Midterm Flashcards
Tooth used to support prosthesis:
abutment
Residual bone & soft tissue covering that remains after tooth loss; part of support for certain types of RPDs
Residual (edentulous) ridge
RPD that depends entirely on natural teeth for support:
tooth-supported RPD
Also called extension based RPD:
Tooth-tissue supported RPD
RPD supported and retained by teeth at ONLY one end (also relies on tissue support)
Tooth-tissue supported RPD
In a tooth-tissue supported RPD, the denture base is supported by:
teeth and residual ridge
In a tooth-tissue supported RPD, discuss the goal of force distribution:
Least destructive forces are directed towards natural teeth (trying to preserve the remaining teeth)
Areas towards the posterior of the prosthesis are called:
distal extensions
Indications for RPD:
Edentulous area(s) are too:
long or numerous for a fixed prosthesis
Indications for RPD:
Need to restore lost _____, especially in the _____ region
soft & hard alveolar tissue; anterior
Indications for RPD:
Reduced ___ of remaining teeth
periodontal support
Indications for RPD:
Need to distribute ____ across the dental arch (= ______)
masticatory stresses; cross-arch stabilization
Indications for RPD:
No _____ tooth
posterior abutment
Indications for RPD:
Immediate:
replacement of teeth
Indications for RPD:
_____ & ____ of patient (____)
attitude and desires (economic desires)
Disadvantages of an RPD:
- Removable so not:
- May be:
- _____ may be visible, reducing ____
- May ____ during function
- May ___ while eating
- considered “part” of the patient
- lost or broken
- clasps; esthetics
- dislodge
- trap food
(T/F) A fixed prosthesis would be used over an RPD whenever it is not contra-indicated
true
Line encircling a tooth that designates its greatest diameter at a selection position determined by a dental surveryor:
height of contour/ survey line
How do you determine the height of contour of a tooth:
dental surveyor (survey line)
The height of contour will change if the ____ is changed
axial inclination
Portion of tooth ABOVE the height of contour:
Suprabulge areaT
T/F: The suprabuldge area is always concave towards the occlusal:
False: Its always CONVEX towards occlusal
Portion of tooth BELOW the height of contour:
Infrabulge area
The infrabulge area may also be referred to as the:
undercut
Surface of object below the height of contour in relation to the path of placement:
Undercut
What is the objective of prosthodontic treatment?
- Preservation of ______ not _____
- that which remains and not the meticulous replacement of that which has been lost
What is the objective of prosthodontic treatment?
- Eliminate:
- disease
What is the objective of prosthodontic treatment?
- _____, ___, and ____ of health of remaining teeth
- Preservation, restoration, and maintenance
What is the objective of prosthodontic treatment?
- _____ of lost teeth
- selected replacement
What is the objective of prosthodontic treatment?
- Restoration of ___ and ___ in ____ manner
- function & comfort; esthetically pleasing
- Why were the teeth lost?
- Does patient have caries or perio diagnosis?
- Has the patient has a previous unsuccessful RPD?
What part of the clinical examination do these questions relate to?
dental history
- diabetes- reduced healing potential
What part of the clinical examination does this relate to?
medical history
- Smoking
- Excessive sugar intake
What part of the clinical examination does this relate to?
Habits
In a clinical examination, in addition to the dental history, medical history, and habits, we also need to consider if the patients:
desires/expectations are reasonable or not
Fill in the remaining portions of the clinical examination:
- dental history
- medical history
- habits
- patient desires/expectations
- 6.
7.
- visual examination
- radiographic examination
- diagnostic casts
What are the 8 components to a visual examination?
- oral hygiene
- restorations
- caries
- periodontal assessment
- condition of soft tissue
- quality of residual ridge and hard tissue
- occlusion
- vertical space
Why is “oral hygiene a component” of the visual examination? (2)
- Good hygiene habits are necessary or decreased life of RPD
- The presence of an RPD can cause an increase in plaque
When completing the “restoration component” of the visual examination, what should we be looking for and why?
We should be looking at the condition of the existing restorations to determine if they need replaced prior to RPD (for adequate support of RPD)
When completing the “caries component” of the visual examination, what should we be looking for?
active disease
When completing the “periodontal assessment component” of the visual examination what five aspects are we looking for?
- probing depths in relation to CEJ
- attachment levels
- furcation involvement
- mucogingival problems
- tooth mobility
When assessing the periodontal component of the visual examination, if tooth mobility is noted, what also should be noted?
whether the mobility is biologic, iatrogenic or pathologic
- location of junction of residual ridge and unattached tissue (no flabby soft tissue)
- hypertrophied or hyperplastic tissue
- need for tissue surgery
- need for tissue conditioning
What component of the visual examination are these describing?
condition of soft tissue
- displaceable fibrous tissue
- tori
- exostoses & undercuts
- need for surgery?
What component of the visual examination are these evaluated in?
quality of residual ridge and hard tissue
- number of remaining teeth in occlusion
- tooth wear
- pathologic migration (medially-tipped teeth & intra-arch space issues)
- over-erupted teeth (inter0arch space issues- occlusal plane)
What component of the visual examination are these evaluated in?
occlusion
When examining inter-arch space issues (occlusal plane) we need a minimum of ___ space for material
4-5 mm
- Is there enough space for treatment to be successful?
- Thickness of materials: metal, denture base, teeth
- Excessively large non-resorbed ridges
- Over-erupted teeth
What component of the visual examination are these evaluated in?
Vertical space
What radiographs should be taken prior to fabricating an RPD?
- full mouth PAs
- Vertical bitewings
- Pano
It is important to correlate the radiographic examination with the:
visual examination
How do we evaluate prospective abutment teeth and what are we looking for?
Radiographically; root length, size and form
Tooth with ____ or ___ roots are more favorable for abutment teeth
large or long roots
What is the most important factor to evaluate when looking at prospective abutment teeth radiographically?
Crown-root ratio
When looking at the crown-root ratio we are looking at:
The length of the clinical crown & amount of root embedded in bone
What is a must for crown-root ratio of an abutment tooth?
Need atleast half of root embedded in bone
If the crown root ratio is greater than 1:1, this results in:
poor prognosis
What are the three types of RPD framework?
- Cast metal
- Acrylic
- Flexible base
What is an advantage to cast metal RPD framework?
better force distribution
What metals are commonly used for cast metal RPD framework? What is used most at UMKC?
CoCr (used most at UMKC) & NiCr (many ppl have Ni allergy)
What is the trade name for the flexible base RPD framework?
Valplast
What are the two types of clasp assemblies and where are they located on the tooth?
- Retentive- buccal/facial side
- Reciprocal- lingual side
Prevent the RPD from going toward the gingiva when patient bites down:
Clasp assemblies (retentive & reciprocal)
States that it is ideal for the clasp assembly to wrap around more tooth surface:
principle of encirclement
Prosthodontics replaces ____ & ___ and can replace the palate with ___
teeth & oral tissues; obturator
Reproduction for demonstration (no accuracy implied)
model
Accurate positive reproduction of arch:
cast
Encircles tooth that designates its greatest diameter:
height of contour/ survey line
The height of contour will change if:
axial inclination is changed
Area ABOVE the height of contour:
suprabulge
Area BELOW the height of contour
infrabulge
The retentive undercut is located within what area?
infrabulge
Only ____ contact the tooth below the survey line:
clasp tips
Only clasp tips contact the tooth:
below the survey line
Depends entirely on the natural teeth for support:
Tooth-supported RPD
What Kennedy class is associated with a tooth-supported RPD?
Class III
Extension-base RPD:
Tooth-tissue supported RPD
RPD supported and retained by teeth at only one end:
Tooth-tissue supported RPD
What Kennedy class is associated with a tooth-tissue supported RPD?
Class I or II
In a tooth-tissue supported RPD, the denture base is supported by:
teeth and residual ridge
When fabricating a tooth-tissue supported RPD, it is better to have forces distributed on ___ than on ___
Teeth; soft tissue
Edentulous area other than thought deterring the classification:
modification space
In applegates rules, no modifications exist in ____ arches (because this would make it a class ___)
Class IV; Class III
The objectives of removable partial dentures include (hint: 3 restores, provide, improve, splint)
- restore anatomical defect
- restore function
- restore occlusal plane
- provide posterior occlusal support
- improve esthetics
- splint periodontally compromised teeth
The metal framework of an RPD includes:
- major connector
- minor connector
- rest
- direct retainers
- indirect retainers
Joins units on opposite sides of the arch:
major connector
List 3 functions of the major connector:
- stress distribution (teeth & soft tissue)
- unification (partial denture acts as one unit)
- cross-arch stabilization (counterleverage)
What are the 4 types of maxillary major connectors?
- Palatal strap
- AP palatal strap
- Complete palate
- U-shaped (horseshoe) connector
What are the types of mandibular major connectors? (2)
- lingual bar
- lingual plate
A RIGID extension from major connector or base that contacts the proximal surface of abutment tooth:
proximal plate
The connecting link between major connector/base & other units (retainers & rests):
minor connector
Describe the 3 types of minor connectors:
- guiding planes/plates
- meshwork
- any unit connecting any type of rest to major connector
A component of the RPD that transfers the forces against the prosthesis down the long axis of the abutment tooth:
Rest
The rest should transfer the forces against the prosthesis down the _____ of the abutment tooth
long axis
Prepared surface of a tooth/restoration to receive the rest:
rest seat
Component of RPD used to retain & Prevent dislodgment:
direct retainers
Portion of the direct retainer in which two arms are joined by a body which may connect to a rest:
Direct retainer - clasp assembly
Stabilizes the RPD against displacing forces away away from tissue in pure rotation around the fulcrum:
Indirect retainer
Usually connects to the major connector & is some form of rest:
indirect retainer
In what case is an indirect retainer necessary??
ALWAYS necessary in class I or II situations
Where should an indirect retainer be located?
perpendicular to fulcrum line, as far away as possible
Vertically parallel surfaces of abutment teeth:
guiding planes
Guiding planes are ____ surfaces of ___ teeth
vertical parallel; abutment
Why must guiding planes be created on teeth?
because flat planes don’t exist
How do you determine guiding planes?
Tilting cast in anterior-posterior direction
Guide planes provide one:
path of placement/removal for RPD
Guide planes ensure ____ of RPD components
intended actions
Guide planes eliminate/decrease:
gross food traps
Guide planes increase the frictional component of:
the minor connectors
Lowers height of contour on proximal surfaces to allow better positioning of arms:
guide planes
When creating a guide plane, ______ should be reduced in size
large undercuts adjacent to proximal surface
When creating a guide plane, reduction can be accomplished by either ____ of the cast or ____ the enamel
alternating the tilt; selectively grinding
When altering the tilt of the cast to create a guide plane, cast tilt should not:
vary far from horizontal
Where does selective grinding most often occur when creating guide planes?
occlusal 1/3-1/2
Location of guide planes:
proximal surfaces of abutment teeth
Guide planes should be parallel to ____ if possible. (posterior molars will be tilted _____)
long axis of teeth; mesially
When creating guide planes its important to remembers that as length is increased:
retention is increased & resistance to rotation is increased
The width of the guide plane should be as wide as the:
widest portion of the occlusal rest
The width of the guide plane should be as wide as the widest portion of the occlusal rest:
___ buccal-lingual width of the tooth
____ distance between cusp tips
1/3 BL widths of tooth
1/2 distance between cusp tips
What should be the length of the guiding plane in tooth supported class III abutments?
3-4 mm
What should be the length of the guiding plane in tooth-tissue supported (class I or II) abutments (distal extension):
1.5-2 mm
Paralleling instrument used in RPD fabrication:
Dental surveyor
What is our brand of dental surveyor? what is another brand?
- Ney
- Jelenko
Components of a surveyor include: (6)
- cast holder- (with surveying table)
- surveying stand
- vertical support post
- horizontal arm
- analyzing arm
- mandrel for surveying tools
The surveying tools include: (4)
- analyzing rod
- carbon marker
- carbon sheath
- undergauges (0.01, 0.02. 0.03)
- survey diagnostic cast
- contour wax patterns
- contour ceramic & cast resotrations
- place attachments requiring parallelism
- survey master cast
These are all functions of:
dental surveyor
The objectives of the dental surveyor:
- Determines most:
acceptable path of insertion
The objectives of the dental surveyor:
- Identify ____ that can function as ____
proximal tooth surfaces; guiding planes
The objectives of the dental surveyor:
- Locate and measure areas of teeth that may be used for:
retention
The objectives of the dental surveyor:
- Determine if soft or bone areas of _____ (____) exist
interference; undercuts
The objectives of the dental surveyor:
- Determine most suitable path of insertion to satisfy:
esthetics
The objectives of the dental surveyor:
- ____ on abutment teeth
delineate height of contour
The objectives of the dental surveyor:
- Record cast position to selected path of insertion (____)
Tripod cast
The path of insertion is determined based on: (4)
- guiding planes
- retentive undercut
- interferences
- esthetics
The greater the # of guiding planes =
the more specific path of insertion
The final orientation of guiding planes is seldom >
(greater than) 10-15 degrees from horizontal
When determining the path of insertion, the mechanical retention is provided by:
clasp that engages retentive undercut
The clasp that engages the retentive undercut (providing mechanical retention) resists:
RPD dislodging forces
What is the location of the retentive undercut?
lies between survey line & gingival margin
The retentive undercut is located by what device?
surveyor
T/F A distal undercut is the preferred retentive undercut
FALSE: FACIAL undercut is preferred
The retentive undercut is ideally within ______, at least _____
gingival 1/3; 1mm from gingival margin
The illusion of undercut due to excessive cast tilt:
false undercut
A false undercut: (2)
- does not exist clinically
- makes for an awkward path of insertion
List some interferences that may be seen when determining the path of insertion: (6)
- lingually inclined mandibular teeth
- Buccally inclined maxillary teeth
- Bony tori
- Height of contour too high
- Clasp placement too high
- Tissue undercut area of bar clasp
How can we locate & eliminate the interferences?
- altering tilt of cast/changing path of insertion
- maintaining cast tilt, eliminating by surgery or recontouring teeth
For the best esthetics when determining path of insertion:
Alter _____ cast tilt to allow for natural alignment of anterior teeth
mediolateral
For the best esthetics when determining path of insertion:
If inadequate space for natural tooth width, recontour ____ to restore lost dimension
proximal surfaces
T/F: For esthetic purposes when determining the path of insertion, we should tilt the cast medial-distal to allow for alignment of anterior teeth:
FALSE- you should alter the cast tilt mediolaterally
You should avoid exaggerated cast tilt to the path of insertion because the patient is:
unable to open mouth sufficient to accommodate
When marking the height of contour/survey line, the side of the ____ indicates survey line of abutment teeth at chosen path of insertion
carbon marker
The tip of the carbon marker will show you the:
incorrect survey line
ALL components of RPD except ____, lie above the survey line
terminal 1/3 of retentive clasp
The survey line is ideally at:
junction of middle & gingival 1/3
The proximal 2/3 of retentive clasp and the entire reciprocal clasp is located:
In middle 1/3, above the survey line
If the survey line is too high (occlusally), the clasp is too high on the tooth and this may cause: (2)
- interference with occlusion
- increased leverage on the tooth
If the survey line is too high (occlusally), what should you do to the survey line?
recontour the tooth to lower survey line
If survey line is too low, no ____ exist
undercut
If the survey line is too high, the ____ is too high on the tooth
If the survey line is too low, no ___ exist
clasp; undercut
If the survey line is too low, no undercut exists meaning : (2)
- no clasp retention
- can’t use enameloplasy to change
If the survey line is too low, no undercuts exist. What does this require?
surveyed crown (basically you took too much tooth structure away and now the patient needs a crown)
How do you measure the retentive undercut?
measured with proper undercut gauge chosen at path of insertion
The amount of undercut varies depending on the:
clasp type
The amount of undercut varies on the clasp type.
CrCo= ____
Wrought wire= ____
CrCo= 0.010
Wrought wire= 0.02 or 0.03
Undercuts are marked with:
red pencil
How should you fix an inadequate undercut? (3)
- enameloplasty
- addition of composite
- surveyed crown
When tripodizing the cast, record tilt of cast at:
chosen path of insertion
Tripodizing the cast ensures:
The lab tech can re-establish the path of insertion
How do you tripodize the cast?
marker touches 3 widely separate tissue surface areas and vertical lines are drawn parallel to analyzing rod on these points
Color code for RPD:
- metal framework outline
- wrought wire clasp
blue
Color code for RPD:
- retentive undercut
- tooth modification areas
- guiding planes
- survey line reposition
- rest seat areas
Red
Color code for RPD:
- Survey line
- Tripod marks
- Soft tissue undercuts
Black
The impression for the master cast is done:
after mouth preparation
When resurveying the master cast: (4)
- align guiding planes
- mark retentive undercuts
- mark survey line
- tripoidize the cast
RPD survey & design steps: (4)
- Survey diagnostic cast
- RPD design
- Mouth preparations
- Master cast
The RIGID extension of FPD/RPD
Rest
Prevents cervical movement of the RPD:
Rest
If the rest does not prevent cervical movement of the RPD, this can cause damaged to:
underlying soft & hard tissues (initially a sore spot but can then lead to bone loss of the abutment tooth)
What limits lateral movement of the RPD?
Rest
Maintains the retentive arm in proper vertical relation:
rest
The rest maintains the retentive arm in proper vertical relation and by doing this it stabilizes ____ and prevents ____.
occlusal forces & prevents gingival dislodgment
What are the 5 functions of a rest:
- directs forces down the long axis of teeth
- prevents cervical movement of RPD
- limits lateral movement of RPD
- maintains retentive arm in proper vertical relation
- improves occlusal plane
- Prevents cervical movement of RPD
- Limits lateral movement of RPD
Rest
Portion of natural tooth/cast restoration prepared (for the rest)
rest seat
When preparing a rest seat, evaluate ___/____ relationships in both ___ & ___ movements
interocclusal/interincisal; static & excursive
Types of rests include: (5)
- occlusal
- embrasure
- cingulum/lingual
- hooded
- incisal
Rest located on the mesial/distal pits of PM and molars:
Occlusal
Occlusal rests should be centered over the ____ whenever possible
marginal ridge
What type of teeth are occlusal rest seats narrower on?
pre molars
Describe the shape of an occlusal rest seat:
concave; saucer/spoon shaped
The base of the occlusal rest seat should be ____ over the ____
triangular; marginal ridge
Occlusal rest seat measurements:
____ B/L width
____ width between cusp tips
1/3 B/L width; 1/2 width between cusp tips
In an occlusal rest seat, what is the reduction over the marginal ridge? what is the reduction in the deepest area?
1.0-1.5 mm
1.5-2.0 mm
The floor of an occlusal rest seat should incline towards ____ , forming angle less than
axial center; 90 degrees
If a tooth is tilted, an occlusal rest seat can be ____ to ensure maximum bracing which redirects forces along the long axis of the abutment tooth
extended
What type of rest is on 2 adjacent posterior teeth?
embrasure
The form of an embrasure rest follows the form of:
an occlusal rest
In an embrasure rest, you should avoid eliminating:
the contact point
The “sluiceway” of an embrasure rest should be around _____ (____)
2mm wide; within embrasure
A “sluiceway” of an embrasure rest allows for:
1mm thickness of metal on each tooth
How wide should a “sluiceway” of an embrasure rest be? How deep should it be?
2mm wide; 1 mm deep
An embrasure rest should have a ___ shaped trough to accommodate clasp assembly
U-shaped
What type of rest should be prepared on canines with a gradual lingual slope? (maxillary canines specifically)
cingulum/lingual
Although cingulum/lingual rests should be prepared on canines (specifically maxillary canines) with a gradual lingual slope, they can be prepared on:
any anterior tooth in cast restoration
For a maxillary cingulum/lingual rest, how do you accomplish?
For a mandibular cingulum/rest, how d you accomplish?
cut into enamel
use composite resin
How wide should the floor be in a cingulum/lingual rest? Where should it extend?
1mm wide; marginal ridge to marginal ridge
From an incisal view, a cingulum/lingual rest is what shape?
crescent shaped with widest point at center
From a lingual view, a cingulum/lingual rest is what shape?
Inverted V
Rests on inclined surfaces displaces teeth and destroys bone which is why we use a ____ rest.
cingulum
A hooded rest is ONLY used for:
mandibular 1st premolar
A hooded rest decreases ____ by lowering ____
torque; lowering center of rotation
A hooded rest is ONLY used for mandibular 1s PM and only in Kennedy class:
I or II
Where does a hooded rest extend from? What is it part of?
extends from marginal ridge to marginal ridge; part of lingual plate
The least desirable type of rest:
incisal
Why is an incisal rest the least desirable? (3)
- poor esthetics
- occlusal interference
- increased torquing forces
When discussing rests, do we want the torque to be increased or decreased?
decreased
Incisal rests (the least desirable rests) are used primarily on:
mandibular caninines
Incisal rests are usually used as:
indirect retainer
Describe the shape of an incisal rest:
small, V-shaped notch
What types of rests are most commonly used?
- occlusal
- embrasure
- cingulum
What is the MINIMUM reduction for rest seat preparation?
1 mm
A 1 mm minimum reduction for rest seat preparation allows for:
adequate thickness of metal
If the rest seat preparation is not at least 1 mm this is considered inadequate thickness which may result in:
rest fracture
What phase of patient treatment is being described?
- Relieve pain & infection
- Diagnostic cast & mounting
- Tx plan- design RPD
- Educate & motivate patient
- Occlusal equilibration
Phase 1
What phase of patient treatment is being described?
- Remove deep caries & temporary restorations (disease control)
- Extract non-retainable teeth
- Preprosthetic surgery (tori reduction etc.)
- Periodontal treatment & plaque control
- Interi proshtesis- functional & esthetic
- Occlusal equilibration
Phase 2
What phase of patient treatment is being described?
- Definitive endo tx
- Definitive restorative tx- surveyed crowns, amalgams, composite, FPD
- Occlusal plane correction
- Enameloplasty for RPD
Phase 3
What phase of patient treatment does “enameloplasty for RPD” occur in?
Phase 3
What is involved in both phase 1 & 2 of patient treatment?
Occlusal equilibration
In what phase of patient treatment does construction of the RPD occur in?
Phase 4
What phase of patient treatment is being described?
- Post-insertion care
- Periodic recall
- Continued plaque control (hygiene!!!)
Phase 5
Preliminary design of RPD with tooth modification areas marked:
diagnostic casts
- Perform tooth modifications according to RPD design
- Use QA worksheet
These steps are involved in:
mouth preparation
Steps of enameloplasty (5):
- Develop guiding planes
- Enlarge embrasure for minor connectors
- Lower height of contour
- Create undercut if needed
- Prepare rest seats
When developing guide planes during an enameloplasty:
The proximal guide plane should be adjacent to:
edentulous area
When developing guide planes during an enameloplasty:
ML contains:
Lingual contains:
stress release clasps; reciprocal clasps
During an enameloplasty, you should _____ for minor connectors
enlarge embrasure
When lowering the height of control in an enameloplasty, what components are involved?
- proximal 2/3 circumferential retentive clasp
- reciprocal clasp
- lingual guide plate
After doing the enameloplasty, you should:
make additional impression & survey interim casts to confirm that the preps are parallel to the path of insertion
If there is an insufficient undercut, what surface should be sloped when performing the enameloplasty?
buccal
When creating an undercut during an enameloplasty, what bur should be used?
round-end tapered diamond bur
What is another name for lingual rest seat?
chevron
What types of rest seats are most common?
Occlusal & lingual
When preparing rest seats, you need at least ___ of space, and this can be measured with ____
1mm; beading wax
Kennedy Class _____ & ____ : residual ridge not providing RPD support (tissue supported)
III & IV
In what Kennedy classes is the residual ridge IMPORTANT source of RPD support (tooth-tissue supported)?
Kennedy Class I & II
In what Kennedy classification is it more important to accurately record maximum tissue support areas (broad-stress distribution concept):
Kennedy Class I & II
In what Kennedy classification is the occlusal pressure concentrated on the distal end of the base?
Kennedy Class I & II
In an extension RPD impression, equalize support from:
tissue & teeth
In an extension RPD impression, a ___ should be used with elastomeric material that is ____
custom tray; border molded
What type of impress is most commonly used?
1 step impression
What impression technique is considered “very complicated”?
Corrected/Altered cast technique- 2 step impression (alternate technique)
The major connector can be described as:
RIGID
The major connector should function as:
1 unit
- Broad stress distribution
- Counter- arch stabilization
- Reduce torque
- Avoid tissue damage
These are all functions of:
major connector
The major connector should not enter______ and should avoid terminating on _____.
Should not enter undercut areas; free gingival margin, lingual frenum & movable soft palate
Maxillary major connector borders should be ____ to & _____ from the gingival margins
parallel to & 6mm
For a maxillary major connector, the anterior and posterior borders should:
cross midline at right angle
Maxillary major connector borders beaded ____ wide & deep
1mm
What are the types of suprabulge clasps?
- circumferential
- akers
- circlet
What are the type of infrabulge bar clasps?
- T
- 1/2 T
- I-bar
What type of infrabulge bar clasps are most common?
1/2 T and I-bar
What are the advantages of bar clasps?
- more esthetic
- more flexible
- less conductive caries
- wider range of undercut adaptability (I-bar)