Edentulous Mandible - Fixed Prostheses

5. Edentulous Mandible
Fixed Prostheses

John Beumer III DDS, MS
Hiroaki Okabe CDT
Division of Advanced Prosthodontics, Biomaterials and Hospital
Dentistry, UCLA
This program of instruction is protected by copyright ©. No portion of this
program of instruction may be reproduced, recorded or transferred by any
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information storage or retrieval system, without prior permission.

Fixed vs Removable
Edentulous mandible

Patient selection and treatment planning based upon:
! Biomechanics
! Esthetic challenges
! Psychological demands
! Need for hygiene access
!   Oralcompliance
!   Quality of the soft tissues

! Cost

Implant Supported Fixed Prosthesis - Mandible
Implant Biomechanics –
Minimum requirements

Length of implants
!  Minimum length – 7 mm
Number of implants
!  Minimum number - 4
Anterior - Posterior (A-P)
Spread
!  Minimum amount – 1 cm

Implant Supported Prosthesis - Mandible
Minimum requirements
! Length of implants
!  Minimum length - 7 mm
! Number of implants
!  Minimum number - 4
! A-P Spread
! Minimum amount – 1 cm

Biomechanics and A-P spread

!  Only 4 implants have
placed but the Anterior –
Posterior spread is10 mm
and is sufficient for a fixed
prosthesis with cantilever
extensions of up to 20 mm.

Unnecessary implants were placed in this patient

!  Implants are unnecessary posterior to the mental foramen in
almost all patients unless the foramen are located so
anteriorly that an appropriate A-P spread cannot be
established.

!  If a fixed prosthesis is fabricated for this patients, it must be
made in segments and designed to allow for flexure of the
mandible during function.

Fixed Implant Supported Prosthesis -
Mandible
Anterior – Posterior Spread
A-P Spread
(1 cm or more)

Cantilever
Length

Cantilever length should not exceed 2 times
the A-P spread or a maximum of 20 mm.

Implant Supported Prosthesis - Mandible
"

Insufficient A-P spread combined with excessive
cantilever length

Result
!  Mechanical failures
!  Implant overload

In this patient the result
was recurrent fractures
of the prosthesis
retaining screws
(arrows).

Implant Supported Prosthesis - Complications
Insufficient A-P spread combined with excessive cantilever length
(34 mm on the left side and 26 mm on the right side)
Result:
! Mechanical failure - Implant fracture
! Implant overload

In this patient a combination of excessive cantilever length and
insufficient A-P spread lead to implant overload and a resorptive
remodeling response of the adjacent bone and implant fracture.

Implant Overload and Bone Resorption
Possible Mechanisms of Implant Failure*
!  Excessive occlusal loads
!  Resulting microdamage
(fractures, cracks, and
delaminations [arrows])
!  Resorption remodeling
response of bone is provoked
!  Increased porosity of bone in
the interface zone secondary to
remodeling
!  Vicious cycle of continued
loading, more microdamage,
more porosity until failure
(Howshaw et al, 1995; Brunski et al, 2000; )

Even though six implants have have been placed, A-P spread
is only about 5 mm. The cantilever extension must be limited to
10 mm and this is insufficient to restore the posterior dentition
with a fixed prosthesis.

A-P Spread


A-P Spread

In this example the A-P spread exceeds 10 mm. This is quite
sufficient to restore the posterior dentition with a fixed prosthesis.


The A-P spread and the
cantilever lengths were within
the prescribed limits in this
patient. When these limits are
observed the success rates of
implants supporting these
restorations exceeds 95% and
the mechanical failures are few.

Fixed vs Removable
Edentulous mandible

Patient selection and treatment planning also
based upon:
!  Esthetic challenges
! Psychological demands
! Need for hygiene access
!   Oralcompliance
!   Quality of the soft tissues

! Cost

Fixed vs Removable
Esthetics
Some older patients, because of lack of muscle tonus,
require the presence of a properly contoured denture
flange in order to establish proper contours of the
lower lip and the corner of the mouth particularly
during a high smile.

Fixed vs Removable
Esthetics
Note the poor contour of the lower lip and corners
of the mouth in this patient who was fitted with a
fixed hybrid prosthesis.

Fixed vs Removable
Need for hygiene access when the implants
emerge through poor quality mucosa

Such tissues are more difficult to maintain in a healthy condition
and when implants emerge through poorly keratinized unattached
mucosa removable overlay dentures are recommended because
oral hygiene access is easier for the patient.

Fixed vs Removable
Amount of Keratinized Attached Mucosa

!   Both these patients have little or no attached keratinized
mucosa
!   Because of a lack of keratinized attached mucosa these
patients would be best served with removable overlay
dentures.
!   Oral hygiene procedures are much easier to perform when the
implants are surrounded by keratinized attached mucosa.

Fixed vs Removable

!  Thispatient presented with ample residual keratinized
attached mucosa. Note that almost all of these
implants have well formed gingival cuffs. If the patient
is capable and willing to properly use the hygiene aids,
fixed would be a suitable choice for this patient.

Fixed vs Removable

!  The labial surfaces of these implants emerge through
poorly keratinized unattached mucosa. The patient
is elderly and has difficulty manipulating oral hygiene
aids. Removable overlay dentures were therefore
recommended.

Fixed vs Removable
Oral Compliance

!  It is difficult to manipulate the hygiene aids used in patients
with fixed edentulous bridges. If the patient has impaired vision
or impaired motor skills, removable overdentures are
recommended because of facilitated hygiene access.

Fixed vs Removable
Oral Hygiene

One week post delivery

!  Oral hygiene must be maintained meticulously. Otherwise
chronic peri-implant gingival infections develop which can
result in considerable morbidity.

!  Peri-implantitis is already beginning to develop on the patient
on the right one week post delivery. Fixed was probably the
wrong choice for this patient.

Infection an hypertrophy of peri-
implant tissues

Secondary to a combination of:
!  Plaque
!  Poor quality peri-implant tissues

Implants in the Edentulous Mandible
Common Problems
! Severe resorption
! Buccal-lingual dimension most important. Less than 5-6 mm requires
bone augmentation

! Lack of attached keratinized tissue
! Hygiene compromised when the implants are surrounded by poorly
keratinized unattached mucosa
! Palatal grafts are favored over skin grafts

! Lack of interocclusal space
! Limits design choices
! Compromises prosthodontic procedures
! Commonly encountered when a patient still retains residual dentition in
either the maxilla or mandible
! Seen in some recently edentulated patients

Severe Resorption
Anatomic Limitations
Severely resorbed mandibular body
a)Vertical height – less than 7 mm
b)Buccal lingual dimension - less
than 7 mm at the implant sites

Mandibles that are smaller than the above are at risk for fracture
during or immediately after implant placement and should be
augmented with a bone graft.

Severe Resorption
Anatomic Limitations

!  The mandible fractured through the right posterior implant site
two weeks following implant placement.
!  Reconstruction with a bone graft prior to implant placement
would have been a better choice for this patient.

Severe Resorption

Mandibles that are smaller than the above
are at risk for fracture during or immediately
after implant placement and should be
augmented with a bone graft.

Courtesy Dr. H Davis

Lack of Keratinized Attached Tissue
"  Partial thickness flaps with apical repositioning
"  Palatal grafts are preferred over skin grafts

Soft Tissue Surgical Procedures
Free palatal Grafts
! Donor tissue is sized to recipient-site dimensions
! A thick split-thickness graft approaching full
thickness is preferred (1.25-1.75 mm) when
abutment coverage is desired
! Primary contraction is negligible with palatal
grafts
! Secondary contraction is rarely a problem

Courtesy Dr. M. El Ghareeb

Free palatal graft harvest:
Donor site 4 weeks after surgery

! A uniform graft is harvested with sharp dissection
! Hemostasis is achieved with electrocautery
! The donor site is dressed with absorbable collagen
! A palatal stent or a soft lined maxillary complete
denture is provided to protect site & improve patient
comfort.

Free palatal graft
Atrophic MN with thin Creation of a uniform periosteal
band of attached ST
recipient site

Immobilization of graft One week postoperative:
at recipient site Superficial epithelial
sloughing & initial revascularization

Lack of interocclusal space
!  Recently edentulated patients
!  Patients to be fitted with an immediate denture followed by an implant
supported fixed edentulous bridge
!  Patients with supereruption of anterior teeth prior to extraction

Note the supereruption of the
mandibular teeth.

When these teeth are removed an aggressive alveolectomy
needs to be performed prior to placement of implants.

Interocclusal space
Minimum amount -15 mm from the head of the implant to the
plane of occlusion in order to design an appliance with both
hygiene access and sufficient strength and rigidity to withstand
the rigors of mastication.

15 mm

Interocclusal space
!  Thereshould be sufficient space between the
bottom of the bridge and the gingival tissues for
proxy brush access between the implants.

Interocclusal space
Insufficient hygiene access

There is insufficient space for proper hygiene
access. The risk of peri-implantitis and tissue
hypertrophy will be substantial in this patient.

Ensuring proper
implant position and angulation
Surgical templates
Existing dentures, if
they are of
appropriate contour
and tooth position,
can be duplicated to
make effective
surgical templates.

Role of Trial dentures

!  Trialdentures are made when the teeth of
existing dentures are improperly positioned.

Proper implant Position and Angulation

! Implants should be positioned so their screw
access channels exit through the cingulum region
of the anterior teeth.

! They should be angled so they are perpendicular
to the plane of occlusion. Why ?

!  Linguallyinclined implants existing through the
tissues of the floor of the mouth are unusable and
must be buried. Why?
!  Theconstant movement of the floor of mouth tissues
around the implants leads to uncontrollable tissue irritation

!  Labiallyinclined implants are a significant problem
for the prosthodontist and lab technician. Why?
!  Theyrequire the fabrication of custom substructures
adding significant complexity and cost to the prosthesis.

at the Time of Second Stage Surgery
Partial thickness flap with apical repositioning:
!  Can be utilized to increase
Narrow zone
zone of attached tissue with of keratinized
mucosa
limitations secondary to
contracture
!  Apical repositioned flaps are
sutured to the periosteum Sharp
supra-periosteal
(arrows) dissection
!  A soft lined CD is provided to
protect site, improve patient
comfort & minimize relapse Partial thickness flap
Is apically repositioned
& sutured to periosteum


Tissue Management

!  Whether a one stage or two stage surgical procedure is used
closure should be designed to surround the implants with
keratinized attached tissue.
!  Peri-implant tissues must be thinned as necessary in order to
minimize peri-implant pocket depths.

Healing Period
!  The denture surfaces overlying the surgical sites are
aggressively relieved
!  A temporary denture reliner is used to reline the
denture in this area

Fixed Implant Prostheses
Treatment Choices

!  Two types
!  PFM Fixed

!  Fixed hybrid prosthesis

Fixed Prosthesis Options
Porcelain fused to metal prosthesis
Advantages
! Excellent esthetics
! Nonporous materials
! Little or no wear of occlusal surfaces

Disadvantages
! Expensive to fabricate
! Time consuming
! Requires a high level of technical expertise
! Prone to cracks and fractures which are difficult and time consuming
to repair.

Fixed hybrid prosthesis

Components
!   Cast metal framework
!   Acrylic resin
!   Denture teeth

Advantages
! Less costly
! Easier technically to fabricate
! Easier to maintain and repair

Disadvantages
! The acrylic resin retaining the denture teeth is porous
and will absorb bacteria and odors
! Wear of the denture teeth
! Wear and deterioration of the pink acrylic resin

PFM vs Fixed Hybrid Prosthesis
We prefer the fixed hybrid prosthesis
!  Less costly
!  Easier to fabricate
!  Easier to maintain and repair

Fixed Hybrid Prosthesis PFM prosthesis

Impressions
Two techniques
!  Use a pickup type impression copings with
linked copings and a master impression tray
!  Use transfer type copings with a stock tray
and a silicone impression material

Master Impressions using transfer type (closed
tray) impression copings with a stock tray
!  Transfer type impression copings have been
secured to the implant fixtures. A variety of shapes
are available.

! A stock tray designed to make impressions for partially
edentulous patients, (shown above), can be used to make this
type impression. Note that in the anterior region of the tray is
developed to accommodate the height of the impression copings.


! Before placing the impression copings into position they
should be carefully inspected. If imperfections are discovered
they should not be used for master impressions.
! Be careful not to entrap tissue between the coping and the
implant fixture.
! A polysiloxane impression material with sufficient rigidity
must be used


!  The impression is removed and inspected. The retromolar pad must be
recorded in the impression.
!  The transfer type impression copings are removed from the patient and
attached to implant fixture analogues.
!  The impression coping – fixture analogue units are then placed into the
impression as shown above.
!  The impression is boxed as shown previously and poured with improved
dental stone using the manufacturer s specifications regarding water
powder ratios

Making the master cast

!  A separating medium is applied to the silicone impression to
prevent the Gingitech from adhering to the impression
material.
!  The joint between the fixture analogue and the Impression
coping is covered completely with the Gingitech material.
!  The impression is then boxed and poured with improved
dental stone.

Master Impressions - Linked copings technique
using pick-up (open tray) impression copings
Transfer impression
Stock tray Preliminary Impressions are coping
made with transfer type
(closed tray) impression
copings and a stock tray

The healing abutments are removed and
replaced with transfer type impression copings


Transfer impression copings
are connected to implant
fixture analogues and placed
into the impression

! Beforeuse carefully inspect the undersurface of the
impression copings (arrow). If any imperfections are
noted they should not be discarded

Impression copings are secured to the fixture analogues
imbedded in the preliminary cast with long guide pins


! Pick–up type (closed tray) impression copings are screwed
onto the analogues embedded in the cast
! Dental floss is used to connect the impression copings
! Auto polymerizing acrylic resin is used to connect the
copings


! The copings are separated from on another with a thin
separating disc
! The impression copings are blocked out wax
! The impression tray is made. Note that the tray extends to
record the retromolar pad for this area must be recorded
in the impression


! Impression copings are connected
together with either cyanoacrylate
or a pattern resin. In this patient
cyanoacrylate was used.


! In this patient pattern resin was used to
connect the impression copings

Pick-u

! The master impression tray is tried in to insure it
seats easily and in the proper manner. The guide
pins should project through the top of the tray.
Sometimes the holes for the guide pins need to be
enlarged
! The impression is made with an elastic impression
material

using pick-up (closed tray) impression copings
Pick-u

! Note that the retromolar pad is recorded in the impression. Why?
! The retromolar pad is one of the anatomic land marks used to determine
the proper plane of occlusion

! The connected impression copings are embedded as one unit
ensuring that they will accurately record the position and
angulation of the implants in the master cast.


! 

! Boxing the master impression. The land of the cast should be
4-6 mm wide.
! The impression is boxed as shown previously and poured with
improved dental stone using the manufacturer s
specifications regarding water powder ratios

Master cast with fixture analogues imbedded

! Note that the retromolar pads (ovals) were recorded in the
impression. These are important landmarks in determining the
plane of occlusion.
! The land of the cast should be at least 4 mm wide. This will
later be used to retain a silicone template.

Record Bases

The cast undercuts and those
around the healing abutments,
are blocked out with wax,
separating medium is applied and
the record base completed with
tray resin.

Facebow transfer record

!  Afacebow transfer record is made and the
upper master cast transferred articulator.

Facebow transfer record

!  Remove the facebow from the patient. Insert the maxillary
cast into the record on the bite fork and attach the cast and
face bow to the articulator with the jig.

Design of Record Bases

!  Record bases should cover the retromolar pad.
!  The labial flange should be shorted in order to
more truly represent the contours of the final
prosthesis.

Centric Relation Records
!  VDO
and centric relation records are
made in a customary fashion

Centric Relation Records

!  Mount the lower cast with
the centric relation record

Occlusion
If opposed by complete denture
! Bilateral balanced occlusion

If opposed by implant assisted
overlay denture

If opposed by implant supported
prosthesis
! Group function (Mutually protected
occlusion) or
! Anterior guidance

If opposed by natural dentition
occlusion) or

Trial Denture

! 

! 
! 

!  Refine anterior esthetics

Fabricating the Metal Framework
A silicone template is made using a silicone putty

Labial-buccal silicone matrix technique
The anterior teeth are removed from the record base
and attached to the silicone template. A small amount
of sticky wax will help connect the denture teeth to the
template.

Labial-buccal silicone matrix
!  The
matrix is designed to be removed in
segments while developing the contours of
the metal framework.

Metal framework design and fabrication

Basic design guidelines – Metal framework
1.  Cantilever extension should not
exceed two times A-P spread
or 20 mm

2.  When possible the screw
access holes should be through
metal

3.  Narrow labial lingual thickness
anteriorly

4. Proxy brush access between
implants

5.  The cantilever extension should be
designed to minimize food impaction .

6. Metal – acrylic resin finish line on the
lingual side of the distal implants
should be 4-6 mm in height.

7. In cross section, the undersurface of
all portions of the framework must be
convex.

8. Provide sufficient retention for acrylic
resin.


Why ?
Implant overload and bone loss
Mechanical failures

Implant Supported Prosthesis - Complications
Insufficient A-P spread combined with excessive cantilever length
(34 mm on the left side and 26 mm on the right side)
Result:
! Mechanical failure - Implant fracture
! Implant overload

In these patients a combination of excessive cantilever length and insufficient
A-P spread lead to implant overload and a resorptive remodeling response of
the adjacent bone and implant fracture and implant failure.

Cantilever length
!  Not
to exceed two times A-P spread to a maximum of 20
mm.

2. When possible the screw access
holes should be through metal. Why ?

When screw access channels are in acrylic resin, the resin
tends to craze and crack over time, resulting in loosening of
teeth, facilitating microleakage and eventual detachment of
the resin from the metal framework.

3. Narrow the labial lingual thickness anteriorly. Why ?

To facilitate
hygiene access.


4. Proxy brush access between implants.
Why ?

To facilitate oral hygiene access to the prosthesis
between the implants and the undersurface of the
prosthesis.

5.  The cantilever extension should be of one of two designs:
!  4 mm above the alveolar ridge. (original Branemark design)
!  In contact with the posterior alveolar ridge with proxy brush access
just posterior to the distal implant.

.

6. Metal – acrylic resin finish line on the lingual side
of the distal implants should be 4-6 mm in height.

Fracture of the metal framework
Insufficient vertical height of metal on the lingual
side led to fracture of the cantilever extension
2years after delivery.

7. In cross section, the undersurface of all
portions of the framework must be convex. Why ?

To enable proper hygiene access. Concavities on the under
side of the prosthesis are difficult to clean. Dental plague will
accumulate in these areas which leads to tissue irritation and
hypertrophy.

8. Provide sufficient retention for acrylic resin. Why ?

To prevent separation of the acrylic resin from the metal
framework. Loop and struts are preferred to bead
retention.

Separation of acrylic resin from the
metal framework

! 

!

Prevention of Microleakage between the
metal framework and the acrylic resin

! 
!


Summary
!  No concave under surfaces
!  Screw access holes in metal when possible
!  Proxy brush access
!  Retention for acrylic resin
!  High lingual finish line for strength and rigidity
!  Limit cantilever to 2 times A-P spread but no
more than 20 mm.
!  Cantilever extension 3-4 mm above the tissue

Cast Frameworks
!  Wax pattern
!  Burnout
!  Cast and finish
!  Section/Solder if necessary

Metals used:
! Gold palladium
! Silver palladium
! Type III gold

Verifying the fit of the metal framework
!  If transmucosal abutments are used fit can be checked visually
!  If the framework is designed to engage the implant fixtures, fit is
determined by touch and feel.
!  X-rays can also be used but they must be taken a right angles
to the long axis of the implant

Finishing the prosthesis

!  The denture teeth are attached to the metal framework
and the occlusion refined depending upon the status
of the opposing arch.
!  Since the opposing arch has been restored with a
fixed implant supported prosthesis, the occlusion will
be group function.

Occlusion
(Based on weakest arch)
If opposed by complete denture

If opposed by implant assisted
overlay denture

If opposed by implant supported
prosthesis
occlusion) or

If opposed by natural dentition
occlusion) or

Final Try In Appointment
The occlusion is fine tuned and the trial prostheses
are tried in one last time. During this appointment:
!  Verifyrecords
!  Obtain final esthetic approval from the patient

Preparing for flasking
!  Screw access holes that exit the posterior dentition should
be prepared so as to minimize the destruction of the
occlusal surfaces.

!

Flasking
!  Attach
fixture analogues to the bottom of the metal
framework

Flasking
!  Theprosthesis has been flasked. In one side is
the metal framework and in the other are
imbedded the denture teeth.

Flasking
The framework is removed from the cast, a metal
bonding agent is applied followed by a layer of opaque.

Finishing the prosthesis
Following processing of the heat cure acrylic resin
the prosthesis is carefully finished and polished.

Clinical remount and equilibration

In this patient the maxilla was restored with an
implant assisted overdenture. Therefore the
occlusal scheme was bilateral balance.

Delivery

Completed prosthesis
! Secured with gold alloy screws
! Note hygiene access
! Occlusion
! Anterior guidance with centric
only contact posteriorly
! Refined with a clinical remount

CAD – CAM Frameworks
!  The pattern is developed in the usual way
!  A laser scans the shape of the plastic pattern
into a computer.

Courtesy Dr. S. Lewis Courtesy Dr. S. Lewis

!  With all the data collected,
the milling procedure is
performed in one solid block
of titanium.

Courtesy Dr. S. Lewis


Completed framework. Note the design criteria are the
same.

Courtesy Dr. S. Lewis Courtesy Dr. S. Lewis

Titanium vs Zirconium Frameworks
Zirconium Frameworks
! Not recommended because
the blocks from which they are
milled exhibit flaws and as a
result these frameworks are
more prone to fracture.

Titanium Frameworks
!  Strong
!  Precise
!  Light-weight

!  Beware of metal frameworks designed by
the implant companies.
!  It is the responsibility of the restorative
dentist to design the metal framework

Angulation Issues
Labially inclined implants
Solution: Custom substructures with the prosthesis
retained with lingual set screws

Custom substructures are milled to a 3 degree taper.

Angulation Issues
Custom substructures with the prosthesis retained
with lingual set screws

Metal Substructure engaged
via lingual set screws

Fabrication of the metal framework

! Pattern resin is flowed over the customized
substructures and shaped appropriately.
! Note the development of the screw access
channels for the lingual set screws


Full contour wax pattern with denture teeth
Note: Proxy brush access


Full contour wax pattern with denture teeth
Note: Lingual set screws used to retain
the prosthesis

Denture teeth are removed and the wax pattern is cut
back creating sufficient space for the acrylic resin.
Note:
! Hygiene access
! Lingual set screws for retaining the prosthesis

Custom substructures with the prosthesis

Finished metal framework
! It should fit precisely onto the
custom substructures
! It is retained by lingual set screws
as shown

Completing the prosthesis
! The denture teeth are attached
to the metal framework with wax
with the help of the silicone
template.
! The occlusion is then
reestablished.

Completed Prosthesis

Labially Inclined Implants
Custom substructures with the prosthesis

Custom substructures are screwed to the implant
fixtures with gold alloy abutment screws.

Labially Inclined Implants

Fixed hybrid prosthesis is
secured to the custom
substructures with lingual
set screws.

Angulation Issues
Custom substructures with lingual set screws

Completed prosthesis
! Note hygiene access
! Occlusion
! Anterior guidance with centric only contact posteriorly
! Refined with a clinical remount

Angulation Issues

!  Another patient with labially
inclined implants.
!  Silicone matrix made of the
denture set up.
!  The substructure is contoured
to be compatible with the
position of the denture teeth.

Angulation Issues

!  Completed custom substructure
!  Note that the patient s class III
jaw relation combined with
slight labial implant angulation
required the fabrication of the
customized substructure.

Angulation Issues

!  Metal framework is secured to custom substructure with
lingual set screws

Angulation Issues

!  Completed restoration

Fabrication of PFM Fixed Prostheses
for the Edentulous Mandible


!  Complete and verify trial denture
setup
!  Secure UCLA abutments with
resin cylinders to the fixture
analogues and connect them
together with pattern resin


!  Make silicone matrix of the
denture setup
!  Secure silicone matrix to
the master cast and flow
wax into the matrix


!  Refine wax pattern
!  Refine the occlusion
!  Note the hygiene
access

Basic contours – PFM Fixed edentulous bridge
!  Reduced labial lingual dimension for easy hygiene access on the lingual
side.
!  Limit cantilever to 2 times A-P spread but no more than 20 mm.
!  High lingual finish line of metal for strength and rigidity
!  Cantilever extension 3-4 mm above the tissue
!  Screw access holes in metal when possible
!  Proxy brush access for hygiene
!  No concave under surfaces


!  Cut back of wax pattern prior to casting

One piece casting fits the master cast perfectly.
Note the contours of the undersurface and the
buccal lingual dimension.


The fit of the casting is
verified intra-orally.
Method:
! Feel
! X-rays at right angles


Occlusal surfaces – Metal or porcelain:
!  Dependent upon the opposing occlusion

Completed maxillary prosthesis

!  Opposing
arch is restored with an
overdenture with resin denture teeth.

Completed Prostheses

Occlusal surfaces
Porcelain because the
prosthesis is opposing a
complete denture with
resin denture teeth


! 

! 

!


! The prosthesis was remade and
the metal framework strengthened
to prevent flexure
! Opposing arch was natural
dentition so metal surfaces were
used.

Edentulous Mandible - Fixed Prostheses

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