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A branch of prosthodontics concerned with the replacement or restoration of teeth or, both, by artificial substitutes that are not removable from the mouth.
1. Abutment
2. Retainer
3. Connector
4. Pontic
Dianne Stephanie M. Fadrigo
RETAINER
-It is the artificial crown that is cemented over the abutment tooth.
Pinlegde Retainer - is occasionally used
as a single restoration, generally to reestablish anterior guidance, in which case only the lingual surface is prepared.
USES:Retainer for FPDTo splint periodontally compromised tooth
Disadvantages:
1. Minimal tooth structure is lost.
2. Optimal periodontal response is achieved.
3. Optimal esthetic results can be attained.
1. Has less resistance to distortion.
2. It must be executed with greater than average skill and care.
3. Because of the first two factors, its application is rather limited.
Contraindications:For anterior teeth:1. The coronal tooth structure
is intact or nearly so.2. Normal coronal form is
present.3. The crown of the tooth has
average length r longer.4. The tooth has average or
greater labiolingual thickness in the incisal one-half of the crown.
5. The abutment teeth are in normal alignment or very nearly so.
1. When caries or a restoration extends past the normal outline of the preparation.
2. The crown of the tooth exhibits abnormal form or other developmental deffects.
3. The crown of the tooth is so thin labiolingually.
4. Conditions exist that could cause excessive torsional force to be applied to the retainer.
Pamela Rose Manaloto
It is a tooth, a portion of tooth, or that portion of dental implant that serves to support and/or retain a prosthesis.
1. Healthy/ Ideal Abutment2. Cantilever Abutments3. Pier Abutments4. Tilted Abutment5. Endodontically treated abutment
(depending on the amount of the remaining tooth structure)
6. Periodontically weak teeth7. Implant abutments
An unrestored vital tooth in its normal anatomic position is considered as an ideal abutment. This Ideal abutment should have all the features like ideal crown root ratio, adequate thickness of enamel and dentin, adequate bone support, absence of periodontal diseases and proper contour of the gingiva.
2. Cantilever Abutment
These are abutments present only on one side of the edentulous space capable of taking support.
3. Pier Abutments
It is a single tooth
with two edentulous
spaces on either
side. In this case the
single tooth will
have to act as an
abutment for both
the edentulous
spaces in the Dental
Bridge.
4. Tilted
Abutment
In this abutment,
either the design
of the prosthesis
should be
modified or the
tilt of the
abutment should
be corrected.
5. Endodontically treated
abutment (depending on the
amount of the remaining tooth
structure)
If a tooth is properly treated
endodontically, it can serve well as an
abutment with a post and core
foundation for retention and strength.
6. Periodontically weak teethThis abutment cannot take up
occlusal load as effectively as healthy abutment.
7. Implant abutmentsThis abutment is an implant and the
design of the prosthesis should be modified accordingly.
Dianne Mamaid
parts of a fixed partial denture (FPD) or splint that join the individual retainers and pontics together.
Usually this is accomplished with rigid connectors
RRigid Connector Cast Connector Soldered Connector Loop Connector
NNon Rigid Connector Precision type Non precision type
It can be made by casting, soldering, welding or Loop Connectors
Cast Connectors
shaped in wax as part of a multiunit wax pattern. Cast connectors are convenient and minimize the
number of steps involved in the laboratory fabrication
However, the fit of the individual retainers may be adversely affected because distortion more easily results when a multiunit wax pattern is removed from the die system.
Soldered connectors involves the use of an intermediate metal
alloy whose melting temperature is lower than that of the parent metal
Welding another method of rigidly joining metal parts.
Here the connection is created by melting adjacent surfaces with heat or pressure.
Loop Connectors Although they are
rarely used, loop connectors are sometimes required when an existing diastema is to be maintained in a planned fixed prosthesis.
Indications:when it is not possible to prepare two
abutments for an FPD with a common path of insertionIn case of grade 1 mobility, where reduction of force is
requiredWhen inlay is present or indicatedShort edentulous span
Precision Type involves a female part
(mortise) prepared within the contour of the retainer and a male part (tenon) attached to the pontic and fitting into the female part
Non-precision type could be in the form of
occlusal rest, subocclusal rest or lingual rest
Jennifer Katherine Su
An artificial tooth on fixed partial denture that replaces a missing natural tooth, restores its function, and usually fills the space previously occupied by the clinical crown.
Based on Mucosal Contact1. Saddle Pontic2. Ridge lap Pontic3. Modified ridge lap Pontic4.Ovate Pontic5. Bullet-shaped or conical or heart-shaped pontic6. Spheroidal and modified spheroidal pontic7. Sanitary or hygienic pontic8. Modified sanitary or perel pontic or arc-fixed
partial denture9. Articulated pontic
Based on Material1. Metal-ceramic Pontic2. Resin veneered Pontic3. All metal Pontic
Based on method of fabrication1. Custom-made pontic2. Pre-fabricated pontic
Based on Mucosal Contact1. Saddle PonticA pontic with a concave gingival surface that
overlaps the ridge buccally and ligually.The gingival surface will not have continuous
contact with the ridge instead only the buccal and lingual ends of the gingival surface will contact the tissue.
Major disadvantage: Difficulty in maintenance. Special instructions to floss (clean) the gingival surface should be given to the patient.
Generally avoided because they are very difficult to maintain and often leads to inflammation of the tissues in contact.
2. Ridge lap ponticThis pontic
resemble natural tooth.
It is designed to adapt closely to the ridge.
It is avoided because it is difficult to maintain and often leads to inflammation of the tissues in contact.
3. Modified ridge lap ponticRidge lap pontic evolved from
saddle pontic.Less tissue contact, but
difficult to maintain.Design with a slight
buccolingual concavity wherein food entrapment can occur.
Generally, this pontic is avoided because the buccolingual concavity is difficult to clean and maintain.
When the modified ridge lap is further reduced, they are known as lap facings.
4. Ovate PonticUsed in cases where the
residual ridge is defective or incompletely healed. Can also be used in broad and flat ridges.
Designed such that its cervical end extends into the defect of the edentulous ridge.
More aesthetic as it appears to arise from the ridge like a natural tooth. It is said to have evolved from root extended or root tipped pontics.
5. Bullet-shaped or conical or heart-shaped ponticHas a convex tissue surface, which contacts the
tissue at one single point without any pressure.This pontic is very easy to clean and maintain.Only disadvantage: poor aesthetics, due to wide
embrasures.
Indication: Replacement of mandibular posterior teeth where aesthetic is not a major concern.
6. Spheroidal and modified spheroidal ponticThese pontics contact the tissue only at the
ridge crest.They do not have concave gingival surfaces.They are indicated for cases with reduced
inter-arch space, where the pontic should give the appearance of an exaggerated occlusogingival dimension.
7. Sanitary or hygienic ponticsZero tissue contactEasy to maintainHighly unaestheticUsed only for posterior teethThe pontic should be at least 3 mm high
occluso-gingivally and at the same time provide adequate tissue clearance for easy maintenance.
.
Three common designs can be employed while fabricating a sanitary pontic They are:
a.) Bar sanitary ponticsHave a flat gingival surface that has sufficient
gingival clearance. b.) Conventional sanitary or fish belly
ponticThe gingival surface is convex both
buccolingually and mesiodistally.Disadvantages: The sizes of the connectors
are decreased, hence, the strength of the prosthesis is reduced and the mesial and distal contours of the pontic are difficult to maintain
c.) Modified sanitary or perel pontic or arc-fixed partial denture
The gingival surface is to design to be a hyperparaboloid. It is concave mesiodistally and convex buccolingually.
The arch shape increases the size of the connectors and is easier to maintain.
Bar sanitary pontic, Fish belly or conventional sanitary pontic and and Modified sanitary pontic
8. Articulated ponticsThere are modified pontics with inbuilt
connectors.The pontic is fabricated in two portions that
fit on to one another during insertion. Refer split pontic and cross pin-wing connectors.
Based on Material
1. Metal-ceramic Pontic
Advantages:AestheticBiocompatibleStraightforward procedureDisadvantages:Difficult to fabricate if the abutment is not metal
ceramic.Indications:Most situationsContraindications:Long span bridges.
2. Resin veneered Pontic
Advantages:Straightforward procedureConventional gold alloy substructure Disadvantages:Lesser strength compared to all metal ponticsPoor abrasion resistanceStaining at resin metal interfacePermeable to oral fluidsUnaestheticIndications:Long-term provisional restorationContraindications:Definitive restoration
3. All metal Pontic
Advantages:StrengthSingle step procedureDisadvantages:Permeable to oral fluidsPoor aestheticsIndications:Mandibular molars especially under high stressBruxismContraindications:Where aesthetic is more important
Based on method of fabrication
1. Custom-made ponticsMost commonly used type of pontics.Fabricate individually for the patient. A wax pattern is prepared and cast to prepare
the pontic.They offer superior aesthetics and flexibility
but the fabrication procedure is tedious compared to prefabricated pontics.
2. Pre-fabricated ponticThey are commercially available as porcelain
pontics.Should be adjusted according the individual
requirement.They are finally reglazed and fit to a metal
blacking (usually gold).
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