22.criteria for posterior tooth selection

22. Criteria for Posterior Tooth Selection22. Criteria for Posterior Tooth Selection

Michael Hamada DDSMichael Hamada DDSandand

John Beumer III, DDS, MSJohn Beumer III, DDS, MSDivision of Advanced Prosthodontics, Division of Advanced Prosthodontics, Biomaterials and Hospital DentistryBiomaterials and Hospital Dentistry

UCLA School of DentistryUCLA School of Dentistry

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14. Posterior Tooth Selection14. Posterior Tooth SelectionLingualizedLingualized

Lingualized vs

monoplane

Monoplane Monoplane AnatomicAnatomic

Semi-anatomicSemi-anatomic

14. Posterior Tooth Selection14. Posterior Tooth Selection

Criteria Resorbed or flabby ridges Physical condition of the patient Patients who clench or brux Previous denture occlusion Ridge relationship Immediate dentures

14. Posterior Tooth Selection14. Posterior Tooth SelectionResorbed or flabby ridgesSuch conditions, as demonstrated in these two patients, make it difficult to obtain accurate intraoral records and permit movement of the denture bases during function. The poorer the record base stability, the less cusp height is indicated.Exception: Some patients with highly resorbed ridges retain superb tongue control and a reasonably stable denture base. If they are vertical chewers, rather than wide envelope grinders, they will prefer and be able to handle cusp fossa teeth. Such patients are ideal candidates for lingualized occlusal schemes.


Patients with poor neuromuscular control have difficulty accommodating to anatomic occlusions. They are best served with monoplane occlusal schemes.

Physical condition of the patient

Chronic bruxers and grindersChronic bruxers and grinders


Anxious, nervous individuals are more apt to brux, which can be especially traumatic to the supporting structures when anatomic posterior denture teeth are used. They are best served with monoplane occlusal schemes.

Previous denture occlusionPrevious denture occlusion


If the present dentures have anatomic teeth which have not been severely ground or worn and the alveolar ridges are not severely resorbed, anatomic teeth can be used. If the existing denture teeth have been worn flat, nonanatomic teeth may be a better choice.

Ridge relationshipRidge relationship


A skeletal class II relationship requires nonanatomic posterior teeth or cusp to open fossae teeth which permit multiple contact positions without occlusal interferences.

When the greater width of the mandibular arch requires a crossbite, nonanatomic posterior teeth are often used or cusp-fossae with the upper buccal cusps opposing the lower fossae.

Immediate denturesImmediate dentures


Many dentulous patients, especially those with severely worn dentitions, have a discrepancy between ICP (intercuspal position) and RCP (retruded cuspal position ie centric jaw relation).

Removal of the natural teeth will permit and encourage a retrusive shift in mandibular posture. If so cusp fossae or monoplane posterior denture teeth should be used.

Immediate denturesImmediate dentures


A single denture opposing natural dentition will require cusp teeth. Since artificial teeth have their own morphology they do not occlude well against natural teeth unless the natural teeth are recontoured via enameloplasty to better receive the prosthetic teeth.

In the case of maxillary denture opposing mandibular natural teeth the most likely, practical occlusal scheme will use the mandibular buccal cusps as the functional cusps opposing the maxillary fossae

ChoicesChoicesLingualizedLingualized


ChoicesChoicesSemi-anatomicSemi-anatomic


ChoicesChoicesLingualized vs MonoplaneLingualized vs Monoplane


ChoicesChoicesMonoplaneMonoplane


ChoicesChoicesAnatomicAnatomic


Good Residual Ridges Well Coordinated

Patient Previously successful

with anatomic dentures Denture opposes

natural dentition When “Lingualized”

occlusion is desired

Poor Residual Ridges Poor Neuromuscular

control (Bruxers, CP etc.) Previously successful

with Monoplane Dentures or Severely worn occlusion on previous denture

Arch discrepancies– Class II or III or Cross-bite

Immediate Dentures– except when opposing

natural dentition Potential poor follow-up

Monoplane Occlusion Anatomic Denture TeethIndications for ApplicationIndications for Application

No vertical component to aid in shearing during mastication

Occlusal adjustment impairs efficiency unless spillways and cutting edges restored

Patients may complain of lack of positive intercuspation position

Somewhat esthetically limited (don’t look like natural teeth)

Reduction of horizontal forces

CR can be developed as an area instead of a point

Freedom of movement Can develop solid

occlusion despite arch alignment discrepancies

Easily adapted to situations prone to denture base shifting

Easy to set and adjust teeth

Advantages DisadvantagesMonoplane OcclusionMonoplane Occlusion

Difficult to set Less adaptable to arch

relation discrepancies Horizontal force

development due to cusp inclinations

Harmonious balanced occlusion is lost with denture base settling

Requires frequent follow-up and may require more frequent relines to maintain proper occlusion

Definite point of positive intercuspation may be developed

Esthetically similar to natural dentition

Tooth-to-tooth and cusp-to-cusp balanced occlusion can be achieved

Maintains some shearing ability after moderate wear

Advantages DisadvantagesAnatomic OcclusionAnatomic Occlusion

Good esthetics Freedom of non-

anatomic teeth Potential for bilateral

balance Centralizes vertical

forces Minimizes tipping forces Facilitates bolus

penetration (mortar and pestle effect)

High esthetic demands Severe mandibular ridge

atrophy Displaceable supporting

tissues Malocclusion Previous successful

denture with Lingualized Occlusion

Indications for use AdvantagesLingualized OcclusionLingualized Occlusion

22.criteria for posterior tooth selection

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