PDI Flashcards
Dentistry uses many classification systems
* Despite challenges (not always applicable, agreement not always present…)
* Examples
(3)
- ASA
- Kennedy’s classification of edentulous space and Applegate’s rules
- Other disciplines have classification systems
Dentistry uses many classification systems
Main Advantage:
- Comprehensive evaluation and Assessment of all necessary parameters to help in
Diagnosis, Treatment, and Prognosis
skiipped
Prosthodontic Diagnostic Index (PDI)
Evidence Based Dentistry
(3)
- 3 published articles, J Prosthodont, official publication of the American College
of Prosthodontists - Glossary of Prosthodontic Terms ed 9
- Rosenstiel S “Contemporary Fixed Prosthodontics” textbook, Elsevier ed
Prosthodontic Diagnostic Index (PDI)
Potential benefits of the system include:
(7)
(1) improved intraoperator consistency
(2) improved professional communication
(3) insurance reimbursement commensurate with complexity of care
(4) an improved screening tool for dental school admission clinics
(5) standardized criteria for outcomes assessment and research
(6) enhanced diagnostic consistency and
(7) a simplified aid in the decision-making process associated with referral
Prosthodontic Diagnostic Index (PDI)
* 3 classifications:
edentulous, partially edentulous, dentate
Four (4) categories in each classification:
class I - class IV
* Class I: an uncomplicated clinical situation
Class IV: represents a complex clinical situation
Classification System for Complete Edentulism
Diagnostic Criteria
(4)
- Bone Height (mandibular)
- Residual Ridge Morphology (maxilla)
- Muscle Attachments (mandibular)
- Maxillomandibular Relation
Class I
Class II
Class III
Class IV
Ideal or minimally
compromised
Moderately
compromised
Substantially
compromised
Severely compromised
Modifiers for all classifications: Increase Complexity
and Classification Level
(7)
- Esthetic concerns / challenges
- Presence of TMD symptoms
- Oral manifestations of systemic disease
- Psychosocial factors
- Maxillofacial defects
- Ataxia
- Refractory Patient
Class I: Partial Edentulism
1. Location and extent of edentulous area: ideal or minimally compromised
edentulous area confined to a single arch and may include:
(3)
- anterior maxillary span that does not exceed 2 incisors,
- anterior mandibular span that does not exceed 4 missing incisors,or
- posterior span that does not exceed 2 premolars or 1 premolar and 1 molar
Class I: Partial Edentulism
2. Abutment Condition:
ideal or minimally compromised
no need for pre-prosthetic therapy
Class I: Partial Edentulism
3. Occlusion:
ideal or minimally compromised
no need for pre-prosthetic therapy
Class I molar and jaw relationships.
Class I: Partial Edentulism
4. Residual Ridge Morphology:
Class I Complete Edentulism description
Biomechanical Considerations for Partial Fixed
Dental Prosthesis (FDP)
(4)
- Number of abutment teeth and number of missing teeth (simple vs complex)
- Splinted or pier abutment
- Non-parallel abutments
- Combined anterior and posterior FDP
Class I Partial Edentulism
(3)
- Ideal or minimally compromised edentulous area, abutment condition,
and occlusion - There is a single edentulous area in 1 sextant.
- The residual ridge is considered type A.
Most common FDP to replace more than two teeth with success
mandibular anterior FDP (replacing 4 incisors)
mandibular anterior FDP (replacing 4 incisors)
mandible vs maxilla prognosis
- Mandibular – better prognosis than maxillary
- Direction of forces inward toward arch
mandibular anterior FDP (replacing 4 incisors)
Replacement of missing canine
(2)
- Adjacent premolar and lateral incisor are weakest potential abutments
- Maxillary replacement – forces outside inter-abutment axis & directed outward
Class II: Partial Edentulism
Location and extent of the edentulous area: moderately compromised
Location: both arches have edentulous spaces and 1 of the following:
(4)
- anterior maxillary span that does not exceed 2 incisors
- anterior mandibular span that does not exceed 4 missing incisors
- posterior span that does not exceed 2 premolars or 1 premolar and 1 molar
- Any missing canine (maxillary or mandibular)
Class II: Partial Edentulism
Abutment Condition: moderately compromised
*Insufficient tooth structure to retain or support intracoronal or extracoronal restorations – — sextants
*Abutments in — sextants require localized adjunctive therapy (minor)
1 or 2
1 or 2
Class II: Partial Edentulism
Occlusion: moderately compromised
(2)
*Occlusion requires localized adjunctive therapy (enameloplasty – prematurities)
*Class I molar and jaw relationships are seen.
Class II: Partial Edentulism
Residual Ridge Morphology:
Class II Complete Edentulism description
Replacement of missing canine
(3)
- Adjacent premolar and lateral incisor are weakest potential abutments
- Maxillary replacement – forces outside inter-abutment axis & directed outward
- Best restored with implant-supported single crown
Restoration of the occlusal plane
(2)
*Occlusal interferences produced when FDP made to over-erupted
opposing dentition.
*Opposing tooth restored to correct occlusal plane
*Opposing tooth restored to correct occlusal plane
(2)
- May require RCT; periodontal surgery; orthodontics; extraction
- Prevents occlusal interferences in restored dentition
Tilted molar abutments
(3)
- Generally poor abutments
- Mesial wall must be over-reduced / overtapered (↓ resistance)
- Distal adjacent tooth may intrude on the path of insertion
- Distal adjacent tooth may intrude on the path of insertion
(2)
- Mesial surface may need re-contouring or restoration or extraction
- Consider orthodontic uprighting (3rd molar extraction)
Molar uprighting
(3)
- Places abutment in better position for preparation
- Distributes forces under loading through long axis of tooth
(helps prevent/eliminate mesial bony defects) - Enables replacement of optimum occlusion
Tilter molar abutments: non-rigid attachment
(3)
- Allows slight movement - short span
- Keyway in distal of premolar to avoid intrusion of molar (mesial seating action)
- Must prepare box in distal of premolar preparation
- (To accommodate the female / keyway)
Non-Rigid Connectors - Indications:
(4)
- Pier Abutment FPD
- Long span FPD with multiple abutments
- Non-parallel abutments – Tipped molar
- Planning for failure
Replacement / Restoration of Anterior Teeth:
Anterior Guidance
(2)
- The custom incisal guide provides a record of the incisal guidance that has
been established with provisional restorations or a diagnostic wax-up. - The custom incisal guide table provides a record for the lab to create the
desired anterior guidance in the produced prostheses
Class III Partial Edentulism
Location and extent of the edentulous area: substantially compromised
*1 or both arches; compromised support of abutment teeth
*Posterior maxillary or mandibular edentulous area — teeth
*Any edentulous areas including anterior and posterior areas of — teeth
> 3 teeth or 2 molars
3 or more
Class III Partial Edentulism
Abutment Condition: substantially compromised / fair prognosis
*Insufficient tooth structure to retain or support intracoronal or extracoronal
restorations – – sextants
*More substantial localized adjunctive therapy (perio, endo, ortho treatments) – – sextants
3
3
Class III Partial Edentulism
Occlusion: substantially compromised
(2)
*Entire occlusion must be re-established, but without any change in the occlusal
vertical dimension.
*Class II molar and jaw relationships are present
Class III Partial Edentulism
Residual Ridge Morphology:
Class III Complete Edentulism
Class 3 partially edentulous patients (2)
- Any edentulous areas including anterior and
posterior areas of 3 or more teeth - Maxillary canine and 2 contiguous teeth
Class III Partially Edentulous
* Edentulous area(s) are located in …
* The abutment condition is substantially compromised due to the need for …
* The occlusion is substantially compromised because …
both arches and multiple locations within each arch.
extracoronal
restorations. There are teeth that are extruded and malpositioned.
re-establishment of the occlusal
scheme is needed without a change in the occlusal vertical dimension
Class IV: Partial Edentulism
Location and extent of the edentulous area: severely compromised
(1)
*Any edentulous area or combination of edentulous areas requiring a high
level of patient compliance.
Class IV: Partial Edentulism
Abutment Condition: severely compromised
*Abutments in — sextants have insufficient tooth structure to retain
or support intracoronal or extracoronal restorations.
*Abutments in — sextants require extensive adjunctive therapy (ie,
periodontal, endodontic, or orthodontic procedures).
*Abutments have — prognoses
4 or more
4 or more
guarded
Class IV: Partial Edentulism
Occlusion: severely compromised
(2)
*Entire occlusion must be reestablished, including changes in the occlusal
vertical dimension
*Class II division 2 and Class III molar and jaw relationships are seen
Class IV: Partial Edentulism
Residual Ridge Morphology:
Class IV Complete Edentulism
Classification System for the Completely Dentate Patient
Class I
Class II
Class III
Ideal or minimally
compromised
Moderately
compromised
Substantially
compromised
Severely compromised
Classification System for the Completely Dentate Patient
Diagnostic Criteria
(2)
- Tooth Condition
- Occlusal Scheme
Class I: Dentate patient
Tooth Condition and Occlusal Scheme
* Ideal or minimally compromised tooth condition
* No localized adjunctive therapy required
* Pathosis that affects the coronal morphology of —; — sextant
three or
less teeth
one
Class I: Dentate patient
Tooth Condition and Occlusal Scheme
* Ideal or minimally compromised occlusal scheme
(3)
- No pre-prosthetic therapy required
- Contiguous, intact dental arches
- Class I molar and jaw relationships
Class II: Dentate patient
Moderately compromised tooth condition
*Insufficient tooth structure to retain or support intracoronal or extracoronal
restorations – — sextant (pin-retained core / post-core)
*Pathosis that affects the coronal morphology of — teeth in a sextant
*Pathosis can be in — sextants and can be in opposing arches
*Teeth require localized adjunctive therapy, i.e., periodontal, endodontic or
orthodontic procedure for a single tooth or in a single sextant
one
4 or more
2
Class II: Dentate patient
Moderately compromised occlusal scheme
(4)
*Occlusal scheme requires localized adjunctive therapy
* Enameloplasty on premature occlusal contacts
*Anterior guidance is intact
*Class I molar and jaw relationships
Class II Dentate Pt
* 1 sextant exhibits – defective
restorations with an esthetic
component
* Additional variables of (2) increase the
complexity of diagnosi
3
gingival architecture and individual tooth
proportions
Class III: Completely Dentate Patient
Substantially Compromised Tooth Condition
* Insufficient tooth structure to retain or support intracoronal or extracoronal
restoration— – sextants
* Pathosis that affects the coronal morphology of — teeth in — sextants
* Pathosis can be in — sextants in the same arch and/or in opposing arches
* Teeth require more substantial localized adjunctive therapy, i.e., periodontal,
endodontic or orthodontic procedures for teeth in — sextants
2
4 or more
3 or more
3
2
Class III: Completely Dentate Patient
* Substantially Compromised Occlusal Scheme
(1)
- Occlusal scheme requires major therapy to maintain the entire occlusal
scheme without any change in the occlusal vertical dimension
Class IV: Completely Dentate Patient
Severely Compromised Tooth Condition
*Insufficient tooth structure to retain or support intracoronal or
extracoronal restorations – — sextants
*Pathosis affects coronal morphology of — teeth in all sextants
*Teeth in — sextants require extensive adjunctive therapy (perio,
endo, or ortho
3 or more
≥ 4
≥ 4
Class IV: Completely Dentate Patient
Severely Compromised Occlusal Scheme
(3)
*Occlusal scheme requires major therapy to re-establish the entire
occlusal scheme including any changes in the occlusal vertical
dimension
*Class II, Division 2 malocclusion
*Class III molar and jaw relationships
How to Use the PDI classification in the Clinic
Summary of the PDI Information and Worksheets can be found in
axiUm under “Links”
Classification needs to be established in axiUm under:
(2)
- Removable Prosthodontic Consults and
- Fixed Prosthodontic Consults
