Prosthetics I.
Completed material with
feedback
Rehabilitation of the masticatory
apparatus
Damaged teeth
­ reconstruction of the crown
Missing teeth
- appropriate prothesis (denture)
Prothesis
* Individually made, situation in patients is
different.
* Differences
in the type of defect, extent and location
in the size, shape and position of teeth
in the quality of hard and soft tissues of
the oral cavity
in intermaxillary relations
Prothesis (denture) ­ the goal
Rehabilitation of:
Function
Comfort
Aesthetics
Fonation
Fixed dentures
* Cemented on the teeth ­ crowns, bridges,
inlays
Inlay ­ reconstruction of a part of damaged
tooth
Crown ­ reconstruction of anatomic form of
the whole tooth
Bridge- replacement of missing tooth/teeth
Removable dentures
* Partial
* Complete (full)
Procedures
In dental surgery
In dental laboratory
Special instruments
Basic (main) materials
(metal alloys, ceramics,polymers)
Auxilliary (accessory) materials
(impression, carving, die, insulating
investing, grinding, polishing)
Manufacturing of dentures
Model of gypsum (plaster) ­ model of a
denture (wax pattern).
Model of a denture (wax pattern) directly in
the mouth ­ rarely.
Denture is formed without a wax pattern in
the dental lab.
Manufacturing of dentures
Model of gypsum (plaster) ­ model of a
denture (wax pattern) ­ fabrication of
denture. Operations in dental office and in
dental lab.
Impressions of the jaw - negativ
The impression is filled with a casting
material (gypsum) ­ poured into
Model
(various purpose)
Models
Working model ­ the denture is produced on
this model (special procedures)
Opposing model (antagonal) - necessary for
the recognition of intermaxillary relationship
Bite regitration - wax
Manufactoring of dentures
The denture (not the denture itself but the
model of the denture) is produced on the
working model.
The model of the denture is made of the
carving wax.
The wax is replaced by the main (base)
material.
Fabrication of dentures
The model (wax) of the denture is invested
The wax is removed from the form and the base
material is placed into the form.
Wax removal:
The wax is burned out (for metal alloys)
or removed by hot water (for polymers ­ acrylic part of
dentures)
Impression material
Tooth
Impression
Gypsum
(poured into the impression)
Impression
Plaster
(Gypsum)
This is a model
The wax pattern
The model
The wax pattern
This
The investing material
The form
The melted alloy
The investing material
The crown
The melted alloy
The investing material
The metal crown
Plaster
Manufacturing of dentures
The method described above = indirect
Method (impression, model, pattern,
denture)
Manufacturing of dentures
Direct method
(Without impression, the pattern is formed
directly in mouth, the fabrication takes
place in a dental lab)
Manufacturing of dentures
Direct method
No impression
The model of the denture is made directly in
the mouth
For inlays only
Planning of the denture
Complex examination
1. Extent and location of the defect
2. Damage of the involved teeth (caries, fillings atc.)
3. Periodontium
4. Shape, size, position of teeth, relationhip to the neighbours
5. Occlusion, articulation ­ relationship to the antagonists
6. Quality of the alveolar process
7. The level of oral hygiene
8. X-ray examination
9. Study impressioons ­ study models
10. Detail evaluation of the abutment teeth (pilots) ­ most impoprtant
teeth ­canines, premolars
Classification of defects of dentition
acc.to Voldřich
I. Class
One or more teeth are missing
Small gaps ­ 1 ­ 2 teeth
Big gaps 3 ­ 4 teeth at most. This big gaps
must be demarcated by pilot of the best
quality. (canine, 1st or second molars pilots
of 1st class or their equivalents)
Classification of defects of
dentition
acc.to Voldřich
II. Class
Reduced dental arch, thenlast tooth is the
second molar.
With gaps
Without gaps
Bilateral
Unilateral
Classification of defects of
dentition
acc.to Voldřich
III. Class
Individual teeth or small groups of teeth
Classification of defects of
dentition
acc.to Voldřich
IV. Class
Edentulous dental arch
Classification of dentures
Class I.
Dentures with dental transfer of masticatory
Forces
Class II.
Dentures with combined transfer of
masticatory forces
Classification of dentures
Class III.
Dentures with gingival (mucosal) transfer of
masticatory forces, sometimes the
transfer can be combined.
Class IV. ­ gingival (mucosal) transfer of
masticatory forces.
Classification of the pilots
(abutment teeth)
I. Class pilots
Canines
Molars (1st, 2nd)
Sometimes 3rd molars with excellent
biological factor
Classification of pilots (abutment
teeth)
II. nd class pilots
Incisors - maxillary incisors, premolars
All pilots of class I.with worse biological
factor
Classification of pilots (abutment
teeth)
Pilots III. class
Mandibulary incisors, third molars, all teeth
with bad biological factor
Biological factor
Comprehension of properties which
influences the quality of teeth.
Biological factor
Caries
Pulp vitality
Level of the endodontic treatment
Level of the resorption of the alveolar bone
Periodontium
Relationship to antagonists
Relationship to neihgbour teeth
Way of the transfer of masticatory
forces
Tooth (fixed dentures, removable dentures
class I.)
Tooth and oral mucosa (removable
dentures class II, or some cases
removable dentures class III.)
Oral mucosa ( most class III. removable
dentures, complete denture)
Control questions
What are the goals of the prosthetic
treatment?
What is a biological factors?
What class acc. to Voldřich is a dentition
with
gaps?
Control questions
What class acc. to Voldřich is a reduced
dental arch?
What defects are the class III?
Which way of the transfer of masticatory
forces is in comlpete dentures?
Control questions
Describe pilots I., II. III. Class
What is the biological factor?
Describe the principle of indirect fabrication
of denture (and direct fabrication).
Control questions
What is the method of lost wax?
What should be taken in account during the
planning of the prosthetic treatment?