)
Bar positioning:The anterior bar is positionedperpendicular to the median lineof the two halves of the alveolarridge. (Wirz, 1994)
The bar must be horizontal – evenif the ridge varies in height. Thebar must never be allowed toslope as this would impede thecorrect functioning of the barattachment and create undesirablehorizontal forces. (Wirz, 1994)
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Planning the barrestorationEarly loading of the implant orfabrication of the restoration oncethe healing period has elapsed
“If full lower dentures are to beretained on ITI Dental implants, thefollowing basic principle applies:Four implants are required if afterimplantation, for any reasonwhatsoever, the implant abutmentshave to be loaded with a denturebefore osseointegration has beencompleted. This is often necessarywhen one-part implants are used,as the conditions of the temporaryrestoration are usually veryunfavourable. In such cases, it isimperative that the four implantsare splinted with a bar.
When used in the linear and frontareas only, the Dolder bar joint,with its three different degrees of space freedom, loads the abut-ments least of all regardless of the number of abutments. If,however, the abutments arespaced regularly in the anteriorregion, and the denture is retainedon all bar segments using severalriders – regardless of the cross-section of the bar – the dynamics of the denture are lost completely.This is a purely rigid type ofretention with no freedom whatso-ever. If we are able to allow atleast three months for osseointe-gration of two-part implants –which should usually be the case –we may limit ourselves to tworelatively short implant abutments,assuming that the masticatoryforces are absorbed by thedenture bed and not by theimplant site.” (Wirz, 1994).
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Fabrication of an implant-borne bar in the lower jawusing the synOcta® prosthetics system“Patient” – initialsituation: Edentulous lower jaw, with 4 two-part ITI Dental implants in positions44–34.
Important: The synOcta® abut-ments can be used only with theimplants with art. Nos. 043.xxxS.
Impression-taking withsynOcta® prosthetics:Two versions are available for the impression procedure: the“snap-on” version and the “screw-retained” version. The snap-onversion can be regarded as thestandard and can be used in the majority of cases. The screw-retained version is particularlyindicated where the implantshoulder lies very deep.
In order to prevent any risk ofconfusion, the transfer system iscolour-coded. The positioningcylinder, analog and screw-retained impression cap arecolour-coded red in the synOcta®
prosthetic system.
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A. “Snap-on” impres-sion procedure All parts of the transfer system aresupplied non-sterile. They can bedisinfected, as required, usingstandard commercial disinfectantsfor plastic products. (Please followmanufacturers’ directions).
Caution: The plastic parts aredesigned for single use only. They must not be sterilised in theautoclave.
To prevent damage to the plasticcomponents (loss of elasticity,embrittlement), they must beprotected from heat and light.
The implant shoulder and interiormust be thoroughly cleaned priorto the impression procedure. Theimpression cap (048.017) ispushed onto the implant until theshoulder clicks into place. Theimpression cap is turned gently inorder to check that it is in thecorrect position. When the cap isin the correct position, it can berotated on the implant.
Important: To avoid errors duringthe impression procedure, it mustbe ensured that the shoulder andthe margin of the impression capare not damaged.
Important: Due to its insufficienttensile strength and inadequateelastic recoil, hydrocolloid is notsuitable for this application.
The octagon on the positioningcylinder must be aligned with theinternal octagon on the implantand be inserted into the impres-sion cap until it is flush with thetop of the impression cap.
The impression should be takenusing an elastomeric impressionmaterial (polyvinylsiloxane orpolyether rubber).
“click”
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B. “Screw-retained”impression procedure A special tray with perforations isrequired for this application.
The implant shoulder and interiormust be thoroughly cleaned priorto the impression procedure. The impression cap (048.010) isplaced on the implant and istightened with the integral posi-tioning screw. Precise positioningof the octagon of the impressioncap into the octagon of theimplant is important. Should onlya limited amount of space beavailable, the occlusal aspect ofthe cap can be reduced by oneretention ring (once the positioningscrew has been removed).
Important: Only the integratedscrew must be used! The marginand octagon must not be damagedin order to prevent any errorsduring the transfer process. Forthis reason, the impression capsare for single use only. The impression should be taken
using an elastomeric impressionmaterial (polyvinylsiloxame orpolyether rubber) in accordancewith the manufacturer’s directions.
Once the material has set, thepositioning screws are loosened,and the impression is removed.
Important: Due to its insufficienttensile strength and inadequateelastic recoil, hydrocolloid is notsuitable for this application.
After impression-taking, thehealing caps are repositioned onthe implants.
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Fabricating the master castThe “snap-on” version:The red positioning cylinder showsthe dental technician that it is thered analog that must be used. Inthe laboratory, the analog(048.124) is repositioned in theimpression, and the shoulder mustclick audibly into place. The analog must not be rotated inthe impression.
The “screw-retained” version:The analog is secured in theimpression using the integralpositioning screw. The redimpression cap shows the dentaltechnician that it is the red analogthat must be used.
Important: When tightening thescrew, grasp the retentive sectionof the analog in order to preventthe impression cap from rotating.This is especially important if thecap has been shortened.
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Fabricating the working mastercast in the conventional way usingType 4 plaster (DIN 13911).
The synOcta® abutment (048.600)is placed in the analog andaligned in the octagon.
N.B.: The abutment must bepositioned in the octagon beforethe screw is tightened.
The screw is hand-tightened usingthe SCS screwdriver.
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Fabrication of the joint gold barThe prefabricated gold coping bar for the synOcta® prostheticssystem without an internal octagon(048.636) consists of a non-oxidising, high-melting alloy (HSL; Au 60%, Pt 19%, Pd 20%, Ir 1%; melting range 1400–1490°C). It is screwed onto theanalog/synOcta® abutment withthe 4.4 mm SCS occlusal screw(048.350V4). The gold copingis 5.6 mm high and cannot beshortened.
The individual bar segments areplaced between the abutmentunits. Attention should be paid tothe space between the bar andgingiva (min. 2 mm) to facilitateadequate cleaning and so preventchanges in the mucosa.
Important: To achieve a goodjoint, the gap should be as smallas possible.
Type of joinThe prepared bar can now besoldered or laser-welded, asdesired. A laser-assembled bardoes not require soldering withnon-precious ingredients and istherefore more biocompatible.Laser-welding takes place directlyon the plaster model and thereforetakes less work. Larger gaps arefilled with wire made from thesame type of material (see alsopage 20, Fabrication of laser-welded bars with titaniumcomponents).
Soldered gold bar:The gold copings and prefabricat-ed bar segments are secured inplace with a residue-free, burn-outplastic. The SCS occlusal screwsmust not be covered.
Tip: Overwaxing of the plasticcompounds ensures good accessof the flame later on in thesoldering investment.
Once the SCS positioning screwshave been loosened, the barframework is carefully removed.Stabilisation pins (048.208V4)are available for retaining thesynOcta® bar gold copings in thesoldering investment and arescrewed into place with the SCSpositioning screws. They ensurethat the gold copings areanchored accurately in thesoldering investment duringsoldering.
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To prevent possible distortion ofthe bar due to uneven preheatingwith the flame, the hardenedsoldering investment is preheatedto 930–1,100° F in a preheatingfurnace.
The bar must be devested andcleaned in an ultrasonic bath. Theoxides and soldering flux residuesare then removed in an acid bath.
Important: Due to the high preci-sion of the prefabricated caps,increased caution is requiredduring polishing. Therefore, under no circumstances, should a sandblaster be used.
Tip: To protect the margins, apolish protector (046.245) or ananalog can be screwed on duringpolishing. This reduces the risk of damage to the margins. It isadvisable to work under a stereo-microscope.
After the invested bar has beenpreheated, it is ready forsoldering. Once soldering hasbeen completed, the investmentshould be cooled to roomtemperature.
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It must be possible to repositionthe cleaned bar without tension onthe analogs, without it beingsecured with the SCS occlusalscrews when checking its fit.
Important: The SCS occlusalscrews that were used for solder-ing will be extremely oxidised andmust not be used to secure the barin the mouth. The bar must besecured in place with new SCSocclusal screws.
The finished synOcta® bar on theplaster model.
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Insertion of the barconstruction in themouthThe restoration is delivered to thedentist with the original abutments.
The healing caps are removedand the interior of the implant isthoroughly cleaned and dried.
The superstructure is removed fromthe master cast and the abutmentis unscrewed from the analog. The cleaned synOcta® abutment
is positioned without cement in theinternal octagon. The abutmentscrew is tightened using the SCSscrewdriver, ratchet (046.119) andtorque control device (046.049).
N.B.: The abutment must bepositioned in the octagon beforethe screw is tightened.
After osseointegration of theimplants, we recommend atightening torque of 35 Ncm wheninserting the abutment screws.
Torque = 35 Ncm!
The SCS occlusal screws aretightened with 15 Ncm on thesynOcta® abutment.
The bar is in situ with the new SCSocclusal screws.
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Positioning the barmatrixThe matrix must make use of theentire length of the bar. This helpsabsorb horizontal forces better.(Wirz, 1994)
Activator set for all bar matrices(046.150)
Deactivator for Dolder bar, mini(046.151)
Deactivator for Dolder bar,standard (046.152)
Varying the retention force of thebar matrix:Only the appropriate activator/deactivator may be used foractivating/deactivating the barmatrix.
■ To activate the matrix, press itswalls together with the activator.
■ To deactivate the matrix, pressits walls apart with thedeactivator.
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Initial situation edentulous: bar on synOcta®
Type of bar: soldered/laser-welded gold barAbutments and laboratory components gold copings Instruments
Insertion of abutmentsynOcta® abutment, 048.600 SCS screwdriver:
length 15mm: 046.400
length 21mm: 046.401
length 27mm: 046.402
and/or SCS screwdriver for handpiece adapter:
length 20mm: 046.410
length 26mm: 046.411
length 32mm: 046.412
Impression procedureOptional: Laboratory handpiecesynOcta® impression cap with integral 046.085positioning screw 048.010 for 046.410/411/412
or impression cap 048.017V4
+ synOcta® positioning cylinder 048.070V4
Production of master castsynOcta® analog 048.124
Production of superstructuresynOcta® gold coping, bar, 048.636
Dolder® bar, egg-shaped cross-section, mini, 048.411Dolder® bar matrix, mini, 048.413
Dolder® bar, egg-shaped cross-section, standard, 048.412Dolder® bar matrix, standard, 048.414
Stabilisation pin, 048.208V4
SCS Occlusal screw, 048.350V4
Insertion of final restorationSCS Occlusal screw, 048.350V4 Activator set, 046.150
Deactivator, mini, 046.151
Deactivator, standard, 046.152
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Fabrication of cast and laser-welded barsFabrication of barsusing the one-piececasting methodAs an alternative to the laser-welded or soldered gold bars, the dental technician now has achoice of synOcta® plastic coping,bar (048.660), and the Dolderbar variants standard (048.460)and mini (048.461) in burn-outplastic for the fabrication of a casttitanium bar (Wirz, 1997 andWirz et al., 1999).
The standard and mini titaniumbar matrices which fit the titaniumbar (from left to right).
The bar, composed of plastic partsand prepared for embedding.
The bar cast from pure titanium.
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Art. No. Article Dimension Material
048.660 synOcta® plastic coping Height 13.3mm, Burn-out plasticbridge/bar shortenable
048.460 Plastic bar, egg-shaped Height 3.0mm Burn-out plasticcross-section, standard Length 80.0mm
048.461 Plastic bar, egg-shaped Height 2.3mm Burn-out plasticcross-section, mini Length 80.0mm
048.470 Titanium bar matrix Height 4.5mm Titaniumstandard, incl. spacer Length 50.0mm
048.471 Titanium bar matrix, Height 3.5mm Titaniummini, incl. spacer Length 50.0mm
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Fabrication of laser-welded bars withtitanium componentsIn addition to the gold variant, thebar can also be composed ofprefabricated titanium parts usinga laser-welding technique.
A synOcta® titanium coping, bar(048.646) and the titanium barvariants standard (048.465) andmini (048.466) are available.
The standard and mini titaniummatrices which fit the titanium bar(from left to right).
The bar segments are fitted to themaster cast, allowing a minimumgap. Larger gaps are offset by theaddition of more titanium.
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The segments are welded togetherwith adequate argon gas rinsing.
Important: The soldering pointsmust not show any blue discol-oration. This type of discolorationindicates inadequate argon gasventilation and therefore oxygenuptake by the metal. This makesthe weld brittle and thereforeweakens the bar construction. Thelaser device operating instructionsmust be followed.
The finished polished titanium bar.
Art. No. Article Dimension Material
048.646 synOcta® Titanium coping Height 5.6mm Titaniumbar
048.465 Titanium bar, egg-shaped Height 3.0mm Titaniumcross-section, standard length 50.0mm
048.466 Titanium bar, egg-shapend Height 2.3mm Titaniumcross-section, mini length 50.0mm
048.470 Titanium bar matrix Height 4.5mm Titaniumstandard, length 50.0mmincl. spacer
048.471 Titanium bar matrix, Height 3.5mm Titaniummini, incl. spacer length 50.0mm
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Fabrication of the definitive bar prosthesis with metal reinforcement Once the bar has been tried in,the denture with metal reinforce-ment can be fabricated. The teeth are set up according tomodern full denture principles(e.g., Gerber et al.).
Once the wax-up denture hasbeen tried in, the teeth are securedin a plaster or silicone index. Toenable the index to be reposi-tioned accurately on the duplicatemodel, grooves are made in theground labial surface of themaster model.
The bar is then blocked out forduplicating. In order to do so, the bar is fitted onto the mastermodel.
Important: Before the bar sleeve is positioned, the spacer must befixed to the bar. This ensuresvertical translation of the denture.
The bar is then coated with a0.4 mm-thick wax sheet, which acts as a spacer. Labially andlingually, the wax is only extendedto the mucosa. Stops of approxi-mately 4 x 3 mm must be cut outto coincide with the height of thepremolars and the second molar.
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When the duplicating mould hasbeen removed, the index can befitted to the duplicate model. The plastic teeth are integratedinto the index and matched to theduplicate model.
The dimensions and thickness ofthe lingual surfaces of the teeth tobe built up are governed by theprevailing anatomical conditions.The retainers for the sleeve or ridershould also be positioned to pro-vide good mechanical retention.
The areas of the bar rider andstrengthener which contact thedenture acrylic must be silanized(e.g., Rocatec, Silicoater) or bepretreated with a primer.
Important: The bar sleeve andrider must not be soldered to themetal framework as this wouldprevent them being replaced at alater date. Also, any heattreatment would adversely affectthe elastic properties of thelamellae.
The finished metal-reinforcedjointed bar.
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Modification of a full lower denture in an implant/bar-borne hybrid denture
Important: The caps are suitableonly for impression-taking ofimplants with a head diameter of4.8 mm.
First, the healing caps areremoved from the implants and theimpression caps fitted with a snap-on mechanism. The relevant partof the existing denture is hollowedout.
Important: It must be possible to fitthe denture over the impressioncaps without making contact.
After adjusting the denture, theimpression is taken with theintegrated caps, using anelastomeric impression material(polyvinylsiloxane or polyetherrubber).
To protect the implant shoulder, the healing caps are screwedback onto the implants after theimpression-taking.
If the implant-borne anchorage ofan existing full denture is neces-sary, this can be fitted with a barconstruction after implantation andthe relevant healing time.
In this case, impression-taking iscarried out with the existingdenture in combination with one-part, orange colour-coded plasticimpression caps (048.092V4).
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The master cast is fabricated usingspecial hard plaster. One-part,orange, colour-coded synOcta®
analogs (048.142) are available.
These are placed in the plasticimpression caps situated in thedenture, and the master cast isthen fabricated in the conventionalway using special hard plaster,type 4 (DIN 13911). It isimportant to fix the bite height, as is usual with, for example, a denture relining.
After removing the denture and theimpression material from theplaster master cast, the barconstruction procedure is decided,and the denture is hollowed outaccordingly.
The bar is fabricated as describedon pages 11–14 and/or 18–21.
The bar matrices with the spacer(denture resilience) are positionedon the finished bar construction,and the undercut points andoutside of the matrices are blockedout with wax (to ensure that theycan be activated/deactivated).The denture is then adapted to thebar construction by polymerisationof the matrices. The denture is thenchecked for surplus plastic in theregion of the matrices and forfunction.
Important: This step is essential,because only in this way can theoptimum function of the integratedbar matrices (incl. ability toactivate/deactivate them) beensured. Unremoved plasticresidue may damage the barconstruction/implants.
Before the bar is fitted, thesynOcta® abutments (048.600) arescrewed into the implants with aforce of 35 Ncm.
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Relining an implant-borne bar denture
Hybrid dentures with resilientretention units should be examinedat intervals of approximately 3 months to enable harmfulexcursions of the denture to beeliminated in their early stages.
If the alveolar ridge resorbs after a prolonged wearing time, thebar-borne denture sinks. This leads to a loss of resilience of thematrices and so to greater stresson the retentive elements/implants.Relining then becomes necessary.
After impression-taking, the barstays in the denture, and thedental technician inserts the one-part orange synOcta® implant(048.142) into the bar caps.
The master cast is fabricated andprepared for relining in theconventional way.
Before relining, the bar is securedto the master cast with the SCSocclusal screws, the undercutpoints are blocked out with wax,and the corresponding spacer isfixed in the bar matrix. Relining is then carried out in the conven-tional way.
After relining, the spacer isremoved and the matrices arechecked for surplus plastic and for function.
Relining is carried out with the barin position.
First, the occlusal screws(048.350V4) are replaced byfixing pins (048.072V4). Thesefixing pins are made from plastic,have a snap-on mechanism andare colour-coded orange. They areused only to secure the bar on theimplants when taking a reliningimpression with the denture. Thefixing pins are intended for singleuse only.
Important: To preserve theresilience of the denture, thecorresponding spacer must beinserted between the bar andmatrix before impression-taking.
Important: This step is essential,because only in this way can theoptimum function of the relined,implant-borne bar denture beensured. Interference with thefunctioning of the joint mechanismmay damage the implant or barconstruction.
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Case presentation:Illustrations by courtesy of Dr. J. Röckl, private practice inTeningen, Germany
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Carisch H.Zahntechnische Aspekte bei derHerstellung einer implantatgetra-genen Unterkiefer-TotalprotheseQuintessenz Zahntech 9, 913–925 (1987)
Dolder E.StegprothetikDr. Alfred Hüthig Verlag, Heidelberg, 3. verbesserte und erweiterte Auflage (1971)
Dolder E., Wirz J.Die SteggelenkprotheseQuintessenz Verlag, Berlin (1982)
Jäger K., Wirz J.In-vitro-Spannungsanalysen an Implantaten in Abhängigkeitvon den hybridprothetischen SuprakonstruktionenZ Zahnärztl Implantol 9: 42–49(1993)
Lang N.P., Brägger U., Hämmerle C.H.F., Mombelli A.,Lehmann B., Weigel C.Das ITI® DENTAL IMPLANT SYSTEM: BehandlungsstrategieBasisinformation, Institut Straumann AG (1994)
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Spiekermann H.Die prothetische Behandlung Behandlungskonzept 1In: Rateitschak K.H., Wolf H.F.(Hrsg): Farbatlanten der Zahn-medizin 10, Implantologie, Thieme Stuttgart/New York, S. 150 (1994)
Tilse M., Dietrich P., Weingart D.Stegretinierte Hybridprothesen auf Bonefit-Implantaten unterVerwendung des Octa-SystemsImplantologie 1: 39–49 (1994)
Wirz J., Jäger K.Stegverankerungen implantat-getragener HybridprothesenQuintessenz 42, 2007–2014(1991)
Wirz J.Hybridprothese im atrophiertenUnterkieferIn: Foitzik Ch. (Hrsg): Das ITI® DENTAL IMPLANT SYSTEM.Schlütersche Verlagsanstalt, Hannover, S. 129 (1994)
Wirz J., Schmidli F., Schaardt S.Werkstoffkundliche Aspekte derHybridprothesenQuintessenz 45; 1131–1142(1994)
Wirz J., Jungo M., Isaak M.Renaissance der Stegprothetik mitneuen Werkstoffen und TechnologienTeil 1: Quintessenz 50, 611–617(1999)Teil 2: Quintessenz 50, 719–739(1999)
Wirz J.Titan - der Werkstoff für die Teil- und Hybridprothetik mit undohne ImplantateWirz J. u. Bischoff H. (Hrsg.): Titanin der Zahnmedizin S. 312–332,Quintessenzverlag, Berlin (1997)
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Instructions for dentists and dental techniciansTable of contents
Retentive anchors 29
■ Introduction 30
■ Fabrication of a new full lower denture with metal reinforcement 31and two gold matrices
■ Fabrication of a new full lower denture with metal reinforcement 36and two titanium matrices
■ Modification of an existing full lower denture in an 42implant-borne retentive anchor denture
■ Relining an implant-borne retentive anchor denture 44
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IntroductionPurposes of anchors:
■ Securing the prosthesis againstexcursive forces and those whichwould dislodge the saddles
■ Distribution of shear forces
■ To transfer the masticatory forcesas axially as possible from thedenture to the implant
Description/FunctionThe retentive anchor is assigned tothe movable attachments. Retentiveunits that permit rotary movementof the denture in one or moredirections and/or vertical transla-tional movements are termedmobile units.
The mobile connector shortens thelever arm of the tilting forcesexerted on the implant. Theimplants must always be placed atan angle of 90° to the occlusalplane to ensure that they areloaded axially. Precisely designedocclusal surfaces – balancedocclusion with freedom-in-centric(Geering et al., 1993) – andoptimum design of the denturefitting surface also influence thestability of the denture and thedistribution of the masticatoryforces (Worthington et al., 1992).We recommend that a newdenture always be fabricated aspart of the treatment plan or afterthe provision of implants(Mericske-Stern, 1988).
Indications forretentive anchors■ Extensive gaps which cannot be
bridged with bars
■ Insufficient space available (insuch cases, bars often cause theanterior section to be extendedtoo far lingually thus restrictingthe space available for thetongue and impeding itsfunctioning)
■ In cases of severely taperinganterior arches and/or jaws(Geering et al., 1993)
■ Single retentive anchors allowfor designs which are gentle onthe periodontium (hygienic)
Contraindications forretentive anchors■ Combined tooth-/implant-borne
restorations
■ In conjunction with attachmentsexhibiting a different degree ofresilience
■ If the implants are not vertical tothe occlusal plane
■ In cases where the implantshave been positioned in the archin such a way as to prevent atangential axis of rotation
■ In unfavourable ridge situations
Retentive anchors
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Fabrication of a full lower denture with a metalreinforcement and two gold matrices“Patient” initial situationEdentulous lower jaw with twoimplants replacing the canineswith retentive anchors (048.439).
Important: To ensure that theretentive anchors function perfectlyover a long period of time, theimplants must be placed asparallel as possible to one anotherand vertical to the occlusal planeto create a tangential axis ofrotation.
The retentive anchor has a squareneck to accommodate the driver,and can be changed if necessary.It is inserted into the implant with aforce of 35 Ncm. Measured fromthe upper edge of the implantshoulder, it is 3.4 mm high.
Driver (046.069) with “R.A”.marking (“Retentive Anchor”),retentive anchor (048.439), andtransfer pin (048.109) (from left toright).
Taking an impression of the retentive anchorThe impression is taken with anelastomeric impression material(polyvinylsiloxane or polyetherrubber) directly over the anchor,without any aids.
Important: In view of its lowresistance to tearing, a hydrocol-loid is not suitable for thisapplication.
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Producing the modelTransfer pins are positioned in the impression and the model isproduced in special, type 4 (DIN 13911) hard plaster. Theimpression of the retentive anchor,provides the square/spherical studof the transfer pin with sufficientretention in the impression.
To ensure stability, the productionand integration of a metalreinforcement in the full lowerdenture is recommended. Sufficientspace must be left for securing thematrices.
The teeth should be set up usingthe occlusal concept for fulldentures and in accordance withthe treatment plan and thenembedded in a flask.
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The working principleof the gold matrixThe gold matrix (048.410) consistsof a gold alloy (Elitor; composi-tion: Au 68.6%, Pt 2.5%, Pd4.0%, Ag 11.8%, Cu 10.6%, Zn 2.5%).The four lamellae function like aspring. The force required todisengage the attachment can beincreased by pressing the lamellaetogether (with the activator,046.120) or by spreading them(with the deactivator, 046.121).
Important: Only the activator/deactivator described should beused. Under no circumstancesshould the lamellae be bent with awax knife or the like. Should thelamellae be bent singly, the forcesno longer act uniformly on theretentive anchor, which may leadto unilateral stress. This may causethe lamellae to fracture or theretentive anchor to wear unevenly.The use of the activator/deactivator activates/deactivatesthe lamellae uniformly, which guar-antees that they retain the denturewith an equal amount of force.
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Before polymerising the matrices,the correct fit of the PVC ring onthe matrix must be checked. ThePVC ring must be flush with thelower edge of the matrix andleave the retention nut free for theacrylic. The ring acts as a spacerin the denture acrylic and givesthe lamellae unrestricted freedomof movement.
Should the PVC ring be missing or damaged, a new ring can beassembled with the aid of aspecial tool (046.153).
Once the flask has been opened,the deactivated gold matrices arepositioned on the transfer pinswith their axes aligned (parallel tothe path of insertion) and theundercuts are blocked out.
Important: Under no circumstancesshould the gold matrices besubjected to heat treatment (suchas soldering additional retainersor soldering the matrix to a metalframework), otherwise thelamellae on the matrix will notretain their elasticity.
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Setting up of the metal reinforce-ment and fixing of the matriceswith acrylic.
Completed denture. The denture is forwarded to the dentist with thematrices in a deactivated state.They are not activated until thedenture is fitted to the patient’smouth.
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“Patient” initial situationEdentulous lower jaw with twoimplants replacing the canineswith retentive anchors (048.439).
Model starting situation (proce-dure identical as described abovefor “Fabrication of a full lowerdenture with metal reinforcementand two gold matrices”).
The titanium matrix (048.450)consists of a titanium alloy (Ti-6Al-4V), hardness HV5 Vickers350–385. Individual components:threaded ring-spring-housing withretainer (from left to right).
Fabrication of a full lower denture with metalreinforcement and two titanium matrices
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Unlike the gold matrix, the titaniummatrix makes use of a spring witha defined extraction force of 700–1100g. If retention is lost, thespring can be replaced.
To replace the spring, the threadon the titanium matrix is un-screwed anticlockwise using aspecial screwdriver (048.452)and the spring is changed.
The threaded ring is then screwedback in place hand-tight.
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The titanium matrices can bepolymerised into place as follows:
Method A
Before positioning the matrices on the transfer pins on the model,the original threaded ring isunscrewed and replaced with aplastic threaded ring (048.454V4).The undercuts are blocked out with plaster. The plastic ring is3/100 mm wider in diameter thanthe titanium matrix and acts as aspacer for it. This prevents tootight a fit of the titanium threadedring on the polymerised acrylic.After polymerisation, the threadedring is replaced by the titaniumring once more.
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Method BThe denture is polymerised withspecial acrylic spacers only(048.451V4). First, the undercutsare blocked out with plaster. Oncethe denture is ready, the spacersare removed and the dentist canpolymerise the titanium matricesinto place directly in the patient’smouth. The spacers are also usedto produce the model for the metalreinforcement.
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Method CBefore being positioned on theedge of the threaded ring, thetitanium matrix is coated with athin film of die spacer. This ensuresthat the threaded ring can bereleased later on without excessiveforce having to be exerted.
Important: With all three methods,the titanium matrices (or spacers)must also always be positioned onthe transfer pins with their axesaligned (parallel to the path ofinsertion) and the undercutsblocked out.
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The finished denture with titaniummatrices integrated in the metalframework.
Important: Once the denture iscomplete, it must be checked toensure no acrylic has penetratedthe matrix. To do this, the threadedring should be removed and theinner configuration with the springshould be cleaned.
Removal of titaniummatrix from an existingdentureTo replace an entire titanium matrix,the threaded ring and spring mustfirst be removed. The tip of aspecial extractor (048.453) is thenheated over a Bunsen burner andscrewed into the matrix housing.The housing can then be with-drawn from the acrylic denture.
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Modification of an existing full lower denture in animplant-borne retentive anchor denture with gold matricesPolymerisation of the gold matricesin the patient’s mouth afterimplantation and osseointegration:
The existing full lower dentureprior to modification.
The retentive anchors are insertedinto the implants with a force of 35 Ncm. The existing denture isthen hollowed out in the region ofthe anchor. The opening createdallows the acrylic to flow in. Thegold matrices positioned on theanchor must not touch the dentureafter hollowing.
Prior to polymerising the goldmatrices (048.410), the correct fitof the PVC ring must be checked.The PVC ring must be flush withthe lower edge of the matrix andleave the retention element free forthe acrylic. Should the PVC ringbe missing or damaged, a newring can be inserted with the aid ofthe PVC ring mounting instrument(046.153). The ring acts as aspacer in the denture acrylic andenables the lamellae to functioncorrectly.
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After positioning on the retentiveanchors, a small piece of rubberdam is placed over the matrices.This prevents the acrylic fromflowing into the internal matrixconfiguration.
Important: The matrices must bealigned (parallel to the path ofinsertion).The prepared denture is then fixedin the mouth and the acrylic isflowed through the perforation.
The modified denture with thepolymerised gold matrices.
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Hybrid dentures with retentiveanchors should be checked atapproximately three-month inter-vals, to eliminate damagingdenture movements by appropriatemeasures at an early stage.
If the alveolar ridge resorbs after a prolonged wearing time, thedenture may sink. This leads to aloss of resilience of the matricesand so to greater stress on theretentive anchor/implants. Reliningthen becomes necessary.
Relining is carried out directly overthe retentive anchors. Care shouldbe taken to ensure that the dentureis sitting correctly (retentive anchor/matrix connection). The dentaltechnician then positions thetransfer pins (048.109) in thematrices (titanium or gold matrix)in the denture and produces therelining model (see also page 32,Producing the model).
After relining, the matrices shouldbe checked for acrylic that mayhave flowed into them and fortheir functionality. It must also bepossible to activate/deactivate thegold matrices. After polymerisa-tion, the titanium matrix is openedwith the relevant screwdriver(048.452) and the internalconfiguration is cleaned.
Important: These measures arevital, because only in this way isthe optimum function of the relined,implant-borne anchor dentureensured. If the function of the matrixis impeded, this can damage theimplant/anchor.
Relining of an implant-borne retentive anchor denture
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Edentulous: retentive anchorRetentive anchor with gold matrix Retentive anchor with titanium matrix
Choice of implant Solid screw implant Ø 4.1mm, 4.8mm; shoulder -Ø 4.8mm
Abutments and Instruments Abutments and Instrumentslaboratory parts laboratory parts
Insertion of abutmentsRetentive anchor Driver for retentive anchor Retentive anchor Driver for retentive anchor
048.439 046.069 048.439 046.069
ImpressionTransfer pin Transfer pin048.109 048.109
Production of denture Activator Titanium matrix ScrewdriverGold matrix 046.120 048.450 048.452048.410
Deactivator Spacer046.121 048.451V4
Stamp Threaded mounting046.153 ring
048.454V4
Insertion of final restoration
Activator Spring Screwdriver046.120 048.455V4 048.452
Deactivator046.121
Stamp Extractor046.153 048.453
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Case presentation:Illustrations by courtesy of Dr. G.S. Solnit D.D.S., M.S.,Beverly Hills, CA (USA)
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Retentive anchorsArt. No. Article Dimension Material
048.439 Retentive anchor Height 3.4mm Titanium
046.069 Retentive anchor driver Length 19.0mm Steel, stainless
048.109 Transfer pin for Length 18.0mm Steel, stainless retentive anchor
Gold matrix, activatable
048.410 Gold matrix for Height 2.3mm Elitor retentive anchor
046.153 PVC ring Length 31.0mm Steel, stainless/mounting instrument anodized aluminium
046.120 Activator für gold matrix Length 70.0mm Steel, stainless/plastic
046.121 Deactivator for Length 68.0mm Steel, stainless/plasticgold matrix
Titanium matrix with defined extraction force
048.450 Titanium matrix for Height 3.1mm Titanium alloyretentive anchor
048.451V4 Spacer for Height 3.5mm Plastictitanium matrix
048.452 Screwdriver for Length 60.0mm Steel, stainless/titanium matrix Alu, anodised
048.453 Extractor for Length 100.0mm Steel, stainlesstitanium matrix
048.454V4 Threaded mounting ring Height 2.2mm Plasticfor titanium matrix
048.455V4 Spring for 048.450 Steel, stainless
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References
Besimo Ch., Graber G., Schaffner Th.Hybridprothetische implantat-getragene Suprastrukturen imzahnlosen UnterkieferZWR, 100. Jahrg., Teil 1, Fall-planung, Nr.1 und 2 (1991)
Cendres & Métaux SA, CH-Biel-BienneKonstruktionselemente für dieProthetikProduktekatalog, Klasse 4 (1993)
Geering A. H., Kundert M.Total- und HybridtechnikFarbatlanten der Zahnmedizin, G. Thieme Verlag,Stuttgart, 2. Auflage (1993)
Lang N.P., Brägger U., HämmerleC.H.F., Mombelli A., Lehmann B.,Weigel C.Das ITI® DENTAL IMPLANT SYSTEM: BehandlungsstrategieBasisinformation, Institut Straumann AG (1994)
Mericske-Stern R., Geering A.H.Die Implantate in der Total-prothetikDie Verankerung der Total-prothese im zahnlosen Unter-kiefer durch zwei Implantate mit Einzelattachments.Schweiz Monatsschr Zahnmed,Vol. 98:8 (1988)
Mericske-Stern R.Eine klinische Longitudinalstudiemit Ergebnissen nach vier JahrenSchweiz Monatsschr Zahnmed,Vol. 98:9 (1988)
Mericske-Stern R.Clinical Evaluation of Overdenture Restorations Supported by Osseointegrated Titanium Implants: A Retrospective StudyInt J Oral Maxillofac Implants 5:375–383 (1990)
Mericske-Stern R.Implantate im zahnlosen UnterkieferSchweiz Monatsschr Zahnmed 10: 1215–1224 (1992)
Mericske-Stern R.Forces on Implants SupportingOverdentures:A Preliminary Study of Morphologic and Cephalometric ConsiderationsInt J Oral Maxillofac Implants 8:254–263 (1993)
Mericske-Stern R., Steinlin-Schaf-fer T., Marti P., Geering A. H.Periimplant Mucosal Aspects of ITI Implants supporting Overdentures. A 5 year longitudinal studyClinical Oral Implants Research 5:9–18 (1994)
Worthington P., Brånemark P.-I.Advanced Osseointegration Surgery: Applications in the Maxillofacial RegionQuintessence Publishing Co, In, Illinois, USA (1992)
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Instructions for dentists and dental technicians
Table of contents
Magnet 49
■ Introduction 50
■ Fabrication of a full lower denture with two magnets 53
■ Modification of an existing full lower denture to an 58implant-borne magnetic denture
■ Relining an implant-borne magnetic denture 60
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Titanmagnetics®
IntroductionThe functions of magneticanchorage units:
■ Securing the prosthesis againsttractive excursive forces andthose which would dislodge thesaddles
■ Distribution of shear forces
■ To transfer the masticatory forcesaxially from the denture to theimplant
Description/FunctionThe magnetic anchor is a dynamicanchor.
Retentive units which permit rotarymovement of the denture in one or more directions and/or verticaltranslational movements aretermed dynamic units.
The dynamic connector shortensthe lever arm of the tilting forcesexerted on the implant. Theimplants must always be placed atan angle of 90° to the occlusalplane to ensure that they areloaded axially. Precisely designedocclusal surfaces – balancedocclusion with freedom-in-centric(Geering et al., 1993) – andoptimum design of the denturefitting surface also influence thestability of the denture and thedistribution of the masticatoryforces (Worthington et al., 1992).We recommend that a new denturealways be fabricated as part ofthe treatment plan or after theprovision of implants (Mericske-Stern, 1988; Wirz et al., 1993,1994).
N.B.: Special precautions must betaken when working withmagnets. When carrying out MRI(Magnetic Resonance Imaging)diagnoses or taking X-rays, theimplant magnets and denture mustbe removed.
The titanium coating of theTitanmagnetics® inserts anddenture Titanmagnetics®, is upto 0.2 mm thick and air-tight,must not be sand-blasted underany circumstances, otherwisethe magnetic alloy (Sm2Co17)would be exposed. This destroysthe Titanmagnetics®, releasingcorrosion products into the body.
Titanmagnetics® must not besoldered or laser-welded. Extremeheat causes an irreversible lossof magnetic force and can damagethe titanium coating. DamagedTitanmagnetics® must be replacedimmediately.
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Magnetic fieldsIn the current literature, there is noevidence that permanent magneticfields with field strengths in theregion of 200–300 mT (Millitesla)cause local damage in humans.Titanmagnetics® generate apermanent magnetic field equivalentto the Earth’s natural magnetism.The mean field strengths are186 mT.
When the denture is in theresting position, the magneticfield is enclosed within itself (Cerny, 1979, 1980).
N.B.: Titanmagnetics® are part of atotal concept and must be usedonly with the corresponding STECO®
original parts and ITI instruments,as directed by the manufacturer.
The Titanmagnetics® System is aregistered trademark of STECO®.
0 1 9 7
Manufacturer:Steco-system-technik GmbH & Co. KGKollaustrasse 6D-22529 Hamburg, Germany
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Indications formagnets■ Extensive gaps which cannot be
bridged with bars
■ Insufficient space available (insuch cases, bars often cause theanterior section to be extendedtoo far lingually thus restrictingthe space available for thetongue)
■ In cases of severely taperinganterior arches and/or jaws
■ Periodontium-friendly designwith a magnet (hygienic);particularly suitable for elderlyand/or disabled patients)
Contraindications formagnets■ Combined tooth-/implant-borne
restorations
■ In conjunction with attachmentsexhibiting a different degree offreedom
■ If the implants are not vertical tothe occlusal plane
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Fabrication of a full lower denture with two Titanmagnetics®
“Patient” initial situationEdentulous lower jaw with twoimplants replacing the canines withTitanmagnetics® inserts (048.511).
Important: To ensure that theTitanmagnetics® insert functionperfectly over a long period oftime, the implants must be placedas parallel as possible to oneanother and vertical to the occlusalplane to create a tangential axisof rotation.
The Titanmagnetics® insert is fittedwith an external octagon toaccommodate the Titanmagnetics®
insert applicator, and can bereplaced as required. It is screwedinto the implant with a force of15–20 Ncm. Measured from theimplant shoulder, it is 3.25 mm highand has a diameter of 4.8 mm.
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Titanmagnetics® insert applicator(046.146) and Titanmagnetics®
insert (048.511).
Denture Titanmagnetics® (048.515),positioning cuff (048.516).
Titanmagnetics® impression cap(048.014), Titanmagnetics® modelimplant (048.121).
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Producing the master castThe Titanmagnetics® model implantsare then placed in the impressionposts and the master cast isfabricated using special hard,type 4 (DIN 13911) plaster.The analogues and impression postsare retained by magnetic force.
Tip: To ensure stability, the produc-tion and integration of a metalreinforcement in the full lowerdenture is recommended. Sufficientspace must be left for positioningthe denture Titanmagnetics®.
Impression-taking withthe Titanmagnetics®
insertThe impression is taken with anindividually produced plasticimpression tray with an elasto-meric impression material (poly-vinylsiloxane or polyether rubber)over the Titanmagnetics®
impression cap positioned onthe Titanmagnetics® insert.
Important: Due to its insufficienttensile strength and poor elasticrecoil, hydrocolloid is not suitablefor this application.
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The finished plaster model.
Before fabricating the wax model,the positioning cuffs are placedas a spacer between the Titan-magnetics® insert and the dentureTitanmagnetics®. The thin silicon lip is removedwith fine scissors/blade. With theaid of the positioning cuff, adefined area is left free aroundthe Titanmagnetics®, facilitatingthe easy, stress-free insertion andremoval of the denture.
The teeth should be set up usingthe occlusal concept for fulldentures and in accordance withthe treatment plan.
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Basalansicht der Wachsauf-stellung.
Denture Titanmagnetics® in situ.The space created by the use ofthe positioning cuff (resiliencecompensation) is clearly visible.
After the wax trial, the denture isfinished using, for example, theflask technique.
Important: After polymerisation,any plastic residue must be carefullyremoved from the shiny undersideof the denture Titanmagnetics®. The magnets must not be sand-blasted.
Basal view of wax model.
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Modification of an existing full lower denture on animplant-borne magnetic denture“Patient” initialsituationEdentulous lower jaw with twoimplants replacing the canineswith Titanmagnetics® inserts(048.511), inserted with a forceof 15–20 Ncm.
The positioning cuff (048.516) isplaced on the Titanmagnetics® insertand the denture Titanmagnetics®
is placed over that. The positioningcuff acts as a spacer and keepsthe two Titanmagnetics® approx.0.3 mm apart. This ensuresresilience of the denture on thegingiva. During intra-oral poly-merisation, the flexible lip of thepositioning cuff prevents liquidplastic from coming into contactwith the gingiva and implant.
N.B.: Titanmagnetics® must notbe ground.
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The denture is sufficiently hollow-out in the region of the magnetand perforated lingually. Thedenture is then placed in thepatient’s mouth.
The polymerised dentureTitanmagnetics® in situ.
Now, the denture Titanmagnetics®
can be secured with self-poly-merising plastic through the lingualperforation.
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Relining an implant-borne magnetic denture
Hybrid dentures with resilientretention units should beexamined at intervals of approxi-mately 3 months to ensure harmfulexcursions of the denture are beeliminated in their early stages.
If the alveolar ridge resorbs after a prolonged wearing time, theTitanmagnetics®-borne denturemay sink. This leads to a loss ofresilience by the matrices and soto greater stress on the Titan-magnetics®/implants. Reliningthen becomes necessary.
Important: Relining prevents thefriction to the Titanmagnetics®
caused by the constant mastica-tory movements, thus stoppingwear to the titanium coating andthe release of corrosion productsfrom the exposed magnets.
To ensure the resilience of thedenture, the Titanmagnetics® mustbe fitted with the positioningcuffs (048.516) before relining, as during fabrication/modification.To do so, the thin lips of thepositioning cuffs are removed withscissors/blade and the cuffsare placed in the Titanmagnetics®
in the denture (048.515) andsecured in the spaced createdduring fabrication/modification.
Impression-taking for relining takesplace directly over the Titan-magnetics® insert in the implant.The correct fit of the denture(Titanmagnetics® insert/positioningcuff/denture Titanmagnetics®)should be ensured.
The dental technician then checksthe Titanmagnetics® model implant(048.121) in the denture Titan-magnetics® in the denture, andfabricates the relining model(see also page 6, Producing themaster cast).
After relining, the positioning cuffsare removed and the denture ischecked for surplus plastic in theregion of the Titanmagnetics® andfor their function.
Important: This step is essential,because only in this way can theoptimum function of the relined,implant-borne denture Titan-magnetics® be ensured. Unremovedplastic residue may damagethe Titanmagnetics®/implant andtherefore lead to failure.
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Edentulous: Titanmagnetics®
Abutments and laboratory parts Instruments
Choice of implant Solid-screw implant Ø 4.1mm, 4.8mm; shoulder-Ø 4.8mm
Insertion of abutment Titanmagnetics® insert Titanmagnetics® insert applicator 048.511 046.146
Ratchet 046.119
with torque control device046.049
Impression procedure Titanmagnetics® impression cap048.014
Production of master cast Titanmagnetics® model implant048.121
Production of superstructure Positioning cuff048.516
Denture Titanmagnetics®
048.515
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Titanmagnetics®
Art. No. Article Dimension Material
048.511 Titanmagnetics® insert Height 3.25mm Titanium housingØ 4.8mm
046.146 Titanmagnetics® Height 18.0mm Titanium housinginsert applicator
048.014 Titanmagnetics® Height 7.0mm Titanium housingimpression cap
048.121 Titanmagnetics® Height 9.0mm Titanium housingmodel implant
048.516 Positioning cuff Height 0.3mm Dental siliconØ 15,0mm
048.515 Denture Titanmagnetics® Height 2.65mm Titanium housingØ 4.8mm
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Case presentation:Illustrations by courtesy of Prof. Dr. J. Wirz, Basel, Switzerland
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References
Cerny R.The biological effects of implanted magnetic fieldsPart 1, Aust. Orthod. J., 64 (1979)Part 2, Aust. Orthod. J., 6,114–121 (1980)
Jäger K., Wirz J.Unterkiefer-Hybridprothesen mitvier Implantaten. Eine In-vitro-SpannungsanalyseSchweiz. Monatsschr. Zahnmed.,104, 1489–1494 (1994)
Wirz J., Jäger K., Schmidli F.Magnetverankerte (implantat-gesicherte) Totalprothesen – Ein Beitrag zur AltersprothetikSchweiz. Monatsschr. Zahnmed.104, 1235–1244 (1994)
Tiller R. et al.Das implantatgetragene Magnet-attachment - eine sinnvolle Alter-native in der HybridprothetikImplantologie 1, 47–55, (1995)
Stemmann, H. und Stemmann, H. jun.Behandlung mit magnetretinierterImplantatprothetik – ein Fall-berichtZahnärztliche Praxis 46, 10–11,(1995)
Vesper M. et al.Titanmagnetics® als Hilfsmittel zur Verankerung bei anatomischschwieriger Situation im Ober-kieferZahnärztl. Implantologie 11, 196–198 (1995)
Wirz J., Lopez S., Schmidli F.Magnetverankerungen auf ImplantatenTeil I: BestandsaufnahmeQuintessenz 4, 579–588 (1993)
Wirz J., Lopez S., Schmidli F.Magnetverankerungen auf ImplantatenTeil II: KorrosionsverhaltenQuintessenz 5, 737–749 (1993)
Wirz J., Jäger K., Schmidli F.Magnetverankerungen auf ImplantatenTeil III: Schlussfolgerungen und klinische EmpfehlungenQuintessenz 6, 891–898 (1993)
Wirz J.Titan - der Werkstoff für die Teil- und Hybridprothetik mit und ohne ImplantateWirz J. u. Bischoff H. (Hrsg.): Titanin der Zahnmedizin S. 323–342;Quintessenzverlag, Berlin (1997)
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