DENTURE REPAIR

Fractured dentures

cause is due to patient dropping the dentures, some dentures break in the mouth

repeated breakage

Repair of the denture without determining the cause of the breakage

repeated breakage

Common when the dentures break within the mouth

Denture Factors AND Patient Factors

CAUSES OF FRACTURES OR CRACKS CAN BE CATEGORIZED AS:

Denture Factors

o Fracture of the denture base o Fracture of a tooth or teeth on the denture

Patient Factors

Accident o Anatomical factors o High occlusal load

Poor fit o Incorrect tooth position

The denture base can fracture due to two main reasons:

alveolar resprption, warpage, relief, inaccurate impression

factors causing poor fit

ALVEOLAR RESORPTION

will cause the denture to be unevenly supported and cause fracture.

WARPAGE

Dimensional changes in acrylic resin

Excessive relief

can make the denture thin and fracture

INACCURATE IMPRESSION OR CAST

can induce considerable stresses in the denture base during mastication

setting upper teeth outside the ridge

most common cause incorrect tooth postion

Wide extension of the denture base, Arranging teeth in balanced occlusion, Use of metal denture base

ways to counter incorrect tootg position

denture bases

primarily for stabilization

metal-reinforced (or fiber-reinforced) acrylic base

if a denture fracture is caused by excessively high masticatory loads, a new denture might be made with

o Cuspal interference o Excessive grinding of a tooth

FRACTURE OR DEBONDING OF A TOOTH OR TEETH

CUSPAL INTERFERENCE

Where the pressure is heavier on one tooth than elsewhere, it will frequently cause the tooth to split,

preferable to either reline or rebase the denture

If the fracture is associated with design faults or has resulted from alveolar resorption,

consideration should be given to making a new denture

Where the cause of the fracture is thought to be excessively high masticatory loads

ACCIDENT

the most common cause of fractured denture due to impact

frenal notches

that act as stress raising features, resulting in crack initiation and subsequent propagation

frenal notches

resulting in crack initiation and subsequent propagation

HIGH OCCLUSAL LOADS

present in patients with powerful muscles of mastication, bruxers, and single complete dentures

OBTURATORS

A prosthesis used to close a congenital or acquired tissue opening, primarily of the hard palate and/or contiguous alveolar structures

- To provide the capability for the control of nasal emission during speech - To prevent the leakage of material into the nasal passage

OBJECTIVES OF OBTURATORS

▪ Surgical ▪ Interim ▪ Definitive

Based on the phase of treatment

▪ Metal ▪ Resin ▪ Silicone

Based on the material used

▪ Meatal ▪ Palatal

Based on the area of restoration

SURGICAL OBTURATORS

used to restore the continuity of the hard palate immediately after surgery

IMMEDIATE SURGICAL OBTURATOR

inserted at the time of surgery

DELAYED SURGICAL OBTURATORS

inserted 7- 10 days after surgery

INTERIM OBTURATORS

A prosthesis that is made several weeks or months following the surgical resection of a portion of one or both maxillae.

INTERIM OBTURATORS

frequently includes replacement of teeth in the defect area

INTERIM OBTURATORS

is constructed from the postsurgical master cast

INTERIM OBTURATORS

has a false palate, false ridge, o teeth, and a closed bulb

DEFINITIVE OBTURATORS

A prosthesis that artificially replaces part or all of the maxilla and the associated teeth lost due to surgery or trauma”

METAL OBTURATORS

are used to obtain bone anchorage for a prosthesis.

METAL OBTURATORS

may also be used to make denture bases

Implant metals

used are mostly titanium alloys

Base metal alloys

used for denture base fabrication

RESIN

preferred for restoring defects that require minimal movement like ocular prosthesis

RESIN

disadvantages include the rigid property of the material and difficulty in duplicating the prosthesis

SILICONE

the most commonly used material for facial restoration

SILICONE

poor tear strength and life-less appearance have limited them from universal acceptance

SILICONE

are a combination of organic and inorganic compounds

SILICONE

manufactured from silica

Implant grade

silicones placed within the tissues (breast implants). They must meet or exceed FDA requirements

Medical grade:

obturators approved for external use only.

Medical grade:

the most commonly used variety for fabricating maxillofacial prosthesis

MEATAL OBTURATOR

a special type of obturator that extends up to the nasal meatus

MEATAL OBTURATOR

establishes closure with the nasal structures at a level posterior and superior to the posterior border of hard palate.

MEATAL OBTURATOR

separates the oral and the nasal cavities

MEATAL OBTURATOR

for patients with extensive soft palate defects

PALATAL OBTURATOR

Closes or occludes opening caused by cleft or fistula

PALATAL OBTURATOR

Used to facilitate separation of oral and nasal cavities for speech, feeding, swallowing, and hypernasality

o Diagnosis and Treatment Planning o Prelimenary Impression using Alginate o Fabrication of Custom Tray o Border Moulding o Final Impression with Elastic Impression material o Jaw Relation o Teeth Arrangement o Insertion and post-insert

FABRICATION OF PALATAL OBTURATOR - STEPS

velo-pharyngeal extension

can be recorded by asking the patient to swallow

elastic recoil

purse string action

elastic recoil

responsible for the retention of the obturator

simple clasps

If the patient is dentulous, retention is obtained with __

the obturator is wired into the alveolar ridge and the zygomatic arch.

If the patient is edentulous, __

7 to 10 days after surgery.

immediate surgical obturator is retained for __

lining material

delayed surgical oburator can be converted nto an interim obrturator by adding __

obturator bulb

ecessary to seal a posterior palatal cleft