15.concepts of complete denture occlusion

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15. Concepts of Complete Denture 15. Concepts of Complete Denture OcclusionOcclusion

Michael Hamada DDSMichael Hamada DDSDivision of Advanced Prosthodontics, Division of Advanced Prosthodontics, Biomaterials and Hospital DentistryBiomaterials and Hospital Dentistry

UCLA School of DentistryUCLA School of Dentistry

This program of instruction is protected by copyright ©. No portion of This program of instruction is protected by copyright ©. No portion of this program of instruction may be reproduced, recorded or transferred this program of instruction may be reproduced, recorded or transferred by any means electronic, digital, photographic, mechanical etc., or by by any means electronic, digital, photographic, mechanical etc., or by any information storage or retrieval system, without prior permission.any information storage or retrieval system, without prior permission.

Mobile bases on mucosaMobile bases on mucosa Teeth move as an unitTeeth move as an unit Malocclusion affects Malocclusion affects

entire base immediatelyentire base immediately Non-vertical forces affect Non-vertical forces affect

all teeth and is traumaticall teeth and is traumatic Incising affects all teeth Incising affects all teeth

attached to baseattached to base Bilateral balance is often Bilateral balance is often

desired for base stabilitydesired for base stability Decreased tactile senseDecreased tactile sense

Retained in PDLRetained in PDL Units move Units move

independentlyindependently Malocclusion effects not Malocclusion effects not

immediateimmediate Non-vertical forces Non-vertical forces

affect only teeth affect only teeth involved and usually involved and usually well toleratedwell tolerated

Incising doesn’t affect Incising doesn’t affect posteriorsposteriors

Bilateral balance is rareBilateral balance is rare Tactile sensitivityTactile sensitivity

Natural DentitionNatural Dentition Denture “Dentition”Denture “Dentition”

Differences between Natural and Complete Differences between Natural and Complete Denture OcclusionDenture Occlusion

Goals of Complete Denture OcclusionGoals of Complete Denture Occlusion Minimize trauma to the Minimize trauma to the

supporting structuressupporting structures Preserve remaining structuresPreserve remaining structures Enhance stability of the Enhance stability of the

denturesdentures Facilitate esthetics and speechFacilitate esthetics and speech Restore mastication efficiency Restore mastication efficiency

to a reasonable levelto a reasonable level

Types of Complete Denture OcclusionTypes of Complete Denture Occlusion

Bilateral balanceBilateral balance NeutrocentricNeutrocentric

We prefer bilateral balance because this type of occlusal We prefer bilateral balance because this type of occlusal arrangement limits tipping of the dentures during arrangement limits tipping of the dentures during parafunctional movements,parafunctional movements,

Bilateral Balanced Denture OcclusionBilateral Balanced Denture Occlusion

The stable simultaneous contact of The stable simultaneous contact of opposing upper and lower teeth in opposing upper and lower teeth in centric relation position with a smooth centric relation position with a smooth bilateral gliding contact to any eccentric bilateral gliding contact to any eccentric position within the normal range of position within the normal range of mandibular function, developed to mandibular function, developed to lessen or limit tipping or rotation of the lessen or limit tipping or rotation of the denture bases in relation to the denture bases in relation to the supporting structures.supporting structures.

Bilateral Balanced Denture OcclusionBilateral Balanced Denture Occlusion

Traditionally bilateral balance was Traditionally bilateral balance was achieved with anatomic posterior achieved with anatomic posterior denture teeth. However, it can be denture teeth. However, it can be achieved with nonanatomic teeth using achieved with nonanatomic teeth using balancing ramps or by manipulating balancing ramps or by manipulating the compensating curve.the compensating curve.

Bilateral Balanced Denture Occlusion Bilateral Balanced Denture Occlusion with Anatomic Posterior Denture Teethwith Anatomic Posterior Denture Teeth

Bilateral Posterior Bilateral Posterior Centric ContactCentric Contact

Centralized ForcesCentralized Forces ““Balanced” Occlusion Balanced” Occlusion

to minimize tipping to minimize tipping

ProtrusiveProtrusive BalancingBalancing WorkingWorking

CentricCentric

Monoplane with Balancing RampsMonoplane with Balancing RampsWorkingWorking BalancingBalancing

Bilateral balanced occlusion can Bilateral balanced occlusion can also be obtained with also be obtained with nonanatomic posterior teeth if nonanatomic posterior teeth if balancing ramps are employed. In balancing ramps are employed. In all lateral excursions you should all lateral excursions you should observe at least three points of observe at least three points of contact bilaterally if bilateral contact bilaterally if bilateral balance is to be achieved. balance is to be achieved.

ProtrusiveProtrusive

Lingualized Opposing Monoplane with Balancing Lingualized Opposing Monoplane with Balancing RampsRamps

A similar concept is used when lingualized maxillary teeth oppose nonanatomic teeth in the mandible.In all lateral A similar concept is used when lingualized maxillary teeth oppose nonanatomic teeth in the mandible.In all lateral excursions you should observe at least three points of contact bilaterally to maintain bilateral balance. excursions you should observe at least three points of contact bilaterally to maintain bilateral balance.

WorkingWorking BalancingBalancing

Monoplane Occlusion Monoplane Occlusion (Neutrocentric Concept)(Neutrocentric Concept)

This concept of occlusion assumes that the anterior-This concept of occlusion assumes that the anterior-posterior plane of occlusion should be parallel to the posterior plane of occlusion should be parallel to the denture foundation area and not dictated by condylar denture foundation area and not dictated by condylar inclination.inclination.The plane of occlusion is completely flat and level. There is The plane of occlusion is completely flat and level. There is no curve of Wilson or Curve of Spee (compensating curve) no curve of Wilson or Curve of Spee (compensating curve) incorporated into the set up.incorporated into the set up.There is no vertical overlap of the anterior teeth.There is no vertical overlap of the anterior teeth.When using this concept of occlusion the patient is When using this concept of occlusion the patient is instructed not to incise the bolus. With this tooth instructed not to incise the bolus. With this tooth arrangement DeVan noted that “the patient will become a arrangement DeVan noted that “the patient will become a chopper, not a chewer or a grinder.”chopper, not a chewer or a grinder.”

Monoplane OcclusionMonoplane Occlusion(Neutrocentric Concept)(Neutrocentric Concept)

CentricCentric BalancingBalancing

At balancing and protrusive positions there is separation of At balancing and protrusive positions there is separation of the denture teeth in the posterior regions leading to tipping the denture teeth in the posterior regions leading to tipping of the dentures. This may be disadvantageous in the of the dentures. This may be disadvantageous in the patients exhibiting parafunctional grinding habits patients exhibiting parafunctional grinding habits

Hanau’s QuintHanau’s Quint

Five Factors Affecting Occlusal BalanceFive Factors Affecting Occlusal Balance• Condylar InclinationCondylar Inclination• Incisal GuidanceIncisal Guidance• Occlusal Plane InclinationOcclusal Plane Inclination• Compensating CurveCompensating Curve• Cuspal InclinationCuspal Inclination

Inter-relationship of these five factors may Inter-relationship of these five factors may be described bybe described by Theilman’s Formula Theilman’s Formula

In order to maintain a balanced occlusion:In order to maintain a balanced occlusion:

C=Condylar Inclination

OccPlane

x Incisal Guidance

x Cuspal Inclination x CompCurve

Of these five factors, the patient presents you with Condylar Of these five factors, the patient presents you with Condylar InclinationInclination

Occlusal Plane cannot be altered substantially since functional Occlusal Plane cannot be altered substantially since functional requirements dictate its position and orientationrequirements dictate its position and orientation

The remaining three factors can be controlled by the dentistThe remaining three factors can be controlled by the dentist

OccPlane

x Incisal Guidance

x Cuspal Inclination x CompCurve

Factors controlled by the dentistFactors controlled by the dentist

Of these five factors, the patient presents you with Condylar Of these five factors, the patient presents you with Condylar InclinationInclination

Occlusal Plane cannot be altered substantially since functional Occlusal Plane cannot be altered substantially since functional requirements dictate its position and orientationrequirements dictate its position and orientation

The remaining three factors can be controlled by the dentistThe remaining three factors can be controlled by the dentist

OccPlane

x Incisal GuidanceIncisal Guidance

x Cuspal InclinationCuspal Inclination x CompCurveCompCurve

Factors controlled by the dentistFactors controlled by the dentist

Hanau’s QuintHanau’s Quint Within the confines of esthetics and phonetics, Within the confines of esthetics and phonetics,

minimize Incisal Guidance in Complete Dentures to minimize Incisal Guidance in Complete Dentures to minimize inclined tipping forcesminimize inclined tipping forces

Adjust remaining factors to maintain balanceAdjust remaining factors to maintain balance

OccPlane

x Incisal GuidanceIncisal Guidance

x Cuspal InclinationCuspal Inclination x CompCurveCompCurve

LingualizedLingualized Monoplane – neutrocentricMonoplane – neutrocentric Monoplane with balancing rampsMonoplane with balancing ramps Lingualized opposing monoplaneLingualized opposing monoplane Semi-anatomicSemi-anatomic Anatomic (30 degree)Anatomic (30 degree)

Posterior Tooth FormsPosterior Tooth Forms

Anatomic Tooth FormsAnatomic Tooth Forms

Nonanatomic Tooth FormsNonanatomic Tooth Forms

Semi-anatomic Tooth FormsSemi-anatomic Tooth Forms

Goals of Complete Denture OcclusionGoals of Complete Denture Occlusion Minimize trauma to the Minimize trauma to the

supporting structuressupporting structures Preserve remaining Preserve remaining

structuresstructures Enhance stabilityEnhance stability Esthetics, Speech and Esthetics, Speech and

MasticationMastication Enhance masticationEnhance masticationIn addition we would like to decrease lateral In addition we would like to decrease lateral forces to the residual ridges.forces to the residual ridges.

General Concepts of Denture OcclusionGeneral Concepts of Denture Occlusion Common FeaturesCommon Features

• Functional anatomy is the main determinant of denture tooth positionFunctional anatomy is the main determinant of denture tooth position• Simultaneous, bilateral posterior contact in centric relation (centric occlusion)Simultaneous, bilateral posterior contact in centric relation (centric occlusion)• Centralization of centric occlusal forces over the mandibular residual ridgesCentralization of centric occlusal forces over the mandibular residual ridges

Buccal-LinguallyBuccal-Lingually Anterior-PosteriorlyAnterior-Posteriorly

Is “Balance” necessary?Is “Balance” necessary?

Balanced Balanced occlusion occlusion

Non-balanced Non-balanced occlusionocclusionvsvs

Protrusive positionProtrusive position Protrusive positionProtrusive position

Is “Balance” Necessary?Is “Balance” Necessary?

““Bolus in”Bolus in”

““Balance out”Balance out”

““Society is made up of happy neurotics, Society is made up of happy neurotics, unhappy neurotics, and a few psychotics, unhappy neurotics, and a few psychotics,

and some of each become partially or and some of each become partially or totally edentulous.”totally edentulous.”

Theodore Berg, Jr., D.D.S.Theodore Berg, Jr., D.D.S.

* * Balance is for Parafunctional Balance is for Parafunctional Movements Movements

Is “Balance” Necessary?Is “Balance” Necessary?Tests of Balanced and Non-balanced Tests of Balanced and Non-balanced

OcclusionsOcclusionsTrapozzano, V. R.: JPD 10: 476-487, 1960.Trapozzano, V. R.: JPD 10: 476-487, 1960.

1) No patient preference1) No patient preference 2) Balanced slightly more efficient2) Balanced slightly more efficient 3) Percentage of patients using 3) Percentage of patients using

eccentric movements during eccentric movements during mastication is smallmastication is small

““Simplification of Occlusion in Complete Simplification of Occlusion in Complete Denture Practice: Posterior Tooth Denture Practice: Posterior Tooth

Form and Clinical Procedures”Form and Clinical Procedures”Dale Smith: DCNA 14: No. 3; July, 1970.Dale Smith: DCNA 14: No. 3; July, 1970.

1) Advocates cuspless teeth primarily 1) Advocates cuspless teeth primarily for ease of usefor ease of use

2) May use balanced occlusion but 2) May use balanced occlusion but can’t prove that it is necessarycan’t prove that it is necessary

Balance and the Monoplane OcclusionBalance and the Monoplane Occlusion

Minimize vertical overlap within the dictates of esthetics and phonetics

Balance and Monoplane OcclusionBalance and Monoplane Occlusion

Minimize vertical overlap within the dictates of esthetics and phonetics

Bilateral BalanceBilateral Balance

Anatomic posterior teeth vs LingualizedAnatomic posterior teeth vs Lingualized

Bilateral balance with anatomic denture teethBilateral balance with anatomic denture teeth

Balancing sideBalancing side

Lingualized OcclusionLingualized Occlusion

LingualizedLingualizedConventionalConventional

Centric OcclusionCentric Occlusion

Theoretically, there should be Theoretically, there should be less lateral displacement of the less lateral displacement of the denture and less lateral forces denture and less lateral forces during function when using during function when using lingualized posterior denture lingualized posterior denture teeth.teeth.

Setting the Maxillary PosteriorsSetting the Maxillary Posteriors

The lingual cusp tips The lingual cusp tips should be in contact with should be in contact with the central fossae of the the central fossae of the opposing mandibular opposing mandibular teeth. The cuspal inclines teeth. The cuspal inclines of the mandibular teeth of the mandibular teeth are relatively flat, are relatively flat, resulting in potentially resulting in potentially less lateral forces and less lateral forces and displacement during displacement during function. function.

Balancing SideBalancing Side

Working SideWorking Side

Centric OcclusionCentric Occlusion

Good estheticsGood esthetics Freedom of non-anatomic Freedom of non-anatomic

teethteeth Potential for bilateral Potential for bilateral

balancebalance Centralizes vertical forcesCentralizes vertical forces Minimizes tipping forcesMinimizes tipping forces Facilitates bolus Facilitates bolus

penetration (mortar and penetration (mortar and pestle effect)pestle effect)

High esthetic demandsHigh esthetic demands Severe mandibular ridge Severe mandibular ridge

atrophyatrophy Displaceable supporting Displaceable supporting

tissues tissues MalocclusionMalocclusion Previous successful denture Previous successful denture

with Lingualized Occlusionwith Lingualized Occlusion

Indications for useIndications for use AdvantagesAdvantagesLingualized OcclusionLingualized Occlusion

Investigators have Investigators have notnot shown one type of shown one type of denture occlusion to be : denture occlusion to be : • superior in functionsuperior in function• safer to oral structuressafer to oral structures• more acceptable to patientsmore acceptable to patients

Complete Denture OcclusionComplete Denture Occlusion

Complete Denture OcclusionComplete Denture Occlusion Neuromuscular control may be the Neuromuscular control may be the

single most significant factor in the single most significant factor in the successful manipulation of complete successful manipulation of complete dentures under functiondentures under function

Tongue function Tongue function and denture and denture wearing experiencewearing experience

15.concepts of complete denture occlusion

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