Complete overdenture(3)
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Transcript of Complete overdenture(3)
Prof. Dr. Ahlam El-Sharkawy Pharos University in Alexandria
Introduction
Extraction of teeth followed by continuous ridge resorption & poor denture foundation
Loss of periodontal receptors responsible for proper masticatory function & accurate jaw movements
Retention of few remaining teeth to support denture will preserve alveolar bone & preserve periodontal receptors
Definition of overdentures Complete or partial denture constructed over existing
teeth, roots or implants for providing additional support, stability & retention
Called also:
Overlay denture
Overlay prosthesis
Superimposed prosthesis
Types 0f over-Dentures. -Tooth supported over-dentures.
- Implant supported over- denture.
Prof. Dr. Ahlam
El-Sharkawy
Indications 1. Cases having few hopeless teeth unsuitable as
abutments for fixed or removable bridges
2. Patient having few remaining teeth with periodontal disease.
3. Patient with abnormal jaw size or position
4. Patient with congenital or acquired defects as cleft palate ,dentinogenesis imperfecta
5. Patient with single denture
6. Patient exhibit flat ridges
Contra-indications 1. Mentally or physically handicapped
2. Patient can’t be motivated to develop good oral hygiene
3. Inadequate intermaxillary space
4. Teeth with grade III mobility or insufficient zone of attached gingiva
1- submerged roots Abutments roots are endodontically treated .
Reduced in height to a level below gingival margin
2- dome shaped abutment with amalgam plug mmmmmm
Abutments reduced to be 1-2 mm above gingival margin to reduce lateral force & torque
Endodontic treatment is necessary
The root canal is filled with gutta percha
The opening is sealed with amalgam plug.
The abutment is contoured to attain dome- shape.
Used in patient with low caries index &good oral hygien.
3- dome shaped abutments with cast copings
Abutment are endodontically treated & reduced to 1-2 mm above gingival margin
Metal dome shaped cast coping constructed to cover abutment
The metal coping has a short post cemented into root canal to retain the coping
4- abutments with telescopic crowns
Abutment teeth are either vital or endodontically treated & contoured to tapered configuration
Tapered metal copings constructed &cemented over abutments
Denture constructed with metal crowns having veneered facings
5- abutments with slight tooth reduction & cast copings Abutments are minimally reduced
With or without endo treatment
Covered with cast metal coping “long coping abutment”. This type is rarely followed because it
requires adequate ridge space
Endodontically treated, reduced & covered with metal coping
Coping has a long post to help retention
Attachment added either by soldering or during wax pattern
6- abutments with an added form of attachment
Types of tooth supported Over-dentures 1. Immediate over-denture
2. Interim over-denture
3. Definitive over-denture
4. Attachment retained over-denture
Immediate overdenture Constructed prior to preparation of abutment teeth &
ready for insertion after preparation& reduction
It enhances patient’s ability & adaptability to wear dentures
Interim overdenture Used for patients in transition or preparation phase
until permanent overdenture constructed
Patient old partial denture can be modified & used by extending the denture & add new artificial teeth using self cure acrylic resin
Definitive over-denture Conventional complete over-denture constructed over
1 or more abutment teeth
Could be made entirely of acrylic resin or in conjunction with metal bases
Attachment retained over-denture Constructed with an incorporated attachment to
improve retention
More expensive & more time for construction
Indicated for patient with good oral hygiene & low caries index
The abutment teeth should have good periodontal condition & adequate bone support
Types of Attachments a) Rigid attachment
Doesn’t allow movement of denture base
Provide adequate retention
May induce more torque on abutment
b) Resilient attachment
Allows some control of movements.
Induces less torque on abutments.
Over-Denture Attachment could be in the form of:
1- Stud Attachments.
2- Bar attachments.
3 Magnetic Attachments.
1- Stud attachment Consists of 2 parts
The stud usually attached to metal coping cemented over prepared abutment
Housing embedded in the fitting surface of overdenture
1- Stud attachment Extra-Radicular : The stud is attached to the metal
coping cemented over the prepared abutment, while the housing is embedded in the fitting surface of the denture. e.g : Ceka , Rotherman, Gerber
1- Stud attachment B- Intra-Radicular: The stud is attached to the fitting
surface of the denture and the housing is incorporated in the abutment. e.g : Zest Anchor
eg
2-Bar attachment A bar contoured to connect abutment teeth together ,
run parallel & overlie residual ridge
Provide support & retention for overdenture & splint abutment teeth
Bars may be in form of preformed metal or plastic
A- Bar units Rigidly fixed to copings, don’t allow any movement
between bar & sleeve
Transmits occlusal stresses totally to abutments “tooth born”
B- Bar joints Resilient attachments allowing movement between
bar & sleeve
Support provided by both residual ridge & abutment teeth “tooth tissue born”
3- magnetic attachments Small, strong mini magnets
One of poles cemented in a prepared cavity in endodontically treated abutment & the other attached to denture base