Miscellaneous prosthesis /orthodontic practice

Miscellaneous
Maxillofacial prosthesis
INDIAN DENTAL ACADEMY
Leader in continuing dental education
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Maxillofacial prosthesis
Tissue
retained
MP
IMPLANT
retained
MP
TOOTH
RETAINED
MP
IMPLANT /
TISSUE
RETAINED
MPCranial ,
Auricular ,
Orbital ,
Nasal,
Nasal septum,
Ocular
Prosthesis .
Auricular ,
Orbital,
Facial
Obturator ,
Mandibular
Resection ,
Craniofacial
Prosthesis
Auricular,
Facial
Prosthesis
(SUPPORT )
JPD 2OO5

ANCILLARY PROSTHESIS
FEEDING AID
SPLINT
COMMISURE SPLINT
FLUORIDE GEL CARRIER
RADIATION CONE LOCATOR
RADIATION CARRIERwww.indiandentalacademy.com

MISCELLANEOUS
LIP & CHEEK SUPPORT PROSTHESIS
LARYNGECTOMY AIDS
TRACHEOSTOMY OBTURATOR
TONGUE PROSTHESIS
ESOPHAGUS PROSTHESIS
POST MASTECTOMY BREAST PROSTHESIS
VAGINAL RADIATION CARRIERS.
BURNS STENTS
TRISMUS APPLIANCES

Miscellaneous prostheses
Cranial bone prosthesis
Radiation carriers
Nasal prosthesis
Auricular prosthesis

Restoration of nasal defects
The vast majority of nasal defects are
Secondary to neoplasm
(Most) partial nasal defects
Surgery
Rehabilitation
Total nasal defects
Prosthetic restoration
Para amount important ----patient desires

If the defects is going to be temporarily /permanently
restored with a prosthesis
Presurgical consultation with patients & surgeon is
Necessary
In partial rhinectomy defects Surgeon may advice restored
Temporarily with the prosthesis
Surgical reconstruction only after
the suitable observation has elapsed
Covering the defect with a local flap may delay the recovery of
Recurrent tumor

Total rhinectomy cases
Prosthetic restoration is preferable
The prosthesis is to be constructed , the surgeon should be advised
To remove the nasal bone & rest of the bone
Failure to do so makes it virtually impossible to
Fashion a prosthesis that duplicates presurgical
Nasal prosthesis

Remaining nasal bone

Ideally a flat / concave surface is best suited to receive
a prosthesis .
The patient should be informed regarding benefits & limitation
of prosthesis
patients expectation --------- realistic
Psychological evaluations & consultations should begin prior to
The resection
Prior to surgery , facial impression and photographs should
be obtained.

Full facial impression are preferred
Bec’z they provide useful
information for the clinician to
Fabricate the post surgical
Nasal prosthesis .
Undesirable undercuts
Blocked out
Petrolatum gauze

Temporary nasal
prosthesis
Approx 3 to 4 weeks following surgery
Early restoration is appreciated by patients
Heat polymerizing MMA preferred material .
Retention Medical grade adhesive

Definitive
nasal
prosthesis
Effectiveness depends upon the nature &
extent of the prosthesis
Flat defects in which the nasolabial fold remain
are the easiest to restore prosthetically .
Defects of the surgical margins that extend beyond
The nasal area
Difficult to restore
Bec’z of exposure of the lines of juncture .

Margins that extend onto the
Upper lip
Camouflaged by facial hair
Extend laterally beyond the eye Glasses will always apparent
In most patients the residual tissue bed is highly mobile , particularly
When next to the alae / columella
Difficult to account for this mobility with
impression procedure
Prostheses of highly flexible material is advised
more comfort to the patient

Defect extend
onto the lip
Lines of juncture in this
Area was covered
With a mustache

Defect extended
laterally &
inferiorly

Impression techniques in
Definitive nasal prosthesis
As in orbital defects , postural changes may result in
distortions of the tissue bed .
For master impression ----patient should be in
upright position
Elastomeric impression materials ideal for this task
A facial moulage is made , using the preliminary cast
a master impression tray is fabricated confined
to the defect

Sculpting
To be effective nasal prosthesis must reproduce the contour & texture of
The resected nose .
Another imp factor ----------placement & camouflage of the lines of juncture .
In total rhinectomy defect Only small portion of the lines of juncture
Are apparent with a properly sculpted
Nose .
If presurgical cast is not available
Clay / wax should be adapted to the
defect & basic contours are completed .
Reference Facial photographs
Family members .

The alae should be located in their appropriate position in relationship
To the nasolabial folds.
By tucking a portion of the alae into the nasolabial fold these margins
Can readily be made inconspicuous .
Care should be taken not to make the nose too wide in the alar region
Interalar distance > Medial inner canthus distance
Nares should be symmetry & constient with presurgical contours

Small segments of lines of
Juncture is visible .most are
Hidden by eye glasses &
tucked into the
Skin crease & folds
Nares of the
Prostheses
Symmetry

C
O
L
U
M
E
L
L
a
Skin
Eye glass frame -----------improve the appearance of the patients
Always try to place the superior & lateral margins beneath the
Frame.
Reproduction of surface texture is important .

Processing
Two piece molds are adequate
basic shade -----closely match the lightest area of coloration in the
local area
basic shade too dark ---extrinsic coloration

Delivery & retention
Inner surface ---hollowed
retention -----medical grade adhesives
initial adjustments
follow –up schedule constient with life of the prostheses

• For a nasal defect, the anterior surface of the maxilla just
inferior to the nasal cavity offers sufficient thickness of bone
and an optimal position for 4 mm implants.
• Longer implants, 6 mm or greater, are possible in this area.
• A split-thickness skin graft is needed on the sides of the defect
to provide a firm nonmovable foundation for the nasal
prosthesis.
Retention in nasal prostheses

The septal cartilage must be surgically reduced anteriorly and will
reduce the mobility of the tissue bed under the prosthesis and
minimize the stress on the implants.
will provide room for the prosthesis to engage the lateral
walls of the defect and increase the stability of the prosthesis
• A minimum of two implants are required, positioned in each lateral
rounded nasal eminence and the abutments are connected by a bar .

The bar can be extended superiorly 10 to 15 mm from the abutments for
better distribution of retention for the prosthesis.
An acrylic resin section is constructed with the prosthesis to house the
retentive elements. Retentive clips or magnets can be used

Partial nasal prostheses
More of the lines of juncture between prostheses & adjacent margins
will be exposed
Margins –feathered & colored
Acceptable result

Restoration of auricular defects
Defects secondary to congenital malformations , trauma …
Pre operative consultation Extremely valuable
Feathering of the margins & the incorporation of appropriate surface detail .
If surgical reconstructed of the auricle is not contemplated
Entire ear should be removed ---leaving a flat tissue bed
& lined with scalp flap ----making it ideal base .
The tragus should be retained
Bec’z this structure is less obvious anterior line of juncture bet the
Prostheses & the skin .

Residual tissue tag
No retentive value
Prevent sculpture & positioning of
of the prostheses ear .
Temporary auricular prostheses
In most patient tissue bed is organized sufficiently 3 weeks after surgery
fabrication ----heat polymerization of acrylic resin ---periodic adjustment
& relining

Definitive Auricular prostheses
Impressions Unlike orbital defects ,tissue beds in the
auricular area are not displaceable ,
Distortions do not results from postural
Changes
Impression can be obtained pt lying on his side
In a supine position .
Condylar movements closely examined ,
Results in
Tissue bed mobility

Tissue bed mobility
Can affect the
Margin placement ,
Tissue coverage ,
Retention of the prosthesis .
Impression materials –reversible hydrocolloid,
rubber base impression material.

Auricular prosthesis
Impression of the
Defective side
Patient
Position
Defective ear
facing up
External auditory
Meatus ----blocked with wet gauze .
Impression mat
reversible hydrocolloid
Paper clips –reinforcement ,
Plaster Paris –backing .
Impression of the
Nature side

Sculpting
If presurgical cast is available it is reproduced in wax &
compared to the remaining ear
Appropriate changes are made in the basic contours & the wax ear is positioned
& adapted to the defect
To achieve symmetry in all planes with the opposite side

Preoperative cast
Not available
Sculpting
Beginning Donor technique
Time consuming
difficult task
Dividing the cast of the ear
Into equal sections
Contours can be easily verified
Selection ;
Person with ear contours closely
Mimic those of the patient

Orientation lines for positioning of auricular prostheses
Vertical line
Above the helix –
EAM—
LOBE
Horizontal line
Helix ---
EAM—
TRAGUS (beyond )
Defect ear

Orientation lines in stone cast

DIMENSIONAL MEASUREMENT OF THE EAR
SIDE VIEW PROTRUSION VIEW

LAND MARK LOCATION OF THE LAND MARKS
Superaurale (sa) Highest point on the free margin of the auricle
Subaurale (sba) Lowest point on the free margin of the earlobe
Preaurale (pra) Most anterior point of the ear located just in
front Of the helix attachment
Postaurale (pa) Most posterior point on the free margin of the
ear
Otobasion Superius (obs) Point of attachment of the helix in the temporal
region; determines the upper border of the ear
Insertion
Otobasion inferious (obi ) Point of attachment of the ear lobe to the cheek;
determines the lower border of the ear
insertion

A
N
T
E
R
I
O
R
View
P
O
S
T
E
R
I
O
R
View

Alginate impression
Posterior section
Posterior & anterior gray investment
Gray investment
Molds –sprues & ventswww.indiandentalacademy.com

Entire surface must be stippled to match the skin texture of the patients
proper stippling is important
Without it texture of the
adjacent skin can never be suitably
Matched
External tinting may be very difficult
Provides mechanical retention for the
Extrinisic colorants & lengthens the
Period of service of the prostheses

A residual tragus will serve to camouflage approx 25 % of the
anterior margins .
Processing
The wax ear is invested in a manner to construct a three –part mold
Using flexible materials to remove the
Casting from the mold without tearing
Material
Base shade
Processing
Selection
Determination
Surface characterization

Margins is feathered anteriorly
Side burns nicely
Camouflage
Lines of juncture

Three part mold

Conventional retentive devices
Used in auricular prosthesis retention
Eye glass
Tissue adhesives
Extension of the prostheses into ear canal

• The use of transcutaneous implants in the temporal region
for auricular prostheses has shown to be an effective
reconstruction option .
• The temporal bone has sufficient thickness to accept a 3 or 4
mm implant.

A minimum of two implants are needed, positioned
approximately 18 mm from the center of the external
auditory meatus and 15 mm from each other.
The abutments are joined by a bar constructed in a C-shaped
design to improve the stability and retention of the
prosthesis
• The bar can be extended 10 to 15 mm beyond the
abutments for better distribution of stability and retention.

Recent techniques in
Retention of auricular prosthesis
The use of craniofacial implants for retention of extra oral prostheses
Excellent support & retentive abilities
Use of magnets is advantageous over the bar & clips for maintenance .
use of composite bar secured into the implants by gold screw .
magnets incorporate into the fitting surface of the prostheses

Implant abutment
In place
Composite bar secured with
Gold screws
Magnets –
tissue surfacewww.indiandentalacademy.com

Nd –Fe –B magnet
Sealing
Micro laser welding

Retentive bar connects 2
Implants

BTE HEARING AID
(MODULE )

Prosthodontic stents & splints during therapy
Prosthodontic stents & splints may provide significant benefit to
the Radiation therapist by facilitating delivery of therapy to local
areas & thereby limiting post therapy morbidity .
Stents employed to
Protect / displace vital structures ,
Locate diseased tissues in repeatable positions
During treatment , position the beam ,
Carry the radioactive material
dosimetric device to the tumor site ,
usually confined to
The head & neck regions

Positioning stents
Peroral cone positioning devices
Shielding
Recontouring tissues to simplify dosimetry
Positioning radioactive sources
Use of Prosthodontic Splints and Stents During Radiation TherapyUse of Prosthodontic Splints and Stents During Radiation Therapy

Maintaining position
of structures to be
treated
This type of stent is used primarily for
Tongue lesions being treated with external
Radiation .
Many radiation therapists use a cork to
which a tongue blade is taped to confine
The Tongue within the lingual borders
of the mandible
An inferior position of the tongue &
mandible
Therapist to lower the Radiation
field & spare Significant amounts
of parotid glands

An inter occlusal stent is prepared that extends lingually from
Both alveolar ridges with a flat plate of acrylic resin ;
Serves to
Depress the tongue within the lingual borders of the
Body of the mandible .
A hole is made in the anterior segment in which the tip of the tongue
Placed to establish a reproducible positions
Prostheses for the dentulous patients

Extension used to depress theExtension used to depress the
tonguetongue
Tip of the tongue fits in this holeTip of the tongue fits in this hole
COMBINATION OF BITE OPENING & TONGUE POSITIONING
STENT

25 mm25 mm
FOR EASY INSERTION
SHOULD NOT EXCEED 25 MM

Prostheses for edentulous patients
Requires maxillary & mandibular impressions ,
With the use of an interocclusal record , cast are mounted on the
articulator,
Two thickness of base plate wax ----- mandibular record base to
form the portion of the stent
--depress the tongue
An occlusal index should be incorporate into record bases
If the existing denture is adequate ---duplication of the dentures
should be carried out

Duplicated dentures returned to the mouth , they are lined with tissue
Conditioned material , & tongue is positioned as before .
Some clinician prefer intra oral fabrication of the stent using a direct technique

positioners –direct technique

Removing structures from the radiation field
This type of stent is valuable when treating lesions involving the mandibular
alveolus, buccal mucosa, and posterolateral border of the tongue.
The stent separates the mandible from the maxilla, thus sparing the maxilla
from the effects of irradiation. In addition, opening of the mandible often lowers
the field sufficiently to eliminate much of the parotid gland from the radiation
field.
This stent is constructed in a fashion similar to the stent used to depress the
tongue vertically.
The vertical opening should allow maximum separation of the maxilla and
mandible within the limits of comfort.

Removing structures from radiation field
25 mm25 mm
FOR EASY INSERTION
SHOULD NOT EXCEED 25 MM

Large one-piece stents are often difficult to insert, particularly when the
patient begins developing radiation mucositis and trismus.
A two- or three-piece stent may be inserted and removed more easily and
Therefore is more likely to be used by the patient and radiotherapist.

Some superficial oral squamous cell carcinomas in
accessible regions, such as the anterior floor of the
mouth and the hard and soft palate, often may be
treated with the use of a peroral cone.
The obvious advantage of such an approach is
that structures such as the mandible and salivary
glands are spared from the effects of radiation.
Such stents are usable in both dentulous and
edentulous patients and assure repeatable
positioning of the peroral cone during therapy
Positioning peroral
cones

For an edentulous patient, mandibular and
maxillary record bases are fabricated. The actual
peroral cone or a cylinder of the same diameter as
the Cone, is used to form an acrylic resin ring 5 to 6
cm long.
Tinfoil (O.OOl-inch) is wrapped around the cone to
ensure its separation from the auto-polymerizing
methyl methacrylate that is used to form the ring.
Fabrication procedure
Of peroral cone

Stent –positioning peroral cone

IndicationsIndications
Small localized, accessible, superficial lesions of the oralSmall localized, accessible, superficial lesions of the oral
tongue, floor of the mouth or soft palatetongue, floor of the mouth or soft palate

Radiation mucositis

With the radiation therapist present, the acrylic resin
cylinder is attached to the maxillary record base with dental
modeling plastic, and the acrylic resin cone is centered
over the lesion.
This task is most easily performed in the presence of the
patient, but the cast may be used on occasion where the
lesion is easily accessible and visualized
If the dorsum of the tongue protrudes into the end of the
cone, a wax extension may be attached to deflect the
tongue.
Using a beveled cone will usually serve same purpose.

Shielding
This type of stent is only amenable for use with electron beam therapy.
Studies have shown (Wallace, 1971) that a 1 cm thickness of Cerrobend*, a low-fusing
alloy, will prevent transmission of 95% of the electron beam from an
18 MeV machine.
When such radiation sources are employed, important structures can be shielded by the
placement of a stent.
Lesions of the buccal mucosa, skin, and alveolar ridge may therefore be treated, and
effective shields may be fabricated to protect the tongue and the opposite side of the
mandible.

When obtaining the mandibular impression, dental modeling compound is
used to displace the tongue away from the tray on the side for which the
stent is to be fitted.
If the tongue is not displaced at that time, the mandibular cast must be
trimmed
1 cm space is created between the tongue and the alevolar ridge.
Three or four strips of base plate wax are softened and placed between
the teeth, and the instrument is closed to form an occlusal index .

Shielding

Fabrication procedure
(Shielding )
A wax rim 1 to 1 ½ cm thick is prepared to fit into the
reduction of the cast .
Softened wax is placed inside the cast & the instrument
is closed so that a ring outline form can be molded
Lingual ext of wax should be hollowed
to create a cavity 1 cm thick .
Processed by ---MMA

Lead is not suitable material for shielding
Cerrobend alloy as effective as lead
in preventing the passage of an electron beam .
Pouring the stent
around the corner
Block out with clay
Back scatter prevented by -----Auto polymerizing MMA resin

Positioning
dosimetric
device
Radiotherapist occasionally concerned
Regarding CRD /ARD
LITHIUM FLUORIDE CAPSULES ----used as a
Dosimetric are an accurate & efficient means of
Determining dosage locally .
A stent may be employed to position the stent .

Lithium fluoride carrier –positioning dosimetric device

Recontouring tissues to simplify dosimetry
This type of stent is advantageous when treating skin lesions associated with
the upper and lower lips.
When the therapist adjusts the beam for the midline, the dosage delivered will
be less at the corners of the mouth because of the convex curvature of the lips
and face in this region.
A stent can be employed to flatten the lip and corner of the mouth, thereby
placing the entire lip in the same plane. Such stents often are combined with a
shield.

Positioning radio active
Source
Selected superficial oral lesions effectively treated by
Placement of prescribed distance from
the radiation source .
For treament of buccal / palatal
Lesion ----placement of radioactive source in a
maxillary trial denture itself .

Positioning radioactive source by after loading
These stents are similar to those that carry a live source, except that
the radioactive source is placed in the stent after the stent is secured
in its desired position.
Therefore, undue contamination of the clinician is avoided.
This prosthesis is useful primarily in treatment of accessible
superficial lesions.
The stent is fabricated in much the same fashion as radiation carriers
except that Polyethylene Tubing is placed a prescribed distance from
the tumor .

Radioactive source inserted after the carrier positioned
Intraorally

Lesions of the retromolar trigone, buccal mucosa, and tongue
predispose to cheek and tongue biting.
Mucositis and edema during radiation therapy may accentuate this
problem.
A stent can easily be fashioned to displace the tongue and/or
buccal mucosa and help alleviate this problem.
This stent overlays the teeth and may be fashioned of mouth
guard material* on dental stone casts.
Prevention of tongue & cheek biting

In some situations a fluoride carrier can serve the same
purpose.
This stent prevents large metal restorations from
directly contacting oral mucous membranes and,
therefore, prevents localized severe radiation mucositis
secondary to backscatter.

Individually constructed vaginal carriers for
intracavitary therapy using either iridium 192
or radium in specific patients with
carcinoma of the vagina, recurrent
endometrial carcinoma of the vaginal vault,
and carcinoma of the cervix with a narrow
vaginal vault have recently gained favor.
Vaginal carriers

Cranial implants
Etiology of cranial defects
During repair of compound skull fracture
Bone flap reimplanted during elective craniotomy
become infected .
Excision of osteomas
surgically planned external decompression craniotomies .
congential malformation

Indication for cranioplasty
Disfigurement & mechanical
Vulnerability
Small defects
2-3 cm
Location ;
Above the orbital rim ,
Nasion
Cosmetic reasons
Repair for
Large defects
8-10 cm
POJunction
Brain protection

Most cranial defects some variable
Proportion of
Cosmetic Mechanical
Aspects
Decision regarding
Cranioplasty must be influenced by
Age Prognosis Activity level
Specific condition
Of the scalp
Poor candidates for surgery
External prostheses fabricated as an integral part of the wig
Cosmesis Protection

Immediate repair of the cranial defects is not recommended
Bec’z of overt / latent infection
Cranioplasty delayed for ---6 -12 months.
Interim protection
External prostheses
Ideally even in the absence of infectious complication
2-3 mon
Required for proper organization & revascularization of flaps

Methods of cranioplasty
Two basic methods
Osteoplastic
Reconstruction
Restoration with
alloplastic material
Autogenous bone graft
Radiodensity
It’s a viable part of the host tissue
psychological benefits

Autogenous bone graft
Radiodensity
It’s a viable part
of the host tissue
psychological benefits
Possible absortion&
Loss of contour
availability of material
diff in cosmetic

Composite autogenous
Graft
To close small through &
Through defects
Free autogenous graft -----------rib / iliac crest
Ribs are most commonly used
Bec’z availability ,retrievability ,
Less defomorability

More recently Habal et al ---used a polyurethane terephthalate to restore the
Cranial defects
Alloplastic implants
Metals –
Tantalum
Inert & malleable ,
.015 inch perforated sheets ,
The implant inlayed into ledge created
Removing a thickness of the outer table of
Adjacent skull equivalent to the
thickness of the tantalum .
Removal of the contamination by –Nitric acid

Mesh of polyurethane terephthalatewww.indiandentalacademy.com

Titanium
Strong ,
can be strain hardened
radiodensity
.61 mm thick
Tissue acceptability of the implant is enhanced
by anodizing
80%
H3 po4
10%
H2 so4
10%
H2o

Experimental trials
Vitallium
Ticonium
Stainless steel 316 austenite form
Disadvantages
Thermal conductivity ----precipitate head ache
Malleable –leads deformation

Principle advantages of the metals
Malleable ---enables the clinician to shape them to any configuration .
require one incision
readily available .

Autopolymerizing
MMA
Radiolucent
Readily available in sterilized premeasured
Packets of monomer & polymer .
Poor thermal & electrical conductivity .
Mixing a polymer & monomer in polyethylene
Bag & apply the bag on the defect
Prevents monomer contamination ‘
Easy handling

Some clinicians prefer numerous perforation into the prostheses
Maintain fibrous connective tissue
Proliferation
For stability
Fluid may accumulate beneath implant
Can pass to the outer into
Subgaleal space
Can cause tissue reaction
monomer toxicity
difficulty in contouring

Heat polymerizing MMA
IMPRESSION ---- defective part with hydrocolloid
Large cranial defects smaller defects
Scalp –complete shaving
Shaved border of 5cm around the
Bone margins is necessary
When possible clinician should attempt to palpate & mark the margins of the
inner table of bone
Locating the inner table aids in determining the angle necessary for
Contouring the cast to form a margin that will fit .

Parietal temporal defect
Skull radiographs

Larger defect

Impression techniques
Patient position ------upright
Material –reversible hydrocolloid
Thickness of impression ---5 cm
Silicone ---best material for impression Viscosity
Indelible pencil marking
more clearly delineated in the
Impression

Impression obtained with silicon impression material

Prior to preparation
Of the cast
Consultation with
Neuro surgeon
Design of the cranial implant
Inlay the implant into the defect
Remove the outer table adjacent to the defect
Forming a ledge into which implant is fitted
Controversies
Create a thin lip that rests on the unaltered
Outer table around the margins

Prefabricated cranial implant
Inlay type
Onlay type
Extending thin lip

Wax pattern fabrication
Curing –conventional manner
Making of Perforation .
Sterilization ---ethylene oxide at low temp
Prosthesis secured by wire / synthetic sutures .
Impression mat -----bees wax 2/3 + petroleum jelly 1/3 Described by
Elkins

HMMA cranial bone prostheses

Other modification
Combination of autopolymerizing resin
+
stainless steel mesh
Suitable in children's
with thin cranium
Polyethylene
some Properties similar to MMA
Gas sterilization .
Silicone
Tissue compatability +flexiblity
Medical grade silicone
In 3 forms
Blocks –carved to desired
shape
Heat vulcanization form
Room vulcanization form

Conclusion
There are many individual presentation&
varying challenges in supplying patients with prostheses
for maxillofacial defects & the restorative dentist
has to be imaginative & innovative .
As for any other successful treatment , the important
Feature is to be aware of the principles & to stick with them

References
( Books)
Text book of maxillofacial
prosthesis
VAROUJAN CHALIAN
Text book of maxillofacial
Prosthetics
WILLIAM R. LANEY
Maxillofacial
Rehabilitation
Beumer

References
(journals )
Cranial prostheses
JPD 1998 ;79 :229 -231
Modification of
Cranial implant prostheses
JPD 1984 ;52 :414 -417
Retention of facial prostheses
JPD 1980;43:552-560
Auricular retention
JPD 2001 ;86:386-389

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Miscellaneous prosthesis /orthodontic practice

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