14. Resin-bonded Fixed Dental Prostheses Flashcards
Resin-Retained Fixed FDPs
v It consists of one or more pontics supported by thin ____ retainers placed lingually and proximally on the abutment teeth.
v It relies on ____ bonding between etched enamel and metal casting.
v It is based on the concept of v____ Dentistry
metal
adhesive
minimum invasive
Cast Perforated Resin Retained FDPs.
v Rochette in 1973 introduced this technique.
v Wing like retainers with funnel shaped perforations to provide ____.
v The restorations were bonded with heavily filled composite resin as luting medium.
v Problems
ØWeakening of the retainer by ____.
Ø____ to wear of the resin at the perforation.
ØLimited ____.
mechanical retention
perforation
exposure
adhesion
Etched Cast Resin Retained FDPs (“Maryland Bridge”)
v Thompson and Livaditis at the university of Maryland developed a technique for electrolytic etching of Ni-Cr and Cr-Co alloys.
v Advantages include:
____ is improved because the resin-to-etched metal bond is much stronger
Ø The oral surface of the cast retainer is highly ____ and resists plaque accumulation.
Ø Micromechanical bonding into the undercuts in the metal casting created by ____.
retention
polished
etching
Macroscopic Mechanical Retention (“Virginia Bridge”)
vWas developed at the Virginia University, School of Dentistry.
vIt involves a “lost salt Crystals” technique by incorporating salt crystals into the retainer patterns to produce roughness on the inner surfaces. (____ Mechanical Retention)
vThis technique permits the use of any ____.
macroscopic
metal ceramic alloys
Chemical Bonding Resin Retained FDPs (Adhesion Bridges)
v Development of adhesive systems for ____ adhesion to metal.
v It is based on the addition and modification of the cement with adhesion promoter ____, a halogenated Phosphate group in its structure, allows for better ____ to metal
v ____ has shown excellent bonds to air abraded Ni-Cr and Cr-Co alloys as well as tin plated gold and gold palladium -based alloys.
direct
4-META
adhesion
panavia
PREPARATION OF THE METAL SURFACES
Electrochemical pit corroding technique using a 3.5% solution of nitric acid, and utilizing an electric current for 5 minutes, followed by immersion in 18% Hydrochloric acid for 10 minutes -> It’s not always successful though
Later the surfaces were coated with pylorized ____ which improved the retention
In adhesion bridges, sandblasting with ____ is considered just as effective as all the other method
silane
aluminum oxide
THE ROCATEC SYSTEM
The most recent method of abrading the inner surface of the metal retainer resulted in the deposit of ____ on this surface.
With the subsequent addition of ____, this facilitated the bonding procedure
silica
silane
THE ROCATEC SYSTEM
Sand blasting with110 um Aluminium Oxide with a force of 280 megapascals at a terrific speed
This is followed by a chemical procedure with a further blast of sand mixed with ____.
The impact energy resulting from this process allows the silicon particles to actually ____ with the roughness in the metal This improves the ____ of the cement to the bridge
silicon dioxide
fuse
adhesion
Patient Assessment, Diagnosis, and Treatment Planning
l Before providing the patient with a resin bond retained prosthesis, careful and thorough assessment is important.
l This assessment should include: ____
vExamination ____ vDiagnostic casts
history
radiographs
ØThe occlusion with the opposing arch should allow sufficient space for the prosthesis after tooth preparation.
ØLoss of space through drifting may pose a problem in pontic construction
ØThe possible presence of
____ habits and ____ should be evaluated
parafunction
dietary habits
Patient Assessment, Diagnosis, and Treatment Planning
ØThe alveolar ridge in the pontic area should have a firm healthy ____.
ØThe extent of tooth preparation should be evaluated in relation to the path of ____ of the prosthesis and presence of undercuts
mucoperiosteum
insertion
ØActive periodontal disease and caries may ____ the construction of a prosthesis.
ØThe need for crown ____ should be considered.
ØAbutments should be tested for vitality, and ____ taken to assess root length and periodontal support.
contraindicate
lengthening
radiographs
Advantages
- minimal tooth prep, minimal disturbance to pulp
- supragingival margins
- minimal disturbance to periodontal tissue
- ____ quality of enamel maintained
- anesthesia not usually required
- easy impression making
- provisional not usually ____
- reduced chair time
- reduced patient expense
- rebonding is possible
protective
required
Disadvantages
- uncertain ____
- cannot be used in patients with a deep overbite
- where enamel is thin, ____ of the abutment teeth may occur
- they can not be used where heavily restored abutments are present
- they can not be used where the shape of abutments may require considerable alteration
- difficult temporization
- sensitivity to
longevity
graying
nickel
Indications
Replacement of a single missing tooth in a relatively ____ span in an otherwise ____ dentition
Intact den??on = mouth and teeth are healthy w/ no contraindica?on
short
intact
Splinting
Indications of periodontally ____ teeth
compromised
Indications
Replacement of ____ teeth where pulps of
abutment teeth are ____
missing
large
Indications
- as a ____ following orthodontic treatment
retainer
Indications
l Closure of median ____.
diastema
Contraindications
v Abutments are heavily ____ or ____ compromised
restored
endodontically
Contraindications
Where ____ is unfavorable.
In a patient who requires an ____ replacement in the presence of an unstable or nonexistent ____ occlusion.
occlusion
anterior
posterior
Contraindications
Compromised ____ structure, or if abutments have insufficient ____ for bonding
enamel
enamel
Contraindications
l Grossly ____ or rotated abutments.
l Presence of a ____
l Presence of a ____
tilted
diastema
long span
ESSENTIALS FOR SUCCESS
l 1. ____ Selection
Most ____ thing is to make sure it’s a good case for this
type of procedure. Don’t ask the sprinter to run a marathon.
l 2, ____ Design
l 3, Flawless ____ technique
case
important
preparation
clinical
OBJECTIVES OF OF PREPARATIONS FOR RESIN RETAINED FDPs
To include as much enamel as possible without impacting on :-
- THE ____
- THE ____
- THE ____
- ____ HEALTH
occlusion
esthetics
pulp
periodontal
Preparation
- in maxillary incisors reduction of the lingual mesial and distal marginal ____
- maxillary canines may require reduction of the ____ lingual ridge
ridges
central
PREPARATION
- in mandibular anterior teeth may require slight modification of the ____ aspect to provide an irregular surface
- only in incisor relationship needs reduction for interocclusal clearance
lingual class III
axial reduction
- the proximal walls should be prepared to achieve the planned optimal path of ____ and provide sufficient length, the margin terminating supragingivally at a point which still allows for the provision of a ____ embrasure space
insertion
cleanable
In selected cases, shallow ____
can be a useful addition to increase retention
grooves
Axial reduction
l The axial reduction should be extended ____ and lingually,
achieving an angle of taper of ____ degree, and involving ____ degrees around each abutment.
(____)
Remember this term!!
buccally
6-8
180
wrap around
l Margins should be well defined with a light ____ and supragingival so that the edge of the metal framework remains at least ____ mm from the soft tissue.
l To stabilize the restoration and insure that precise seating is accomplished ____are advised in anterior teeth.
chamfer
1
cingulum rests
ADDITIONAL RETENTION & RESISTANCE FORMS
1, Addition of ____ shaped occlusal Rests
2, Joining of the rests along the ____
3, The interproximal connectors should be at least ____mm high (These extensions increase the rigidity of the retainers)
4, Finish line should be a ____
spoon
central fossa
2
mild chamfer
CANTILEVER RBFDPs
There has been a lot of evidence lately that, in selected cases, retention is improved when using only ____ abutment instead of two….(92% to 74%)
The reason is that the variable pressures on each tooth, both in magnitude and direction, leads to abnormal stresses and strains which causes ____ of the prosthesis
one
debonding
SAYS HE STARTS GOING FAST FROM HERE ON OUT
Clinical phase I vTooth \_\_\_\_ v Impression vOcclusal \_\_\_\_ vTooth shade and pontic selection
modification
registration
Tooth modification
l The tooth modification required to develop the appropriate path of ____ should be predicted.
l A diagnostic ____ will help with pontic design.
insertion
mock-up
Tooth modification
l Careful assessment of the occlusal clearance both in the ____ position(red) and all ____(blue) should be performed prior to and during tooth modification procedures.
interocclusal
excursions
Impressions
l Working impressions are usually made using an ____ impression material.
l A satisfactory impression should be free of voids
and have clearly defined and recognizable margins.
elastomeric
Bite registration shade selection
l An interocclusal registration may be required if the ____ is difficult to locate on study casts.
l Tooth shade selection should be made in ____ and ____ lighting, and a prescription chart formulated
maximum intercuspation
artificial
natural
l The working cast may be poured using an improved ____ or a ____ material.
stone
refractory
Read slide
l The finished pattern should be checked for adequate ____ thickness, space for gingival extent of porcelain and proximal cleansability.
connector
l The pattern is invested using a standard technique and cast in ____ metal alloy.
l If a refractory cast technique is used the pattern is waxed and sprued and invested ____ with the cast.
non-precious
together
l The casting may be checked for shape and contour prior to the framework____
try-in
clinical phase II
- the metal framework should be checked prior to the addition of ____. to verify the acuuracy of casting and the extent of the margins the retention and stability of the framework
- the marginal fit, occlusal contact, embrasure sapces and connector position and thickness should be examined
porcelain
l Following porcelain application the metal framework should be rechecked
l Surface stains may be applied prior to ____.
glazing
If an adhesive system is used, the prosthesis should be cleaned in an ____ and ____.
ultrasonic cleaner
sandblasted
Bonding
l The abutment teeth are isolated using a ____.
lTeeth are polished using ____ and water, and then washed clean
rubber dam
pumice
ØEtch for ____ seconds with Panavia etching agent.
ØDispense one drop of each ED Primer liquid A and liquid B into a well of the mixing dish and mix until the desired consistency is attained
ØUsing a small applicator apply the mixture to the prepared tooth surface.
ØAfter ____ second evaporate with a gentle stream of air, the surface will appear ____.
15-30
60
glossy
v Apply the ____ to the internal surface of the casting and seat it.
v With a disposable ____ tip remove the excess cement.
v Apply oxyguard to the margins.
v After ____ minutes remove the oxyguard with a cotton roll and water spray.
v Remove the excess cement with an explorer.
cement
brush
3
The beauty of EMAX is that it is ~____ MPa flexural strength. Zirconia is ~____ MPa
Teeth undergo tremendous amounts of force.
It’s ~____ lbs/in^2 in males and ~____ lbs/in^2.
In the front it is ~____ lbs/in^2 in both male and female.
While the EMAX is much easier to bond, it isn’t as ____ as the zirconia.
400 1000 150 110 57 stronger
LITHIUM DISILICATE— IPS eMAX
-____ to bond,
Flexural strength only 400 MPAs More ____, thus more ____
ZIRCONIA
____ bonding procedure
Flexural strength up to ____ MPAs
easier
translucent
esthetic
complicated
1200
FAILURE OF RESIN BONDED FDPs
1, ____ !!!!
2, Fracture of Porcelain pontic
3, Fracture at the ____ site
debonding
connector
FAILURE OF A CONVENTIONAL FDP
1, Complete ____ of abutment tooth
2, Undetected ____ especially when you have full ____
3, 22% require ____ treatment
fracture
caries
coverage
endodontic
THE SURVIVAL RATE
1, ____ teeth do better than posteriors
2, ____. Teeth do better than Mand. Teeth
3, ____ abutment better than 2 abutments
4, 87% survival rate
anterior
max
one
Some Do’s and Don’t’s When Considering the Treatment Plan
Present all the options ____
Do not presume the patient could not ____ the costs involved
Do not offer any ____ expectations of success
There is an obligation to offer a ____
Only offer evidenced based assessments
available
afford
unrealistic
referral
3 UNIT CONVENTIONAL FPD
Disadvantages
1, ____ Preparations of virgin or minimally restored teeth
2, 20-25% chance of ultimate ____ treatment
3, Possible development of ____ in the abutment teeth
4, Overall ____ of the procedure
5, Difficulty of achieving a good ____ profile
6 Cost of remake 7, ____ visit
irreversible endodontic decay cost emergence multiple
3 UNIT CONVENTIONAL FPD ADVANTAGES
1, Esthetics
2, Capable of directing forces along the ____ axes of the abutments.
3, Longer survival rate, (Average of ____ years)
RBFDPs have only
been tested for ____ years
long
15
10
IMPLANT RETAINED CROWN
1, Involves invasive surgery with ensuing healing time.
2, Cost, multiple visits
3, Patient must meet several selection criteria
a) Inadvisable in certain ____ and pregnancies
b ) Availabilty of ____mm length and ____mm width of healthy bone
c) Must be positioned at least ____ mm from the Inferior dental canal,
____mm from periodontal ligament , and a safe distance from the adjacent teeth Must maintain a distance of ____mm from the mandibular foramen
diseases 10 0.5 1 3
