• Silastic 382 can be moulded without difficulty with the simple bench
press pressure. RTV silicones are virtually unaffected by oxygen,
• Intrinsic colouring agents: Methyl methacrylate monomer, polymer
and ferrous oxide pigments in Silastic base.
• Extrinsic colouring agents: Methyl methacrylate monomer–polymer
admixture in a precatalysed Silastic base.
• Air bubbles incorporation: To compensate, mixing has to be done on
flat surfaces. If a void occurs on the surface of the finished product,
repair can be instituted by meticulously cleaning the surface with
xylene and by adding a fresh mixture of precatalysed material in
• Dif iculty in internal colouring: As the material is white, translucency
is decreased. In order to overcome this, clear Silastic C55 392 can be
• Low edge strength: To overcome this, white nylon material is
embedded in the prosthesis. This gives added strength.
• High weight: To overcome this, a foam-type Silastic (55370) for the
internal portion of the thick prosthesis can be used.
• Special adhesives are used in retention of prosthesis. To offset the
deleterious effect of adhesives, mechanical retention employing
undercuts, magnets or other means are preferred.
It is in the form of a clear gel which makes tinting appreciably easier.
It resembles white Vaseline in raw state, easily spatulated but
nonflowing. Upon mixing with first catalyst (the cross-linking agent),
it becomes somewhat milky; when the second catalyst is added, it sets
into a translucent rubber in 10–15 min.
• It is tougher, translucent, nonflowing and easier to handle.
• Silastic 386 is a form of RTV silicone.
• The purpose of foaming is to reduce the weight of prosthesis.
• The gas forms bubbles within the vulcanizing silicone. After
processing of silicone, gas is released resulting in a spongy material.
• Formation of bubbles within the mass can cause the volume to
• It reduces the weight of the prosthesis.
• It results in reduced strength and is susceptible to tearing.
• To improve the properties, the foaming silicone is coated with
another silicone. Although it improves the strength, the product is
Stents and splints used in maxillofacial
Stent is defined as ‘any device or mould used to hold a skin graft in place or
provide support for anastomosed structures’. (GPT 8th Ed)
Splint is defined as ‘a rigid or flexible device that maintains in position a
displaced or movable part’. (GPT 8th Ed)
(ii) Functional occlusal splint
• This prosthetic device is fabricated to hold together fractured
segments of edentulous mandibular or maxillary jaws for
• One-piece gunning splint consists of upper and lower base plates
that are joined in proper vertical and centric relation with a bite rim.
This splint is immobilized by an extraoral Barton bandage or elastic
• Two-piece gunning splint consists of separate splints for both
maxilla and mandible. Both the bite rims are constructed in centric
relation and in the anterior region; space is provided to facilitate
breathing, feeding and postanaesthesia vomiting.
• Two to four wire hooks are provided on the buccal flange for future
anchoring with intermaxillary rubber bands.
• It is constructed for dentulous or partially edentulous arches to aid
in reduction of fractures in children.
• Splint consists of an acrylic band that fits around the labial and
lingual aspects of the teeth, except the occlusal surfaces.
• The maxillary and mandibular labiolingual splints are joined in
occlusion by intermaxillary rubber bands (Fig. 31-2).
FIGURE 31-2 Labiolingual splint.
• This is a one-piece prosthetic device contoured to fit a dentulous
maxilla and mandible through fenestrations created for the occlusal
• It is used in case of short clinical crowns, for deciduous teeth, when
no undercut is available for retention and for badly decayed teeth.
• It is constructed for both dentulous and edentulous patients and
covers the palate and the alveolar ridge.
• It has anterior extension of the metal rods protruding bilaterally
from the commissures of the mouth.
• It is helpful in lifting the fractured maxilla.
• This splint is immobilized by an extraoral plaster headgear.
• This type of splint is used when long-term immobilization is
• Cobalt–chromium–aluminium and gold are the common materials
• This splint may be left open at the occlusal surface or it may be
• Its disadvantage is that it is expensive and its fabrication is timeconsuming.
• It is used to control bleeding, as it is lined by haemostatic agent
FIGURE 31-3 Antihaemorrhagic stent.
• It is a diagnostic and therapeutic device used for the evaluation of
occlusion and vertical dimension in the treatment of
temporomandibular joint pain dysfunction syndrome.
These are of two types, namely, externally activated stent and
internally activated stent (Fig. 31-4).
FIGURE 31-4 Trismus screw for bite opening.
• Continuous dynamic jaw extension apparatus
• It is used to deliver the radiation dose to the local area in order to
limit the post-therapy morbidity (Fig. 31-5).
FIGURE 31-5 Peroral cone positioner to deliver radiation
• To maintain the position of structures to be treated
• To remove structures from the radiation field
• To position the dosimetric device
• To recontour tissues to simplify dosimetry
• To position the radioactive source
• This type of stent provides support to the cartilage transplant
during postsurgical healing for the correction of the nasal deformity
• These help in maintaining contour and minimize scar contracture
following skin grafting procedure.
• Ambroise Pare (1517–1590) was first to close palatal perforations.
• Tycho Brahe (1546–1601) was famous Danish astronomer who
made an artificial nose of gold and silver.
• First artificial eye was made of glass in 1579 in Venice.
• Pierre Fauchard (1728), considered as the father of modern
dentistry, used palatal perforations to retain artificial dentures.
• Snell (1823) fabricated gold plate obturator.
• Goodyear (1855) developed vulcanite rubber used for improved
• Bulbian (1942) introduced the use of prevulcanized latex for pliable
facial prosthetic restoration.
• American Academy of Maxillofacial Prosthetics was formed in 1953.
• Branemark and associates first placed extraoral implant in the
mastoid region to support a bone conduction hearing aid in 1977.
• BAHA, i.e. bone-anchored hearing aid, was approved by the
Swedish health system in 1988.
• Barnhart was first to use silicone rubber for construction and
colouring of facial prosthesis.
• George Washington springs are preformed springs which are
inserted into the upper and lower set of dentures to stabilize them
on the ridges during function.
• Newer orbital implant materials are polyethylene implants,
bioceramic implants and synthetic HA implants.
Dysfunctions Associated with Cleft Palate
Rehabilitation of Cleft Lip and Palate
Prosthodontic Rehabilitation of the Cleft Palate
Types of Removable Prosthesis, 438
Aramany’s Classification of Maxillary
Prosthetic Management of the Mandibular
Auricular Prosthesis or Ear Prosthesis, 448
Retention Aids in Maxillofacial Prosthesis, 451
Role of Magnets in Maxillofacial
The maxillofacial defects often require prosthetic intervention in
restoring the contours of defect and restoring the function of the
tissues. This chapter includes various defects and different types of
maxillofacial prosthesis used to restore such defects.
Maxillofacial defects can be classified as follows:
On the basis of location or area involved
• Any combination of the intraoral and extraoral
Cleft palate is defined as ‘an opening in the hard/or soft palate due to
improper union of the maxillary process and the median nasal process during
the second month of intrauterine development’. (GPT 8th Ed)
Classification of cleft palate
V. Veau (1922) classified cleft palate as follows:
Class I: Cleft involving the soft palate only; can also be submucous
Class II: Midline cleft involving the posterior part of the hard palate.
Class III: A unilateral cleft extending along the mid-palatine suture
and a suture between the premaxilla and the palatine shelves (Fig.
Class IV: A unilateral cleft extending along the mid-palatine suture
and both the sutures between the premaxilla and the palatine
Dysfunctions associated with cleft palate patient
• Tight, inactive or hypotonic upper lip
• Abnormal position of the tongue and the jaw
• Altered maxillary vertical development
• Changes in lower face height
Rehabilitation of cleft lip and palate patients
Rehabilitation of the cleft palate involves multidisciplinary approach
involving number of specialists.
Primary consideration for such patients depends on the following:
• Extent and location of the cleft
• Growth potential of the patient
Prosthodontic rehabilitation of the cleft palate
Primarily, two types of appliances are given:
(i) Passive or holding appliance
(ii) Active or expansion appliance
All the appliances are fabricated or inserted before the lip closure.
The primary aim of the appliance given before surgery is to guide the
maxillary segments into proper spatial position with each other and
Once the segments are in good alignment, surgery is performed to
close the defect. The pressure of the surgically closed cleft lip along
with the appliance is helpful in creating an ideal arch form.
Prosthetic appliance for children
Three types of appliances are given to aid in speech, which are:
(i) Obturator with palatal–velar–pharyngeal closure: It is a type of
temporary appliance which is used for diagnosis and training.
(ii) Baseplate type with functions to obturate the palate and helps in
speech. This is indicated when there is perforation in the hard palate
and the surgeon desires more growth of the child before surgical
(iii) Anterior prosthesis which improves the occlusion and helps in
contouring the upper lip: Because of the stunted growth of the maxilla
and the normal growth of the mandible, mandibular prognathism is
often seen in such patients. This appliance is used to improve the
appearance of the patient at this stage.
(i) Fixed prosthesis: It is the treatment of choice when the ridge defect
is small, as it contributes to stability, longevity, comfort and hygiene.
A fixed partial denture can be constructed from
cuspid-to-cuspid in the maxilla to restore the
integrity of the maxillary arch by stabilizing the
premaxilla and to provide adequate aesthetics.
(ii) Removable prosthesis: It is preferred, if there is a large anterior
ridge defect and the midface is depressed.
(i) Snap on prosthesis with no speech bulb.
(ii) Removable partial denture with no speech bulb: This is indicated
in large ridge defect and extremely poor occlusion.
(iii) Complete superimposed denture with no speech bulb: Overlay
denture restores the vertical dimension of the face and gives an arch
form to the upper arch. Also, all the teeth are restored.
(vi) Snap on prosthesis with speech bulb: It helps in velopharyngeal
valving. The pharyngeal section is placed high to prevent any
interference with the tongue movement.
(v) Conventional speech prosthesis with bulb: A patient with all the
teeth need only framework that can clasp the healthy abutment teeth.
This framework carries the palatal, velar, pharyngeal portion
necessary for speech impairment.
(vi) Complete superimposed denture with speech bulb: Overlay
denture may or may not have the speech bulb. It is indicated in
patients with loss of vertical dimension with hypernasality and
having dished out appearance of the midface.
Obturators are defined as ‘a maxillofacial prosthesis used to close a
congenital or acquired tissue opening, primarily of the hard palate and/or
contiguous alveolar/soft tissue structures’. (GPT 7th Ed)
Obturator is derived from the Latin verb ‘obturare’ which means ‘to
• To restore aesthetics or cosmetic appearance of the patient
• To provide psychological therapy
• Has a therapeutic or healing effect
(I) Classification by A.O. Rahn and L.J. Boucher
On the basis of origin or discrepancy
(i) Congenital defect obturator
(ii) Acquired defect obturator
On the basis of anatomical location of the defect
On the basis of type of obturator attachment to the basic maxillary
On the basis of physiological movement of the oral, nasal and
pharyngeal tissues adjacent to or functioning against the obturator
(II) Classification on the basis of timing of the
(ii) Interim or temporary obturator
Historical background of obturators
Ambroise Pare was the pioneer to use obturator to close palatal
perforations in the early 1500s.
Pierre Fauchard described two types of palatal obturator; one type
had wings in the shape of propellers and the other type had
butterfly-shaped wing for retention. Both types were operated by a
William Morton (1819–1868) is known to treat cleft palate patient
Delabarre described hinged obturator in 1820.
Claude Martin described the use of surgical obturator prosthesis in
Norman Kingsley described a method to reconstruct the palatal
E. Fry described the use of impressions before surgery in 1927.
American Academy of Maxillofacial Prosthetics was established in
B. Steadman described the use of an acrylic resin prosthesis lined
with gutta-perch to hold a skin graft within the maxillectomy defect
K.W. Coffey: In 1984, he first described the inflatable balloon
obturators which were useful in minimizing displacement of soft
• Helps in enhancing the healing of the postsurgical or traumatic
• Can be used for feeding purpose
• Helpful in reshaping and reconstruction of the palatal contour
• Can improve aesthetics by correcting the lip and cheek contour
• Prevents ingress of food into the defect or exudates into the oral
• Can be used as a stent to hold dressing or surgical packs after
• Provides psychological comfort to the patient
• Reduces postoperative bleeding
• When size and extent of the defect contraindicate surgery
• To serve as temporary prosthesis during surgical correction
• Old age patient where surgery is contraindicated
• When local avascular conditions of the tissues contraindicate
• To rapidly restore patient’s cosmetic appearance
• To act as a framework over which tissues are shaped by the surgeon
• Patient’s medical condition which contraindicates surgery
• When the patient is not willing for another surgery
Obturators are of three types on the basis of interventional time
period used in the maxillofacial rehabilitation of the patient:
Surgical obturator is defined as ‘a temporary maxillofacial prosthesis
inserted during or immediately following surgical or traumatic loss of a
portion or all of one or both maxillary bones and contiguous alveolar
structures (i.e. gingival tissues, teeth)’. (GPT 8th Ed)
(i) Immediate surgical obturators: Placed immediately after surgery.
(ii) Delayed surgical obturators: Placed 7–10 days postsurgery.
Principles related to the design of surgical obturator (J. Beumer,
• It should terminate short of the skin graft mucosal junction.
• It should be simple, light weight and inexpensive.
• It should reproduce palatal contours to aid in postoperative speech
• Posterior occlusion should not be given on the defect side until the
surgical wound is well healed.
• Existing prosthesis can be utilized as surgical obturator provided it
will obturate the surgical defect adequately.
• Obturator for the dentulous patient is perforated at the
interproximal extensions with a small dental bur to allow the
obturator to be wired to the teeth at the time of surgery.
• It provides the matrix on which the surgical packing can be placed.
• It reduces the oral contamination of the wound immediately during
• It aids in speech and deglutition.
• It reduces the psychological trauma of surgery.
• It may reduce the period of hospitalization.
• Anterior teeth, if required, may be added to enhance the aesthetics.
• Impression is made of the upper arch before surgery and cast is
• Teeth in the path of resection are trimmed on the cast.
• The vestibular depth on the defect side determines the superior
• Surgical obturator is fabricated with either autopolymerizing resin
• Heat-cured resin is generally preferred.
• Holes are provided in the flange region to aid in wiring to the
alveolar ridges or zygomatic arch or nasal spine. At times,
circumzygomatic and frontal wiring is employed to support the
• Clear acrylic resin is recommended as the extensions and the
pressure areas are easily visualized at the time of surgery (Fig. 32-3).
FIGURE 32-3 Surgical obturator.
Interim obturator is defined as ‘a maxillofacial prosthesis which is made
following completion of the initial healing following surgical resection of a
portion or all of one or both maxillae; frequently many or all teeth in the
defect area are replaced by this prosthesis’. (GPT 8th Ed)
• Interim obturators are fabricated after the defect margins are clearly
defined and further surgical revisions are not planned.
• These obturators are used till healing of the surgical site is complete
and the site is dimensionally stable.
• This type of obturator is fabricated from the postsurgical impression
cast which has false palate, false ridge and has no teeth.
• Closed hollow bulb extends into the defect.
• Patient is recalled after every 2 weeks for evaluation, as there are
rapid changes occurring within the defect due to healing of the
• The interim prosthesis is relined frequently.
• It is advisable to change the reline material rather than placing over
the old one to avoid bacterial contamination, mucosal irritations or
precipitation of undesirable odour.
FIGURE 32-4 Interim closed hollow bulb obturator.
Definitive obturator is defined as ‘a maxillofacial prosthesis that replaces
part or all of the maxilla and associated teeth lost due to surgery or trauma’.
• This type of prosthesis is indicated when the surgical site is
completely healed and is dimensionally stable.
• It is usually given after 6 months of surgery.
• The timing of the obturator fabrication will depend on the size of
the defect, progress of healing, prognosis of tumour control and
• It is important to fabricate a definitive prosthesis, as the periodic
relining of the interim prosthesis makes it heavy and bulky.
• Secondly, it may become rough and unhygienic.
• Thirdly, retention and stability of the prosthesis can improve by
adding teeth on the defect side.
• Changes associated with healing and remodelling will continue to
occur in the border areas of the defect for at least 1 year.
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