Philosophies of Occlusion for Implants

Implant Occlusion

Single CrownSingle Crown Fixed Partial DenturesFixed Partial Dentures Full arch prostheses (screw retained)Full arch prostheses (screw retained) OverdenturesOverdentures

Many Philosophies of Occlusion

NoNo definitivedefinitive scientificscientific studiesstudies to prove: to prove: one type of one type of tooth formtooth form one type of one type of occlusal schemeocclusal scheme to be clearly to be clearly preferredpreferred by patients by patients to be more to be more efficientefficient than another than another

Tooth Forms Occlusal Schemes

AnatomicAnatomic Non AnatomicNon Anatomic

Canine Guidance Canine Guidance (Mutually Protected)(Mutually Protected)

Group FunctionGroup Function Lingualized Lingualized

(Balanced)(Balanced) MonoplaneMonoplane

Denture Tooth Forms and Denture Tooth Forms and Occlusal FormsOcclusal Forms

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Occlusion & Implants

Evidence Based Review Evidence Based Review Taylor, Wiens et al. J Prosthet Dent 2005;94:555-560Taylor, Wiens et al. J Prosthet Dent 2005;94:555-560

No Preferred occlusal schemeNo Preferred occlusal scheme Clinicians advocate axial loading of implants, Clinicians advocate axial loading of implants,

but no evidence, but no evidence, at present,at present,

demonstrating benefitsdemonstrating benefits

Occlusion & Implants

Evidence Based Review Evidence Based Review Taylor, Wiens et al. J Prosthet Dent 2005;94:555-560Taylor, Wiens et al. J Prosthet Dent 2005;94:555-560

No evidence No evidence at presentat present that that progressive occlusal loading of implant progressive occlusal loading of implant

is beneficialis beneficial occlusal overload is detrimental to occlusal overload is detrimental to

implantsimplants

Absence of Scientific Evidence

Not proof against!Not proof against!

Follow best available clinical Follow best available clinical principlesprinciples

Do not build in heavy non-axial Do not build in heavy non-axial loading or overloadingloading or overloading

Clinical Principles for Occlusion

Based on Clinical ExperienceBased on Clinical Experience

Not Scientific EvidenceNot Scientific Evidence

General Principles

Improve denture stability or axial Improve denture stability or axial loading of single teethloading of single teeth

Centric contacts on flat surfaces, Centric contacts on flat surfaces, not inclinesnot inclines

General Principles

a

1-2 mmNonanatomicsetup1-2 mmAnatomic setupCenter overlower ridge

Posterior Posterior Overjet to Overjet to Avoid Cheek Avoid Cheek BitingBiting

General Principles

Improve denture Improve denture stability or single stability or single tooth loadingtooth loading

Center occlusal contacts Center occlusal contacts over ridgeover ridge

Simultaneous posterior Simultaneous posterior contacts in centriccontacts in centric

General Occlusal Principles

For overdentures or full arch For overdentures or full arch prostheses opposing a CD:prostheses opposing a CD:

No anterior contacts in centricNo anterior contacts in centric Minimizes anterior resorptionMinimizes anterior resorption

Grazing anterior contacts in Grazing anterior contacts in excursionsexcursions IncisingIncising

Occlusal Schemes

Canine GuidanceCanine Guidance Group FunctionGroup Function LingualizedLingualized MonoplaneMonoplane Dentures

Single Teeth

FPD’s

Crowns or FPD’s

Either canine guidance or group function Either canine guidance or group function works - no preferenceworks - no preference

Use what the patient has Use what the patient has Use what would be easiestUse what would be easiest

Overdentures or

Full Arch Prostheses

ALLALL Occlusal Schemes Devised to Occlusal Schemes Devised to Maximize Denture StabilityMaximize Denture Stability

Lingualized Occlusion

Maxillary cusped toothMaxillary cusped tooth Mandibular cuspless or shallow cusped Mandibular cuspless or shallow cusped

toothtooth Maxillary lingual cusp Maxillary lingual cusp balancesbalances

like a mortar in a pestle like a mortar in a pestle

Lingualized Occlusion

• Lingual cusp contacts Lingual cusp contacts opposing central fossaeopposing central fossae

• Mandibular cuspal inclines Mandibular cuspal inclines are shallow (0°, 10°)are shallow (0°, 10°)

• Less lateral displacementLess lateral displacement

Lingualized OcclusionHow Stability is Improved

Simultaneous bilateralSimultaneous bilateral anterior and posterior in anterior and posterior in all all excursionsexcursions

Tilting forces theoretically Tilting forces theoretically neutralizedneutralized

Enter Bolus Exit Balance?

Many patients chew bilaterallyMany patients chew bilaterally Biting forces maximum close to intercuspation Biting forces maximum close to intercuspation

(where balance most effective)(where balance most effective) Non-functional aspects (swallow)Non-functional aspects (swallow)

Point of Loading Affects Stability

Browning, 1986Browning, 1986

Loaded centrally, Loaded centrally, M, D, L,M, D, L, BB

BB caused unseating caused unseating

Central loading better than Central loading better than distal loadingdistal loading

MM

DD

LL

BBCC

Lingualized Contacts

Balancing SideBalancing Side

Working SideWorking Side

Only buccal cusp Only buccal cusp contact is inner contact is inner incline of incline of mandibular teeth mandibular teeth (balancing)(balancing)

‘IIF’ Rule

a

Inner Inclines (inside of cusp)Outer Inclines(outside of cusp)

B LBL

WorkingContacts IIFIIF you have contacts on the you have contacts on the IInner nner IInclines of nclines of FFunctional cusps unctional cusps

they are balancing contactsthey are balancing contacts

Test!

Rules for Balancing Contacts Balancing contacts should be lines, not Balancing contacts should be lines, not

pointspoints Balancing contacts should never be heavier Balancing contacts should never be heavier

than working contactsthan working contacts

Balanced Occlusion (Lingualized)

Indirect evidence that balanced occlusion may:Indirect evidence that balanced occlusion may: reduce ridge resorption reduce ridge resorption ((Maeda & WoodMaeda & Wood , 1989), 1989)

allow for increased functional forces in allow for increased functional forces in excursions excursions ((Miralles et al, 1989)Miralles et al, 1989)

Lingualized Cusp Angles

Always use steep cusped Always use steep cusped maxillary tooth (33°)maxillary tooth (33°)

When condylar guidance is When condylar guidance is steeper use more cusp angle steeper use more cusp angle in mandible (10°)in mandible (10°)

Lingualized Occlusion

Balance cannot be set without an articulatorBalance cannot be set without an articulator Clinical remount on an articulator - fewer Clinical remount on an articulator - fewer

adjustmentsadjustments

Condylar Inclination Posterior teeth separate as working Posterior teeth separate as working

condyle moves forward (and condyle moves forward (and downward)downward)

Anterior teeth contact Anterior teeth contact Closer to condyle, more separationCloser to condyle, more separation More anterior separation of More anterior separation of

Premolars if steep anterior guidancePremolars if steep anterior guidance

Effect of Mandible Moving Downward During Excursions

Maintaining Balancing Contacts

Change occlusal plane angleChange occlusal plane angle Increase compensating curvesIncrease compensating curves Increase cusp angles or effective cusp Increase cusp angles or effective cusp

anglesangles

Checking for Balance

Feels Feels SmSmoooooooooooothth in excursions in excursions

- Fingers on max. canines- Fingers on max. canines - Check on articulator- Check on articulator

Assess Contacts: Centric StopsCentric Stops ExcursionsExcursions

Improving Denture Occlusion

Most important cusp - maxillary lingual Most important cusp - maxillary lingual Mandibular buccal cusps more lateral - more Mandibular buccal cusps more lateral - more

tippingtipping

When Not to Balance

Difficulty in obtaining repeatable centric Difficulty in obtaining repeatable centric record record incoordination, incoordination, muscle splintingmuscle splinting

Dramatic malocclusionsDramatic malocclusions Severe ridge resorption Severe ridge resorption

lateral forces displace the denturelateral forces displace the denture Implants tend to negate this factorImplants tend to negate this factor

Monoplane Occlusion

Cuspless teeth set on a flat plane with 1.5- 2 Cuspless teeth set on a flat plane with 1.5- 2 mm overjetmm overjet

No cusp to fossa relationship No cusp to fossa relationship No anterior contacts present in centric No anterior contacts present in centric

positionposition No overbiteNo overbite

Monoplane OcclusionHow Stability is Improved

Elimination of cuspsElimination of cusps

Lateral forces reduced, improving stabilityLateral forces reduced, improving stability

Simplifies denture tooth arrangementSimplifies denture tooth arrangement

Monoplane Occlusion With Condylar Inclination

Monoplane OcclusionWith Condylar Inclination

Ensure Teeth Set Over Ridge

Minimize tilting/tippingMinimize tilting/tipping Maximize stabilityMaximize stability Minimize contacts on Minimize contacts on buccalbuccal of flat cusps of flat cusps

Monoplane Occlusion Functional, but unestheticFunctional, but unesthetic

Not balanced - flatNot balanced - flat Zero degree teeth can be Zero degree teeth can be

balanced if condylar balanced if condylar inclinations are shallowinclinations are shallow

Monoplane Occlussion - When? Jaw size discrepancies, malocclusions Jaw size discrepancies, malocclusions

cross-bite, Cl II, IIIcross-bite, Cl II, III Minimal ridgeMinimal ridge

reduces horizontal forcesreduces horizontal forces implants helpimplants help

Uncoordinated jaw movementsUncoordinated jaw movements

Summary

No definitive studies to show one type No definitive studies to show one type of occlusion is bestof occlusion is best

Follow established clinical principlesFollow established clinical principles Assess each case - adapt to clinical Assess each case - adapt to clinical

situationsituation Continue to read the literatureContinue to read the literature