prosthodontic management of maxillectomy/obturators part 2 final copy

Namitha AP
III rd MDS
DEPT. OF PROSTHODONTICS

Implant retained prosthesis
Implant sites
Clinical procedures
Tissue bar design
Definitive obturators for dentulous patients with total maxillectomy defects
Partial denture design
Swing lock design
Clinical procedues
Altered cast impression procedures
Double processing method
Definitive obturators for dentulous patients with partial maxillectoiny defects
Definitive obturators for patients with other acquired maxillary defects
Maxillectomy defects extending to the posterior pharyngeal wall
Maxillectomy and orbital exenteration defects
Rehabilitation for patients with large avulsive
defects of the maxilla
Evaluation of maxillary obturator prosthesis
Relining
Combined Surgical-Prosthetic Rehabilitation
Summary

Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related.
Acquired, and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.182
The forces of
atmospheric
pressure, alveolar
ridge pressure, and
adhesion / cohesion
are no longer
sufficient to keep the
prosthesis in position
Implants
Retention
Supportstability
Masticatory performance may be
restored to presurgical levels
speech and swallowing
should be more efficient
Easier adaptation
to the prosthesis
Retention is provided on the
unresected side
Improved
stability will
enhance
retention on
defect side
Well retained prosthesis
enables the patient’s tongue
to position the bolus on the
unresected side where
residual denture bearing
surfaces can provide support
during mastication.

The implant survival
rate for these 78
implants was 69.2%.
Clinical data 102 implants in 26
patients
20 patients with 83
implants
4 were buried and
1 in patient who
had not undergone
stage 2 surgery
78 implants
available for study
6 patients with 19
implants
Not available for
follow up
acquired maxillary defects
secondary to resection of palatal
and paranasal sinus tumors
died prior
to stage-
two
surgery or
developed
recurrence
of the
tumor
Beumer J, Marunick MT,
Esposito SJ. Maxillofacial
Rehabilitation: Surgical and
Prosthodontic Management of
Cancer-Related. Acquired, and
Congenital Defects of the Head
and Neck. ed 3Hanover Park, IL:
Quintessence Pub. 2011.PAGE
NO.182

Implant
survival rates
Irradiated patient-
63.6%(67.0% before
radiation and
50.0% after
radiation )
Non irradiated
patients – 82.6%
Exposed
threads
Anterior implants-
greater in
number(2.7 times )
Posterior implants-
lesser in number
mean
dose
of 50
Gy
failures
Early
6 months
following 2
stage surgery
Late
1 year or
more
failed to achieve
osseointegration
within
failed after being
subjected to
clinical function
for
Minimum-
1or 2
threads
Moderate -3-
4 threads
Severe –
more than 4
threads
Bone
loss
Beumer J, Marunick
MT, Esposito SJ.
Maxillofacial
Rehabilitation:
Surgical and
Prosthodontic
Management of
Cancer-Related.
Acquired, and
Congenital Defects of
the Head and Neck. ed
3Hanover Park, IL:
Quintessence Pub.
2011.PAGE NO.182

A high percentage of implants placed
in the anterior maxilla demonstrated
moderate to severe bone loss while
few of those under function in the
posterior maxilla or the maxillary
tuberosity demonstrated moderate to
severe bone loss.
in the maxillary tuberosity,
where the bone quality is
generally poorer, virtually all of
the implant failures were early,
or prior to functional loading.
However, once osseointegration
was achieved and the implants
were placed in function, bone
levels did not appear to
deteriorate over time

 Excessive occlusal loading and the
delivery of excessive lateral
torquing forces to the implants
may have been responsible for the
pattern of bone loss
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed
3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.183
In large defects or
where only
tuberosities remained
single implants with
O - ring attachments
were used
used almost entirely for
retention rather than to
provide support and/ or
stability
Nonaxial forces delivered to the implant were
minimized.
Enable the prosthesis to rotate in just about
any plane

 Bone around implants that are subjected
to excessive forces undergoes a resorption
remodelling response.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and
Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of
the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.183
Clustered implants in the
residual anterior maxillary
segment - Hader bar
extension located posteriorly
on the unresected side
did not accommodate the
multiple axes of rotation that
develop from bolus
manipulation, mastication ,
and other mandibular
movements
Chewing forces, particularly on
the unresected side, resulted in
significant magnification of the
load applied to the distal
implant because of the
cantilevering effect
Tissue bar attachment system

•most ideal location
•opposite the most retentive portion of the defect , located along the
posterolateral wall
•satisfactory volume and density of bone
RESIDUAL ANTERIOR MAXILLARY SEGMENT
•Considered only when the bone in the residual anterior maxilla is
insufficient.
•bone is not very dense
•initial implant stabilization is difficult ( high failure rates at stage-two
surgery)
MAXILLARY TUBEROSITY
The number of implants and their location are determined by the
nature of the defect and the available bony sites.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of

• longer and mesially inclined implants
PTERYGOID PLATES
• if at least 10 mm of bone is available beneath the maxillary sinus.
• If insufficient bone is present , the sinus membrane can be elevated
and an autogenous bone graft placed to augment the site
EDENTULOUS POSTERIOR ALVEOLAR PROCESS
(a and b) Sinus lift and graft
used to augment the
posterior alveolar
ridge after total
maxillectomy. (c)
Tissue bar attached to the
implants, (d )
Completed obturator.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial
Rehabilitation: Surgical and Prosthodontic Management of
Cancer-Related. Acquired, and Congenital Defects of the
Head and Neck. ed 3Hanover Park, IL: Quintessence Pub.
2011.PAGE NO.183,184

 Conventional implants have been used in the residual elements of
the zygoma on the defect side of total maxillectomy defects
 To minimize lateral torquing forces delivered to the implants,
magnets may be used
very difficult surgically
to create a zone of
immobile tissues
around the implants
implants will exit the
tissues high in the
defect, making oral
hygiene very difficult
for the patient
implants are generally
positioned parallel to
the plane of occlusion,
they cannot be
engaged aggressively.
Disadvantages
O ring
attachment
In defects
lined with a skin graft
with good posterolateral
undercuts, these
implants make only a
limited contribution to
retention.
2011.PAGE NO.184,185

 Zygomaticus implants - 20 to 30 mm long - employed successfully in patients with
large or total palatectomy defects.
 For rehabilitation of total palatectomy defects - 2 implants be placed in each
residual zygoma and that all 4 be splinted together with a tissue bar
Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects
of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE
NO.185

The
Benefits
55° optimizes
prosthetic versatility
Machined sections
for exposed soft
tissue and decreased
rotations
Narrow Apex
Available for smaller
patients and easier
placement

a 15mm threaded apex
and a coronal machined
surface that can be
exposed to soft tissue in
oncology resections.
a Narrow-Apex with a
smooth mid-section and
MSc threaded coronal
region.
This implant is especially
useful in patients with
smaller anatomies.
Zygex Implant offers
the same machined
area with a narrower
apex of 3.4mm.introduced by Southern
Implants in 2002 to
accommodate a higher
angle for the restorative
table to be in the arch
and not the palate
providing prosthetic
versatility More recently, Southern Implants expanded the
55° Zygomatic Implant range

Immediate placement upon tumor
resection
 Useful in edentulous patients
 Reserved for patients with localized
tumors
Patients scheduled to receive
postoperative radiation therapy ?
 dose enhancement effect at the bone
implant interface will compromise
the vitality of the bone anchoring the
implant
Irradiation of existing implants- Backscatter
Several months later and just after
delivery of the tissue bar, the
tissues on the labial surfaces of
theimplants dehisced and the bone
overlying the implants sequestrated
leading to loss of the implants.

• left buried beneath the mucosa for 2 to 3 months
Implant placement
• Careful thinning of mucoperiosteum will help in creating a
zone of keratinized, attached mucosa around the implants.
Implants are exposed at stage-two surgery
• 3-4 weeks allowed for healing
Healing abutments are attached
Prosthodontic procedures parallel
those used for conventional
implant patients
patient continues
to use the
existing
obturator
prosthesis
surgeon can
facilitate implant
maintenance
If the
implants
exit in
mobile,
unattached
tissues-
replace this
nonkeratiniz
ed tissue
with
keratinized
attached
tissues
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-
Related. Acquired, and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE
NO.184
Free palatal grafts
excellent source of
keratinized tissue.
oral hygiene is
facilitated with
the use of
chlorhexidine.

• It is usually desirable before the retention apparatus is designed.
Fabricate a trial denture
• Can commence when peri implant tissues are well healed
Fabrication of the definitive obturator prosthesis
• that engage the implant fixtures
• inspected, and screwed tightly into position
Selection of suitable impression copings
• defect portion of the tray is augmented with periphery wax
An edentulous stock tray is chosen
NO.185
After
application
of a suitable
tray
adhesive,
impression
is made with
irreversible
hydrocolloid
material

•After removing the impression, impression copings are removed, attached to fixture analogs
as required, and inserted into the impression
A preliminary cast is poured with dental stone
•pickup-type impression copings are secured to the cast.
•The impression tray is designed to record the position and angulation of the implants as well
as the residual normal tissues and the defect.
Resin tray for master impression fabricated
•pick up-type impression copings are secured tightly in position and an elastic impression
material is used to modify the impression
•When the impression material has polymerized, the screws securing the copings to the
implant fixture are loosened and the impression is removed.
•Fixture analogs are then attached to the impression copings imbedded in the impression and
the impression is boxed.
Bordermoulding and secondary impression
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired,
and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.185

Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects
of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.186
•Healing abutments of the same length and diameter as those used
in the patient are attached to the implant analogs and the record
base is fabricated with autopolymerizing acrylic resin.
•The record base should positively engage these healing abutments.
The master cast is prepared
•transferred to an articulator that will accept the large maxillary
cast.
Facebow transfer record is obtained
•opposing mandibular cast is mounted on the articulator
The centric relation record is secured
This technique will
maximize the
stability and
retention of the
record base used to
make
maxillomandibular
registrations.

•The anterior teeth are selected and arranged using established criteria.
•The posterior teeth are selected and arranged according to neutrocentric or lingualized
occlusal concepts.
Teeth arrangement
•The waxed trial dentures are tried in the mouth, and centric relation and the vertical
dimension of occlusion are verified.
•The anterior teeth are evaluated for acceptable speech and esthetics.
Try in
•The trial dentures are repositioned on the articulator, and a stone or silicone template, with
the maxillary teeth incorporated within it, is fabricated.
•This stone template is mounted on the lower member of the articulator and used to design
and prepare the wax pattern for the retentive apparatus
Preparation of wax patterns for the retentive apparatus

 Implants should not be the sole means of retention,
stability, and support for the prosthesis.
 unite the implants with a rigid , precision -fitted
tissue bar that has retentive elements attached.
 forces that are potentially most damaging to
implants will result from occlusal loading - should
be designed to direct most occlusal forces along the
long axis of the implants.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of
Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence
Pub. 2011.PAGE NO.184
Implants
Stability Retention
Residual denture-
bearing surfaces
and key areas of the
defect
Support
Numerous factors complicate the design of the bar and the
distribution of occlusal forces for total maxillectomy patients.

Purpose
 to compare and evaluate the effects
on different tissue bar-implant
substructures used in the
rehabilitation of a total maxillectomy
defect when subjected to known
occlusal forces
Photo elastic analysis
 Davis et al developed a photoelastic model
based on a human maxilla that had
undergone a total maxillectomy to the
midline.
 Photoelastic materials were used to
simulate the bone around the implants and
the bone along the medial and lateral
aspects of the defect.
Three implants were used on the non defect side to simulate a common clinical situation, and bar
designs were fabricated with a gold alloy, duplicating various clinical conditions.

Three implants
supporting a bar with
Hader clips placed
mesial to the anterior
implant and distal to
the posterior implant
Three implants supporting a bar with ERA
attachments placed mesial to the anterior
implant and distal to the posterior implant
Three implants supporting a bar
with O - ring attachments
placed between the implants
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic
Management of Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed
Bar with ERA
attachments
with or
without rests
The following designs were tested

• extend into the defect to transmit occlusal forces to the cast.
Acrylic resin obturator extension base was fabricated
• anterior and posterior to the implants.
Loading regions selected for testing
• a force of 12 lb could be applied in both the vertical and lateral directions at each location .
Each loading zone had a ramp
• A force of 90 g was applied to the acrylic resin extension base ( weight of the obturator )
The photoelastic cast was firmly fixed to the base of the stage of a straining frame.
Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub.
2011.PAGE NO.185
O ring bar design
Hader bar design
Circularly polarized light was used to illuminate the cast.

 Anterior loads caused higher and more concentrated stresses around the anterior and middle
implants than did posterior loads, because posterior loads are partially supported by the
residual edentulous denture-bearing surfaces.
 The addition of occlusal rests on the bars between the implants increased the stability of the
prostheses and alleviated the stresses around the posterior implant when a posterior force was
applied.
 The O-ring-type attachment resulted in more favorable stress distribution than either the bar -
clip or the bar-ERA design.
 However, the 0-ring designs were not as retentive as the other attachment systems tested .
Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of
Davis et al concluded that proper attachment selection and design of the bar are a
compromise between retention and the need for stress distribution and maintenance of
the bone around the implants.

Guidelines:
 With the use of a resilient
attachment such as the
ERA, which allows for a
vertical compression of the
prosthesis on application of
an occlusal load , the
addition of occlusal rests
improves the distribution of
stresses.
 More of the occlusal loads
are absorbed by the residual
denture- bearing surfaces
posteriorly, and these forces
are directed more
favourably along the long
axis of the implants.
 The concave rest, milled
into the occlusal surface of
the bar, is in the shape of a
half circle and is the only
part of the bar that is
engaged by the prosthesis
other than the attachments Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic
when a load is applied to point 1 , the
prosthesis will rotate around the new axis,
AB, which passes through the distal
occlusal rest.
Load 2-
fulcrum CD
Load 3-
Fulcrum
EF

ERA attachments are attached to each side of the bar
and occlusal rests ( arrows ) are created on top of the
bar.
Rests on the metal framework
control the axis of rotation, reduce
the wear on ERA attachments and
directs more of the occlusal forces
alon the long axis of the implants
The attachments allow
the prosthesis to be
compressed into the
bearing surfaces but
provide retention
when dislodging forces
are applied
The attachments on either side of the
bar should not serve as rotation
points, because the plastic
attachments housed in the prosthesis
will wear rapidly, rendering the
attachment ineffective
rigid denture base will contact the
cantilevered portion of the bar and
create excessive cantilevering
forces, predisposing the patient to
bone loss around the implants.

support is provided
posteriorly by the
residual denture-
bearing surfaces and
anteriorly by the
implants
If the entire anterior maxilla remains, the number of
implants, their distribution , and the design of retention bar
follow more conventional prosthodontic principles
The attachments
connected to the
distal portion of the
bar are resilient and
allow for
compression of the
distalextension area
of the prosthesis
into the denture-
bearing surfaces
without applying
excess torquing
forces to the
implants.
Beumer J, Marunick MT, Esposito SJ.
Maxillofacial Rehabilitation: Surgical and
Prosthodontic Management of Cancer-
Related. Acquired, and Congenital Defects
of the Head and Neck. ed 3Hanover Park,
IL: Quintessence Pub. 2011.PAGE NO.186
Beumer J, Marunick MT, Esposito
SJ. Maxillofacial Rehabilitation:
Surgical and Prosthodontic
Management of Cancer-Related.
Acquired, and Congenital Defects
of the Head and Neck. ed
3Hanover Park, IL: Quintessence

 prognosis improves with the availability of teeth to assist with the retention , support,
and stability of the RPD and obturator prosthesis.
LOCATION
OF THE
DEFECT
LENGTH OF
LEVER ARM
MOVEMENT
OF THE
PROSTHESIS
ARCH FORM
TEETH
PARTAL
DENTURE
DESIGN
Prosthodontic Management of Cancer-Related.
Acquired, and Congenital Defects of the Head
and Neck. ed 3Hanover Park, IL: Quintessence

LOCATION OF THE DEFECT LENGTH OF LEVER ARM
 Considerably longer lever arms are
encountered in patients with
intraoral surgical defects.
 It is not uncommon for the defect to
extend from the midline to the soft
palate area or to the pharyngeal wall
EXTENT OF THE
SURGICAL
RESECTION
ANTERIORLY
VARIABLE
POSTERIORLY
MOSTLY AND rarely
does a distal abutment
tooth remain following
surgery.
Kennedy Class II partial denture with an
extensive lever arm

 In most defects, if forceful mastication occurs on the defect
side, the prosthesis will be displaced significantly into the
defect and has the potential to expose abutment teeth to
damaging lateral torquing forces.
DEGREE OF
DISPLACEMENT OF
CLASS II PARTIAL
DENTURE
Quality of edentulous
ridge and palate
Ability of the
prosthodontist to
balance the support
available from both the
edentulous segment and
the remaining teeth
With resection of portions of the palate, the mucosal and bony
support are compromised or may be lacking completely
Defect must be employed to minimize the movement of the prosthesis
to reduce the stress on the abutment teeth
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and
Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE188

Beumer J, Marunick MT,
Esposito SJ. Maxillofacial
Rehabilitation: Surgical and
Prosthodontic Management of
Cancer-Related. Acquired, and
Congenital Defects of the Head
and Neck. ed 3Hanover Park,
IL: Quintessence Pub.
2011.PAGE NO.188
provide less palatal shelf area -
Support is compromised , which
may lead to significant rotation
and subsequent movement of the
prosthesis into the defect during
mastication
SQUARE/ OVOID
ARCH FORM
possess more palatal denture- bearing
surface perpendicular to occlusal stress.
more stable prosthesis during function
and indirect retention can be more
effectively employed
TAPERING
ARCH FORM

 Partial denture designs must anticipate
and accommodate the principal movements
of the prosthesis during function without
exerting pathologic stresses on the teeth.
 Maximum retention , stability, and support
should be obtained from the use of the
defect.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital
Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.188
There may be occasions
when partial denture
designs cannot be fabricated
without placing stress on
teeth
close attention should be
directed to the occlusion on
the defect side to minimize
occlusal forces

 The basic principles of partial denture design should be followed
 The diagnostic casts should be surveyed carefully for
location of undercuts, location and contour of
potential guide planes, and selection of the path of
insertion
 A compound path of insertion must be employed to
use the undercuts available in the defect adequately.
MAJOR CONNECTORS
- RIGID
OCCLUSAL RESTS –
DIRECT OCCLUSAL
FORCES ALONG THE
LONG AXIS OF THE
TEETH
GUIDING PLANES –
FACILITATE
STABILITY, BRACING,
RETENTION WITHIN
PHYSIOLOGIC LIMITS
Eg. If the lateral and posterior undercuts in the defect are to be engaged properly,
the prosthesis must be inserted first into the defect and then rotated up into
position on the teeth.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical
and Prosthodontic Management of Cancer-Related. Acquired, and Congenital
Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub.
2011.PAGE NO.188

 principal difference is in
bracing
 As the defect becomes larger
and less favorable and the
remaining dentition more
linear, more resistance to
displacement in the horizontal
plane must be provided.
 This can be accomplished by
plating the lingual surfaces of
the remaining dentition
Developing partial denture designs that do not compromise
the health of the abutment teeth and their supporting
structures represents a unique challenge
Compromised
support, stability
and retention on
the defect side
Lack of cross
arch stabilisation
in many
maxillary defects
Long lever arms
and resultant
increase in load
Multiple axes of
rotation
Increased impact
of the forces of
gravity in large
defects

Partial denture designs that lock onto remaining dentition.
Excellent
retention
Additional stress on
abutment teeth
Premature
teeth loss
Used when key
anterior abutment
teeth have severe
labial inclinations
and high heights of
contour and where
surveyed crowns and
conventional
retainers are not a
viable alternative.
Edentulous modification
spaces and /or
interproximal spacing on
the nondefect side
facilitate the placement of
the distal portion of the
gate.
NO.188
vestibule must be of
adequate depth for the
placement of the gate
without encroaching on
the free gingival
margins
well -
prepared
rest seats
retainers emerging from the
gate should be thin, well -
contoured I- bars of
maximum length that
engage the teeth in the
gingival third or at the
same level as the cingulum
rests.

 To minimize stress on the teeth during closure of the gate, the distal end of the
gate (whether hinge or latch) should be located 8 to 10 mm from the nearest
abutment tooth engaged by a retainer on the gate.
 The length of the gate should be kept to a minimum
NO.188

 Abutments adjacent to the defect require special consideration .
 A tooth closely adjacent to the anterior margin of the defect should have a positive
rest and retainer if adequate retention is to be achieved for the obturator
prosthesis.
 If this concept is not employed , the prosthesis will tend to rotate out of retentive
areas posteriorly
anterior
retainer
and rest
ensure
proper
orientation
of the
prosthesis.

 These abutments are subject to
greater vertical and lateral forces
and are more frequently lost than
are abutments in other positions
 placement of a positive rest on this
anterior tooth is critical to its long-
term prognosis positive cingulum rests – direct occlusal forces
along the long axis of the abutment, avoid
displacement of the framework, especially lingually
or toward the defect
Recontouring
cingulum areas
by fabricating a
three-quarter
crown
incorporating
the rest into a
porcelain-fused -
to- metal crown
and Prosthodontic Management of Cancer-Related. Acquired, and
Congenital Defects of the Head and Neck. ed 3Hanover Park, IL:
Quintessence Pub. 2011.PAGE NO.188,189
extension area
immediately adjacent to
this abutment, which is
basically the defect,
provides little support.
lever arms can become
exceedingly long,
amplifying the forces
delivered to the
abutment

 If incisors are adjacent to the defect, consideration should be given to splinting
them with porcelain-fused-to-metal restorations and incorporating cingulum rests

 Compromised bony support for the tooth
adjacent to the defect does not permit its
use as a partial denture abutment.
 next tooth or other adjacent teeth must
be used for this purpose.
some patients it may be advantageous to remove
this tooth and place an implant in the site
compromised abutment teeth can be
treated endodontically.
The crown is
amputated
and the root
will serve as
an
overdenture
abutment
Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of the
Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.189

 result of the differential between the
compressibility of the periodontal ligament
apparatus of the abutment teeth and the mucosa
covering the edentulous ridge.
 Because the oral mucosa is significantly more
compressible, a fulcrum line is created , even with
a well -adapted prosthesis.
 If the edentulous ridge and a portion of the bony
palate are replaced with a large maxillary defect,
the movement around this same fulcrum line will
be significantly greater and more variable and
must be considered in the design of the resection
partial denture.
multiple axes or fulcrum lines,
including the classic defined
fulcrum line related to the most
posterior occlusal rests

The fulcrum line for Class II maxillectomy patients is dynamic
It shifts or changes during mastication relative to the size and
configuration of the defect, the position of the bolus, and the
masticatory force employed to penetrate it .
patients with such a defect are instructed to masticate on the
dentate unresected side
consider only those axes that are generated when the bolus is
incised or when the bolus is placed in the posterior extension
area on the unresected side.
Position of occlusal
or cingulum rests
Size and
configuration of the
defect
Magnitude and
location of
masticatory forces
on the defect side of
the prosthesis
NO.190

 The configuration of the arch and the size of
the defect also influence the extent of
movement around the fulcrum line.
tapering arches - less palatal shelf
available for support, and the remaining
dentition is more likely to exhibit a linear
configuration
when occlusal forces are applied in the
posterior region on the defect side, the fulcrum
line will essentially be identical to the tooth
alignment
More movement
around fulcrum
line
Increased effectiveness of indirect
retainers
importance
of saving as
many teeth
and as much
of the
anterior
maxillary
segment as
possible on
the defect
side
2011.PAGE NO.190

More bracing is required for maxillectomy patients with linear tooth alignments.
Bulkier prosthesis is both heavier and less stable and will usually exhibit more
movement when subjected to the forces of mastication on the defect side.
Gravitational forces are also more of a concern because of the weight of the
prosthesis

 .
 Even under the best of circumstances, will always be significantly greater than that
exhibited by a similar Class II partial denture for a nonsurgical patient.
 If the contours of the defect cannot be used effectively to enhance stability and support of the
prosthesis, then the degree of movement will even more extensive.
 larger the defect the greater the potential for movement.
 The partial denture framework must be designed to anticipate these movements and be
physiologically adjusted to allow for these rotations
 Otherwise, the abutment teeth will be subject to damaging lateral torquing forces.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of the

 Extreme trismus - very frustrating experience for both the
partially edentulous patient and the clinician (influence
the design of the palatal major connector)
 Many maxillectomy patients receive both surgical and
radiation therapy some time during the treatment of their
disease.
 In recent times, chemoradiation has been employed.
 Patients subjected to these treatment modalities,
especially those treated with chemoradiation postsurgery,
can develop significant trismus.
It is not uncommon for patients to
have a maximum opening of 10 mm
or less between the incisors when the
resection extends to the midline and
incisors remain
Management of Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed 3Hanover
Park, IL: Quintessence Pub. 2011.PAGE NO.191

 If a dynamic bite opener is not effective the RPD
design will be compromised
 depth of the palate may influence the design of the
RPD, especially for patients with tapering arches.
 Clinically, tapering arches tend to exhibit greater
palatal depth than either square or ovoid arches.
 The prosthesis cannot be rotated out of the mouth
on the defect side because the width of the
obturator is usually greater than the distance from
the lip commissure to the remaining maxillary
central incisor
Depth of
palate
any
replacement
teeth or
partial
denture
components
on the
nondefect side
maximum opening distance
between the incisors
B+C > A prosthesis cannot
be inserted or
removed.

 An alternative is to record as much of the palatal surface, teeth, and defect as
possible with the master impression for the RPD framework.
 Many times a sufficient amount of palate and teeth will have been recorded to
accommodate an anterior strap palatal major connector ( not the major connector
of choice because of its flexibility, it may be the only viable alternative.)
 After the partial denture framework is fitted and physiologically relieved, the
defect is recorded with an altered cast impression.
 trismus will also limit the extension into the defect, especially along the lateral
wall.
 flexibility of the lateral cheek and skin graft will often permit the prosthesis to be
rotated out of the defect and the mouth with lateral displacement of the cheek.
 patient should be warned that leakage will be a possibility because of the limited
extensions into the defect, especially along the posteromedial margin.
and Prosthodontic Management of Cancer-Related. Acquired, and Congenital
Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub.
2011.PAGE NO.191

 Any Class II maxillary RPD-obturator prosthesis must be effectively retained to
achieve its functional objectives.
 Support and, to a certain extent, stability are important cofactors as they help to
maintain the correct retainer-to-tooth relationships so that the retainers serve
primarily as a rescue force to compensate for dislodgment or gravitational forces.
 If the support, stability, and retention for the resection prosthesis can be enhanced
by engaging selected areas within and peripheral to the defect, the retention,
stability, and support available for the partial denture will be enhanced and
retainer- to-tooth relationships will be maintained
 fewer retainers will be required in this situation than when a defect lacks these
important physical characteristics
Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects
of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE

 Incisal and cingulum rests do not improve support as effectively as
occlusal rests on posterior teeth.
 Less tooth structure is available for rest preparation and it may be more
difficult to direct masticatory forces along the long axis of anterior
abutment teeth
two different design
suggestions for partial dentures
for selected total maxillectomy
defects:
When stability and support are
limited teeth may be used to
improve these aspects
Multiple, well- prepared , and well-
spaced rest seats, especially on
posterior teeth, will enhance
support.
If stability is
inadequate
Lingual
plating
Widened
minor
connectors
Long and
wide guiding
planes
The horizontal bracing associated with these
partial denture components will enhance the
overall stability of the prosthesis, especially if
retention and support are adequate.

 Some clinicians have suggested the addition of lingual retentive clasp arms with buccal
reciprocating arms so that, as the prosthesis is displaced superiorly, the lingual
retentive arms will disengage from the teeth.
 Disengagement is an asset , but these designs exhibit greater motion around the
fulcrum line , which decreases retention.
 The effectiveness of lingual retention will depend on the angulation of the abutment
teeth relative to the occlusal plane.
 Because there is no cross-arch reciprocation for either buccal or lingual retention, a
partial denture framework for a patient with a total maxillectomy must be viewed in
the same light as a unilateral RPD, with the important exception that the framework is
supporting a large outrigger.
 For this reason, both buccal and lingual retentive arms may be considered to obtain
cross-tooth retention and reciprocation.
 In this situation the fulcrum line closely approximates the teeth and the indirect
retainers will be close to or on this fulcrum line and thus less effective.
 Therefore, this particular prosthesis will have the potential for more movement around
the fulcrum line
Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.192

 Dentate patients - learn quickly to masticate primarily on the nondefect side
 Any segment of the food bolus for a total maxillectomy patient is most likely be placed on the
more anterior teeth during the act of incising.
 If the occlusal forces are applied to a bolus on anterior replacement teeth , the fulcrum would
shift slightly posteriorly on the defect side.
 The further posteriorly the bolus and the forces are applied on the defect side, the further
posteriorly the fulcrum line shifts on the defect side
 Unstable and nonretentive maxillary resection partial dentures are likely to exhibit more
extensive movement when the fulcrum line is more posteriorly located on the defect side.
importance of saving the
anterior maxillary segment
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation:
Surgical and Prosthodontic Management of Cancer-Related. Acquired,
and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL:
Quintessence Pub. 2011.PAGE NO.192

Impressions for the framework
Restorative
procedures
• Tooth
preparations
Minor changes
to inter rim
obturator
prosthesis
• compensate for
tooth contour
changes
Block out
medial
palatal
undercuts
• gauze
lubricated
with
petrolatum
Bony undercuts in this
region can result in
distortion of the palatal
portion of the
impression, when
irreversible hydrocolloid
is used.
Hydrocolloid
or polyvinyl
siloxanes
PVS
DEFECT PORTION
WITH SLICONE
PUTTY
DENTITION WITH
MEDIUM BODY
IMPRESSION
MATERIAL

 The lateral portion of the defect should be recorded - necessary to fabricate the
tray for the future altered cast impression
 The obturator portion of the prosthesis will be constructed of acrylic resin to allow
adjustment and relining.
 Finishing lines of the cast metal framework should be established on palatal
mucosa short of the palatal shelf
 The retention loops for the obturator portion should extend well across the palate,
and in some instances into the defect, and should be located approximately 0.5 to
1.0 mm superior to normal palatal contour.
 The retention should not be placed high in the defect because it becomes more
difficult to hollow the obturator sufficiently without compromising the retention of
the resin portion of the prosthesis
NO.193

 The RPD framework is physiologically adjusted through the use of an appropriate
disclosing medium while the framework is rotated along the predicted axes of rotation
 When the framework seats properly and has been physiologically adjusted , the
undesirable undercuts within the defect are blocked out on the cast with baseplate wax.
 Relief is also placed over the scar band and lateral wall
 Tray resin is molded to the framework and the defect in preparation for the altered cast
impression
The prosthesis is placed
in the mouth and the
tray is examined for
extension and proximity
to the tissues.
Modeling compound is
added to the tray
material until the desired
extensions have been
achieved

.
Retention , stability, and
seal of the prosthesis are
checked
If inadequate - extension
into an undercut and
refinement of the portion
interfacing with the soft
palate
Recognition of the dual
path of insertion required
to fully engage the lateral
wall of the defect and final
seating of the framework
can be helpful
When access to the lateral wall of the defect is
impaired , making it difficult to record the undercut
in this area
A hole in the tray and
manipulate the compound
digitally through the hole
The posteromedial
extension must be
carefully developed to
minimize leakage of
food and liquids,
particularly when the
defect extends in the
movable portion of the
soft palate
should be extended about 1 cm
vertically or in some instances
overlap the nasal side of the soft
palate

Impression can be
extended to the level
of the occlusal plane
on the defect side
occlusal index is made
Finished prosthesis,
including replacement
teeth, will not be
oversized
Modelling plastic is
relieved
If an elastic impression material is used to complete
the impression, escape holes are placed along the
medial palatal finish line to permit the escape of wash
material.
A suitable adhesive is applied to the border-molded
impression and up to the finish line but not to the
major connector
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of the Head and
Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.194

 Among the elastic impression materials, preferred one is polysulfide
 Before the framework is seated , medium-bodied polysulfide material is injected in
the undercuts that are to be recorded
less likely to
displace tissues
in the defect
less likely to
flow into
undesirable
areas
After the casting is seated , the patient is directed
to make eccentric mandibular movements
examined for tissue
adaptation , proper
extension , and excessive
displacement of tissue
NO.194

 Thermoplastic wax, used alone or in combination with an elastic impression
material, can also be used to complete the impression
Modeling compound is used to develop the contours of
the impression that extend into the defect or to
establish the extensions of other edentulous areas
When a thermoplastic wax is used to
refine the impression , it is necessary to
extend the modeling compound to the
level of the occlusal plane and develop
an occlusal index.
(impression remains properly seated
during the molding of the impression
wax)
The modeling plastic that forms
the obturator is then cut back 1
to 2 mm, and the entire
impression is covered with a
thermoplastic wax.
NO.194

 The impression is inserted and refined with the border molding maneuvers
previously described.
 It may take several insertions and removals and further cutbacks before the
impression is suitably covered with a proper thickness of wax (1 to 2 mm).
 The patient is allowed to wear the prosthesis for 60 to 90 minutes.
 It is then removed , inspected, and chilled .
 Next , the altered cast impression is boxed and poured, and the cast is mounted on
the articulator using the occlusal index
 To maintain accuracy of the occlusal index, the cast must be trimmed and
mounted on the articulator prior to separating the impression from the master
cast.
 Elastic materials are favored for smaller static defects or when there are large
undercuts that must be recorded.
 Thermoplastic wax is preferred for large or dynamic defects where the obturator
approximates mobile border tissues or extends into the velopharyngeal complex
Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.194

 Make tentative centric relation
registrations simultaneously with
the altered cast impression of the
defect (verified at the time of trial
denture insertion)
 Another method is to make a record
base on the blocked-out master cast
resulting from the altered cast
impression.
 A centric registration is then made
with this record base in the usual
and customary fashion.
Another method employs a processed record base.
With this technique, the record base is processed
into heat-activated acrylic resin using the altered
master cast , and the denture teeth are attached at a
later date
patients with large or unfavorable defects.

 In the posterior region , centric-only contact is preferred on the defect side.
 If possible, all guidance should be on the remaining natural teeth on the defect
side.
 lingualize the occlusion.
 If the defect extends to the anterior region, the incisal angle of the anterior teeth
should be flattened to avoid anterior guidance on the defect side.
 This can be accomplished by raising the anterior teeth on the side of the defect or
setting them slightly labially.
 Lip contours generally permit these alterations

 Most resections of paranasal sinus neoplasms extend into the anterior region.
 To properly retain the RPD-obturator prosthesis in position, the tooth adjacent to
the defect should be engaged with a positive rest and a retainer.
 The I-bar is preferred; in most patients, just the tip of the retainer is visible
during a high smile.
NO.196

In this patient the two
central incisors were
splinted together, and a
cingulum rest was
placed on the maxillary
right central incisor
Following endodontic
treatment, the maxillary right
third molar was restored with a
gold coping and an attachment
was incorporated within it
A bracing arm was
placed between the
premolar and the
canine on the
unresected side to
ensure that the RPD
framework remains
properly
seated on the occlusal
and cingulum rests
during function
For patients in
whom the resection
terminates short of
the second or third
molar, the use of
precision
attachments can be
considered.
2011.PAGE NO.196

 Lip plumpers are occasionally useful in selected
maxillectomy patients when facial nerve weakness or
injury results in drooping of the corner of the mouth on
the side of the defect.
 Conventional prosthodontic methods are followed to
complete the RPD-obturator prosthesis.
 The obturator portion is processed in a hollow
configuration
 The lateral and posterolateral extensions are polished.
 Delivery and adjustments are accomplished in
accordance with acceptable prosthodontics guidelines

 Slight pressure against the skin graft and cheek mucosa is
desirable to ensure maximal retention, stability, and support.
 Disclosing wax is preferred over pressure indicator paste to
identify areas of excessive tissue displacement in the defect.
 Anterior and posterolateral portions of the defect are most
susceptible to displacement during impression making and
must be checked carefully.
 Following these adjustments, the lateral and posterolateral
extensions are polished
tends to stick to the
skin graft or other
dry surfaces in the
defect
will be displaced or
distorted when the
prosthesis is seated
in undercut areas
Pressure indicator paste

 Oh and Roumanas - used for large obturator prostheses.
 After the altered cast impression is poured, one layer of baseplate wax is adapted
to the master cast
 Additional wax may be added to eliminate undercuts to facilitate trial packing.
 The wax should extend to join the finish line of the metal RPD framework.
 Flasking and packing are conducted in the usual manner.
 Following polymerization, the record base is divested and finished.
 The record base is then refined intraorally with pressure indicator paste and
disclosing wax.
 Wax rims are added and records are made and transferred to the articulator

 The record base- trial denture is flasked , and the second
processing in heat –activated acrylic resin is conducted at 138°F
for 12 hours.
Ensures even
thickness
Negligible
distortion
Minimises
weight
allows
maximum
extension into
the defect
ADVANTAGES
Idealizing the support , retention, and
stability of the record base when records
are made.
More accurate centric records
are the result
lower
temperatur
e and a
longer
processing
cycle are
employed
Teeth are
arranged ,
and the
esthetics
and the
centric
relation
record are
verified in
the usual
manner

 Prosthetic prognosis improves as the anterior margin of the resection moves
posteriorly.
 When the maxillary canine on the defect side remains, the prosthetic prognosis
improves dramatically.
 The fulcrum line is dependent on the placement of occlusal rests.
 As more teeth are retained on the defect side, the fulcrum line shifts posteriorly.
 When both canines remain , the fulcrum line will be similar to that of a
conventional Kennedy Class II partial denture.

 As the fulcrum line shifts posteriorly, the superior distolateral extension of the
obturator should be lengthened; extension into this area offers the greatest
mechanical advantage because it will be at a right angle and most distant from
the fulcrum line.
 Indirect retainers should be placed as far anteriorly as feasible from the fulcrum
line.
 As with total maxillectomy patients, a retainer placed on the tooth closely
adjacent to the defect increases stability and retention

 The construction and fitting of the prosthesis are carried out as described for
prostheses fabricated for total maxillectomy patients.
 Occasionally edematous turbinates extend into the oral cavity, preventing
restoration of normal palatal contours
 If so, the turbinates should be removed surgically
Small defects
should be
blocked with
gauze before
impressions are
made to prevent
escape of
impression
material into the
paranasal
sinuses

 Defects bordering the hard and soft palates
 Resection of some tumors pleomorphic adenomas and small , well-localized
squamous cell carcinomas may require a limited surgical resection at the junction
of the hard and soft palates.
 Alveolar ridge and teeth are only minimally involved in the resection.
IL: Quintessence Pub. 2011.PAGE
NO.197,198

 Speech will be normal after delivery of the prosthesis.
 When there is excess nasal leakage when swallowing - a 5- to 10- mm extension
with positive pressure is created across the intact oral side of the soft palate.
 The soft palate will lift from this extension in function , but this shield will serve
to direct liquids and food into the oral pharynx.
 Leakage will be minimized without interfering with tongue function.
 Extension into the defect that allows for contact with the nasal side of the soft
palate during elevation also is suggested
Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.197,198

Anterior defects
If a skin graft is placed , scarring
and retraction of the lip is
minimized, the prosthesis can be
extended into the defect to support
the lip, and an acceptable esthetic
result can be achieved
IL: Quintessence Pub. 2011.PAGE NO.198

 When both maxillae have been excised , the prosthetic prognosis is quite guarded.
 Prostheses constructed for these patients are primarily intended to improve speech
and esthetics.
 Surprisingly, they serve these functions well.
 However, without bony support, the prosthesis will exhibit considerable movement
during swallowing and mastication.
 Consideration should be given to creating undercuts during resection of the tumor.
 Retention, stability, and support are enhanced if these surgical undercut areas are
located bilaterally and lined with a split-thickness skin graft.
Bilateral total
maxillectomy
defects do not
occur
frequently.
Beumer J, Marunick MT, Esposito
SJ. Maxillofacial Rehabilitation:
Surgical and Prosthodontic
Management of Cancer-Related.
Acquired, and Congenital Defects
of the Head and Neck. ed
3Hanover Park, IL: Quintessence
Pub. 2011.PAGE NO.198,199

 Implants may be quite useful for selected patients.
 Engagement of the nasal aperture and the nasal side of the soft palate is
useful in some patients.
 Two- piece prostheses enable more efficient use of available soft tissue
retentive areas.
Congenital Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.198,199

 Occasionally a maxillectomy defect will extend posteriorly to the pharyngeal wall.
 Very large prosthesis - can restore speech and swallowing to normal levels, if
retention is adequate
 masticatory performance - presence and location of teeth and /or implants.
 midlateral portion, replacing the hard palate - aggressively engage the defect to
idealize stability, retention, and support
 velopharyngeal extension must precisely engage, interact with, and be positioned
within the zone of residual velopharyngeal muscular function.
 If a non-functional band of soft palate remains, access to the pharyngeal
musculature sometimes can be gained through the defect over the nasal side of
the soft palate
Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.199

 Corrected velopharyngeal portion must be completed with a thermoplastic wax.
 one-step impression method that records the palatal and velopharyngeal portions during
the same appointment is preferred
 After border molding is completed, an occlusal index is made to stabilize the impression
while the velopharyngeal portion is being refined .
 The entire impression is border molded with a low-fusing dental compound .

 Following a suitable cutback, the entire impression is refined with a thermoplastic
wax
 The prosthesis is then completed in the customary fashion
 With good retention, adequate movement of the residual velopharyngeal
musculature, and precise placement of the velopharyngeal extension, speech and
swallowing are restored to normal
Defects of the Head and Neck. ed 3Hanover Park, IL: Quintessence Pub. 2011.PAGE NO.199,200

 About one-quarter of patients undergoing total
maxillectomy require orbital exenteration.
 Otherwise, saliva will leak onto the skin by
capillary action.
 It is advantageous to connect the orbital
prosthesis to the obturator prosthesis - enhance
the retention of the orbital prosthesis and the
support, stability, and retention for the
intraoral prosthesis
(left)(a and b) The posterior extension
is aggressive but the lateral extension
is short of the
external surface of the defect
If the orbital defect is unusually large ,
the lateral extension of the obturator
prosthesis should be short of the height
of contour between the oral defect and
the skin side of the orbital defect
Pub. 2011.PAGE NO.199,200

 On occasion, removal of large portions of the
orbital floor is necessary to ensure tumor
control
 Following resection of the orbital floor, facial
slings and split-thickness skin grafts are
usually inserted to reinforce the orbital
contents.
 The fusion of the skin graft and periosteum
creates a hammock that, in some instances,
adequately supports the orbital contents.
 prostheses that elevate the orbital floor are
often useful in providing support for the
orbital contents.
Ptosis
enophtalmos
Cosmetic
misalignement
of eyes
Persistent
dipopia
significant
amounts of the
periorbita are
removed -
compromise the
action of the
inferior oblique
and inferior
rectus muscles,
the incidence of
diplopia
increases
Uplifting the orbital contents will improve cosmetic appearance
and often reverse the diplopia

 The prosthesis may be fabricated as a one piece prosthesis in which the antral
extension is attached directly to the obturator section or in two sections in which
the superior orbital extension is connected via an attachment to the parent
prosthesis.
 The antral section may be flexible or rigid.
 A flexible apparatus is advantageous because it is light and can be designed so
that transmission of movement generated by the parent prosthesis during
function can be minimized.
 Care must be taken to avoid excessive contact with and trauma to adjacent nasal
mucosa.
NO.200

 Difficult to restore
 physical configuration of traumatic palatal defects varies
considerably (dependent on the nature of the injury)
 lined with a combination of pseudostratified columnar
epithelium or poorly keratinized squamous epithelium as
opposed to skin grafts
 In most patients, the lateral wall contracts and is not
divergent and therefore is not as effective in preventing the
prosthesis from rotating out of the defect - additional stress to
residual dentition or implants to retain the prosthesis
Large avulsive defect of
the maxilla (usually
irregular and
lined with poor-quality
mucosa.)
Palatal defects secondary to
trauma

 The soft tissues bordering the traumatic defect are
often heavily scarred and cannot be as easily
displaced or recontoured by the prosthesis
 The residual maxillary segments in patients may be
displaced and lack bony attachment to the base of the
skull.
 Difficult to establish proper occlusal relationships in
patients with traumatic defects.
NO.200
facial esthetics is often
compromised
Compromises support and
may subject abutment
teeth to unfavorable
lateral torquing forces
The arrangement of
mandibular dentition, the
mandibular arch form, and
the occlusal plane of the
mandible may be less than
ideal

 usually extends from 2 to 6 months.
 provisional prosthesis, provided for esthetic and phonetic reasons, may be used to
refine and stabilize the occlusion.
 reveal other potential prosthodontic problems and help the patient develop more
realistic goals.
 At the same time, these prostheses provide a general sense of well-being so that
the patient can anticipate future progress.
 Displaced maxillary fragments in unfavorable positions should be repositioned
surgically if possible.
 Small oroantral fistulae should be closed.
 Large palatal defects with sufficient dentition to retain a prosthesis should be left
open

 lining potential denture-bearing and/or usable undercut areas with a split-
thickness skin graft.
 Teeth may be properly positioned and functional palatal contours can be restored.
 Support for the lips and cheek can be developed more effectively if the maxillary
prosthesis is stable.
 Vascularized soft tissue flaps, in contrast, are generally not recommended because
the result is mobile, nonfunctional soft tissues that cannot be used to effectively
support the prosthesis.
 In addition, soft tissue flaps used to close these defects are often bulky, resulting
in unfavorable palatal contours and often compromises the position of the denture
teeth .
 As a result , articulation, swallowing, and esthetics may not be restored to optimal
levels.
NO.200

 Surgical closure and reconstruction of large traumatic defects with vascularized
osteocutaneous flaps are dependent on the need to provide bony anchorage for
osseointegrated implants - fibula is the desirable donor site.
 It is critical to determine the definitive long- range treatment plan during this
phase of care and to coordinate this treatment plan with the other appropriate
health care disciplines.
 All necessary adjunctive consultations and dental treatment, such as endodontics,
periodontics, and orthodontics, should be completed prior to definitive
prosthodontic treatment
 The patients ability to maintain oral hygiene, willingness to keep recall
appointments, and capacity to develop adequate dexterity for the placement and
care of a prosthesis are other important factors to be considered .
 Potential influence of other bodily injuries and the level of family support should
be assessed.
 Psychosocial interventions may be critical at this stage
NO.200

Study
casts
Scans
3D
models
residual maxillary
or mandibular
segments -
misaligned
Remaining
maxillary segments
are not well secured
to the cranial base
maxillomandibular
relationship is
altered
Irregular occlusal
plane
These issues must be addressed
surgically before definitive prosthodontic
treatment is considered
Unfavorable tooth position
and alignment and may
compromise future RPD
designs and implant
placement.

major connectors should be
rigid
occlusal rests should direct
occlusal forces along the
long axis of the teeth
If implants are used to
supplement the dentition,
should be positioned and
the attachments designed
to direct occlusal forces
along the long axis
guiding planes should be
designed to facilitate
stability and bracing,
retention should be within
the physiologic limits of the
periodontal ligament
maximum support and
stability should be gained
from the residual soft
tissue denture- bearing
surfaces, including the
defect
The basic principles of partial denture design should be followed
NO.201

 Altered cast impressions of the denture bearing tissues and the defect are made after
the RPD framework has been fitted and physiologically adjusted .
 Inappropriate areas on the cast are blocked out with wax, and tray resin is molded to
the framework and the defect area .
 The framework and resin extension are checked in the mouth for the path of insertion
and removal and tissue impingement.
 Approximately 1 to 2 mm of space should exist between the resin base and the
peripheral defect tissues.
 Scar tissue can be especially unyielding in the trauma patient .
 Therefore, these areas must be carefully checked for proper clearance

 Modeling compound is
added to the tray until the
desired extensions have
been achieved.
 After the modeling
compound is cut back -
refine the border-molded
impression of these
defects with a
thermoplastic wax (nature
of the soft tissues lining
traumatic palatal defects)
 soft tissues in the defect
are highly variable
(epithelial coverage and
tissue displaceability) -
functional impressions
will result in better
adaptation and fewer
adjustments during the
delivery and follow- up
period
The impression is boxed and conventional prosthodontic methods
are followed to complete and deliver the prosthesis
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation:
Surgical and Prosthodontic Management of Cancer-Related.
Acquired, and Congenital Defects of the Head and Neck. ed

Possible
impact on
speech
clinical evaluation alone may not
reliably determine the adequacy of
obturation
Level of comfort,
function and
esthetics
functional
limitations
induced by the
surgery
efficiency of
mastication
leakage of
air and fluid
into the
nasal cavity
contribute
to the
patient’s
perceptions
of health -
related QOL
A patient with a maxillary
resection prosthesis is
compromised in the capability of
bilateral chewing because of the
defect and nueuromuscular control
because of surrounding sensory
deficits.
NO.202

 The added movement of the edentulous maxillary resection prosthesis into the
defect accentuates this functional disparity.
 Retention in the classic sense of complete dentures is unobtainable because the
surgical opening permits the leakage of air beneath the prosthesis and eliminates
the retentive contribution of atmospheric pressure.
 While both dentate and edentulous maxillectomy patients may learn to confine
most of their mastication to the nondefect side, mastication comparatively is much
more effective in dentate patients.
 As discussed previously, the size and location of the resection, the contours of the
remaining alveolar ridge and palate, and the potential for retention , stability, and
support within the defect will influence the level of function of both dentate and
edentulous patients
NO.202

 Shipman" studied 10 edentulous patients with maxillary resection obturator
prostheses.
 A gnathodynameter was attached to each prosthesis.
 The maximum bite force recorded was approximately50% of the forces reported for
conventional complete denture patients and had little relationship to the size of the
maxillary defect
 Denture adhesives increased bite force by approximately 12%.
 However, there was considerable variation in the forces recorded between patients,
and the individual standard deviations were high .
 defect contours and neuromuscular control may be important cofactors in the
performance of patients with obturator prostheses; however, factors including nsation
and motor coordination are critical to masticatory function.
 Relying on only force as a surrogate may be misleading.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed

Matsuyama et al
 found that bite force was a poor
predictor of masticatory performance
in maxillectomy patients treated with
a conventional obturator, at least when
residual dentition remained in the
maxilla.
 Maxillectomy patients treated with a
conventional obturator, most of whom
had residual dentition for obturator
support and chewing, were found to
perform at levels similar to dentate
controls.
 bite force was significantly reduced in
the maxillectomy group, the presence
of the critical residual dentition ,
combined with the obturator, resulted
in masticatory performance that was
not significantly different from dentate
controls.
 The presence of remaining dentition is
clearly an important factor in the
restoration of masticatory function.
Koyama et al
 found that edentulous patients
restored with a conventional maxillary
obturator only achieved slight
improvements in masticatory
performance postsurgically, only
reaching the compromised level
observed prior to surgical intervention.
 Even with the conventional obturator,
chewing was significantly impaired
compared to that of complete denture
wearers who had not undergone a
maxillectomy.
found that the remaining maxillary teeth had a
strong relationship to patients’ perceptions of
masticatory function .
Garrett
NO.202

 When the retention and stability of the obturator are improved with implant
retention, significant additional improvements in masticatory performance may be
obtained for selected patients, particularly those with natural dentition in the
mandible, for both the surgical defect side and the nondefect side.
 These improvements in performance may approach the level of a conventional
edentulous patient restored with implant-supported dentures.
 However, the performance levels achieved remain considerably impaired relative
to those of “normal” dentate individuals

 complain of varying amounts of fluid leakage around the
periphery of the obturator and into the nasal cavity.
 frustrating for both the patient and the prosthodontist.
(with some leakage of air, speech is often within normal
limits). Study of Watson and Gray
leakage around the obturator is greater during sustained exhalation compared to initial exhalation
There was some leakage even with initial exhalation
The effectiveness of obturation was measured by comparingduring both initial and
sustained exhalation while the patient exhaled was measured
with and without a nose clip Into a spirometer
Studied 5 patients using 2 methods
Simple lung function tests
Sequential radiographic assessment of a radiopaque
liquid during swallowing
NO.202

soft tissues peripheral to the obturator contract more vigorously during forced
exhalation , leading to improved seal .
With sustained exhalation, forceful exhalation is not feasible and hence leakage is
more likely to occur
Radiographic evidence
confirmed the leakage
of contrast medium
around most
obturators, especially
along the
posteromedial and
posterolateral margins
of the defect when the
obturator was
underextended or
improperly contoured
in these areas
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management
of Cancer-Related. Acquired, and Congenital Defects of the Head and Neck. ed 3Hanover Park, IL:
Quintessence Pub. 2011.PAGE NO.202

 Leakage may occur posteriorly during swallowing due to the movement of the soft
palate.
 Posterolaterally, the functional movements of the coronoid process may contribute to
leakage.
 During mandibular movements, the coronoid process and the anterior border of the
ramus of the mandible displace the soft tissues along the distolateral aspect of the
defect, just as these structures influence the width and lateral contours of the buccal
pouch area of a maxillary complete denture.
 Movements of the coronoid process must be accounted for or post delivery soreness will
result
 During swallowing, the mandible is closed and braced so that a small space may exist
where the soft tissues were distended during mandibular movements.
 During swallowing, the dorsum of the tongue elevates forcefully against the hard and
soft palates, creating a pressure superiorly that may force fluids around the obturator
bulb and into the nasal cavity.
 complete and total closure or seal may be unobtainable at times, but a sufficient level of
obturation usually exists to permit acceptable speech and swallowing
NO.202

.
 studied four patients with maxillary obturator prostheses using the methodology
based on airflow, pressure, velopharyngeal orifice size, and respiratory volumes
4 patients
2
Partial
maxillectomies
1
Complete
resection of
both maxillae
1
Complete
resection of soft
palate
Oral pressures
and
respiratory
volumes were
recorded
during the
production of
consonant
sounds both
prior to and
during each
phase of
prosthodontic
treatment
While wearing
the prosthesis
Without
wearing the
prosthesis
The oral opening around the
definitive obturators was less than
0.05 mm- no impact on speech but
might lead to the percolation of
fluids into the nasal cavity during
swallowing.

confirmed the efficacy of this methodology by reporting the data of
three patients requiring maxillary maxillofacial prostheses
Patients often
experience difficulty
identifying the exact
location
where the leakage is
occurring
Sensory deficits
associated with the
surgical resection
Altered and
compromised
innervation arising
from skin graft
linings in the defect
direct visualization of the interface
between the peripheral
soft tissues and the obturator bulb
during swallowing can be
helpful
Approximately 25% of the time, the contents of the orbital cavity must be
exenterated in continuity with the maxillary resection for control of the disease,
thus permitting direct visualization of the superior surface of the obturator
through the orbit
Oral endoscopy
nasoendoscopy
with a fiber -
optic light
source

 Surgical removal of portions of the maxillae can create a serious problem for the speaker
for several reasons.
•patient cannot confine oral emissions within the oral cavity – hypernasal speech
Oral nasal resonance balance is distorted
•Articulation is compromised
•17 of the 25 consonant phonemes used in the English language require labiodental , linguodental , and
linguopalatal contacts
With the loss of palatal tissues, correct tongue- palate contacts are impossible
•loss of anterior teeth (associated with a total maxillectomy)
Compromised articulation of speech
Several investigators have reported that patients exhibited normal speech after placement of
prostheses for acquired surgical defects of the maxillae
NO.203

.
Speech recorded 6 patients
3 patients
edentulous
3 patients
Dentate
2 – improved
speech
3 – slight
loss ( up to
14% )
1- 18% loss
in
intelligibility
patients undergoing maxillectomy procedures
for control of neoplastic disease
speech
following
placement
of the
prosthesis
may not
always be
normal
After surgery, the
patients recorded the
same speech sequence
at intervals up to 9
months postsurgically
both with and without
use of the prosthesis
In this patient,
the resection
extended well
into the soft
palatal area
maxillary resection may affect velopharyngeal function by
destroying the attachments for the palatal musculature,
by coincident denervation of the palatal muscles, or by the
relative shrinkage and immobilization of the soft palate
through scar contracture

A speech sample was recorded presurgically, while the patient wore the ISO, and following placement of
the definitive prosthesis.
The speech samples were randomized and evaluated by 10 untrained listeners following a period of
instruction.
The average intelligibility of all subjects was 98.8% correct presurgically, 92.1% correct with their ISOs,
and 97.3% correct with their definitive prosthesis.
One patient with a prosthesis for a bilateral maxillectomy defect exhibited a 12% reduction in
intelligibility with the definitive prosthesis
studied the speech of eight patients,
both dentate and edentulous,
rehabilitated with a maxillary
obturator prosthesis following surgical
resection of various segments of the
maxillae

were able to assess speech intelligibility, speaking rate, nasality, and communication effectiveness in a
relatively large sample of 32 maxillectomy patients obturated for at least 1 month
Sample included a wide range of defects, including hard and /or soft palate, with 2 to 8 patients in
distinct defect categories
The defect size and location likely
have significant impact on
restoration of speech , but the limited
size of samples for comparison makes
it difficult to provide a definitive
conclusion
30% improvement in the mean
speech intelligibility ratings
communication effectiveness
returned to 75% of the level prior to
cancer diagnosis

Defects involving the complete
soft palate and defects
compromising
the retention of the conventional
prosthesis performed
more poorly than the remaining
sample.
hypernasalty was found to have a strong relationship with
communication effectiveness
With obturation , all defects except
for the combined unilateral hard
and soft palate defects achieved
intelligibility scores great than
95%.

They examined the acoustic speech
patterns patients before and after
prosthodontics reconstruction to
determine the effectiveness of maxillary
resection prostheses in eliminating or
reducing nasal resonance.
A digital sonograph with a 30-Hz filter
was used to record speech
samples presurgically and after
prosthodontic rehabilitation.
Vowels were primarily studied - sensitive
to changes in nasal resonance and their
production requires different areas of
tongue- palate approximation
5
2
Resection confined
to anterior maxilla
3
included the
posterior maxillae
and varying
portions of the
anterior soft palate
Excess
nasal
energy
was
found in
the
speech of
all five
patients
proportionally less
nasal resonance
Acoustic and aerodynamic patterns of
speech can provide a better
understanding of the basis for the effect
of obturation on
speech intelligibility

used more advanced nasalance
measures and size estimates of
the opening between
the oral and nasal cavities
 Evaluations of 12 maxillectomy patients were made prior to surgery,
postsurgically without obturation, and postsurgically with obturation
For the total sample, average speech
with obturation was not significantly
different
than the preoperative speech
Speech was significantly impaired
without obturation
defects that involved the soft palate
exhibited poorer speech (nasalance)
values postsurgically, even with
obturation

Based on clinical observations, when the maxillectomy is confined to the bony palate, the speech
following placement of a prosthesis is usually within normal limits.
Rarely is velopharyngeal function affected (either directly or indirectly) through scar contracture, loss
of bony attachment for the soft palate, or denervation.
However, it is not uncommon for slight articulatory deficiencies to be associated with speech following
placement of the definitive prosthesis.
Resonance balance usually is normal.
In a few patients more extensive distortions in articulation and resonance have been noted .
As indicated in the recent research , these distortions seem to be associated with more extensive
resections of the soft palate and /or patients who are edentulous
These errors in articulation tend to diminish as the patient uses the prosthesis, but speech therapy is
sometimes required for patients who experience difficulty in adaptation

noted this tendency for
improvement in
articulation of
speech following the
placement of prostheses
 The speech result with the definitive prosthesis may not be as effective initially as the
results achieved with the surgical prosthesis.
 Occasionally, the same slight deterioration in speech may be noted following the construction
of a new definitive prosthesis.
 Introduction of a major change in the prosthesis will require a period of neuromuscular and
functional adaptation , and patients should be prepared for this occurrence.
 These sequelae do not occur frequently, but when they occur it may be discouraging to both
the patient and prosthodontist , and this negative feeling may compromise adaptation to the
new prosthesis.
 Usually, with modification of the prosthesis, persistence in adaptation by the patient, and
support and encouragement from the prosthodontist, these speech deficits are eliminated or
minimized .
 Fortunately, few' total maxillectomies adversely affect velopharyngeal closure as described
by Bloomer and Hawk

 When innervation is compromised , resulting in velopharyngeal incompetence, or
when scar contracture results in velopharyngeal insufficiency, the addition of a
palatal lift extension to the obturator may improve velopharyngeal closure.
 Research and controlled studies are indicated for further evaluation of speech and
fluid leakage following placement of maxillary prostheses for acquired palatal
defects.

 surveyed 47 maxillectomy patients
who had worn an obturator
prosthesis for an average of 5 years
 94% ofthe sample had at least some
soft palate resection.
 Using a variety of scales to assess
perceived function, treatment
satisfaction, and mental state, the
researchers found that satisfactory
functioning of the obturator was
significantly related to psychologic
adjustment and QOL.
Functional and esthetic impairments produced
by the maxillectomy can have a negative impact
on the psychologic state of the patient and their
perceived QOL..

 extended the evaluation of QOL in obturated maxillectomy patients to include comparison of
similar patients restored with a free flap.
 Assessments included a series of wellvalidated, head and neck-oriented, health-related QOL
instruments, including the University of Washington QOL Scale (UWQOL); the European
Organization for Research and Treatment of Cancer (EORTC) QOL Questionnaire, Core (QLQ-
C30) and Head & Neck (QLQ-H&N35) modules; and the same obturator function scale used by
Kornblith et al
 No statistically significant difference in patient perceptions were found among 28 patients
treated with obturators and 18 patients undergoing free tissue reconstruction.
 Overall, the size of the defect was found to be related (the larger the defect, the greater the
negative impact) to the activity and recreations domains (UW-QOL) and the physical functioning
and overall QOL domains (EORTC QLQ-C30).

 In large defects, much of the support, retention, and stability for the obturator
prosthesis is derived from the soft tissues of the defect, and these tissues are
subject to change.
.
 refine must be performed with care and precision so that centric relation and the
vertical dimension of occlusion are maintained.
most
noticeable
during the
first 18
months
following
surgery
• tend to stretch with timecheek surface and scar band at
the junction of the skin graft
and oral mucosa
• subject to change if it extends into the area of
velopharyngeal function.Posterior margin of the defect
• remodels and becomes rounded
Medial bony margin of the
defect
NO.205

Undercut areas of the obturator portion are removed
Acrylic resin adjacent to the finish fine of the major
connector is reduced
this zone is perforated in several regions with a No.
4 round bur
contours of the prosthesis are redeveloped with
modelling plastic (border mmoulding)
modeling plastic is reduced 1 to 2 mm and either a
thermoplastic wax or elastic impression material is
used to refine the impression
Thermoplastic
wax is
preferred if
the defect is
large and
exhibits
mobile
peripheral
tissues.
Wax reline of
edentulous patient
NO.205

impression is boxed and poured
A reline jig is used so that all relationships are maintained
The reline jig is disassembled, the impression material is
removed, the residual acrylic resin is reduced where necessary,
and the reline is completed with autopolymerizing acrylic resin.
The relined obturator prosthesis is delivered
Pressure indicator paste and disclosing wax - verify proper
adaptation and extension into the defect.

 Prosthetic techniques can provide excellent rehabilitation for patients with
maxillary or combined maxillary and soft palate defects.
 Some patients encounter lasting problems with the retention of the prosthesis or
favor a final closure of the defect for other reasons, such as psychologic
acceptance.
 Particularly for younger patients, a planned surgical reconstruction of missing
soft and bony tissues, in combination with prosthetic restoration of missing teeth,
may be desirable.
 If surgical reconstructions are not properly planned and executed, irresolvable
prosthetic difficulties may arise from poorly contoured, bulk tissues or a lack of
suitable bone volume for placement of implants

 new surgical and prosthodontic techniques are evolving; when properly executed
in a multidisciplinary environment, these methods provide patients with implant-
supported prostheses that very effectively and predictably restore form and
function.
 These techniques are used to preplan the rehabilitation of maxillary defects based
on the occlusion and dental configuration of the opposing mandible.
 A bone transplant, most often a free vascularized graft, is used to replace the
missing alveolar bone with sufficient volume and density to retain an implant-
retained prosthesis
NO.205

 As part of a two-stage procedure, the graft initially is preprepared: Implants are
placed in the donor bone and new periimplant tissues are created by placing a
split-thickness skin graft around these implants.
 In the stage-two procedure, the graft is harvested, the bone is osteotomized as
needed, and the graft is secured to the preprepared prosthesis.
 The graft is secured to the residual maxilla and skull base to create a new maxilla.
 The remaining palatal defect can be closed with the soft tissues associated with
the flap or with an overlay denture.
Beumer J, Marunick MT, Esposito SJ. Maxillofacial Rehabilitation: Surgical and Prosthodontic Management of Cancer-Related. Acquired, and Congenital Defects of the

 In general, this technique is best suited for secondary reconstruction after the
patient is proven to be free of disease.
 It can be used in both dentulous and edentulous patients.
 However, in selected patients, for example, those with well-defined benign tumors,
a primary preplanned reconstruction can be combined with preplanned guided
tumor ablation.
 However, this approach is generally not preferred.
 If a vascularized free flap is to be used, the conditions of both the donor site and
recipient site vessels must be carefully assessed.
 Vascular disease with partial occlusion of blood vessels in the donor site is
considered a contraindication because it might lead to severe vascular problems in
the donor region

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